title: New constraints on multi-field inflation with nonminimal coupling

abstract:
  We study the dynamics and perturbations during inflation and reheating in a
multi-field model where a second scalar field $\chi$ is nonminimally coupled to
the scalar curvature $(\frac12 \xi R\chi^2$). When $\xi$ is positive, the usual
inflationary prediction for large-scale anisotropies is hardly altered while
the $\chi$ fluctuation in sub-Hubble modes can be amplified during preheating
for large $\xi$. For negative values of $\xi$, however, long-wave modes of the
$\chi$ fluctuation exhibit exponential increase during inflation, leading to
the strong enhancement of super-Hubble metric perturbations even when $|\xi|$
is less than unity. This is because the effective $\chi$ mass becomes negative
during inflation. We constrain the strength of $\xi$ and the initial $\chi$ by
the amplitude of produced density perturbations. One way to avoid nonadiabatic
growth of super-Hubble curvature perturbations is to stabilize the $\chi$ mass
through a coupling to the inflaton. Preheating may thus be necessary in these
models to protect the stability of the inflationary phase.


title: Spin effects in B_c -> X_cc + \pi (\rho) decays

abstract:
  The two-particle hadronic decays of B_c meson into S-wave and P-wave
charmonium states X_cc are considered in the framework of hard gluon exchange
model. It is shown that decay width of B_c meson into S-wave charmonium states
doubly exceeds one for S-wave states. In compare with the previous estimations
we predict the enhancement by 8 % the branching ratio for the B_c decays into
J/psi in the two-particle hadronic decays via the contribution of the radiative
decays of P-wave states in the cascade processes.


title:
Time-reversal-violating birefringence of photon in a medium exposed to
  electric and magnetic field

abstract:
  The T-reversal-violating optical gyrotropy is discussed. An expression for
dielectric permittivity describing T-reversal-violating phenomena in a medium
exposed to external electric and magnetic fields is presented. Optical
phenomena of birefringence and polarization plane rotation of photon in a
medium exposed to external electric and magnetic fields are considered.


title: Testing the Randall-Sundrum Model at a High Energy $e^- e^-$ Collider

abstract:
  We study the process $e^- e^- \to e^- e^-$ at a high energy $e^- e^-$
collider including the effect of graviton exchanges in the warped gravity model
of Randall and Sundrum. Discovery limits for gravitons are established and the
effects of polarization are discussed.


title:
The Infrared Behavior of QCD Green's Functions - Confinement, Dynamical
  Symmetry Breaking, and Hadrons as Relativistic Bound States

abstract:
  Recent studies of QCD Green's functions and their applications in hadronic
physics are reviewed. We briefly discuss the issues of gauge fixing, BRS
invariance and positivity. Evidence for the violation of positivity by quarks
and transverse gluons in the covariant gauge is collected, and it is argued
that this is one manifestation of confinement.
  We summarise the derivation of the Dyson-Schwinger equations (DSEs) of QED
and QCD. The influence of instantons on DSEs in a 2-dimensional model is
mentioned. Solutions for the Green's functions in QED in 2+1 and 3+1 dimensions
provide tests of various schemes to truncate DSEs. We discuss possible
extensions to QCD and their limitations. Truncation schemes for DSEs of QCD are
discussed in the axial gauge and in the Landau gauge. We review the available
results from a systematic non-perturbative expansion scheme established for
Landau gauge QCD. Comparisons to related lattice results, where available, are
presented.
  The applications of QCD Green's functions to hadron physics are summarized.
Properties of ground state mesons are discussed on the basis of the
Bethe-Salpeter equation for quarks and antiquarks. The Goldstone nature of
pseudoscalar mesons and mechanisms of diquark confinement are reviewed. We
discuss some properties of ground state baryons based on their description as
Bethe-Salpeter/Faddeev bound states of quark-diquark correlations in the
quantum field theory of confined quarks and gluons.


title: Diagonalization of the strongly coupled lattice QCD Hamiltonian

abstract:
  We construct a solution to the equation of motion of Hamiltonian lattice QCD
in the strong coupling limit using Wilson fermions which exactly diagonalizes
the Hamiltonian to second order in the field operators. This solution obeys the
free lattice Dirac equation with a dynamical mass which is identified with the
gap. The equation determining this gap is derived and it is found that the
dynamical quark mass is a constant to lowest order in N_c but becomes momentum
dependent once 1/N_c corrections are taken into account. We interpret our
solution within the framework of the N-quantum approach to quantum field theory
and discuss how our formalism may be systematically extended to study bound
states at finite temperature and chemical potential.


title: Exact and Truncated Dynamics in Nonequilibrium Field Theory

abstract:
  Nonperturbative dynamics of quantum fields out of equilibrium is often
described by the time evolution of a hierarchy of correlation functions, using
approximation methods such as Hartree, large N, and nPI-effective action
techniques. These truncation schemes can be implemented equally well in a
classical statistical system, where results can be tested by comparison with
the complete nonlinear evolution obtained by numerical methods. For a 1+1
dimensional scalar field we find that the early-time behaviour is reproduced
qualitatively by the Hartree dynamics. The inclusion of direct scattering
improves this to the quantitative level. We show that the emergence of
nonthermal temperature profiles at intermediate times can be understood in
terms of the fixed points of the evolution equations in the Hartree
approximation. The form of the profile depends explicitly on the initial
ensemble. While the truncated evolution equations do not seem to be able to get
away from the fixed point, the full nonlinear evolution shows thermalization
with a (surprisingly) slow relaxation.


title: Polarization Phenomena by Deuteron Fragmentation into Pions

abstract:
  The fragmentation of deuterons into pions emitted forward in the kinematic
region forbidden for free nucleon-nucleon collisions is analyzed. The inclusive
relativistic invariant spectrum of pions and the tensor analyzing power T_{20}
are investigated within the framework of an impulse approximation using
different kinds of the deuteron wave function. The influence of P-wave
inclusion in the deuteron wave function is studied, too. The invariant spectrum
is shown to be more sensitive to the amplitude of the $NN \to \pi X$ process
than the tensor analyzing power T_{20}. It is shown that the inclusion of the
non-nucleon degrees of freedom in a deuteron results a satisfactory description
of experimental data about the inclusive pion spectrum and improves the
description of data about T_{20}. According to the experimental data, T_{20}
has the positive sign and very small values, less than 0.2, what contradicts to
the theoretical calculations ignoring these degrees of freedom.


title:
Soft diffraction and the elastic slope at Tevatron and LHC energies: a
  multi-Pomeron approach

abstract:
  We present a formalism for high energy soft processes, mediated by Pomerons,
which embodies pion-loop insertions in the Pomeron trajectory, rescattering
effects via a two-channel eikonal and high-mass diffractive dissociation. It
describes all the main features of the data throughout the ISR to Tevatron
energy interval. We give predictions for soft diffractive phenomena at the LHC
energy, and we calculate the different survival probabilities of rapidity gaps
which occur in various diffractive processes.


title:
Implications of a Low sin(2 beta): A Strategy for Exploring New Flavor
  Physics

abstract:
  We explore the would-be consequences of a low value of the CP-violating phase
$\sin2\beta_{\psi K}$. The importance of a reference triangle obtained from
measurements that are independent of $B$--$\bar B$ and $K$--$\bar K$ mixing is
stressed. It can be used to extract separately potential New Physics
contributions to mixing in the $B_d$, $B_s$ and $K$ systems. We discuss several
constructions of this triangle, which will be feasible in the near future. The
discrete ambiguity is at most two-fold and eventually can be completely
removed. Simultaneously, it will be possible to probe for New Physics in
loop-dominated rare decays.


title: Gluons in the QCD bound state problem - a way to exact solution

abstract:
  The colored objects -- quarks and gluons -- being confined in a small volume
$V\sim R_0^3,$ $R_0\sim 0.5$fm inside the QCD bound state get there not small
masses $m_{q\bar q}\sim 1$GeV, $m_g\sim 0.5$GeV. This drastically simplifies
the QCD dynamics, as now the probabilities e.g. of production of one extra
massive valent gluon or extra $q\bar q$ pair, turned to be small due to a large
gap between corresponding energy levels. The ordinary quantum mechanical
perturbation theory calculations made in the paper shows that corresponding
dimensionless transition amplitudes
$\Lambda_{MH}=\frac{V_{MH}}{|E^{(0)}_M-E^{(0)}_H|}$ (from meson $q\bar q$ to
the hybrid $q\bar qg$) have a value of 20--25% and the mixing of hybrid with
glueball $(gg)$ is even smaller (of the order of 10--18%). Taking into account
all such mixings with all highly lying Fock states is equivalent to the exact
solution of QCD bound state problem. This can be done really summing the small
perturbation theory results for these states contributions.


title: Improved Approximations for the Three-Loop Splitting Functions in QCD

abstract:
  We update our approximate parametrizations of the three-loop splitting
functions for the evolution of unpolarized parton densities in perturbative
QCD. The new information taken into account is given by the additional Mellin
moments recently calculated by Retey and Vermaseren. The inclusion of these
constraints reduces the uncertainties of our approximations considerably and
extends their region of applicability by about one order of magnitude to lower
momentum fractions x .


title: Higgs production at hadron colliders as a probe of new physics

abstract:
  The coupling of Higgs with gauge bosons can receive non-decoupling
corrections due to heavy quanta. Deviation from the SM predictions are
described by a set of parameters e_V, which can be related to the parameters
S,T. The Higgs production by gluon fusion can be used to probe e_g, whereas its
decays into WW can probe e_W. The resulting bounds may imply the exclusion of
heavy particles, such as additional standard or mirror families, chiral colored
sextets and octet quarks. Within the MSSM, we also find that gluon fusion is a
sensitive probe for the spectrum of squark masses.


title: Nonperturbative Techniques for QED Bound States

abstract:
  Advantages of using a low-energy effective theory to study bound state
properties are briefly discussed, and a nonperturbative implementation of such
an effective theory is described within the context of nonrelativistic quantum
mechanics. The hydrogen atom, in the approximation of a structureless,
infinite-mass nucleus, but with the leading relativistic and radiative
corrections included, is used to demonstrate the construction and solution of
the effective theory. The resulting Hamiltonian incorporates a finite
ultraviolet cutoff and can be solved nonperturbatively. An appendix lists
explicit formulae for the various matrix elements necessary to diagonalize the
Hamiltonian using gaussian basis sets.


title: Constituent quark masses from a modified perturbative QCD

abstract:
  A recently proposed modified perturbative expansion for QCD incorporating
gluon condensation is employed to evaluate the quark and gluon self-energy
corrections in the first approximations. The results predict mass values of 1/3
of the nucleon mass for the light quarks u, d, and s and a monotonously growing
variation with the current mass. The only phenomenological input consists in
that <G^2> is evaluated up to order g^2 as a function of the unique parameter C
defining the modified propagator and then C is fixed to give a current estimate
of <g^2 G^2>. The light quarks u and d result to be confined and the s, c, b
and t ones show damped propagation modes, then suggesting a model for the large
differences in stability between the nucleons and the higher resonances. The
above properties of quark modes diverge from the fully confinement result
following from the similar gluon propagator previously considered by Munczek
and Nemirovski. On another hand, the condensate effects on the gluon
self-energy furnish a tachionic mass shell as predicted by the Fukuda analysis
of gluon condensation in QCD.


