Symmetry Definition and 907 Threads

Reading this article: http://arxiv.org/abs/math-ph/0102011 made me wonder: 1.) So, it appears that Galilean transformations are not the most general symmetry transformations of nonrelativistic mechanics. Fine. 2.) The article states that the two additional symmetries are the nonrelativistic...

Please teach me this: It seem to me the Ward-Takahashi is validated by the renormalization, if the theory can not be renormalized the proof of Ward identity is failed.In QED the Ward identity is validated by electrical charge renormalization. The Ward-Takahashi implies a current...

Please teach me this: For gauge symmetry fields,only one of any elementary subconfiguration of the whole configuration covers the all physics of the field.So we need to cut off the redundant configuration.It seem to me,in a loose sense,there is only one way to cut off the redundancy(the gauge...

I'm looking for a summary of what invariance or symmetry of the Action in Feynman's path integral has on the equations of motion and on measurement. Do different symmetry groups of the Action integral result in different equations of motion for different particles? Is the least action principle...

Why is there no gauge symmetry for spin-1/2 fields? Has gauge symmetry to be related to spin-1 fields/ particles? thanks

Hi, If I have a Lagrangian of complex scalar field (just U(1) local invariance). And I know that phi^star describes field with -e electric charge and phi describes field with e electric charge. How do I apply "charge issue" when I write Lagrnangian after spontaneous symmetry breaking in...

We know velocity/momentum and magnetic field both are odd to time-reversal operation. Then how is the time-reversal symmetry broken in quantum Hall effect since magnetic field is always coupled with velocity/momentum?

Well, I've really been getting into Quantum Relativity and Quantum physics, and one thing really just seems fuzzy to me. Super Symmetry. Wikipedia goes into too much math and history and blah blah blah... Other sites just say the history of discovering super symmetry Some sites are...

dy/dx = (2/pi^(1/2))e^(-(x^2)) eq 1.17 My book makes a statement about the symmetry of the family of solutions to this diff eq I don't quite understand. "Symmetry. If we replace x with -x on both sides of 1.17, the right hand side is unchanged but the left hand side changes signs. So...

Hi With the Bose-Hubbard Hamiltonian (BHH) being invariant under a U(1)\equivO(2) symmetry transformation, it is said that the hopping-term in the BHH tends to break the U(1) symmetry as the system leaves the insulating phase. This is not clear to me. However within the mean-field...

Hi there! You have a particle moving to the left as time goes on. Now if you reverse the time the particle will move to the right. Does it mean that the system is not symmetric under time reversal?

Homework Statement Two players A and B place in alternated way pens on the quadratic table. http://img37.imageshack.us/img37/3051/grazn.jpg (my table is not quite quadratic as it should be) The only condition is that the pens cannot come into a contact with one another. The player who can...

Homework Statement Show that symmetry operations for en greek vase build up a symmetry group. Homework Equations For en greek vase we have \Gamma=[e, C_{2},\sigma, \sigma^{'}] And there are 3 conditions which must be fullfilled so that the elements will create a symmetry...

Homework Statement Hi, I need to proof the covariance of the equations of motion under an infinitesimal symmetry transformation. Homework Equations Equations of motion: E_i = \left(\frac{\partial L}{\partial \chi^i}\right) - \partial_{\mu} \left(\frac{\partial L}{\partial \chi^i_{\mu}}\right)...

Homework Statement How can I tell if the following equation is symmetrical and whether it is even or odd? Homework Equations f(x) = x^2 - 6x The Attempt at a Solution I would guess that it is symmetric about x = 6 but that's not what the book says.

Homework Statement Assuming that transformation q->f(q,t) is a symmetry of a lagrangian show that the quantity f\frac{\partial L}{\partial q'} is a constant of motion (q'=\frac{dq}{dt}). 2. Noether's theorem http://en.wikipedia.org/wiki/Noether's_theorem The Attempt at a Solution...

Question 1: I am aware the Higgs lies in a chiral supermultiplet, but I realized I don't have an intuitive idea of i) how many Higgsinos there are (since the MSSM has 2 complex isodoublets) ii) how many Higgsinos there are after EWSB and you gauge away three of the scalar fields iii) their...

