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Considering the probabilistic relationship between the momentum and position of an electron, are the pictures that show the interaction between electrons and positrons an accurate description of particle motion? We often see visuals that represent the probabilistic nature of particles as probability clouds. How can this converge to well-defined paths? (I never studied this subject, this is just knowledge from general physics books and videos.) | 0 |
By this I mean say you had and entire galaxy to work with, and you could measure the exact wavelengths of the waves you send out and record it. You would shoot this light beam across the galaxy and measure the exact wavelength of the light you are transmitting, and receiving. Could you compare the difference in the wavelengths between the same light and calculate the one way speed of light from it? | 0 |
Since value of electric field decreases as we go from surface to the centre for a solid insulating uniformly charged sphere then why does the potential increases as we go from surface to the centre?According to me we will need to do less work against weak electric field therefore the potential will be less as we go inside the sphere from the surface since electric field is decreasing as we go from the surface to the centre. | 0 |
i think the title speaks for itself, since the defining trait for NP class is that - they are the set of decision problems verifiable in polynomial time by a deterministic Turing machine. thus it shouldn't matter if the algorithm computing the function belongs to any particular class - exp or factorial, even non-PR , as long as they are computable, but i am unable to find any specific example. if there aren't any known such algorithms or problems, can it be proven that they atleast should exist ? | 0 |
Just as underwhelm/overwhelm exist without any usage of 'whelmed' (generally speaking) I'm wondering if there's any adverb ending in -ly without an adjectival counterpart (or that has dropped out of usage). For example where 'he walked XYZly' is recognisable, correct, or common for this or some other time period; whilst 'his walk was XYZ' is not. NB: I've found no other answers for this question elsewhere, and search engines usually lead to explanations of 'flat adverbs' not ending in -ly which is not what I'm asking. | 0 |
I can't make out clearly what could be defined as a "topic element". In "A Communicative Grammar of English", Geoffrey Leech has written: Fronting is often accompanied by inversion; that is, not only the topic element, but the verb phrase, or part of it, is moved before the subject. Accompanied by this diagram: Now, "x" in the above diagram is stated to be "the topic element". However, from what I've learned, the topic is usually either "given info" or used to link statements. Moreover, they are usually subjects. Yet here "down" and "never" are considered to be "the topic element"? I'm truly desperate for an answer here. | 0 |
Reflective is obvious, but what about the other properties? It's weird when we check the symmetric property of the identity relation. The symmetric property happens when (in a matrix representation) the upper triangle and the lower triangle that exists in a matrix that's divided by the matrix's diagonal get mirrored. Also, you can make a graph representation of the relation and see that it's just loops. So is it symmetric or not? (also, check out if it's antisymmetric or not because I think the matrix representation shows that it's antisymmetric) | 0 |
"Underpinned by left-wing perspective,the defence gains in significance,based as it is on the development of critical art of inheritance,of combing past and present and establishing links to shape a better world." In this sentence how the word "based" is used as i have read based on but here is nothing such.please reply correct should have been "Underpinned by a progressive left-wing perspective, the defense gains in significance, as it is based on the development of critical art of inheritance, combing past and present and establishing links to shape a better world.". so how it is used? | 0 |
How rare or how common are the analytic (differentiable infinitly many times) functions in real applied math? Is it like a "this almost never happens" or is it "most of the time you can approximate a physics experiment with analitic functions (and if you failed, you are bad at math)"? I ask because there are so many nice properties of analytic functions in complex analysis. But are they relevant? Seems like "differentiable forever" is too strong of a limitation. | 0 |
So - I know that when we observe galaxies, we are observing their past. And that if the same past-them were to be looking at us, they would see our past. But when we look at their past - that is a moment in time that would, to them, be the present. So, what I cannot find an answer to (possibly because I don't know how best to search for it) is: does it then make sense to say that it is possible that a galaxy that is future to us, could be observing our present - but as past to them? (if that is so then that opens up a whole can of worms that all time is occurring at all times, yes?) | 0 |
Hypothetically speaking if you had a satellite going near the speed of light in a straight line towards an exoplanet light years away and that satellite had a telescope pointed at the surface of an exoplanet. What could a year long journey look like, while traveling near the speed of light, through the lens of that telescope that what light years away pointed directly at the surface of the exoplanet? would the telescope capture the planet in fast forward as the light information would be entering the telescope faster? Would it be slower as time dilates for exoplanet because it not moving the sleed of light? | 0 |
I have to prove that if the dimension of vector spaces V and W is the same then T: V->W is injective if it is surjective. My idea is as such: know that all elements in W have corresponding element in V (surjective) Know that all elements in V correspond to some element in W (map) I want to use that I know that V and W must be over the same field (by homogeneity) and generalize that since the dimension is the same then the number of elements must be the same, thus proving injection. Is this valid? | 0 |