title: Implications of the possibility that sin(2 beta) is small

abstract:
  Recently, the Babar and Belle collaborations have reported their first
measurements of the CP-violating asymmetry in Bd --> psi KS, and more precise
results will follow soon. We discuss what a future evidence for small sin(2
beta) could mean, contrasting the usual possibility of new physics in the Bd
system, with the interesting alternative that the new physics effects are
confined to the kaon system.


title: NLO evolution kernels for skewed transversity distributions

abstract:
  We present a calculation of the two-loop evolution kernels of the twist-two
transversally polarized quark and linearly polarized gluon skewed parton
distributions in the minimal subtraction scheme and discuss a solution of the
evolution equations suitable for numerical implementations.


title: One-loop Reggeon-Reggeon-gluon vertex at arbitrary space-time dimension

abstract:
  In order to check the compatibility of the gluon Reggeization in QCD with the
$s$-channel unitarity, the one-loop correction to the Reggeon-Reggeon-gluon
vertex must be known at arbitrary space-time dimension $D$. We obtain this
correction from the gluon production amplitude in the multi-Regge kinematics
and present an explicit expression for it in terms of a few integrals over the
transverse momenta of virtual particles. The one-gluon contribution to the
non-forward BFKL kernel at arbitrary $D$ is also obtained.


title: QCD Calculations of Heavy Quarkonium States

abstract:
  Recent results on the QCD analysis of bound states of heavy $\bar{q}q$ quarks
are reviewed, paying attention to what can be derived from the theory with a
reasonable degree of rigour. We report a calculation of $\bar{b}c$ bound
states; a very precise evaluation of $b, c$ quark masses from quarkonium
spectrum; the NNLO evaluation of $\Upsilon\to e^+e^-$; and a discussion of
power corrections. For the $b$ quark {\sl pole} mass we get, including
$O(m_c^2/m_b^2)$ and $O(\alpha_s^5\log \alpha_s)$ corrections,
$m_b=5.020\pm0.058 GeV$; and for the $\bar{MS}$ mass the result, correct to
$O(\alpha_s^3)$, $O(m_c^2/m_b^2)$, $\bar{m}_b(\bar{m}_b)=4.286\pm0.036 GeV$.
For the decay $\Upsilon\to e^+e^-$, higher corrections are too large to permit
a reliable calculation, but we can predict a toponium width of $13\pm1 keV$.


title:
Remarks on the Calculation of the Enhancement Factor in the K -> 2 pion
  Decay

abstract:
  The problem of calculation of the enhancement factor due to the strong pion
final state interaction is reexamined in the light of recent interest in
understanding of the origine of the $\Delta I=1/2$ rule and calculations of the
CP violation parameter $\epsilon^{\prime}/\epsilon$. It is shown that the
traditional method of calculating the \emph{absolute} enhancement factor is
model dependent, while the method of relating $K \to 2\pi$ amplitude to the
$K-\pi$ matrix element using Current Algebra is on a safer ground.


title: Implications of a Small CP Asymmetry in B->\psi K_S

abstract:
  New measurements of the CP asymmetry in B->\psi K_S, a_{\psi K_S}, by the
BABAR and BELLE collaborations are consistent with the Standard Model
prediction for sin2\beta. These measurements, however, leave open the
possibility that a_{\psi K_S} is well below the Standard Model prediction. We
identify deviations from the `reasonable ranges' of hadronic parameters that
can lead to low values of sin2\beta. New physics, mainly in B^0-\barB^0 mixing
and/or K^0-\barK^0 mixing, can explain low values of a_{\psi K_S} in two ways:
either by allowing for values of sin2\beta below the Standard Model prediction
or by modifying the relation between a_{\psi K_S} and sin2\beta.


title:
Neutrino masses and mixing with seesaw mechanism and universal breaking
  of extended democracy

abstract:
  In the framework of a minimal extension of the SM, where the only additional
fields are three right-handed neutrinos, we suggest that the charged lepton,
the Dirac neutrino and the right-handed Majorana neutrino mass matrices are
all, to leading approximation, proportional to the democratic matrix. With the
further assumption that the breaking of this extended democracy is universal
for all leptonic mass matrices, a large mixing in the 2-3 sector can be
obtained and is linked to the seesaw mechanism, together with the existence of
a strong hierarchy in the masses of right-handed neutrinos. The structure of
the resulting effective mass matrix of light neutrinos is stable against the
RGE evolution, and a good fit to all solar and atmospheric neutrino data is
obtained.


title: Az elektrogyenge f\'azis\'atmenet (The electroweak phase transition)

abstract:
  The electroweak phase transition provides the most attractive framework to
account for the baryon asymmetry of the universe. Comparing results of
perturbative and nonperturbative studies is not straightforward, however, due
to the different coupling constant definitions. The perturbative one stems from
the $\bar{\mathrm{MS}}$ subtraction scheme, while the nonperturbative one uses
the static quark potential. The momentum-space perturbative static potential is
calculated in the SU(2)--Higgs model, and is Fourier transformed into
coordinate space. Based on the connection between the coupling constants,
two-loop perturbative and 4-dimensional lattice simulation results are
contrasted. The thermodynamical parameters of the phase transition indicate
that perturbative results are reliable only for low Higgs masses, far from the
endpoint. The value of the endpoint can be refined to $72.1\pm1.4$ GeV. The
Higgs mass range for which dimensional reduction yields reliable results is
identified. As an extension of the standard model, the MSSM is also studied.
Some useful trends are indicated by a simple one-loop perturbative approach:
baryogenesis requirements are more easily met if the stop is lighter thanthe
top; colour-breaking phase transition may be possible, etc. In order to perform
4D nonperturbative studies the supercomputer PMS was built at E\"otv\"os
University. The results and the techniques of the simulations of the bosonic
sector of the MSSM performed on PMS are presented. A phase diagram is given,
the bubble wall is studied. The cosmologically relevant part of the parameter
space is analysed. The results show that baryogenesis is possible within the
MSSM if $m_h\leq 103\pm 4$ GeV.


title:
Day-night asymmetry of high and low energy solar neutrino events in
  Super-Kamiokande and in the Sudbury Neutrino Observatory

abstract:
  In the context of solar neutrino oscillations among active states, we briefly
discuss the current likelihood of Mikheyev-Smirnov-Wolfenstein (MSW) solutions
to the solar neutrino problem, which appear to be currently favored at large
mixing, where small Earth regeneration effects might still be observable in
Super-Kamiokande (SK) and in the Sudbury Neutrino Observatory (SNO). We point
out that, since such effects are larger at high (low) solar neutrino energies
for high (low) values of the mass square difference \delta m^2, it may be
useful to split the night-day rate asymmetry in two separate energy ranges. We
show that the difference \Delta of the night-day asymmetry at high and low
energy may help to discriminate the two large-mixing solutions at low and high
\delta m^2 through a sign test, both in SK and in SNO, provided that the
sensitivity to \Delta can reach the (sub)percent level.


title:
Overview of Grand Unified Models and Their Predictions for Neutrino
  Oscillations

abstract:
  A brief overview of Grand Unified Models is presented with some attention
paid to their predictions for neutrino oscillations. Given the well-known
features of the two non-unified standard models, SM and MSSM, a listing of the
features of classes of unified models is given, where a GUT flavor symmetry
and/or family symmetry are introduced to reduce the number of model parameters.
Some general remarks are then made concerning the type of predictions that
follow for the neutrino masses and mixings.


title: Attractive Forces Between Global Monopoles and Domain Walls

abstract:
  We study the interaction between stable monopoles and domain walls in a
$SO(3) \times Z(2)$ scalar field theory. Numerical simulations reveal that
there is an attractive force between the monopole and the wall, but that after
the monopole and the wall collide, the monopole does not unwind. We present an
analytic explanation for the origin of the attractive force, and conclude that
this is a generic feature of monopole-wall interactions which does not depend
on the detailed structure of the model. The existence of the attractive force
supports the hypothesis of Dvali {\em et al.} (hep-ph/9710301), who proposed
that monopoles can be ``swept up'' by domain walls, thereby alleviating or
solving the monopole problem associated with phase transitions occurring after
or in the absence of inflation.


title: Deeply Virtual Compton Scattering and Skewed Parton Distribution

abstract:
  An overview of the current status of and possible future theoretical,
phenomenological and experimental studies of DVCS and SPD's is presented.


title:
A Comparison of the Physics Potential of Future Long Baseline Neutrino
  Oscillation Experiments

abstract:
  We compare the generic physics potential of various combinations of
conventional Wide Band or Neutrino Factory Beams with different detectors to
determine several oscillation parameters in long baseline experiments. For each
combination of beam and detector we show the precision which can be obtained
for the leading oscillation parameters $\dm{31}$ and $\sin^2 2\theta_{23}$.
Furthermore we show the sensitivity to $\sin^2 2\theta_{13}$ and the range in
$\sin^2 2\theta_{13}$ for which the sign of $\dm{31}$ can be extracted via
matter effects. The results suggest that existing conventional Wide Band Beam
and detector technology can be used to considerably improve the precision of
neutrino properties until a neutrino factory will be built.


title: B_{c} meson and the light-heavy quarkonium spectrum

abstract:
  We compute the c \bar{b} spectrum from a first principle Salpeter equation
obtained in a preceding paper. For comparison we report also the heavy-light
quarkonium spectrum and the hyperfine separations previously presented only in
a graphical form. Notice that all results are parameter free.


title:
Possible Implications of Small or Large CP Violation in B^0_d vs
  \bar{B}^0_d --> J/\psi K_S Decays

abstract:
  We argue that a small or large CP-violating asymmetry {\cal A}_{\psi K_S} in
B^0_d vs \bar{B}^0_d --> J/\psi K_S decays, which seems to be favored by the
recent BaBar or Belle data, might hint at the existence of new physics in B^0_d
- \bar{B}^0_d mixing. We present a model-independent framework to show how new
physics in B^0_d - \bar{B}^0_d mixing modifies the standard-model CP-violating
asymmetry {\cal A}^{\rm SM}_{\psi K_S}. We particularly emphasize that an
experimental confirmation of {\cal A}_{\psi K_S} \approx {\cal A}^{\rm
SM}_{\psi K_S} must not imply the absence of new physics in B^0_d - \bar{B}^0_d
mixing.


