Symmetry Definition and 907 Threads

-Is it possible for two objects to have symmetrical geodesics in which each accelerate with equal magnitude but in opposite directions? If not why not? -If so, how can both see each others clocks run slow? Would one have aged less than the other when then they reunite? Which? If not what...

Homework Statement I have a shape about the origin. It has rotational symmetry but not reflectional symmetry (its an odd star shape!). I have to write down in standard notation the elements of the symmetry group and I have to construct a caley table under composition of symmetries. I...

is super symmetry real or has been predicted by string theory?

Hi! Although nobody can see the shape of elementary particles, we always assume that their shapes are symmetrical, for example, sphere. Why? Is the symmetry a law? Otherwise, are there any other reasons? Patrick

I know there are 3 kinds of symmetry: x-axis, y-axis, and origin. So, if you test the function for symmetry and it turns that it has one of these, does it mean that it cannot have the others? Therefore, one function has one type of symmetry only?

hi, I am trying to interpret some data which have been calculated for IR/Raman but I don't know how to interpret them exactly. The schema says mode \nu 1 b_u 82 1 a_g 216 2 b_g 239 I presume that the u/g are gerade/ungerade from the bonding/antibonding wave functions but how to...

Hi all In almost all the formulae related with symmetry, we use pi. For example, in case of circle, we use pi, and in case of sphere we use 4*pi. e.g. E (electric field)= (q * qo) * 1/(4*pi*eps* r^2) A (circle)= pi*r^2 A (sphere)=4*pi*r^2 My question is: How does pi signify...

For each symmetry operation R acting on a physical system,there is a corresponding unitary transformation U(R). But what is the principle for such relation? an example is that : for a continuous symmetry ,we can choose R infinitesimally close to the identity ,R=I+eT ,and the U is close to I...

http://www.symmetrymagazine.org/cms/?pid=1000475 click to enlarge---portraits of the fundamental particles http://www.symmetrymagazine.org/cms/?pid=1000480 Roz Chast did the cover of May issue of Symmetry (a joint SLAC/Fermilab publication) and illustrated the article on Dark Energy She is a...

Ok, so if you have two electrons near one another, they will start to repel one another and separate as time goes on. Now if you reverse time, they will move towards one another. But it is said that antimatter can be viewed as matter going backwards through time. Now if this is true, this would...

Homework Statement We are to show that (A)(A^T) is a symmetric matrix using tensor notation. Where ^T denotes TRANSPOSE Homework Equations The Attempt at a Solution I did it in the following way: Let P=(A)(A^T) Then, p_ik=(a_ij)(a_jk) Where A=a_ij and A^T=a_jk =(a_jk^T)(a_ji)...

I do not know the Lagrangian or Hamiltonian principles of mechanics. However,I came to know that conservation of linear momentum,angular momentum and conservaton of energy lead to homogeneity of space,isotropy of space and homogeneity of time.Can anyone show why it is in purely Newtonian terms?I...

If there were no symmetry theories in physics would our practical understanding of the world be worse - is there any everyday device/machine that would not have been thought up and invented without symmetry theories?

Hi all, I was thinking of symmetries today and this kept bugging me. I wonder if anyone can help me with this. Consider the symmetries of a triangle. You can do 3 rotations and 3 reflections to get them all. Number the vertices, create an ordered set with 3 elements that contain the...

Hi! I read that in an 1D potential, the solution for the Schrödinger equation is always either symmetric or antisymmetric if the potential is a symmetric function: V(x) = V(-x). How can I proof this? Thanks, for ur answers!

I can't quite remember where I got this idea, but once my brain remembered one point about higher dimensions(that of how each higher dimension, at least in terms of the first three dimensions, is at 90 degrees from one another. Well, actually how can you say the first dimension is 90 degrees...

How would one know in general, whether an original gauge symmetry in the theory is still gauge symmetrical after symmetry breaking? I mean is there a theorem or something like that? And the other way around, is there a general way of knowing whether there is the possibility of a hidden, i.e...