one day I kept my phone in my pant pocket, I haven't opened it for a long time. My phone is covered with a plastic case. So why the phone is getting wet when I observed it after some time even though plastics are non conductive towards heat. When I kept my phone in pant pocket without the case then no wet has been observed by me on the phone Whether it is due to heat of the phone or the sweat of mine due to the heat released by the phone or the heat is mainly due to heat from the screen of the phone (as some background apps were running at the time) which is open and it is not close by any non-conductive material | 0 |
The normal force may be unevenly distributed on the surface of contact between two bodies. I had a discussion with my friend but was unable to prove whether this assertion is true or false under two RIGID bodies. I know it is a unreal question. Therefore, I am seeking a mathematical solution to this question. (If this question is independent from classical mechanics, how to prove?) | 0 |
In India, most educated People say that " my exams have been preponed" As an English teacher I know that Americans say moved up and Britishers say that advanced in the context. One of the best English professors I know in India says that prepone is the right word in the context.Even some native speakers said that the word prepone could be accepted. I would like to know the opinion of the experts in the group. | 0 |
When we work with rational numbers, our continued fraction will have a finite number of elements. Are there ways to estimate the number of elements of a continued fraction when expanding a rational number? For example, in the following form: "For the chosen rational number N, continued fraction will contain at least/at most/strictly M elements" The obvious way is to implement the continued fraction decomposition algorithm and simply count the number of elements each time the loop passes. But this method can be quite time-consuming if there are a large number of elements of the continued fraction. I tried to find the answer and the only thing I found was this thread: Nth number of continued fraction But it ultimately came down to what I said above. | 0 |
Like how Taylor Swift fans say that she needs to take private jets because fans would make her taking public transport untenable. So it's the fans themselves that are the reason for her behaviour, which they are making excuses for. Is there a term for such people, or for what they are doing? An example of how it could be used: Fans are (creating the exceptional need for an excuse they are making) Taylor Swift's use of private jets' or something like that. | 0 |
I need to write an equation to determine how rotating a digital balls path with the ball as the center of rotation effects the amount it moves on the x&y axis each frame. I made a table of points on the equation to help me write it, but I'm unable to convert the equation into points. I linked an image of the table here. Does anyone know the answer? I think it's a helix. It's fine if you need to switch which axis each column corresponds to in the equation, as long as you mention which ones you switched. Click here to see the table | 0 |
I'm looking for an interesting application of Sequences and Series (theory from mathematical analysis) in the field of Operational Research, in particular involving combinatorics or linear optimization problems. I have tried only chat GPT for now and all I could get is an application of Dynamic programming to solve the knapsack problem where series and sequences are defined for recurrence. I was wondering if there is another one or maybe an interesting application not from the Operation Research fields. Thanks in advance. | 0 |
The definition of exegesis is Bible leaning and thus is not a word many outside of the church are familiar with. And yet people can understand the idea of trying to interpret a text as the author or authors meant it to be understood. This applies to the US Constitution. Is there a familiar word that is used by secular society that means to understand what the authors meant when they wrote a text? | 0 |
Recently, I've been solving problems involving Burnside's Lemma. The question often says: "Find all different colorings if we identify colorings when they transform into each other under some rotation/symmetry/isometry/isomorphism." I get confused about in which cases I need to consider the figure being "turned inside out" like for example tetrahedron can be. It seems to me that: rotation - no symmetry - yes isometry - yes isomorphism - yes Assuming it is possible for a given shape. Is this true? Or it depends? | 0 |
@JonathanZ Thanks for going all the way to help me out. An oil-pipe has to connect the oil-well O and the factory F, between which there is a river whose banks are parallel. The pipe must cross the river perpendicular to the banks. Find the position and nature of the shortest such pipe and justify your answer. I tried out this problem with some numbers and got the idea of path of minimum pipe length. How can I do it more rigorously? This is what I got through my intuition. I think blue one is the minimal path. | 0 |
Example: a close friend died of cancer, so you feel very bad. Yet they were old and no longer suffering, so you also feel glad. Both feelings are strong and truthful, yet the emotions about the same object or situation equally oppose each other. Ambivalent comes close, but I was looking for another word to more exactly describe the situation. Ambivalent would describe a struggle where you might not like something about someone, yet still like other characteristics, hence you are uncertain how to balance the situation (be their friend or walk away). What word describes when you are not struggling to balance two truths, but accept both opposing feelings? I ask because we are helping someone who is grieving. | 0 |
In the literature and comments, I have met two pieces of jargon: Low energy SUSY, High energy SUSY I'm confused about the technical and well-defined conceptual differences between the two type of Supersymmetry? Of course one such difference should be the scale at which SUSY is broken, but I have no idea how high and low are distingushed formally and how they differ fundamentally from each other? For example, I read a comment due to Peter West: that LHC can only rule out low energy SUSY which is different matter from high energy SUSY. | 0 |
I pasted the whole fragment from the book "Teaching Physics by Laurance Viennot". I generally understand this fragment. However, I am not sure if I understand what author means by the phase at each of those points then has to be readjusted in order for a geometrical optical treatment to be applied to that "object". I circled that fragment with blue. Can you give me more guidance how to understand that? | 0 |