title: Fate of the Sterile Neutrino

abstract:
  In light of recent Super-Kamiokande data and global fits that seem to exclude
both pure \nu_\mu \to \nu_s oscillations of atmospheric neutrinos and pure
\nu_e \to \nu_s oscillations of solar neutrinos (where \nu_s is a sterile
neutrino), we reconsider four-neutrino models to explain the LSND, atmospheric,
and solar neutrino oscillation indications. We argue that the solar data, with
the exception of the ^{37}Cl results, are suggestive of \nu_e \to \nu_s
oscillations that average to a probability of approximately 1/2. In this
interpretation, with two pairs of nearly degenerate mass eigenstates separated
by order 1 eV, the day-night asymmetry, seasonal dependence, and energy
dependence for ^8B neutrinos should be small. Alternatively, we find that
four-neutrino models with one mass eigenstate widely separated from the others
(and with small sterile mixings to active neutrinos) may now be acceptable in
light of recently updated LSND results; the ^{37}Cl data can be accommodated in
this model. For each scenario, we present simple four-neutrino mixing matrices
that fit the stated criterion and discuss future tests.


title: Seesaw model with softly broken L_e - L_\mu - L_\tau

abstract:
  We enlarge the lepton sector of the Standard Model by adding to it two
right-handed neutrino singlets, and propose a model based on the seesaw
mechanism and on the lepton number $\bar L = L_e - L_\mu - L_\tau$. The model
is innovative from the theoretical point of view in that the $\bar L$-invariant
mass term of the right-handed neutrinos is associated with the large mass scale
responsible for the seesaw mechanism, whereas $\bar L$ is softly broken at a
smaller scale by the remaining Majorana mass terms of the right-handed
neutrinos. While being very economical, the model has predictive power: one
neutrino is massless ($m_3 = 0$), the lepton mixing matrix $U$ features $U_{e3}
= 0$, and the solar-neutrino oscillations have maximal amplitude.


title:
Using kaon regeneration to probe the quark mixing parameter cos(2 beta)
  in B --> psi K decays

abstract:
  We suggest a novel method to determine the sign of cos(2 beta) in the decays
B --> psi K, by creating interference between KL and KS final states via
``regeneration,'' that is propagation through a matter target region to convert
some KL to KS. The determination of this quantity resolves an ambiguity between
beta and (90o - beta) that remains after the standard measurements of sin(2
beta) and may turn out to be important in resolving whether the result is in
agreement with Standard Model predictions or indicates the presence of new
physics. We find the measurement is feasible at a B-factory, but requires
several years of high-luminosity running with a regeneration target affecting a
significant fraction of the detector.


title: The Lower Bound on the Neutralino-Nucleon Cross Section

abstract:
  We examine if there is a lower bound on the direct detection cross section
for the neutralino dark matter in the MSSM. If we impose the minimal
supergravity boundary conditions as well as the "naturalness" condition, in
particular m_{1/2} < 300 GeV, we show that there is a lower bound of
10^{-46}cm^2 on the cross section for neutralino scattering off of a proton. We
also clarify the origin for the lower bound. Relaxing either of the
assumptions, however, can lead to much smaller cross sections.


title:
Do electroweak precision data and Higgs-mass constraints rule out a
  scalar bottom quark with mass of O(5 GeV)?

abstract:
  We investigate the phenomenological implications of a light scalar bottom
quark, with a mass of about the bottom quark mass, within the minimal
supersymmetric standard model. The study of such a scenario is of theoretical
interest, since, depending on their production and decay modes, light sbottoms
may have escaped experimental detection up to now and, in addition, may
naturally appear for large values of \tan\beta. In this article we show that
such a light sbottom cannot be ruled out by the constraints from the
electroweak precision data and the present bound on the lightest CP-even Higgs
boson mass at LEP. It is inferred that a light sbottom scenario requires in
general a relatively light scalar top quark whose mass is typically about the
top-quark mass. It is also shown that under these conditions the lightest
CP-even Higgs boson decays predominantly into scalar bottom quarks in most of
the parameter space and that its mass is restricted to m_h ~< 123 GeV.


title: Schematic Method for Estimation of CP Asymmetry in Neutrino Oscillation

abstract:
  Within the framework of three generations of leptons the schematical method
for estimating CP asymmetry in neutrino oscillations is considered. We
introduce a unitarity triangle corresponding to \nu_e-\nu_{\mu} oscillation, in
addition, we show that it is convenient for the estimation to define another
new triangle. CP asymmetry is determined by the difference between the shapes
of a unitarity triangle and new triangle. As results, (i) we show that CP
asymmetry becomes maximal if the shapes of these two triangles are the same.
(ii) We can easily estimate L/E which leads almost 100% asymmetry using this.
(iii) In \nu_e-\nu_{\mu} oscillation with \sin^2 2\theta_{13} \simeq 0.04, we
obtain about 90% asymmetry for LMA MSW scenario and 3% asymmetry for SMA MSW
scenario within long baseline neutrino expriments to be realized in near
future.


title: Quantum tunneling in thermal medium

abstract:
  Time evolution of tunneling phenomena in medium is studied using a standard
model of environment interaction. A semiclassical formula valid at low, but
finite temperatures is derived in the form of integral transform for the
reduced Wigner function, and the tunneling probability in thermal medium is
calculated for a general tunneling potential of one dimensional system. Effect
of dissipation, its time evolution in particular, depends on the behavior of
the potential far beyond the barrier.


title:
Correspondence of consistent and inconsistent spin-3/2 couplings via the
  equivalence theorem

abstract:
  The Rarita-Schwinger theory of free massive spin-3/2 field obeys the physical
degrees of freedom counting, and one can distinguish ``consistent'' couplings
which maintain this property and ``inconsistent'' couplings which destroy it.
We show how one can obtain consistent couplings from inconsistent ones by a
redefinition of the spin-3/2 field. The field redefinition gives rise to
additional ``contact terms'' which, via the equivalence theorem, can be
associated with the contribution of the extra lower-spin degrees of freedom
involved by the inconsistent coupling.


title: Three Loop Free Energy Using Screened Perturbation Theory

abstract:
  The conventional weak-coupling expansion for the pressure of a hot plasma
shows no sign of convergence unless the the coupling constant $g$ is tiny. In
this talk, I discuss screened perturbation theory (SPT) which is a
reorganization of the perturbative expansion by adding and subtracting a local
mass term in the Lagrangian. We consider several different mass prescriptions,
and compute the pressure to three-loop order. The SPT-improved approximations
appear to converge for rather large values of the coupling constant.


title: Massive field contributions to the QCD vacuum tunneling amplitude

abstract:
  For the one-loop contribution to the QCD vacuum tunneling amplitude by quarks
of generic mass value, we make use of a calculational scheme exploiting a large
mass expansion together with a small mass expansion. The large mass expansion
for the effective action is given by a series involving higher-order
Seeley-DeWitt coefficients, and we carry this expansion up to order
$1/(m\rho)^8$, where $m$ denotes mass of the quark and $\rho$ the instanton
size parameter. For the small mass expansion, we use the known exact expression
for the particle propagation functions in an instanton background and evaluate
explicitly the effective action to order $(m\rho)^2$. A smooth interpolation of
the results from both expansions suggests that the quark contribution to the
instanton tunneling amplitude have a relatively simple $m\rho$-dependent
behavior.


title:
Complete analysis on the next-to-leading order supersymmetric QCD
  corrections to $B^0-\bar{B}^0$ mixing

abstract:
  We present a complete next-to-leading-order calculation of the QCD
corrections to $B^0-\bar{B}^0$ ($K^0-\bar{K}^0$) mixing in the framework of the
minimal flavor violating (MFV) supersymmetry. We take into account the
contributions from the gluino and find that the gluino-mediated corrections
modify the LO result obviously even when the mass of gluino $m_{\tilde{g}} \gg
m_{\rm w}$. In general, one cannot neglect gluino contributions.


title: A variational study of bound states in the Higgs model

abstract:
  The possible existence of Higgs-Higgs bound states in the Higgs sector of the
Standard Model is explored using the |hh>+|hhh> variational ansatz of Di Leo
and Darewych. The resulting integral equations can be decoupled exactly,
yielding a one-dimensional integral equation, solved numerically. We thereby
avoid the extra approximations employed by Di Leo and Darewych, and we find a
qualitatively different mass renormalization. Within the conventional scenario,
where a not-too-large cutoff is invoked to avoid "triviality", we find, as
usual, an upperbound on the Higgs mass. Bound-state solutions are only found in
the very strong coupling regime, but at the same time a relatively small
physical mass is required as a consequence of renormalization.


title: Gluon condensates at finite temperature

abstract:
  We consider various special cases of gluon condensates at finite temperature.
The gluon condensate for an ideal gas of gluons with a given vacuum expectation
value is introduced for the sake of comparison with that calculated using the
recent finite temperature lattice gauge simulations for a pure Yang-Mills SU(3)
gauge theory at the known critical temperature. We extend this comparison using
the high precision lattice data for two light dynamical quarks. The
investigation of these three cases show some interesting differences arising
from the strong interaction alone and in the presence of quarks. In this
context we discuss some newer simulations for heavier quarks and other
properties related to gluon condensation.


title: Can Neutrinos Probe Extra Dimensions?

abstract:
  We conjecture that the topological structure of the gauge symmetries required
by the Calabi-Yau vacuum and the dualities in string/D-branes considered in the
world with some additional dimensions can lead to an extension of the main
principles of the Special Theory of Relativity. The link between the
topological structure of the vacuum and the, hierarchy of the gauge symmetries
could be checked by the existence of the ``almost massless'', ''sterile''
particles. These particles could have flying properties different from the
standard predictions of the STR. It is natural to consider this property for
neutrinos, known up to now ``$U(1)_{em}$ sterile'' particles. Here we discuss
two such effects depending on the possible existence of large and/or small
extra dimensions and what is the maximal speed for both cases.
  The effect of large extra dimensions can be directly connected with the
existence of a hidden boost, $c_{hid} >> c_{em}$, excited by new global
dimensions and can lead to the monotonous rise of the neutrino velocity at high
energies, $v_{\nu} > c$.
  The effect of small extra dimensions, universal with respect to all
particles, can be connected with the gravitation recoils of the propagation of
neutrino in the space-time vacuum-foam and it leads to the effect of
diminishing the neutrino velocity at high energies.
  We propose to check these conjectures for neutrinos of different energies and
species. Limits for existing neutrino data and expected sensitivities of
possible experiments for accelerator - produced neutrinos are considered. It is
pointed out that CERN has the unique opportunity of measuring the indicated
effects.


title:
Precise Predictions for Four-Fermion Production in Electron-Positron
  Annihilation

abstract:
  The complete O(alpha) electroweak radiative corrections to e+e- --> WW --> 4f
in the electroweak Standard Model are presented in the double-pole
approximation. We give analytical and numerical results for the
non-factorizable corrections and express the factorizable virtual corrections
in terms of the known corrections to on-shell W-pair production and W decay.
The full matrix elements to the lowest order processes e+e- --> 4f+gamma are
taken into account for the real corrections. The matching of soft and collinear
singularities between virtual and real corrections is done using the
subtraction method. A Monte Carlo generator is constructed which corresponds to
the subtraction branch of RacoonWW. Various numerical results are presented.