My dream engine, needs a dark matter governor to prevent it exceeding its designed rpm limit, unfortunately no one makes them yet. It will produce dark energy as the motive power, but alas the formula for its production, or its existence is not known. It will, hypothetically, if it runs...

I find it awkward that quarks are in fundamental representation of SU(3) while gluons are in adjoint representation of SU(3). Is there a reason as to why this is the case? Why aren't they in the same representation or in the current specific representation?

The law of conservation of momentum has never been observed to be violated.In quantum mechanics conservation laws relate to symmetries.So is the existence of the law of conservation of momentum due to the fact that a symmetry exists, or does a symmetry exist because the law of conservation of...

An isolated electron and positron depict an exact two-fold symmetry. Are there any examples in physics of a truly triplicate symmetry? If not, what constraints are there that prevent it?

I have a form factor that only depends on the momentum transfer q, this is symbolised by writing the form factor as F(B]q[/B]^2). if i have a spherical symmetric distribution of charge, f only depends on the radius; r = | q| Then integration over all solid angels yields...

Homework Statement A square plate of edge length 9.0 cm and negligible thickness has a total charge of 6.3 x 10-6 C. (a) Estimate the magnitude E of the electric field just off the center of the plate (at, say, a distance of 0.50 mm) by assuming that the charge is spread uniformly over the...

Hi, I have done classical symmetry breaking and now want to understand the quantum one. I have seen the statement that the symmetry is broken if and only if Q|0> not 0. Where |0> is the vacuum and Q is the associated charge of the broken symmetry. Why does this imply symmetry breaking? The way...

Hi, I recently saw an author make the following statement: If the symmetry leaves the 1-particle states invariant then its associated charge Q acts on the 1-particle states |p> such that Q|p> = 0 This statement is nontrivial to me, so if anybody could show me how it works please let me know.

Hi, I have to determine the symmetry group of cyclopentadienyl(assumed to be planar and symmetrical) and I should use Huckel theory. Is there a systematic way to determine the symmetry group and is it possible to use software to determine the symmetry group. Thanks in advance

Is it possible to show directly from Newton's Laws that conservation of momentum and energy follow from principles of symmetry?

I understand that E^2 - B^2 is invariant under various transformations. If we consider the vector ( E, B ) as a column, then E^2 - B^2 is preserved after mutiplication by a matrix - | cosh( v) i.sinh(v) | | i.sinh(v) cosh(v) | I think this transformation belongs to a group...

What symmetry gives probability conservation? Or, what symmetry does probability conservation give? I have been trying (unsuccessfully) to find an answer to this question. I think the question makes sense. That is, I can't see how the situation is different from, for example, that of spatial...

A curve is given by the parametric equations x=t^2+3, y=t(t^2+3) a)Show that the curve is symmetric about the x-axis. b)Show that there are no parts of this curve where x<3 c)Find dy/dx in terms of t, and show that (dy/dx)^2 greater or equals to 9. Sketch the curve by using the above...

Could somebody please give me a definition for the term gauge symmetry in contrast to any other symmetry? Is the decisive difference that a gauge symmetry is local i.e. a function of the coordinates in contrast to being constant? I would also appreciate it if it could be pointed out how the...

I recently posted a question on energy and matter and I got a very good answer to that one so I thought another one wouldn't hurt. I understand that time symmetry is what makes all conservation laws possible as is stated in Noether's theorem. Time symmetry is what explains the conservation of...

I hear all the time people saying things like "groups are the algebraic equivalent to the notion of symmetry". Yet I don't think I've ever really understood what was meant by this. I'm familiar with groups of symmetries (like the dihedral groups), but in these cases, to me it just seems like...

Homework Statement Does the molecule in the file attached have an enantiomer? Homework Equations The Attempt at a Solution I think I can draw an internal symmetry plane to divide the molecule into 2 equivalent parts, but then again, it doesn't seem quite right to me. Building...

