Questions tagged [physics]
For questions about mathematical problems arising from physics, the natural science studying general properties of matter, radiation and energy.
194 questions
0
votes
1
answer
126
views
orthotropic materials solution of boundary value problems
What are the methods or approaches for the analytical solutions of boundary value problems in the theory of elasticity for orthotropic materials?
11
votes
2
answers
2k
views
Homotopy $\pi_4(SU(2))=Z_2$
I am a physics student, recently I read a paper using Homotopy $\pi_4(SU(2))=Z_2$, I guess mathematicians have some visualization or explanation of this result. So I come here ask for help.
CROSS-...
- 575
4
votes
1
answer
551
views
Impact of LHC on math ? [closed]
LHC (Large Hadron Collider) "... remains one of the largest and most complex experimental facilities ever built". May be it is even the most complex project in humankind's history(?).
Such projects ...
2
votes
1
answer
815
views
David Hilbert on Complex Multiplication [closed]
I have tried vainly to understand the significance of the following statement attributed to David Hilbert:
The theory of complex multiplication is not only the most beautiful part of mathematics ...
- 83
1
vote
0
answers
501
views
Distribution of random vectors
Two positive numbers $\alpha$ and $\beta$ are given. We are going to describe a process of choosing a random vector on the unit sphere $S$ in $\mathbb R^3$ (given by $x^2+y^2+z^2=1$).
A vector $u\in ...
- 143
6
votes
4
answers
709
views
Higgs mechanism from a deformation quantization point of view
Is it possible to describe the Higgs mechanism from a deformation quantization point of view? How would one do it? Are there aspects of the Higgs mechanism and Higgs particle which one may see clearer ...
- 1,222
6
votes
2
answers
974
views
Quantum mechanics basics [closed]
Hello. I'm thinking about where does the basic quantum mechanics things comes from. I mean the forms of operators and a Shroedinger equation. The more intuitive explanation is better.
To get forms of ...
- 65
0
votes
1
answer
393
views
Why is the physical space equivalent to $\mathbb{R}^3$ [closed]
I am trying to understand what would be the logical reasons behind our assumption that our physical space is equivalent to $\mathbb{R}^3$ or 'physical straight line' is equivalent to $\mathbb{R}$.
$\...
- 1,305
10
votes
1
answer
2k
views
What is the current state of the mathematics of Higgs fields?
Topical. I know there are good mathematical theories in which "Higgs" is used, in a geometrical sense. Would someone care to explain?
To clarify, I'd like to know about Higgs bundles on Riemann ...
- 12.6k
0
votes
1
answer
332
views
How the spin value is related to mathematical nature of the field?
Fields are one of the following: scalars, vectors, spinors or some Lie algebra elements, right? And it's often said that scalars are spin-0 and vectors are spin-1. So, what's idea of correspondence ...
- 65
4
votes
3
answers
4k
views
Best book for learning sensor fusion, specifically regarding IMU and GPS integration.
I have posted this in MathOverflow because the subject is primarily Math related.
I have a requirement of building an Inertial Measurement Unit (IMU) from the following sensors:
Accelerometer
...
- 141
4
votes
0
answers
373
views
Bosonic String Theory
I would like clarification of 26 dimensional Bosonic String Theory. A definition would be, that this is free bosons compactified on a torus and orbifolded by a 2-point reflection group (or ...
- 515
7
votes
4
answers
3k
views
Exercises in Lie group theory for physics
I teach a course on (Lie) group theory for physics at the level of senior undergraduates.
I follow basically the book by Georgi "Lie algebras in particle physics". So I teach them the groups SU(2), ...
user16974
10
votes
1
answer
1k
views
Self-tightening knot
Is there a way, for some finite $L>1$, to tie two length $L$ pieces of rope together, such that any finite force is not enough to pull them apart?
The type of rope I have in mind is something like ...
- 163
0
votes
0
answers
238
views
Simple question on the foundations of spin foam formalism
To make it simple, take the spin foam formalism of ($SU(2)$) 3D gravity. My question is about the choice of the data that will replace the (smoothly defined) fields $e$ (the triad) and $\omega$ (the ...
- 733
7
votes
1
answer
2k
views
Minimize Energy for Charge Distributions
I am considering [positive] charge distributions $\rho:M\rightarrow\mathbb{R}_+$ (nonnegative reals) with unit charge $\int_M\rho=1$ for convenience. Here $M$ is a nice-enough region, say a ...
- 17.5k
10
votes
1
answer
991
views
What is the "Physically Consistent" proper subset of arithmetic?
Suppose 1st-order arithmetic is inconsistent along with Voevodsky http://video.ias.edu/voevodsky-80th.
It nevertheless remains true that when you have 2 apples and 2 apples, you have 4 apples. ...
- 167
6
votes
1
answer
403
views
Orbits for homogenous complex polynomials under unitary rotation of variables
Let's have two complex homogeneous polynomials of degree $k$: $f(z_1,\cdots,z_n)$ and $g(z_1,\cdots,z_n)$. We consider rotations of variables in the form of $\vec{z}' = U \vec{z}$, where $U\in SU(n)$.
...
