Fundamental interaction and the strong interaction. Their magnitude and behaviour vary greatly, as described in the table below. Modern physics attempts to explain every observed physical phenomenon by these fundamental interactions. Moreover, reducing the number of different interaction types is seen as desirable. Two cases in point are the unification of: Both magnitude ("relative strength") and "range", as given in the table, are meaningful only within a rather complex theoretical framework. It should also be noted that the table below lists properties of a conceptual scheme that is still the subject of ongoing research. The modern (perturbative) quantum mechanical view of the
Letters in Mathematical Physics abstract or index "Letters in Mathematical Physics": Academic OneFile, Academic Search, Astrophysics Data System, Chemical Abstracts Service, Current Contents/Physical, Chemical and Earth Sciences, Current Index to Statistics, EBSCO, EI-Compendex, INIS Atomindex, Inspec, Mathematical Reviews, ProQuest, Science Citation Index, Scopus, Summon by Serial Solutions, and Zentralblatt MATH. According to the Journal Citation Reports, its 2011 impact factor is 1.819 and 2012 impact factor is 2.415. Letters in Mathematical Physics Letters in Mathematical Physics is a peer-reviewed scientific journal in mathematical physics published by Springer Science+Business Media. It publishes letters and longer research articles, occasionally also articles containing topical reviews. It is