So during our numerics course we learned a few interpolation methods Aitken/Neville, divided differences,Lagrange and the Vandermonde matrix. How these work is clear to me for the most part, I'm just wondering what are the advantages and disadvantages of the respective methods compared to each other? I know about a few things here and there like some methods being easier to expand when gaining new points but our script seems a bit sparse on that info and I'd like a more holistic picture. | 0 |
Do two mechanical transverse waves traveling in the same medium have the same speed whatever the source might be? If the answer to this question is yes, can I generalize and say "all waves of the same EXACT category traveling in same medium have the same wave speed" and by the same exact category I meant to specify the exact type of the wave, that is to state its both kinds; mechanical and traverse, or mechanical and longitudinal. That being said, I can't say that two mechanical waves one is transverse while the other is longitudinal have the same speed in the same medium, they could have the same speed though, but its not a general statement, is that right? | 0 |
I was looking At a couple different replies to some questions on here and I kept seeing people saying that larger mass black holes have a lower gravitaional strength on their surface than lower mass black holes. I am no expert by any stretch of the imagination but I would of assumed that the larger the mass the more powerful the gravity. Does anyone know why this is | 0 |
I've been playing with this problem for a long time, but I don't see a solution yet. Consider the sides of a trapezoid of lengths a and b, a > b (not heights) ( see edition (and the bases major "a" and minor "b"). Determine the height of this trapezoid using two different methods. Don't use trigonometry Can you help me EDIT Typing error: a and b sides, a and b are not heights, a>b, the bases greatest "p" and least "q" There is also the image that refers to the data | 0 |
I must learn tons of identities for vector calculus for Electromagnetism, but they were taught as a list of items to memorize. Some of them are reasonable to follow (such as gradient or curl acting on sum or product of vectors), but I'm lost with curl and vector product. I lack any formal math background, so I'd like a book/ page where these expressions are justified/ derived in an understandable way. Thanks in advance! | 0 |
In the photo I added,there is a question as you can see and its given solution. When the switch S was open, charge on each capacitor was calculated and the voltage was taken as the net voltage of the two connected batteries. But for calculating charges on the two capacitors when the switch S is closed, only the voltage of one battery was taken for the corresponding capacitor. Why is it so. Why the effect/voltage of other battery is ignored.Either I am lacking some concept clarity or the charge must have flown through other sides( A and C) as well. What will be the new charge on the two capacitors after closing the switch S if the charge flowing through each section (A,B and C) is considered? | 0 |
As we try to refine our spectrometer better and better each day, like first we observed doublets in Hydrogen atom, then we observed fine structure's in hydrogen like and in many heavy elements. Then we saw hyper fine splitting too where atomic nucleus takes part too. My question is what will happen in the case where we have a spectrometer and we are observing one single line of a particular spectrum which is so sharp that (till my knowledge I know splitting till hyper-fine level) will we observe a single a infinite sharp line or what. Or there will be some error like Doppler broadening etc. kind of situation. | 0 |
I wonder if there is a tex library that can create an equation like this (found in this paper and the authors actually create a figure for this, not in tex) With some research, I see that the arrows can be made using witharrows but I am not sure about the colored part, specifically the I_i(D) part where the two colors (dark green & light green) overlap. Any pointer will be highly appreciated! Thanks! | 0 |
I was looking through some old documents and pitching them from my time at uni. In there, I found some materials handling notes, and one regarding the handling Uranium metal bars. Basically, it said that they didn't require any special handling. As a thought experiment, this makes sense as the bars are just purified ore and thereby very dense and the radiation would be just surface emission. Is this true? | 0 |
I read this sentence earlier, and it struck me as incorrect: A number of parameters is associated with an open connection. My first thought was the is should be an are, but talked myself out of that because number is singular. Then I asked my wife (family grammarian), and she says that the sentence is incorrect; it should read as follows: A number of parameters are associated with an open connection. We checked out some examples using an online dictionary, and it seems she may be correct. What's the answer - which is correct? | 0 |
I was reading a USACO Guide Page on data types and I came across two formulas for the absolute and relative difference in the desired answer and the actual answer that is outputted. This is meant to be calculate the absolute and relative errors but what really is the difference between them? I tried to read this question but could not understand it. From a mathematical standpoint what is this exactly and what are its true applications in programming? Where would I need each type? Here is an image of the text I was reading: Image of text from USACO | 0 |
I am trying to learn contour integration, for the purpose of learning another technique I can apply to computing definite (real) integrals. Although I can apply the process well enough, ( with some issues in contour selection, but that's a different question). The problem i am dealing with, is how can a person tell if a particular real integrand is a good candidate for contour integration? I've read something about "five cases" where it can be used but it felt weird for such an arcane technique to be limited to precisely five situations so I came here to ask instead. | 0 |