title:
Bethe-Salpeter Approach for the $P_{33}$ Elastic Pion-Nucleon Scattering
  in Heavy Baryon Chiral Perturbation Theory

abstract:
  Heavy Baryon Chiral Perturbation Theory (HBChPT) to leading order provides a
kernel to solve the Bethe-Salpeter equation for the $P_{33}$
($\Delta(1232)$-channel) $\pi-N$ system, in the infinite nucleon mass limit.
Crossed Born terms include, when iterated within the Bethe-Salpeter equation,
both {\it all} one- and {\it some} two-pion intermediate states, hence
preserving elastic unitarity below the two-pion production threshold. This
suggests searching for a solution with the help of dispersion relations and
suitable subtraction constants, when all in-elasticities are explicitly
neglected. The solution allows for a successful description of the experimental
phase shift from threshold up to $\sqrt{s}=1500$ MeV in terms of four
subtraction constants. Next-to-leading order HBChPT calculations are also used
to estimate the unknown subtraction constants which appear in the solution.
Large discrepancies are encountered which can be traced to the slow convergence
rate of HBChPT.


title:
Possible violation of Newtonian gravitational law at small distances and
  constraints on it from the Casimir effect

abstract:
  The recent ideas that the gravitational and gauge interactions become united
at the weak scale lead to Yukawa-type corrections to the Newtonian
gravitational law at small distances. We briefly summarize the best constraints
on these corrections obtained recently from the experiments on the measurement
of the Casimir force. The new constraints on the Yukawa-type interaction are
derived from the latest Casimir force measurement between a large gold coated
sphere and flat disk using an atomic force microscope. The obtained constraints
are stronger up to 19 times comparing the previous experiment with aluminum
surfaces and up to 4500 times comparing the Casimir force measurements between
dielectrics. The application range of constraints obtained by means of an
atomic force microscope is extended.


title: Critical coupling for chiral symmetry breaking in QCD motivated models

abstract:
  We determine the critical coupling constant above which dynamical chiral
symmetry breaking occurs in a class of QCD motivated models where the gluon
propagator has an enhanced infrared behavior. Using methods of bifurcation
theory we find that the critical value of the coupling constant is always
smaller than the one obtained for QCD.


title: New Physics Beyond the Standard Model at $\gamma \gamma$ Colliders

abstract:
  The complementarity of $e^+e^-$ and $\gamma \gamma$ colliders to discover and
explore new physics beyond the Standard Model(SM) is discussed. After briefly
surveying a number of various new physics scenarios we concentrate in detail on
signatures for Large Extra Dimensions via the process $\gamma \gamma \to WW$.


title: The Theory of the Nucleon Spin

abstract:
  I discuss two topics of current interest in the study of the spin structure
of the nucleon. First, I discuss whether there is a sum rule for the components
of the nucleon's angular moments. Second, I discuss the measurement of the
nucleon's transversity distribution in light of recent results reported by the
HERMES collaboration at DESY.


title: Baryon mass spectra with QCD- type screened potential

abstract:
  The work is devoted to the description of baryon mass spectrum in the
quasy-relativistic quark potential model. For cosidering 3 - quark system
advantageous is the use of hyperspherical functions. For obtaining the mass -
seguence of $\Delta_{33}-$isobar the numerical computations were carryed out
with the use of screened QCD - motivated potential, the use of which gives
quite acceptable results even in the nonrelativistic approximation.


title: Quantum Phase Transitions and the Extended Coupled Cluster Method

abstract:
  We discuss the application of an extended version of the coupled cluster
method to systems exhibiting a quantum phase transition. We use the lattice
O(4) non-linear sigma model in (1+1)- and (3+1)-dimensions as an example. We
show how simple predictions get modified, leading to the absence of a phase
transition in (1+1) dimensions, and strong indications for a phase transition
in (3+1) dimensions.


title: Affleck-Dine Leptogenesis with an Ultralight Neutrino

abstract:
  We perform a detailed analysis on Affleck-Dine leptogenesis taking into
account the thermal effects on the dynamics of the flat direction field $\phi$.
We find that an extremely small mass for the lightest neutrino $\nu_1$,
${m_\nu}_1\lsim 10^{-8}$ eV, is required to produce enough lepton-number
asymmetry to explain the baryon asymmetry in the present universe. We impose
here the reheating temperature after inflation $T_R$ to be $T_R\lsim 10^8$ GeV
to solve the cosmological gravitino problem. The required value of neutrino
mass seems to be very unlikely the case since the recent Superkamiokande
experiments suggest the masses of heavier two neutrinos $\nu_2$ and $\nu_3$ to
be in a range of $10^{-1}$--$10^{-3}$ eV. We also propose a model to avoid this
difficulty based on the Peccei-Quinn symmetry, where the required neutrino mass
can be as large as ${m_\nu}_1\simeq 10^{-4}$ eV.


title:
Implications of radion-higgs couplings for high energy scattering in the
  Randall-Sundrum model

abstract:
  In this report we derive the couplings of the Randall-Sundrum radion to the
standard model higgs boson. We then use these couplings to determine the J=0
partial wave amplitude for the process $hh\to h\phi $. We find that at very
high energies (i.e. $s\gg m_h^2, \mp^2$) the s wave partial wave unitarity is
violated if $m_h>m_c\approx \sqrt{16\pi\vphi v}$ where $\vphi$ is the radion
vev. Interestingly this bound is independent of the radion mass to the leading
order. We also consider the high energy behaviour of the transition amplitudes
for some other processes in the RS scenario and compare them with their SM
behaviour.


title: Consistent OPE Description of Gluon Two- and Three-point Green Function?

abstract:
  We perform an OPE analysis of the flavorless non-perturbative gluon
propagator and the symmetric three-gluon vertex in the Landau gauge. The first
subdominant operator is $A_\mu A^\mu$ which can condensate in the Landau gauge
``vacuum'' although being a non-gauge invariant operator. We neglect all higher
dimension operators. Then the gluon propagator and the symmetric three gluon
vertex only depend on one common unknown condensate. We propose a consistency
check from lattice data. At two loops for the leading coefficient and with
$1/p^2$ corrections at tree-level order the two fitted values for the
condensate do not agree. At three loops we argue that the today unknown
$\beta_2^{\rm MOM}$ should be equal to $1.5(3)\times \beta_2^{\widetilde{\rm
MOM}}=7400(1500)$ to fulfill the OPE relation. Inclusion of the power
corrections' anomalous dimensions should improve further the agreement. We show
that these techniques cannot be applied to the asymmetric three gluon vertex
with one vanishing momentum.


title:
Cancellations in Neutrinoless Double Beta Decay and the Neutrino Mass
  Matrix

abstract:
  In a degenerate scheme with mass m_0 a complete analysis of the allowed range
of the effective electron neutrino Majorana mass <m> is performed. Special
attention is paid to effects of cancellations caused either by intrinsic CP
parities of the eigenstates (CP invariance) or by complex mixing matrix
elements (CP violation). We investigate all possibilities and give in each case
constraints on the phases, the relative CP parities or the neutrino mass scale.
A solar mixing angle \sin^2 2 \theta smaller than 0.7 jeopardizes the
degenerate mass scheme. A key value of <m>/m_0 is identified, which is
independent on the solar solution and would rule out certain schemes. Also it
would answer the question regarding the presence of CP violation. Even if a
total neutrino mass scale and an effective mass is measured, the value of the
phases or parities is not fixed, unless in some special cases. The resulting
uncertainty in the other mass matrix elements is at least of the same order
than the one stemming from nuclear matrix elements calculations.


title: Excited Heavy Baryon Masses from the 1/N_c Expansion of HQET

abstract:
  The mass spectra of the L=1 orbitally excited heavy baryons with light quarks
in both the spin-flavor symmetric and the mixed representations are studied by
the $1/N_c$ expansion method in the framework of the heavy quark effective
theory. The mixing effect between the baryons in the two representations is
also considered. The general pattern of the spectrum is predicted which will be
verified by the experiments in the near future.


title: $B^0_{d,s}\to \mu^-\mu^+$ in the MSSM

abstract:
  We present the results of the complete one-loop computation of the
$B^0_{d,s}\to l^+l^-$ decay rate in the MSSM. Both sources of the FCNC, the CKM
matrix and off-diagonal entries of the sfermion mass matrices are considered.
Strong enhancement of the branching ratio (compared to the SM prediction) can
be obtained in the large $\tan\beta\sim m_t/m_b$ regime in which the neutral
Higgs boson ``penguin'' diagrams dominate. We make explicit the strong
dependence of this enhancement on the top squarks mixing angle in the case of
the chargino contribution and on the $\mu$ parameter in the case of the gluino
contribution. We show that, in some regions of the MSSM parametre space, the
branching ratio for this process can be as large as $10^{-(5-4)}$ respecting
all existing constraints, including the CLEO measurement of $BR(B\to
X_s\gamma)$. We also estimate, that for chargino and stop masses $\sim{\cal
O}(100$ GeV) $BR(B^0_s\to l^+l^{\prime -})$ with $ll^\prime=e\tau$ or $\mu\tau$
can be of the order of $10^{-11}$ for the still allowed values of the
off-diagonal entries in the slepton mass matrix.


title: The Fractal Geometry of Critical Systems

abstract:
  We investigate the geometry of a critical system undergoing a second order
thermal phase transition. Using a local description for the dynamics
characterizing the system at the critical point T=Tc, we reveal the formation
of clusters with fractal geometry, where the term cluster is used to describe
regions with a nonvanishing value of the order parameter. We show that,
treating the cluster as an open subsystem of the entire system, new
instanton-like configurations dominate the statistical mechanics of the
cluster. We study the dependence of the resulting fractal dimension on the
embedding dimension and the scaling properties (isothermal critical exponent)
of the system. Taking into account the finite size effects we are able to
calculate the size of the critical cluster in terms of the total size of the
system, the critical temperature and the effective coupling of the long
wavelength interaction at the critical point. We also show that the size of the
cluster has to be identified with the correlation length at criticality.
Finally, within the framework of the mean field approximation, we extend our
local considerations to obtain a global description of the system.


title: Intersections 2000: What's New in Hadron Physics

abstract:
  Hadron physics is that part of QCD dealing with hadron structure and vacuum
structure, almost all of which is nonperturbative in nature. Some of the open
problems in this field are outlined. We argue that hadron physics is a distinct
subfield, no longer within particle physics, and not at all the same as
classical nuclear physics. We believe that it needs to be better organized, and
that a first step in doing so might be to establish hadron physics as a new
division within the American Physical Society.