Is the principle of symmetry is universal? i.e every particle has an anti particle,similarly maxwell derive his equations by using symmetry.

Hi I've heard this term a few times and I couldn't find a definition in textbooks.. What is the definition of Particle-hole symmetry? I gather it's something like taking c -> c+ , but is there a definition of an symmetry operator that commutes with the hamiltonian or something? What does it...

Basically, the title says it all. I've never heard of Noether charge corresponding to gauge symmetry of the Lagrangian. Is it because gauge symmetry isn't the "right type" of symmetry (one parameter continuous symmetry) so the Noether theorem doesn't apply to it?

Does anybody know a good (short) reference which explains how a top-quark condensate acting like a "bound state Higgs" generates both fermion and W- / Z-masses?

what is meant by the custodial SU(2) approximate symmetry as a 5, a 3? it is always mentioned in the Higgs triplet, charged higgs context.

I saw this paper listed, http://arxiv.org/abs/1012.5529 Asymptotically safe weak interactions Xavier Calmet (Submitted on 26 Dec 2010) "We emphasize that the electroweak interactions without a Higgs boson are very similar to quantum general relativity. The Higgs field could just be a...

Homework Statement Let D be the triangular domain given by 0\leq y \leq3, (y/3)-1 \leq 1-(y/3). Then \int\int (e-x^{5}e^(sqrt(1+y^2)) Homework Equations The Attempt at a Solution There is a quick way to solve it by breaking apart the double integral and then, apparently the x^5...

Homework Statement Given the equation r²=25sin2Θ Asked to find symmetry with respect to line Θ = pi/2 Homework Equations w.r.t. Θ = pi/2: (r,Θ) - (r, pi-Θ) and (r, Θ) - (-r,-Θ) The Attempt at a Solution For the first case, I plugged in (pi-Θ) for Θ, but I'm confused about what to do...

I keep seeing these things being mentioned called SU(2) and SU(3) symmetry in particle physics literature. However, I don't know what they mean, and googling around just brings up pages of weird looking mathematics that I don't have the time to sift through and learn right now. Can anyone give...

Homework Statement Determine the point group of the chair conformer of cyclohexane. How many Raman active vibrations and how many infrared active vibrations might you expect to detect in its spectrum? Homework Equations (see link below) The Attempt at a Solution...

I love my nice argyle socks (which I've collected from Christmases passed). But I've noticed a weird inequality in their aging behavior. Toe holes do not form evenly on both sides of the sock. My socks are not "footed" or "handed." That is to say, I do not have a left-sock, or a right-sock...

Hey guys, i am looking for some primer on conformal, dual conformal symmetry, respectively. I have to read a lot of stuff about scattering amplitudes for uni and in recent papers people talk a lot about these symmetries... unfortunately i am not so familiar with them, so does any of you know...

I have found this small review by Witten of the arguments about B-L symmetry and its role in neutrino masses. http://arxiv.org/abs/hep-ph/0006332 I have been always amazed about the mismatch between the role of this symmetry in any attempt to unify interactions, including Weinberg-Salam, and...

In Srednicki's QFT book on page 63, figure 9.11, the diagram in the middle of the second row is a Feynman diagram with four external lines, two vertices, one internal line and one loop placed on one external line. It has symmetry factor 4. Does the symmetry facor stand for the 4 possibilities...

The Many-Worlds interpretation tells us where the information “goes” at a measurement. Does it also tell us where the information “comes from” afterward to create the new undetermined state? If it is symmetrical, then does that mean that a measurement is the result of confluence or interference...

The common understanding is that below around 250Gev the weak force gauge bosons have mass and appear distinct from the electromagnetic force, with its massless photons. And that to explain this required hypothesizing the Higgs field, which acts like a superconducting field, in the vaccuum...

Homework Statement What is the moment of inertia of a solid cylinder (of mass 8.41kg and radius 7.5cm) rotating about an axis parallel to the symmetry axis but passing through the edge of the cylinder?Homework Equations I=.5mr2, but how does this change when the axis is passing through the edge...