I'm trying to solve a special integral. \int{\frac{1}{1+[Tan(x)]^a}}dx So far I've tried constructing a function F(a) and differentitating to show that it is a 0, hence any a would result in the same answer. Thus chose a = 2, and solve it quite easily. Although, all my arguments rely on...

Ok , during my study , I read that the bodies which are rotating spherically symmetrically do not emit GW;s as in don't dent the spacetime memberane...same is with the bodies moving with uniform velocity ...why is that??...has it something to do with conservation of angular momentum??:blushing:

I have been trying to understand how our ocean tides work and read about the effect of our moon's and sun's gravitation. I have learned there are diurnal, semi-durnal and mixed semi-diurnal tidal patterns When the moon is directly overhead equatorially (near side), I've seen illustrations...

Previously i learned from maths that the complex inner product satisfied skew symmetry and linearity in the first component, ie - <aA+bB,C> = a<A,C> +b<B,C> But after studying Shankar in quantum mechanics, he claims the linearity is in the ket vector, ie - <A,bB+cC> = b<A,B> +c<A,C> which...

Hello ! I'm having trouble with the symmetry of the stress tensor. What it means physically? In the demostration of the symmetry my book applies the angular momentum equation to a third material volume (a cube, length L). In the final step we have: 0 = \mathop {\lim }\limits_{L \to 0}...

I'm looking for a good tensor reference book that provides insights into the following areas of tensors: 1. Symmetries & how to extract them. 2. Full tensor visualisation eg. how to visualise the stress tensor in its 9 component form without resorting to a split into 3 simultaneous...

Why do operators representing some symmetry commute with the Hamiltonian?

Q is a conserved charge if \{Q, H\} = 0 Show that q+\epsilon\delta q satisfies the equation of motion. \delta q = \{q, Q\} I couldn't find the proof. Anybody knows? My workings: \delta q = \{q, Q\} \delta\dot{q} = \{\{q,Q\},H\} = - \{\{Q,H\},q\} - \{\{H,q\},Q\} \delta\dot{q} = \{\{q,Q\},H\} =...

Like nested dolls, these black holes appear coexisting concentrically where the central stelactic (stellar-galactic) black hole mediates a symmetry between the other two. For instance, consider how stelactic Hawking radiation manifests under inversion of its event horizon. The events within...

Dear PF, I don't know whether this is the right place for such question, but how to reduce symmetry suppose from SU(2) symmetric Lagrangian down to U(1)? Thank you

These forums help me practice my communication skills, thank you to those who helped me reword the following little document. __________________________________________________________ I am going to try and deduce as much as I can about the nature of matter from symmetry and the galilean...

Let be a differential equation : y^{(n)}=F(t,y,\dot y ,\ddot y , \dddot y,..., y^{n-1}) then if we propose a Lagrangian so its euler-Lagrange equation gives: \sum_{k=0}^{n}(-1)^{n}\frac{d^{2}}{dt^{2}}(\frac{\partial ^{n} L}{\partial \ y^{n} })=0 The differential equation can be...

"Against Symmetry" Smolin in Paris June 14 Prof. Smolin will be speaking at an amphitheater of the Ecole Polytechnique (Paris version of MIT). The talk is part of an historical controversy. Here is a short advance summary of the talk copied from Christine Dantas' blog...

Ok, the problem is that I don't have enough time or money, so I want to be somewhat careful in what books I buy. I am looking to purchase a few books on modern physics that discuss new ideas in physics, and I've found many books with good reviews that cover the topics that I'm interested in...

Electrostatic conundrum: How "brute force" and symmetry arg. give different answers! Hello everyone, this is my first post -- and an interesting one (or so I think). **Note to Mods: this is NOT me asking for a solution to a HW type problem -- I know and have the solution already -- rather...

As someone returning to a study of physics after many years, I would appreciate any help and comments on my unresolved questions after reading “popular science” type information regarding quantum effects. In considering (that old chestnut!) the “twin slit” experiment to demonstrate the quantum...