title: Solar neutrino oscillation from large extra dimensions

abstract:
  A plausible explanation for the existence of additional light sterile
neutrinos is that they correspond to modulini, fermionic partners of moduli,
which propagate in new large dimensions. We discuss the phenomenological
implications of such states and show that solar neutrino oscillation is well
described by small angle MSW oscillation to the tower of Kaluza Klein states
associated with the modulini. In the optimal case the recoil electron energy
spectrum agrees precisely with the measured one, in contrast to the single
sterile neutrino case which is disfavoured. We also consider how all
oscillation phenomena can be explained in a model including bulk neutrino
states. In particular, we show that a naturally maximal mixing for atmospheric
neutrinos can be easily obtained.


title: Neutrino Masses and Leptogenesis from R Parity Violation

abstract:
  In R parity violating supersymmetry (conserving baryon number B but violating
lepton number L), Majorana neutrino masses may arise at tree level, in one
loop, and in two loops. The L violating interactions work together with the B +
L violating electroweak sphalerons to erase any preexisting B or L asymmetry of
the Universe. To have successful leptogenesis nevertheless, a specific scenario
is proposed.


title:
Off-forward parton distributions and impact parameter dependent parton
  structure

abstract:
  The connection between parton distributions as a function of the impact
parameter and off-forward parton distributions is discussed in the limit of
vanishing skewedness parameter $\xi$, i.e. when the off-forwardness is purely
transverse. It is also illustrated how to relate $\xi\neq 0$ data to $\xi=0$
data, which is important for experimental measurements of these observables.


title: The Higgs masses and explicit CP violation in the gluino-axion model

abstract:
  In this work, we adress the phenomenological consequences of explicit CP
violation on direct Higgs-boson searches at high energy colliders. Having a
restricted parameter space, we concentrate on the recently proposed
gluino-axion model, and investigate the CP violation capability of the model
subject to the recent experimental data. It is shown that the Higgs masses as
well as their CP compositions are quite sensitive to the supersymmetric CP
phases. The lightest Higgs is found to be nearly CP even to a good
approximation whilst the remaining two heavy scalars do not have definite CP
parities.


title:
Resonance production in central pp collisions at the CERN Omega
  Spectrometer

abstract:
  A study of resonance production in central pp collisions is presented as a
function of several kinematical variables. In particular the difference in the
transverse momentum (dPT) of the exchanged particles shows that undisputed
qqbar mesons are suppressed at small dPT whereas glueball candidates are
enhanced and in addition, the azimuthal angle phi gives information on the
nature of the Pomeron.


title: Multiplicity distributions of quark and gluon jets in QCD

abstract:
  The solution of the equations for the generating functions of multiplicity
distributions of quark and gluon jets in higher order 3NLO perturbative QCD is
obtained. The non-perturbative effects are discussed as well. The results are
compared to recent experimental data on mean multiplicities, their ratio and
its slope, higher moments of the distributions.


title: A Field Theoretic Investigation of Spin in QCD

abstract:
  Utilizing the kinematical boost in light-front formalism one can address the
issue of relativistic spin operators in an arbitrary reference frame. In the
gauge $A^+=0$, the interaction dependent transverse spin operators can be
separated into three parts. In analogy with the helicity sum rule, we propose a
transverse spin sum rule. We perform a one loop renormalization of the
transverse spin operator and show that the counterterm needed is the same as
the linear mass counterterm in the light-front QCD Hamiltonian.


title: Neutrino Oscillation and CP Violation

abstract: We reconsider the meaning of observing CP violation in neutrino oscillation.


title: Strong Bootstrap Conditions

abstract:
  We reformulate the so-called ``strong bootstrap'' conditions for the gluon
Reggeization in the next-to-leading approximation (NLA), firstly suggested by
Braun and Vacca, using a different approach, which is not based on properties
of the eigenstates of the NLA octet BFKL kernel. We write the second strong
bootstrap condition for the NLA octet impact factors in a form which makes
clear their dependence on the process. According to this condition, the NLA
octet impact factors must be given by the product of the corresponding Reggeon
interaction vertices with a universal coefficient function. This function can
be used also in the formulation of the first strong bootstrap condition for the
NLA BFKL kernel in the octet state.


title: Some Issues in Flat Direction Baryogenesis

abstract:
  Motivated by recent developments, we explore some issues in Affleck-Dine
baryogenesis. We consider in greater detail the role of thermal effects in the
production of baryon number. We find that these effects are important even for
rather flat potentials, and obtain somewhat different estimates of the baryon
asymmetry than those in the literature. We also consider the decay of the
condensate, and possible implications of these observations for the formation
of Q-balls.


title: Non-factorizable effects in the $B-\bar B$ mixing

abstract:
  We analyse the corrections to factorization for the $B-\bar B$ mixing
amplitude assuming that non-factorizable soft gluon exchanges can be described
by the local gluon condensate. Within this approximation the $<\alpha_s
GG>$-correction to the mixing amplitude can be expressed through the $B$-meson
transition form factors at zero momentum transfer. The correction is negative
independent of the particular values of the form factors.
  As a next step, we study these form factors making use of the relativistic
dispersion approach based on the constituent quark picture. We obtain spectral
representations for the form factors in terms of the $B$-meson soft wave
function and the propagator of the color-octet $b\bar q$ system. The $B$-meson
wave function has been determined previously from weak exclusive B decays, so
the main uncertainty in our estimates comes from the unknown details of the
propagator in the nonperturbative region. We obtain $\Delta
B_{B_d}(m_b)=-0.06\pm 0.035 $ and $\Delta B_{B_s}(m_b)=-0.05\pm 0.03 $.


title: Theory of the nucleon spin-polarizabilities I

abstract:
  I summarize the theoretical predictions for the spin-dependent nucleon
polarizabilities based on chiral effective field theory approaches.


title:
Viable Supersymmetric Models with an Inverted Scalar Mass Hierarchy at
  the GUT Scale

abstract:
  Supersymmetric models with an inverted mass hierarchy (IMH: multi-TeV first
and second generation matter scalars, and sub-TeV third generation and Higgs
scalars) have been proposed to ameliorate phenomenological problems arising
from flavor changing neutral currents (FCNCs) and CP violating processes, while
satisfying conditions of naturalness. Models with an IMH already in place at
the GUT scale have been shown to be constrained in that for many model
parameter choices, the top squark squared mass is driven to negative values. We
delineate regions of parameter space where viable models with a GUT scale IMH
can be generated. We find that larger values of GUT scale first and second
generation scalar masses act to suppress third generation scalars, leading to
acceptable solutions if GUT scale gaugino masses are large enough. We show
examples of viable models and comment on their characteristic features. For
example, in these models the gluino mass is bounded from below, and effectively
decouples, whilst third generation scalars remain at sub-TeV levels. While
possibly fulfilling criteria of naturalness, these models present challenges
for detection at future pp and e^+e^- collider experiments.


title: Renormalons as dilatation modes in the functional space

abstract:
  There are two sources of the factorial large-order behavior of a typical
perturbative series. First, the number of the different Feynman diagrams may be
large; second, there are abnormally large diagrams known as renormalons. It is
well known that the large combinatorial number of diagrams is described by
instanton-type solutions of the classical equations. We demonstrate that from
the functional-integral viewpoint the renormalons do not correspond to a
particular configuration but manifest themselves as dilatation modes in the
functional space.


title:
Probing Neutral Gauge Boson Self-interactions in ZZ Production at Hadron
  Colliders

abstract:
  A detailed analysis of ZZ production at the upgraded Fermilab Tevatron and
the CERN Large Hadron Collider is presented for general ZZZ and ZZ\gamma
couplings. Deviations from the Standard Model gauge theory structure for each
of these can be parameterized in terms of two form factors which are severely
restricted by unitarity at high energy. Achievable limits on these couplings
are shown to be a dramatic improvement over the limits currently obtained by
e^+e^- experiments.


title:
Role of the Delta (1232) in DIS on polarized $^3$He and extraction of
  the neutron spin structure function $g_{1}^{n}(x,Q^2)$

abstract:
  We consider the effect of the transitions $n \to \Delta^{0}$ and $p \to
\Delta^{+}$ in deep inelastic scattering on polarized $^3$He on the extraction
of the neutron spin structure function $g_{1}^{n}(x,Q^2)$. Making the natural
assumption that these transitions are the dominant non-nucleonic contributions
to the renormalization of the axial vector coupling constant in the A=3 system,
we find that the effect of $\Delta$ increases $g_{1}^{n}(x,Q^2)$ by $10 \div
40$% in the range $0.05 \le x \le 0.6$, where our considerations are applicable
and most of the data for $g_{1}^{n}(x,Q^2)$ exist.


title: Azimuthal angular dependence of decay lepton in e+ e- --> t tbar

abstract:
  We discuss top quark production and its subsequent decay for searching new
physics at lepton colliders. The angular dependence of the decay leptons is
calculated including both QCD corrections and anomalous gamma Z - t tbar
couplings. The off-diagonal spin basis for the top and anti-top quarks is shown
to be useful to probe the anomalous couplings.


title: Isospin breaking exposed in f0(980)- a0(980) mixing

abstract:
  We suggest that mixing between the f0(980) and a0(980), due to their
dynamical interaction with the nearby KKbar thresholds, can give rise to a
significantly enhanced production rate of a0(980) relative to a2(1320) in pp ->
ps (eta pi0) pf as xF -> 0. The peaking of the cross section as phi -> 0 should
also occur. We show that such effects are seen in data and deduce that the
f0(980) - a0(980) mixing intensity is 8 +/- 3 %.


title: On the n -> 0 limit of gamma_gg(a) in QCD

abstract:
  We consider the n -> 0 limit of the DGLAP splitting function gamma_gg(a) at
all orders in the strong coupling constant, a, by analysing the leading order
large N_f form of the associated d-dimensional critical exponent. We show that
for unpolarized scattering the pole at n = 0 which appears in successive orders
in perturbation theory is absent in the resummed expression.


title: Generating QCD-antennas

abstract:
  An extension of the SARGE-algorithm of \cite{HKD} is introduced, which
includes the incoming momenta in the kinematical pole structure of the density
with which the momenta are generated. The algorithm is compared with RAMBO in
the integration of QCD-amplitudes in the SPHEL-approximation, and the computing
times are extrapolated to those for the calculation with exact matrix elements.


title: Kaluza-Klein Mediated Supersymmetry Breaking

abstract:
  We discuss a framework for communicating supersymmetry breaking to the
visible sector where the radius modulus, which determines the size of extra
dimensions, has an auxiliary vacuum expectation value. The modulus couplings
generate mass splitting in Kaluza-Klein supermultiplets and they act as
messengers of supersymmetry breaking. The soft masses are expressed in terms of
renormalization-group functions and the sparticle spectrum is determined by
what kind of field propagates in the bulk. This framework also provides new
possibilities for solving the supersymmetric flavor problem.