In many contexts we have the concept of mapping one element to another. Is the mapping itself an object which has a lifecycle? What makes the mapping come into existence? I may not be asking this very articulately but when it is stated that there is a mapping, what causes this? Where is the information that says the mapping exists stored? Is this related perhaps to Axiom of Choice? | 0 |
I have been trying to solve this question from twitter for like two days could anyone help me with this? All the credits go to the name mentioned in the image My attempt to solve: I think it's harder to understand my messy diagram. But all I have done here is drawing a parallel line from a vertice to the opposite side of the square and with that I have find the lengths of the mentioned segments in terms of x Thank u in advance for looking into this problem | 0 |
First, I know it "worked", in physics sense. My question is what happened in the math sense. When promoting something, such as a field, to an operator, am I essentially mapping the field to (infinitely dimension) operator that depends on spacetime? And the canonical commutator just somehow followed from this map (my guess is that the map somehow preserve the Poisson bracket and somehow map the bracket to commutator.. or maybe we can just get it somehow from operator's dependence on spacetime?)? Alternatively, could it be that I am mapping the field to a more intricate mathematical object that encompasses canonical commutator (as well as other symmetry and their generator? as the operator version of the charge just somehow works quite well as a generator)? | 0 |
I am in the process of writing a research paper that compares my Methods A and B against a commonly accepted gold standard (reference) method. All methods produce objects that are identical in the ideal case. I am now in the search for a noun to refer to the objects which are not the reference objects, i.e. objects produced by A and B, in the context of the comparison. Example sentence: The ______ are smaller compared to the reference objects. So far I have tried working with test objects and input objects and sample, but they appear wrong to my intuition. Ideally it would be a term familiar to other academics. | 0 |
Huygens and Maxwell have wave theories about light. On the other hand Planck and Einstein have theories about particle nature of light and could explain blackbody radiation and photoelectric effect which theories of Huygens and Maxwell unable to explain. What about Newton's particle theory of light? Does it have advantage of explaining a phenomenon that all wave theories unable to explain? Is Newton theory of light could be considered as root for "essential need" for particle imagination of light or it is merely a non-essential theory when we could have wave theories? | 0 |
I'm not a mathematician, but I've read alot about QFT theory. The way it is visualized are different levels of energy and the fields interacting with one another. Am I correct that these fields overlap each other in the same point in space? What if each point in space has exactly the same amount of energy, and in order to create higher levels of energy, that energy has to be drawn from the points around it which would pull and twist space as it absorbs the surrounding energy to produce the known subparticles. Do we consider QFT fields as more energy in a single space? Or do we consider each field as just a description of a higher energy state? | 0 |
So here's something I was wondering about. Let's say I have to have boundary conditions in flrw metric which does not leave the universe isotropic and homogeneous. This would go against observations. Thus the boundary condition too must respect this. But I know how to apply killing vectors on tensors not boundary conditions. How does one then proceed to find all possible boundary conditions which leave preserve isotropy and homogeneity? | 0 |
Today, someone asked me if the pronunciation of the "c" in "exacerbate" is an /s/ or a /z/. In fast speech, it seems indistinguishable if I substitute /z/ for the /s/ , which is the standard dictionary pronunciation). Are both pronunciations acceptable? I did some digging and discovered that between two vowel sounds, the phoneme is voiced (reason, cousin, teasing) , but I'm not sure if this is a hard and fast rule. | 0 |
According to the special theory of relativity, in moving body all physical processes are slower than they should be for a stationary body according to the time counts of a fixed (laboratory) frame of reference. In the case of moving mechanical clock we have changes in rate of the clock (according to mentioned above mechanical clock ticks slowly). In other case (for other types of clocks) we have the same changes too. But what changes do we have in the case of moving light clock if speed of light is constant? Thanks. | 0 |
Another weird question, I know, and may sound simple but I'm now trying to see why a lot of the things that we usually do without thinking, have some sense in physics, like this one. Let's say you are in a deep pool, and you are covered with water entirely but, you raise your hand above the water, what happens in the water is that your body actually goes down and sinks. Why is that? Like why by putting some parts of our body outside of the water level makes us to go down in the water? I know it may be simple but I want to know, is it because we are like "lifting" in some sense, our own arm, so it makes us to go down? | 0 |
When it comes to the reciprocal space of twist bilayer graphene, there is a very typical picture: In this picutre it shows the hoppings bewteen the nearest Dirac point between two layers. And there are six hoppings since there are six Dirac points. And these two Dirac points then form the new moire first brillouin zone of the twisted bilayer graphene, as the picture show: But I don't understand how the brillouin zone of the twisted bilayer graphene is derived. Because the reciprocal space is not even derived since the moire sublattice is not clear in the arbitrary angle. So how to derive the first brillion in formal for arbitrary angles for twisted bilayer graphene and what the reasonibility of the above picture with respect to TBG? | 0 |
Is it right to say diffraction is a geometrical optics phenomena and scattering a wave physical effect? I am considering a finite-length conducting plane and supposing a wave hitting the surface and reflected upon. In my opinion in addition incident wave should excite current sources on the plane resulting in a traveling surface wave. Upon reaching the edge wave they should scatter; if I assume very thin edge, but in many literature its said diffraction of waves is occurring at the edges. What will be correct from a physics point of view? Thanks | 0 |