Homework Statement The generators of SU(3) are the Gell Mann matrices, \lambda_a. Consider symmetry breaking of an SU(3) theory generated by a triplet of complex scalar fields \Phi = \left(\phi_1, \phi_2, \phi_3\right). Assuming the corresponding potential has a minimum at \Phi_0 =...

Why do groups descibe symmetry? Why does a set which has an identity and inverse element, is closed under an abstract multplication operation and whose member obey the association law, captures symmetry? Why is that? thanks

I'm reading Roger Penrose's Cycles of Time. On p. 124 he's explaining why he thinks inflation doesn't solve the mystery of why the universe started out in a low-entropy state. He argues that a high-entropy collapsing FLRW universe would consist of "a horrendous mess of congealing black holes,"...

So I'm trying to teach myself MO Theory and Spectroscopy. I was just wondering why symmetry was so important in understanding these and what characters are used to do. I know this is a broad question, but I've been reading a lot (Cotton, etc..) so I know they have to do with integrals and...

Homework Statement I know that, \left[ {f(x),p} \right] = {\bf{i}}\hbar \frac{{df}}{{dx}} By symmetry, is it also true that, \left[ {f(p),x} \right] = {\bf{i}}\hbar \frac{{df}}{{dp}} ...since x and p are just symbols?

Hello, how do symmetry groups in the Euclidean space differ from the symmetry groups in the hyperbolic space (in the Poincaré disk) ? I've been told that in the hyperbolic case one has at disposal a richer "vocabulary" to describe symmetries, but I don't see how, and maybe I misunderstood...

Hello everyone, I was learning about the topic "chiral symmetry breaking" recently and got couple questions. I try to describe my understandings below, then list the questions: From the QCD Lagrangian level (quark level), I can understand the exact chiral symmetry exists when we take...

I was reading Hasan & Kane's review on topological insulators and right in the beginning, page 3, they say that the Bloch ground state is U(N) invariant. I do not see that. Would anyone be able to show it or point to a reference? Thanks, Jan.

Hi guys, I need to write down the positions of all the atom in LaFeAsO unit cell: Figure caption: "The quaternary equiatomic ZrCuSiAs-type structure is very simple, with only eight atoms in the tetragonal cell. The dashed lines represent a unit cell." I also have these informations...

recently i am reading chiral symmetry in QFT. Almost all textbooks define γ5 as a chiral operator without saying some reasons. i am very confused why γ5 has something to do with chiral symmetry, can somebody explain it more intuitively and physically? who first introduce γ5 as a chiral...

For the following curves i) y=x^2+4x-1 ii) y=-2+or-Square root(x+5) a) Sketch both the curves on the same sheet of graph paper- against the same axis I have done this, although I have not shown it here b) Determine with proof, whether the above curves are related. Not sure how to do this...

I was suddenly confused by the calculation of symmetry factors of Feynman diagrams. For example, in Peskin's textbook, as the attached pdf file, Below eq(4.45), he calculated the symmetry factor in detail, however, I was confused by the last 1/2 factor. I'm trying to realize this...

just got dumped out and lost my thread, so will keep this brief and add later once accepeted www.primepatterns.wordpress.com anyone noticed the symmetry of primes (well pseudoprimes if you must) starting at each p#/2 i.e. 105, 1155, 15015? they arise from the Sieve of Erathosthenes and...

I wanted to understand what symmetries the standard model lagrangian has, and what "effective" (don't know what to call this) symmetries our universe has due to the vacuum state breaking the symmetry. Unfortunately, I'm having trouble extracting that information from the Lagrangian of the...

We say that conservation of linear momentum follows from the translational symmetry while conservation of angular momentum from directional (rotational) symmetry. Can anyone explain what exactly do we mean by these kind of symmetries and how they imply conservation of certain quantities?

http://en.wikipedia.org/wiki/Landen%27s_transformation" Since both the expressions a_1 and b_1 in Landen's transformation are selected in an arbitrary manner, is it all right to define a_1 with the geometric mean and b_1 with the arithmetic mean, instead of as given in the above link? I...