title:
Low-Scale and Gauge-Mediated Supersymmetry Breaking at the Fermilab
  Tevatron Run II

abstract:
  The prospects for discovering and studying signals of low-scale supersymmetry
breaking models at the Tevatron Run II and beyond are explored. These models
include gauge-mediated supersymmetry breaking as the most compelling and
concrete realization, but more generally are distinguished by the presence of a
nearly massless Goldstino as the lightest supersymmetric particle. The
next-lightest supersymmetric particle(s) (NLSP) decays to its partner and the
Goldstino. Depending on the supersymmetry breaking scale, these decays can
occur promptly or on a scale comparable to or larger than the size of a
detector. A systematic analysis based on a classification in terms of the
identity of the NLSP and its decay length is presented. The various scenarios
are discussed in terms of signatures and possible event selection criteria. The
Run II and beyond discovery and exclusion reaches, including the effects of
background, are detailed for the most compelling cases. In addition to standard
event selection criteria based on missing energy and photons, leptons, jets,
taus, tagged b-jets, or reconstructed Z-bosons, more exotic signals of
metastable NLSPs such as displaced photons, large negative impact parameter
tracks, kink tracks, both opposite and same-sign highly ionizing tracks, time
of flight measurements, charge-changing tracks, charge-exchange tracks, and
same-sign di-top events are investigated. The interesting possibility of
observing a Higgs boson signal in events that are efficiently "tagged" by the
unique signatures of low-scale supersymmetry breaking is also considered.


title: The rare decay b--> s gluon beyond leading logarithms

abstract:
  We calculate the alpha_s virtual corrections to the decay width for b --> s
gluon in the standard model. Also the corresponding order alpha_s
bremsstrahlung corrections are systematically calculated in this paper. The
combined result is free of infrared and collinear singularities, in accordance
with the KLN theorem. Taking into account the existing next-to-leading
logarithmic (NLL) result for the Wilson coefficient C_8^(eff), a complete NLL
result for the branching ratio B(b -> s gluon) is derived. Numerically, we
obtain B^(NLL)=(5.0 +/- 1.0) * 10^{-3}, which is more than a factor of two
larger than the leading logarithmic result B^(LL)=(2.2 +/- 0.8) * 10^{-3}.


title: Applications of QCD Factorization in Hadronic B Decays

abstract:
  We review recent advances in the theory of strong-interaction effects and
final-state interactions in hadronic weak decays of heavy mesons. In the
heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can
be calculated from first principles and expressed in terms of semileptonic form
factors and light-cone distribution amplitudes. We summarize the main features
of this novel QCD factorization and discuss its phenomenological applications
to B -> D^(*) L decays (with L a light meson), and to the rare charmless decays
B -> pi K and B -> pi pi.


title:
CP violating supersymmetric contributions to the electroweak $\rho$
  parameter

abstract:
  Effects of CP violation on the supersymmetric electroweak correction to the
$\rho$ parameter are investigated. To avoid the EDM constraints, we require
that arg$(\mu)<10^{-2}$ and the non-universal trilinear couplings
$A_f=(0,0,A_0)$ and also assume that gluinos are heavier than 400 GeV. The CP
phase $\phi_t=$ arg($A_0$) leads to large enhancement of the relative mass
splittings between $\tilde{t}_2$ and $\tilde{b}_L(\tilde{t}_1)$, which in turn
reduces the one-loop contribution of the stop and sbottom to $\Delta \rho$. For
small $\tan \beta$, such a CP violating effect is prominent. We also study how
much the two-loop gluon and gluino contributions are affected by the CP phase.
Possible contributions to the $\rho$ parameter arising from the Higgs sector
with CP violation are discussed.


title: Photons from Pb-Pb Collisions at CERN SPS

abstract:
  High energy photon emission rate from matter created in Pb + Pb collisions at
CERN SPS energies is evaluated. The evolution of matter from the initial state
up to freeze-out has been treated within the framework of (3+1) dimensional
hydrodynamic expansion. We observe that the photon spectra measured by the WA98
experiment are well reproduced with hard QCD photons and photons from a thermal
source with initial temperature ~ 200 MeV. The effects of the spectral changes
of hadrons with temperature on the photon emission rate and on the equation of
state are studied. Photon yield for Au + Au collisions at RHIC energies is also
estimated.


title: Lepton-Flavour-Violation in SUSY Models with and without R-parity

abstract:
  We discuss Lepton-Flavour-Violating phenomena such as $\mu \to e \gamma$,
$\mu \to eee$, and $\mu \to e$ conversion in nuclei in SUSY models with and
without R-parity. We stress that experimental searches for all the LFV
processes are important to distinguish between the different models.


title:
In-medium pi-pi Correlation Induced by Partial Restoration of Chiral
  Symmetry

abstract:
  We show that both the linear and the non-linear chiral models give an
enhancement of the pi-pi cross section near the 2pi threshold in the
scalar-iso-scalar (I=J=0) channel in nuclear matter. The reduction of the
chiral condensate, i.e., the partial chiral restoration in nuclear matter, is
responsible for the enhancement in both cases. We extract an effective
4pi-nucleon vertex which is responsible for the enhancement but has not been
considered in the non-liear models for in-medium pi-pi interaction. Relation of
this vertex and a next-to-leading order terms in the heavy-baryon chiral
lagrangian, L_piN^(2), is also discussed.


title:
The see-saw mechanism and heavy Majorana neutrino masses in an SO(10)
  model

abstract:
  We apply the see-saw mechanism and an SO(10) model to neutrino masses and
mixing in order to estimate the heavy Majorana masses. We discuss shortly the
decay modes of heavy Majorana neutrinos and calculate their contribution to the
lepton number violating processes \mu\to e\gamma, \tau\to\mu\gamma and \tau\to
e\gamma.


title:
A new determination of the QED coupling alpha(M_Z^2) lets the Higgs off
  the hook

abstract:
  We use the available data on e+ e- -> hadrons to determine the value of the
QED coupling at the Z pole. The inclusion of recent preliminary BES-II data in
the analysis is found to reduce the ambiguity in the determination of the
coupling, particularly that arising from the use of either exclusive or
inclusive data in the energy region \sqrt{s} < 2 GeV, in favour of a larger
value of \alpha(M_Z^2)^{-1} = 128.978 +/- 0.027. As a consequence the predicted
value of the mass of the (Standard Model) Higgs boson is increased, so that the
preferred value is just above the LEP2 bound.


title: Pathways to Rare Baryonic B Decays

abstract:
  We point out new ways to search for charmless baryonic B decays: baryon pair
production in association with $\eta^\prime$ is very likely as large as or even
a bit larger than two body $K\pi/\pi\pi$ modes. We extend our argument, in
weaker form, to $B\to \gamma + X_s$ and $\ell\nu +X$. Although calculations are
not reliable, estimates give branching ratios of order $10^{-5}$--$10^{-6}$,
where confidence is gained from recent experimental finding that $B \to D^{*} p
\bar n$, $D^{*} p \bar p \pi$ are not far below $D^*\pi$ and $D^*\rho$ rates.
Observation of charmless baryon modes would help clarify the dynamics of weak
decays to baryonic final states, while the self-analyzing prowess of the
$\Lambda$-baryon can be helpful in CP- and T-violation studies.


title: Effective Majorana neutrino masses

abstract:
  A generalisation of the neutrinoless double beta decay process is presented.
Neutrinoless double beta decay measures only one out of nine possible effective
Majorana neutrino masses in case of three flavours. Limits obtained for all the
matrix elements - some of them for the first time - are presented using data
from $\mu - e$ conversion, neutrino-nucleon scattering, HERA and rare kaon
decays. An outlook towards future possibilities to improve on the bounds is
given.


title:
Sfermion Pair Production in Polarized and Unpolarized $\gamma\gamma$
  Collisions

abstract:
  We calculate total and differential cross sections for the production of
sfermion pairs in photon-photon collisions, including contributions from
resolved photons and arbitrary photon polarization. Sfermion production in
photon collisions depends only on the sfermion mass and charge. It is thus
independent of the details of the SUSY breaking mechanism, but highly sensitive
to the sfermion charge. We compare the total cross sections for bremsstrahlung,
beamstrahlung, and laser backscattering photons to those in $e^+e^-$
annihilation. We find that the total cross section at a polarized photon
collider is larger than the $e^+e^-$ annihilation cross section up to the
kinematic limit of the photon collider.


title: Sfermion production at photon colliders

abstract:
  We calculate total and differential cross sections for sfermion production in
$e^+e^-$ annihilation and in photon-photon collisions with arbitrary photon
polarization. The total cross section at a polarized photon collider is shown
to be larger than the $e^+e^-$ annihilation cross section up to the kinematic
limit of the photon collider.


title: Thermal Dileptons from Quark and Hadron Phases of an Expanding Fireball

abstract:
  A fireball model with time evolution based on transport calculations is used
to examine the dilepton emission rate of an ultra-relativistic heavy-ion
collision. We assume a transition from hadronic matter to a quark-gluon plasma
at a critical temperature T_C between 130-170 MeV. We include thermal
corrections to the hadronic spectra below T_C and use perturbation theory above
T_C. The sensitivity of the spectra with respect to the freeze-out temperature,
the initial fireball temperature and the critical temperature is investigated.


title: B->rho pi decays, resonant and nonresonant contributions

abstract:
  We point out that a new contribution to B decays to three pions is relevant
in explaining recent data from the CLEO and BABAR collaborations, in particular
the results on quasi-two-body decays via a rho meson. We also discuss the
relevance of these contribution to the measurement of CP violations.


title:
Lepton Flavour Violation In Supersymmetric Models with Trilinear
  R-parity Violation

abstract:
  Supersymmetry with R-parity violation (RPV) provides an interesting framework
for naturally accommodating small neutrino masses. Within this framework, we
discuss the lepton-flavour violating (LFV) processes mu -> e gamma, mu -> eee,
and mu -> e conversion in nuclei. We make a detailed study of the observables
related to LFV in different RPV models, and compare them to the expectations of
R-conserving supersymmetry with heavy right-handed neutrinos. We show that the
predictions are vastly different and uniquely characterise each model, thus
providing a powerful framework for experimentally distinguishing between
different theories of LFV. Besides the obvious possibility of amplified
tree-level generation of mu -> eee and mu -> e conversion in nuclei, we find
that even in the case where these processes arise at the one-loop level, their
rates are comparable to that of mu -> e gamma, in clear contrast to the
predictions of R-conserving models. We conclude that in order to distinguish
between the different models, such a combined study of all the LFV processes is
necessary, and that measuring P-odd asymmetries in polarised mu -> eee can play
a decisive role. We also comment on the intriguing possibility of RPV models
yielding a large T-odd asymmetry in the decay of polarised mu -> eee.


title:
Particle Densities in Heavy Ion Collisions at High Energy and the Dual
  String Model

abstract:
  We analyse recent results on charged particle pseudo-rapidity densities from
RHIC in the framework of the Dual String Model, in particular when including
string fusion. The model, in a simple way, agrees with all the existing data
and is consistent with the presence of the percolation transition to the
Quark-Gluon Plasma already at the CERN-SPS.