When we try to form a real image on a screen by a convex lens, we place the screen at a distance where the image is focused. But if we try to place the screen at a distance less than the distance where the image is focused(refracted rays still fall on the screen) so will the image appear on the screen or will screen be blank? If image does appear how will we calculate its magnification and position? | 0 |
I am interested to see if anyone can direct me to a text on using limits and integration in the "Error-Accumulating Real Numbers" field structure. This field consists of the real numbers, but the accuracy of a value diminishes as the reported precision increases, so the error associated with a particular value increases as the precision of reporting on that value becomes greater. How would one go about taking limits and performing integration on such a field? Is it possible? | 0 |
The classic plate experiment highlights how omitted wavelengths of light create an energy differential and pressure. This pressure is dependent on the distance between the plates, including how this distance determines the omitted wavelengths of light. Could the equation be generalized for any case where wavelengths differ and an energy differential exists? E.g., redshifted cosmological objects being acted on by light sources from our local frame of reference? | 0 |
When we see an object in a spherical mirror, the different parts of the object has different pictures which are also at different locations compared to each other. The lights that go from the tip of the object reflect and intersect at a point. But the lights that go from the middle of the object reflect and intersect at a different point. We can emit lights from each part of the object, and all of them reflect and intersect at different points. So how do we see the picture of an object as a whole thing in a spherical mirror while the different parts of the object have different pictures? | 0 |
among the elementary function sets: Polynomial Trigonometric function Exponential Function Hyperbolic Function I don't see the development of algebraic identities, and then the detailed construction of various problems of solving equations, proving identities and simplification for any of their inverse algebras except for the exponentials, in the case of logarithms. What makes logarithms more deserving of this treatment than say, the inverse hyperbolics? I read on wikipedia and actually found some obscure, but few inverse hyperbolic algebraic identities, same for trig. But I've never seen an algebra problem on them, especially in standardised tests, whereas everybody is familiar with logarithmic algebra. Why is it that out of the set of elementary functions, logarithmic algebra occupies a special place out of all the elementary inverse algebras? | 0 |
If visible photons don't interact with the valence electrons in glass due to large band gap, then how do you explain the slower speed of light in glass the way classical em wave explanation does? Does the interaction (non-orbit shifting) take finite time to complete and thus slowing down the photons? Or is it just phase speed that's retarded, not the individual photons? We can test these two theories with for example a laser pulse through glass rod. | 0 |
if we have two electrons with their spins entangled like this: And if we measure the spin on the left electron, then right electron spin also change like this: So, my question is, do this spin change on the right electron can cause a chain reaction in other particles near to it?. And what forces will be involved in that chain?. I'm curious on why stimulus in the brain are localized when we aren't aware and propagated when we are. | 0 |
I have been provided with question in Functional analysis which is stated as below: I also have been provided with a solution which is given by the below picture. Now what they have essentially proved is that all the p norms are equivalent to each other by trying to make it bounded by some constants. My question is that how does it prove that convergence with respect to p-norm is equivalent to the convergence of individual components. Note I have posted image as I am new to math stackexchange. I know we are supposed to write latex. Please ignore for this time and provide me with proper argument instaed of downvoting the question | 0 |
Can we join two sentences with a comma if written in a conservational tone? Is this sentence grammatically correct? We also need to remember that donations need not be strictly only in cash, they can also be in kind such as making aircraft or helicopters booked in the name of some company or individual, being provided to a political party for its use. Source: Is There Life After Electoral Bonds? | 0 |
I wanted to know if there is a general formula to figure out the amplitude of an image formed if the object performing SHM about the principal axis or perpendicular to it at some position of a simple, Concave, Convex and all lenses (biconcave & convex,plano concave & convex, concavo-convex and convexo-concave). One numerical I have solved only involved axial SHM (about the principal axis) and involves a simple multiplication of the image's magnification and the objects oscillate along the principal axis with some amplitude. Why would we use its magnification, why wouldn't the image just have the same amplitude? | 0 |
I'm interested in how people just generate a question from scratch,(i'm preparing for indian highschool level competitive exam "iitjee"), i think people don't just start writing random stuff and label that as a question but, there are only four things i can think of they are using geometry some sort of inequalities complex numbers somehow algebra But i don't know how to generate trig questions from it, if anyone could help in giving some examples and thought processes it would be much appreciated. (Seen my teacher creating questions from Jensens inequality, mth power theorem,am-gm-hm-qm inequality,complex number) (It was my first time asking questions please ignore if any mistakes are made) Thank you! | 0 |
Consider a free body, not hinged about any point. If a force is applied to one end of the body, the body has a net nonzero torque about many points in space. About which will it rotate? Am I wrong in thinking that it will rotate at all? Note that I am not asking about a couple, but a single force. I asked a similar question a few days before, but it got closed, with links not at all answering my question. | 0 |