title: Post-inflationary brane cosmology

abstract:
  The brane cosmology has invoked new challenges to the usual Big Bang
cosmology. In this paper we present a brief account on thermal history of the
post-inflationary brane cosmology. We have realized that it is not obvious that
the post-inflationary brane cosmology would always deviate from the standard
Big Bang cosmology. However, if it deviates some stringent conditions on the
brane tension are to be satisfied. In this regard we study various implications
on gravitino production and its abundance. We discuss Affleck-Dine mechanism
for baryogenesis and make some comments on moduli and dilaton problems in this
context.


title: Flow equations for quark-gluon interactions in light-front QCD

abstract:
  The flow-equation method of continuous unitary transformations is used to
eliminate the minimal quark-gluon interaction in the light-front quantized QCD
Hamiltonian. The coupled differential equations in the two lowest Fock sectors
correspond to the renormalization of the light-front gluon mass and the
generation of an effective quark-antiquark (as well as gluon-gluon)
interaction. The original gauge field coupling is completely eliminated, even
in the presence of degenerate states connected by this interaction. Further, a
more singular $1/q^4$ behavior for the quark and gluon effective interactions
at small gluon momenta is obtained, due to the asymptotic behavior of the
effective gluon mass for small cutoff. We discuss the consequences of this
asymptotic behavior and possible confinement implications.


title: Flavor Asymmetry of the Nucleon Sea

abstract:
  Recent deep inelastic scattering and Drell-Yan experiments have revealed a
surprisingly large asymmetry between the up and down sea quark distributions in
the nucleon. The current status of the flavor asymmetry of the nucleon sea is
reviewed. Implications of various theoretical models and possible future
measurements are also discussed.


title:
Improved Methods for Observing CP Violation in B+/- --> K+/- D0 and
  Measuring the CKM Phase gamma

abstract:
  Various methods are discussed for obtaining the CKM angle gamma through the
interference of the charged B-meson decay channels B- -> K- D0 and B- -> K-
D0-bar where the D0 and D0-bar decay to common final states. It is found that
choosing final states which are not CP eigenstates can lead to large direct CP
violation which can give significant bounds on gamma without any theoretical
assumptions. If two or more modes are studied, gamma may be extracted with a
precision on the order of +/-15 degrees given about 10^8 B-mesons. We also
discuss the case of three body decays of the D0 where additional information
may be obtained from the distribution of the D0 decay products and consider the
impact of D-D-bar oscillations.


title: NRQCD Analysis of Bottomonium Production at the Tevatron

abstract:
  Recent data from the CDF collaboration on the production of spin-triplet
bottomonium states at the Tevatron p \bar p collider are analyzed within the
NRQCD factorization formalism. The color-singlet matrix elements are determined
from electromagnetic decays and from potential models. The color-octet matrix
elements are determined by fitting the CDF data on the cross sections for
Upsilon(1S), Upsilon(2S), and Upsilon(3S) at large p_T and the fractions of
Upsilon(1S) coming from chi_b(1P) and chi_b(2P). We use the resulting matrix
elements to predict the cross sections at the Tevatron for the spin-singlet
states eta_b(nS) and h_b(nP). We argue that eta_b(1S) should be observable in
Run II through the decay eta_b -> J/psi + J/psi.


title: $b \to s \ell^+ \ell^-$ decays in and beyond the Standard Model

abstract:
  We briefly review the status of rare radiative and semileptonic $b \to s
(\gamma, \ell^+ \ell^-)$, ($\ell=e,\mu$) decays. We discuss possible signatures
of new physics in these modes and emphazise the role of the exclusive channels.
In particular, measurements of the Forward-Backward asymmetry in $B \to K^*
\ell^+ \ell^-$ decays and its zero provide a clean test of the Standard Model,
complementary to studies in $b \to s \gamma$ decays. Further, the
Forward-Backward CP asymmetry in $B \to K^* \ell^+ \ell^-$ decays is sensitive
to possible non-standard sources of CP violation mediated by flavor changing
neutral current $Z$-penguins.


title:
Maximal $\nu_\mu - \nu_\tau$ oscillations, the see-saw mechanism and the
  Exact Parity Model

abstract:
  We examine one simple mechanism which leads to approximate maximal $\nu_\mu -
\nu_\tau$ oscillations in the standard see-saw model. In particular, we show
that this scheme could be implemented in the Exact Parity Model (also known as
the mirror matter model). Within this framework the solar neutrino problem is
solved by maximal $\nu_e \to \nu'_e$ oscillations (with $\nu'_e$ is the
essentially sterile mirror partner of $\nu_e$) and the LSND evidence for $\nu_e
\to \nu_\mu$ oscillations can also be explained.


title: Two Loop QCD Vertices and Three Loop MOM $\beta$ functions

abstract:
  We present numerical results for the two loop QCD corrections to the ghost
gluon vertex, the quark gluon vertex, and the triple gluon vertex in the
massless limit at the symmetric point. We restrict ourselves to the tensor
structures existing in the tree level. The corrections are used to examine
different coupling constant definitions in momentum subtraction schemes and the
corresponding three-loop $\beta$ functions.


title: Solar Neutrino Solutions in Non-Abelian Flavor Symmetry

abstract:
  We have studied the large mixing angle MSW solution for the solar neutrinos
in the non-abelian flavor symmetry. We predict the MNS mixing matrix taking
account of the symmetry breakings.


title: The structure of the light scalar mesons and QCD sum rules

abstract:
  The structure of the light scalar mesons is elucidated by the investigation
of the S-matrix poles and the q-qbar spectral density in a coupled channel
model that includes pi-pi, K-Kbar and q-qbar channels. It is shown that the
dynamical origin of the sigma and f0(980) mesons is consistent with the
observed spectrum of the scalar states. The K-Kbar molecular picture of the
f0(980) is in good agreement with recent experimental data on the decay phi -
gamma pi pi from Novosibirsk.


title:
Leptoquark Pair Production in \gamma\gamma Scattering: Threshold
  Resummation

abstract:
  The possibilities to pair-produce leptoquarks in photon-photon collisions are
discussed. QCD threshold corrections lead to a strong enhancement of the
production cross section. Suitably long-lived leptoquarks ($\Gamma_\Phi \lsim
100 \MeV$) may form Leptoquarkonium states.


title:
Magnetic monopoles and vortices in the standard model of electroweak
  interactions

abstract:
  These lectures start with an elementary introduction to the subject of
magnetic monopoles which should be accesible from any physics background. In
the Weinberg-Salam model of electroweak interactions, magnetic monopoles appear
at the ends of a type of non-topological vortices called electroweak strings.
These will also be discussed, as well as recent simulations of their formation
during a phase transition which indicate that, in the (unphysical) range of
parameters in which the strings are classically stable, they can form with a
density comparable to topological vortices.


title: O(alpha^3 ln alpha) corrections to positronium decay rates

abstract:
  We compute O(alpha^3 ln alpha) corrections to the decay rates of para- and
orthopositronium into two and three photons, respectively. For this calculation
we employ the nonrelativistic QED regularized dimensionally and we explain how
in this framework the logarithms of the fine structure constant can be
extracted.


title: Correlating the Higgs and Kaon Sector CP Violations

abstract:
  Taking the most general two-doublet models with explicit CP violation in the
Higgs sector but no phase in the CKM matrix, we determine the correlation
between the Higgs and Kaon sectors using the experimental values of $\Delta
M_K$ and $\epsilon_K$. It is found that: there is a direct correlation between
strength of FCNC couplings and the Higgs masses, and the lightest Higgs is
nearly pure CP-even, but this small CP-odd composition gives large enough
contribution to $\epsilon_K$.


title:
Non-Relativistic Effective Field Theory for Perturbative Heavy
  Quark--Antiquark Systems

abstract:
  Recent developments for an effective theory for non-relativistic perturbative
quark-antiquark systems are reviewed and some applications are discussed.


title: Bottom Quark Mass from Upsilon Mesons: Charm Mass Effects

abstract:
  The effects of the finite charm quark mass on bottom quark mass
determinations from $\Upsilon$ sum rules are examined in detail. The charm
quark mass effects are calculated at next-to-next-to-leading order in the
non-relativistic power counting for the $\Upsilon$ sum rules and at order
$\alpha_s^3$ for the determination of the bottom MSbar mass. For the bottom 1S
mass, which is extracted from the $\Upsilon$ sum rules directly, we obtain
$M_b^{1S}=4.69\pm 0.03$ GeV with negligible correlation to the value of the
strong coupling. For the bottom MSbar mass we obtain $\bar M_b(\bar M_b) =
4.17\pm 0.05$ GeV taking $\alpha_s^{(n_l=5)}(M_Z)=0.118\pm 0.003$ as an input.
Compared with an analysis where all quarks lighter than the bottom are treated
as massless, we find that the finite charm mass shifts the bottom 1S mass,
$M_b^{1S}$, by about -20 MeV and the MSbar mass, $\bar M_b(\bar M_b)$, by -30
to -35 MeV.


title: Radion Mediated Supersymmetry Breaking

abstract:
  We point out that in supersymmetric theories with extra dimensions, radius
stabilization can give rise to a VEV for the $F$ component of the radius
modulus. This gives an important contribution to supersymmetry breaking of
fields that propagate in the bulk. A particularly attractive class of models is
obtained if the standard-model gauge fields propagate in the bulk, while the
quark and lepton fields are localized on a brane. This leads to gaugino
mediated supersymmetry breaking without the need for singlets in the hidden
sector. We analyze a simple explicit model in which this idea is realized.


title: Modified Wandzura-Wilczek Relation with the Nachtmann Variable

abstract:
  If one retains M^2/Q^2 terms in the kinematics, the Nachtmann variable \xi
seems to be more appropriate to describe deep inelastic lepton-nucleon
scattering. Up to the first power of M^2/Q^2, a modified Wandzura-Wilczek
relation with respect to \xi was derived. Kinematical correction factors are
given as functions of \xi and Q^2. A comparison of the modified g_2^WW(\xi) and
original g_2^WW(x) with the most recent g_2 data is shown.


title:
The Early Mirror Universe: Inflation, Baryogenesis, Nucleosynthesis and
  Dark Matter

abstract:
  There can exist a parallel `mirror' world which has the same particle physics
as the observable world and couples the latter only gravitationally. The
nucleosynthesis bounds demand that the mirror sector should have a smaller
temperature than the ordinary one. By this reason its evolution should be
substantially deviated from the standard cosmology as far as the crucial epochs
like baryogenesis, nucleosynthesis etc. are concerned. Starting from an
inflationary scenario which could explain the different initial temperatures of
the two sectors, we study the time history of the early mirror universe. In
particular, we show that in the context of the GUT or electroweak baryogenesis
scenarios, the baryon asymmetry in the mirror world should be larger than in
the observable one and in fact the mirror baryons could provide the dominant
dark matter component of the universe. In addition, analyzing the
nucleosynthesis epoch, we show that the mirror helium abundance should be much
larger than that of ordinary helium. The implications of the mirror baryons
representing a kind of self-interacting dark matter for the large scale
structure formation, the CMB anysotropy, the galactic halo structures,
microlensing, etc. are briefly discussed.