Jordan rolls eight fair dice, computing the sum of the numbers on the top of the dice after the first three rolls. What is the probability that Jordan is able to find at least one way to pick exactly three of the latter five dice in such a way that the sum of these three dice is the same sum as that of the first three dice? | 0 |
I would like to know if there is a relation between bounded variation of functions and bounded variation in sequences. I know one can not directly correlate the concepts but if we consider the Fourier series of the function of bounded variation, what can be said about Fourier coefficients, would they be of bounded variation (sequence definition) and what about the vice versa case? Are there any articles or books related to interlinking these concepts? | 0 |
A frame of reference is the perspective you have on a happenstance. But isn't it a viewpoint or point of view? As in, a literal point, from which something is observed? If so, why is it called a frame and not a point? Does frame of reference literally crops a section of existence as the perspective of observation? Why is it one phrasing over another? | 0 |
If a photon has a wavelength and a frequency and we depict a graph with multiple hills and valleys like done in basically every explanation regarding photons and their wave/particle behavior, like in this one. is it correct to say that one photon (as simplified as it is) is stretched from one hill to the next? And multiple of those sections are either multiple photons behind each other (when the sun emits them) or the trail of one photon as a record in space or time(depending on what one wants to depict). Or is one photon the entirety of those many hills and valleys? My understanding is, that one photon is one part from hill to hill or valley to valley, depending on how you look at it. | 0 |
For a set A, we are incrementally building a basis for A. Suppose some oracle keeps giving us new vectors from A that are not spanned by our partially-built basis. There must be some theorem that tells us this constructive procedure of adding new linearly independent vectors will always terminate after the same number of vectors are added (no matter what vectors that oracle gives us), and all sets constructed this way must form a basis for A. What is the theorem? Is it in Axler? | 0 |
I am no scientist, but I do love science as well as the unknown. Are there laws of creation for biological life? Would it be safe to assume that our bodies are made up from things that came directly out of the big bang and over time made connections through atoms and adjustments through evolution to achieve consciousness? I have much more but I'll keep it as simple as I can for now. | 0 |
A small circle is tangent to the lower right quarter of a larger ellipse. The ellipse is straight (not rotated), and its lowest point is centered at origo. The following is given: "a", the axis of the ellipse along the x axis. "b", the axis of the ellipse along the y axis. "r", the radius of the circle. "h", the top y coordinate of the circle. I am seeking the x coordinate of the tangent point between the ellipse and the circle as a function of a, b, r and h. | 0 |
Dirac's initial interpretation of antimatter is the existence of Dirac Sea. However, it doesn't work for bosons since we can't invoke Fermi's exclusion principle. Goldstone boson can be emergent but it's neutral. Xiaogang Wen's work also revealed the possibility of an emergent QED structure from string-net condensation which shows fermi statistics and gauge interactions can be emergent. We also see emergent Lorentz Invariance in the low energy area of condensed matter system. W bosons are charged bosons. It seems impossible to me for charged boson to fit into Xiaogang Wen's "it from qubit" fantasy. Does anyone know the approach to this or related literature? | 0 |
So if our eye is considered a lens, a parallel beam (sort of like collimated light from a flash light) should converge to a single point, the focal point. So does that mean our eye will see a finite parallel beam as a single dot? That seems contradict real life experience, where I still see the parallel beam as a beam with finite width. What gives? | 0 |
After reading the paper On the Expressive Power of Homomorphism Count, I was wondering if there were some nice material I could read trying to study graphs from a categorical point of view. Stuff like trying to make it in an abelian category, looking at exact sequences of graphs (maybe you'd need to consider some kind of pointed graphs category), maybe defining stuff like Ext groups and studying them. I hope my question makes sens. Thanks in advance for any answer. | 0 |
Whether it is Orion or Sagittarius, the speed relative to me is clearly faster than the speed of light. These are not inertial systems, so they are not subject to the constraints of special relativity, but does the fact that their apparent velocity is a circular motion exceeding the speed of light cause any kind of apparent change in time for celestial objects if the argument is based on a celestial coordinate system? They at least don't seem to be unable to follow, unlike the laser beams I shot at the moon or something. | 0 |
When I was reading the calculus of Variations chapter in Classical Mechanics by John R. Taylor, he mentioned that cart rolling back and forth on cycloid-shaped track are exactly isochronous (period perfectly independent of amplitude). As I was trying to solve this by the original integral, I find it hard to compute and the normal Casio type calculator cannot solve it as well, also I sought help from websites like Integral Calculator, the result function is not independent of the starting angle I set. Can someone help me, great great thanks! | 0 |
I'm trying to make a comprehensive decision tree for finding integral/improper integral convergence. The goal would be a comprehensive "guide" or list to follow in order to determine the convergence without having these automatisms already learned. Here is what I have made currently: Decision tree Are they any better ways of doing this? More optimized ? How can I make this tree more complete, more accurate ? Apologies if language is off in the image, I'm not great at this. | 0 |
Aero is not my speciality at all so apologies if missed anything. But when looking at potential flows, i thought the whole point is for there to be no rotation at any point and its that reason the velocity can be described by a scalar fuction at any point, yet the vortex flow has a point of curl in the center and hence circulation. I noticed in J.D Andersons aero book that it is this particular flow that allows for lift in invicid flow which greatly confuses me further. Is there some hidden explination behing the vortex element? Appreciate the comments. | 0 |
I am not getting the following sattements related to contact force and normal force which are: If the direction of contact force cannot be determined, it should be shown as two components. If perpendicular to the surface of contact cannot be drawn, the normal force will act perpendicular to the surface of the body. If neither can be done, normal force has to be drawn as two components- one in the X- direction and one in the Y-direction. The forces acting along the X and Y directions are independent of each other. What does these following satements are trying to explain? | 0 |
So I think I understand what binomial coefficients are, "K number of combinations that can be made from set N". However, I keep seeing examples demonstrating K being the number of successes against the number of outcomes. However, my thinking is by the logic of the first example I gave, when finding the number of combinations Tails Tails would be included as it is a combination that can be made from set N. However, this does not feature a heads and is not a success. | 0 |
I would like to reference addresses throughout a document and as an appendix generate a list with all the address entries used and the link to the places in the document where they were used. Just like it is done with a bibliography. I'm actually thinking it'd be the easiest to use a special kind of entry and store them in a bib file, and then use it as a list of citations. How would you do it? Many thanks! | 0 |
Suppose We have a charged rotating cylinder such that the magnetic field inside it is the same as a solenoid of the exact same dimensions. Obviously, the current per-unit length for both will be the same. Now, what can we say about the magnetic flux in the cylinder since there is no n (turns per unit length)? What can we comment about inductance? It depends on n and not current. | 0 |
I want to know if the verb seem can be used only for observable things? For example, if I guess the computer hard disk is failed doing some action and has some logical issues can I say: "It seems the hard disk has logical errors."? In this case, no physical failure is not observed on the disk but I know something is wrong with it. In case the "seem" is not suitable, what alternative verb do you suggest? | 0 |
I am about to compile a number of different published articles into a single thesis. While each document on its own can compile and produce a PDF, there are several macros files (shorthands for various formulas) that are inconsistent between them. Is there any way to do this with the least amount of change to each latex document? In particular, is there a way to include the macros "locally" for each article so that they don't conflict? | 0 |
As the name suggests, I am trying tio draw in TikZ the following figure for a surface current distribution (I am used to drawing with hand, so I find the switch to the digital a bit tough): The striped region is a urface that is covered with current densities J, and the second image is a representation that gives an idea on the relation of all the vectors involved. The dashed line between A and B is an "cross-section" that helps to calculate a line integral with the element being dl, and the vector n is a normal vector to the surface with u a vector orthogonal to it. Thanks immensly, and have a wonderful day. | 0 |
Is there an easy way to list all appearances of all words in the text of a LaTeX document that occur before a makeindex entry for that word arises in that document? When we move text around in a document, we can find that we have moved the definition of a technical term later in the document than one of the instances of that term being invoked. We cannot completely automate the task of eliminating these errors, because the same term might have a technical meaning defined somewhere, but also a common meaning, and the common meaning might be the meaning intended in an instance occurring before the definition. Still, TeX could help by making a list of these, so we could check. | 0 |
In a theory that predicts gravitons, shouldn't the background be flat and gravitational interaction then be modeled as a scattering event? Answer included below. Credit to /u/broguetrain on Reddit for providing the answer when I asked on there some time ago. I wanted to post this Q&A here (with some edits for clarity) due to recent drama on Reddit so as to assure my ability to reference it in the future. I do encourage additional answers on this that might provide further useful details. For example: elucidating on how specific metrics can be described as the coherent state of strings in the graviton state. | 0 |
their reasoning was that when the bike lean towards horizontal the reaction acting on the bike by surface will act in an angle through the center of gravity of the slanted bike(not perpendicular to the surface). therefore the horizontal component of that angled reaction will provide the centripetal force even though friction is not present. they also said that if the friction is present this component will be added to the friction and their resultant will act as centripetal force. i find this hard to believe.i think it is impossible to turn on a frictionless horizontal surface. can someone please help me find the correct answer? | 0 |
Or at least I think it was Pratchett taking a potshot at religion (exact wording unknown either): "When you got them by the balls, you, uhm, got them by the balls." Note that both parts of the sentence are metaphorical, meaning about "When you control their sexuality, you control them totally". Which rhetoric figures are involved here (is the one metapher more, uhm, metaphorous than the other since the first part involves actual balls, at least pars pro toto or so)? Seems to be quite a lot... | 0 |
There is a misconception that electrons push each other from their mutual repulsion within a circuit. Rather they are pushed by the electric field. I also understand that the electric has the energy rather than the electrons being charged carriers. However, I can't seem to understand why we need wires at all when energy is in the fields rather than the electrons. What is flawed with my logic? | 0 |