title: Why Use a Hamilton Approach in QCD?

abstract:
  We discuss $QCD$ in the Hamiltonian frame work. We treat finite density $QCD$
in the strong coupling regime. We present a parton-model inspired
regularisation scheme to treat the spectrum ($\theta$-angles) and distribution
functions in $QED_{1+1}$. We suggest a Monte Carlo method to construct
low-dimensionasl effective Hamiltonians. Finally, we discuss improvement in
Hamiltonian $QCD$.


title:
b --> s \tau^+ \tau^- decay in the two Higgs doublet model with flavor
  changing neutral currents

abstract:
  We study the decay width and forward-backward asymmetry of the lepton pair
for the inclusive decay b --> s \tau^+ \tau^- in the two Higgs doublet model
with three level flavor changing neutral currents (model III) and analyse the
dependencies of these quantities on the model III parameters, including the
leading order QCD corrections. We found that there is a considerable
enhancement in the decay width and neutral Higgs effects are detectable for
large values of the parameter \bar{\xi}_{N,\tau\tau}^D.


title:
Soft Gluon Resummation for Polarized Deep-inelastic Production of Heavy
  Quarks

abstract:
  We present the threshold resummation for the cross section of heavy quark
production in polarized deep-inelastic scattering to next-to-leading
logarithmic accuracy and in single-particle inclusive kinematics. We expand our
resummed result in alpha_s to next-to-leading and next-to-next-to-leading order
and study the impact of these higher order corrections on the charm structure
function g_1 in the kinematical range accessible to the HERMES and COMPASS
experiments.


title:
Coherence Effects in Diffractive Electroproduction of rho Mesons from
  Nuclei

abstract:
  A systematic multiple scattering formalism for vector meson electroproduction
from nuclei is developed, with emphasis on the formation, propagation and
hadronization scales for quark-gluon fluctuations of the virtual high-energy
photon. The theory is compared to HERMES measurements of rho electroproduction
on 14N. The nuclear transparency as a function of the vector meson propagation
length is well reproduced.


title: Natural Mass Generation for the Sterile Neutrino

abstract:
  We point out that there is a serious cosmological problem in the
supersymmetric standard model if a sterile neutrino is responsible for the
solar neutrino oscillation, and propose a possible solution to this problem. We
show that our solution induces naturally a mass of order 10^{-4} eV for the
sterile neutrino, which is deeply related to the mechanism of supersymmetry
breaking.


title: Topological and confining properties of Abelian-projected SU(3)-QCD

abstract:
  In this talk, we discuss several topics related to the Abelian-projected
SU(3)-QCD. First of them is the Aharonov-Bohm effect emerging during the
extension of this theory by the introduction of the $\Theta$-term. Another
topic is devoted to various consequences of screening of the dual vector bosons
by electric vortex loops. In particular, it is demonstrated that this effect
modifies significantly the interaction of quarks. Next, the influence of
screening to electric and magnetic field correlators in the four-dimensional
Abelian-projected SU(3)-QCD is studied. Finally, the bilocal correlator of
electric field strengths in the three-dimensional gas of SU(3)
Abelian-projected monopoles is discussed.


title:
Distinct Hagedorn temperatures from particle spectra: a higher one for
  mesons, a lower one for baryons

abstract:
  We analyze experimental particle spectra and show that the Hagedorn
temperature is significantly larger for mesons than for baryons. The effect can
be explained within dual string models: excitations of three strings in the
baryon produce ``faster'' combinatorics than a single string in the meson,
hence lead to a more rapid growth of baryons than mesons. Predictions of other
approaches for the gross features of particle spectra are also discussed.


title: Primordial black hole production due to preheating

abstract:
  During the preheating process at the end of inflation the amplification of
field fluctuations can lead to the amplification of curvature perturbations. If
the curvature perturbations on small scales are sufficiently large, primordial
black holes (PBHs) will be overproduced. In this paper we study PBH production
in the two-field preheating model with quadratic inflaton potential. We show
that for many values of the inflaton mass m, and coupling g, small scale
perturbations will be amplified sufficiently, before backreaction can shut off
preheating, so that PBHs will be overproduced during the subsequent radiation
dominated era.


title: On the charge radius of the neutrino

abstract:
  Using the pinch technique we construct at one-loop order a neutrino charge
radius, which is finite, depends neither on the gauge-fixing parameter nor on
the gauge-fixing scheme employed, and is process-independent. This definition
stems solely from an effective proper photon-neutrino one-loop vertex, with no
reference to box or self-energy contributions. The role of the $WW$ box in this
construction is critically examined. In particular it is shown that the
exclusion of the effective WW box from the definition of the neutrino charge
radius is not a matter of convention but is in fact dynamically realized when
the target-fermions are right-handedly polarized. In this way we obtain a
unique decomposition of effective self-energies, vertices, and boxes, which
separately respect electroweak gauge invariance. We elaborate on the tree-level
origin of the mechanism which enforces at one-loop level massive cancellations
among the longitudinal momenta appearing in the Feynman diagrams, and in
particular those associated with the non-abelian character of the theory.
Various issues related to the known connection between the pinch technique and
the Background Field Method are further clarified. Explicit closed expressions
for the neutrino charge radius are reported.


title: A full one-loop charge symmetry breaking effective potential

abstract:
  We calculate the one-loop contributions to the effective potential for the
minimal supersymmetric model when scalar fields other than the Higgses have
vacuum expectation values. The importance of these contributions for studies of
charge and colour breaking bounds is discussed.


title: Couplings of a Light Dilaton and Violations of the Equivalence Principle

abstract:
  Experimental discovery of the dilaton would provide strong evidence for
string theory. A light dilaton could show up in current tests of the inverse
square law for gravity at sub-millimeter distances. In the large extra
dimension scenario, Kaluza-Klein excitations of the dilaton can also contribute
to the cooling of supernovae. In order to quantify these effects we compute the
couplings of a low energy dilaton to matter. These predominantly arise from the
fundamental dilaton coupling to the gluon field strength, which receives a
sizable enhancement from QCD scaling. We show that detection of the dilaton
will give a direct measurement of the QCD coupling constant at the string
scale. Particular attention is paid to the size of equivalence principle
violating dilaton couplings.


title:
Radiative Corrections to Chargino Production in Electron-Positron
  Collisions with Polarised Beams

abstract:
  We study radiative corrections to chargino production at linear colliders
with polarised electron beams. We calculate the one-loop corrected
cross-sections for polarised electon beams due to three families of quarks and
squarks, working in the $\bar{MS}$ scheme, extending our previous calculation
of the unpolarised cross-section with one-loop corrections due to the third
family of quarks and squarks. In some cases we find rather large corrections to
the tree-level cross-sections. For example for the case of right-handed
polarised electrons and large $\tan \beta$ the corrections can be of order 30%,
allowing sensitivity to the squark mass parameters.


title: Chiral Symmetry and the Nucleon Nucleon Interaction

abstract:
  Various aspects of the application of Effective Field Theory (EFT) to the
Nucleon-Nucleon (NN) interaction are considered. We look for contributions
beyond One Pion Exchange which are predicted by Chiral Symmetry.
  Using the formalism of the Wilson Renormalisation Group (RG) we review power
counting in a simplified EFT containing only nucleons. For weak scattering at
low energy, we find a natural expansion of the scattering matrix around the
unique trivial fixed point of the RG. For strong scattering at low energy, the
calculation can be organised in a useful and systematic way by expanding the
potential around a non-trivial fixed point corresponding to a bound state of
two nucleons at threshold. The resulting expansion of the inverse of the
scattering matrix reproduces the effective range expansion order by order.
  The extension of this EFT to include pions in a manner consistent with chiral
symmetry is discussed. By considering a modified effective range expansion, we
find that the small momentum expansion in S-wave scattering converges slowly,
if at all. The NN potential is written down to third order in small momenta.
With a cut-off in coordinate space, we calculate phase shifts in peripheral
partial waves for which the EFT predictions are parameter-free, and for which
we may use the expansion around the trivial fixed point. We find several
partial waves in which the effects of two-pion exchange can be isolated, but no
strong evidence is found for the convergence of the small momentum expansion at
this order.


title:
Bremsstrahlung from a Microscopic Model of Relativistic Heavy Ion
  Collisions

abstract:
  We compute bremsstrahlung arising from the acceleration of individual charged
baryons and mesons during the time evolution of high-energy Au+Au collisions at
the Relativistic Heavy Ion Collider using a microscopic transport model. We
elucidate the connection between bremsstrahlung and charge stopping by
colliding artificial pure proton on pure neutron nuclei. From the intensity of
low energy bremsstrahlung, the time scale and the degree of stopping could be
accurately extracted without measuring any hadronic observables.


title: Fermion Mass Hierarchies and Small Mixing Angles from Extra Dimensions

abstract:
  In this paper we study renormalization-group evolutions of Yukawa matrices
enhanced by Kaluza-Klein excited modes and analyze their infrared fixed-point
structure. We derive necessary conditions to obtain hierarchies between
generations on the fixed point. These conditions restrict how the fields in the
models can extend to higher dimension. Several specific mechanisms to realize
the conditions are presented. We also take account of generation mixing effects
and find a scenario where the mixing angles become small at low energy even
with large initial values at high-energy scale. A toy model is shown to lead
realistic quark mass matrices.


title: Ultra-high energy cosmic neutrinos

abstract:
  Several cosmologically distant astrophysical sources may produce ultra-high
energy cosmic neutrinos (E > 10^6 GeV) of all flavors above the atmospheric
neutrino background. I study the effects of vacuum neutrino flavor mixing on
this cosmic neutrino flux. Prospects for observations of these ultra-high
energy cosmic neutrinos in large underwater/ice neutrino telescopes are also
briefly discussed.


title: Twin Peaks

abstract:
  The on-shell imaginary part of the retarded selfenergy of massive $\vr^4$
theory in 1+1 dimensions is logarithmically infrared divergent. This leads to a
zero in the spectral function, separating its usual bump into two. The twin
peaks interfere in time-dependent correlation functions, which causes
oscillating modulations on top of exponential-like decay, while the usual
formulas for the decay rate fail. We see similar modulations in our numerical
results for a mean field correlator, using a Hartree ensemble approximation.


title: Effective Field Theory of the Pion-Nucleon-Interaction

abstract:
  In the first part of the talk, I discussed the nature of the effective theory
that describes the properties of the pion-nucleon-interaction at low energies,
using the static model as a starting point. In the second part, I then pointed
out that the infrared singularities occurring in the pi-N scattering amplitude
are stronger and of a more complex structure than those encountered in pi-pi
scattering. A formulation of the effective theory that properly accounts for
these was described and the results obtained thereby were illustrated with a
few examples.


title: Chiral Dynamics

abstract:
  The effective field theory relevant for the analysis of QCD at low energies
is reviewed. The foundations of the method are discussed in some detail and a
few illustrative examples are described.