Basically I know how "a" and "an" are used: a member an adult member but how is the same handled when the middle word is inserted parenthetically or even in brackets: I met a member of the club. I met a/an - adult - member of the club. I met a/an (adult) member of the club. Should there be "a" used, because the main phrase is "a member" or should "an" be used because the adjective starts with a vowel? And is there a rule to quote? | 0 |
I want to drop a cup of water with a ping pong ball within it so that it falls straight (as much as possible) and that I can reiterate the experiment rigorously... I've seen someone using magnet and a specific system that sadly I cannot build at home. My idea is to hold the cup and trigger something that let fall the cup with the ping pong ball but nothing good comes in my mind. Do you have any ideas? Thanks for reading | 0 |
I was reading an article about high density housing and/or constantly being online and came across a single word I had to check the dictionary for and it was used to mean "the absence of a community spirit". e.g. "The x caused by the complex housing situation." I have had no luck with antonyms for community or synonyms for diaspora. I can no longer remember the word or the article. It may mean the degradation of community or the circumstances preventing it. What word is used to define this asocial vacuum? | 0 |
I look how to implement the algorithm (program) for solving so called Zebra(Einstein) Puzzle. For that, i look for some formal or mathematical representation of conditions in this puzzle. Can you suggest possible ways to represent it, while this representation should makes easier to solve that? Of course, do not suggest the trivial forms, like list of all possible variants, this is not efficient if there are too many variants. | 0 |
I've been attempting to get a row of dots from the end of the equation right to the equation label, that allows the reader to easily trace along from, say, an equation on the right of the page, muuch like the format commonly used for contents pages; headings with a row of dots leading to the page number(s) so that the reader doesn't get lost, trying to trace along the "line" with no guide per se. Thanks | 0 |
The ant on rubber rope paradox says that an ant moving along a rubber rope that can infinitely expand will reach the other end of the rope regardless of how fast the rope expands and how slow the ant moves. Why then multiple sources say that there is cosmic event horizon, and two persons at some distance exceedidng Hubble limit would not be able to meet? | 0 |
Is there a way to calculate equivalent parameters of a few RL links for direct current circuit (like on the generalized example on the image below)? So far I've studied that known formulas for series/parallel connections of R and L elements cannot be used because it's not R and L elements, which are connected in parallel and series, but RL elements (as a single entity), which can connected in parallel or series. | 0 |
My former college is starting a departmental journal which I am editing and typesetting. I have edited and typeset every contributed article individually using the article class and initially tried to bring them all together using the combine class then individually tried the subfiles and standalone packages but none of it worked. So finally I decided to use pdfpages package and include all the articles as pdfs in my main document. Now, each included pdf article has a separate title and author BOTH of which I want to add to the main toc. How do I do this? | 0 |
A large part of the computational physics literature relies on solving Newtons equations for deriving phase diagrams and related properties of the LJ system. In many cases this approach does not require justification since one could be interested only in the dynamics of the system during a short time. But this is not the case if one is interested in caculating partition functions. So I have not found any established result to ensure that this approach is sufficient for sampling the phase space and calculating partition functions. | 0 |
The universal law of gravitation of Newton calculate the intensity of gravitational force by the radius and mass of an body.. so in a black hole there is very much small radius and a large amount of mass... So I think newtonian gravity would predict large amount of force.... That is similar to the great pull of black holes due to gigantic space time curvature... | 0 |
I now have a point located at x, and the value at that point is q(x). I want to discretize the point to the surrounding grid points and maintain a Gaussian distribution. A one-dimensional grid is fine. Is there any generally recognized good discrete method? Thank you. As far as I know, B-spline does not satisfy Gaussian distribution, so B-spline is excluded. One method I found is D.E.Shaw's Midtown-splins, but it can only reach the third order, which cannot meet my needs. What is a better discrete interpolation method? | 0 |
Can anyone suggest existing technologies that must account for electromagnetic momentum? I believe one example to be confinement in nuclear fusion; but momentum there appears in an averaged form, as pressure. Just to give an idea of what I mean with "existing technologies": general-relativistic time dilation has to be concretely taken into account in any phone's GPS. (Edit: many excellent answers have been given, it's really difficult and partly meaningless to choose one as "the" answer! I chose JEB's one mostly because it is about a macroscopic effect and about a directed form of electromagnetic momentum, rather than more "averaged" forms closer to electromagnetic pressure.) | 0 |
For many (!) years I have written papers in MS Word with numerous embedded equations generated by MathType software. MathType prior to its recent acquisition by Wiris was able to function as a standalone equation editor and save equations as pdf files that could be embedded in Word, and edited either within Word on independently in the saved pdf format. The new version of MathType is an absolute disaster: the interface is pathetic with many controls of sizing and fonts lost, the generated equations are bit-mapped (not vector graphics), etc, etc. I hope to switch to producing all equations in manuscripts with LaTeX, but wonder whether some version of LaTeX can generate Word-embeddable pdf files, and if so what version(s) of LaTeX are suitable. Thank you! | 0 |
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