- 1,612
3
votes
2
answers
1k
views
Maxwell Stress Tensor and Equations in Mathematician's Language [closed]
In my language, a differential two-form on $\mathbb{R}^4$ (viewed as a differentiable manifold with coordinates $t,x,y,z$) is a differentiable choice at each point of an alternating bilinear function ...
- 15.4k
14
votes
4
answers
6k
views
Topology of black holes
I've asked this question of some physicist friends of mine and I've never gotten a satisfactory answer: What is topologically possible for a neighborhood of a black hole? To clarify, I'm curious about ...
- 203
153
votes
27
answers
50k
views
A soft introduction to physics for mathematicians who don't know the first thing about physics
There have been similar questions on mathoverflow, but the answers always gave some advanced introduction to the mathematics of quantum field theory, or string theory and so forth. While those may be ...
23
votes
5
answers
6k
views
Flux through a Mobius strip
A friend of mine asked me what is the flux of the electric field (or any vector field like
$$
\vec r=(x,y,z)\mapsto \frac{\vec r}{|r|^3}
$$ where $|r|=(x^2+y^2+z^2)^{1/2}$) through a Mobius strip. It ...
- 13.6k
3
votes
1
answer
697
views
Which motion is exclusive in 3D or higher dimensions?
Hi guys,
I have a simple question
Linear movement can be found in 1D, 2D and 3D world objects
Rotation can be found in 2D and 3D world objects.
Now, are there any kind of motion can only be found ...
- 101
2
votes
0
answers
3k
views
What is the geometric meaning of the third derivative of a function at a point? [closed]
What is the geometric meaning of the third derivative of a function at a point?
This question is now asked on the sister site: https://math.stackexchange.com/questions/14841/what-is-the-meaning-of-...
- 61
12
votes
1
answer
2k
views
Is there an analogue of mathscinet for physics?
I've been looking recently at some papers in physics, from journals that are not listed in mathscinet. Is there is a similar database for physics, with reviews and citation links? I'd like to see ...
- 8,803
15
votes
9
answers
4k
views
Newton equations, second order equation and (im)possible motions
I am am currently studying Newtonian mechanics from a conceptional and axiomatic point of view. Now, if I am not mistaken, one (but surely not all) statement of Newtons second law about nature is, ...
- 1,222
34
votes
6
answers
5k
views
Is symplectic reduction interesting from a physical point of view?
Do you think that symplectic reduction (Marsden Weinstein reduction) is interesting from a physical point of view? If so, why? Does it give you some new physical insights?
There are some possible ...
- 1,222
29
votes
3
answers
4k
views
How can simple physical "proofs" of mathematical facts be made rigorous?
Mark Levi's The Mathematical Mechanic is a book of examples of how physical reasoning can be used to solve mathematical problems; another couple of examples is in this blog post at Concrete Nonsense. ...
- 118k
27
votes
11
answers
4k
views
What kind of Lagrangians can we have?
In any physics book I've read the Lagrangian is introuced as as a functional whose critical points govern the dynamics of the system. It is then usually shown that a finite collection of non-...
- 2,641
8
votes
1
answer
432
views
Two interacting bodies in an external field
Hope, MO is the right place for this question (if not so: where would you pose it?).
Consider a two-body system in classical mechanics. As long as the interaction depends only on the distance of the ...
- 9,720
22
votes
6
answers
15k
views
Angle Maximizing the Distance of a Projectile
It is well-known that to maximize the horizontal distance traveled by a projectile fired from the ground at a given speed, one should fire it at a $45^\circ$ angle. What's less-known, though not too ...
- 15.4k
106
votes
3
answers
10k
views
Has the Lie group E8 really been detected experimentally?
A few months ago there were several math talks about how the Lie group E8 had been detected in some physics experiment. I recently looked up the original paper where this was announced,
"Quantum ...
- 20.7k
11
votes
4
answers
2k
views
Literature for gauge field theory on the lattice in geometrical formulation
I have found an article by Huebschmann, Rudolph and Schmidt about "A Gauge Model for Quantum Mechanics on a Stratified Space" and I am very interested in this subject, but I don't have any ...
12
votes
3
answers
3k
views
Why do Physicists need unitary representation of Kac-Moody algebra?
My advisor mentioned to me that he talked to Witten last summer on representation theory, and Witten told him that unitary representations of Kac-Moody algebra are important to working physicists. But ...
- 5,515
28
votes
5
answers
7k
views
Particle Physics and Representations of Groups
This question is asked from a point of complete ignorance of physics and the standard model.
Every so often I hear that particles correspond to representations of certain Lie groups. For a person ...
- 5,929
12
votes
2
answers
2k
views
Derived Physics
Hello to all,
This question will probably be closed down as being off-topic faster than one can say "string theory", but here it goes: I've noticed that the problems I'm working on -the structure of ...
54
votes
6
answers
13k
views
Mathematical explanation of the failure to quantize gravity naively
One often hears in popular explanations of the failure to find a "Grand Unified Theory" that "Gravity goes off to infinity, but cutting off the edges gives us wrong answers", and other similar ...
20
votes
6
answers
3k
views
Perpetuum Mobile
In 2 hours after posting this, I realized that preserving Liouville measure solves the problem completely. Sorry for disturbing...
Construction of perpetuum mobile:
Consider room with mirror walls ...
14
votes
1
answer
7k
views
What is the meaning of symplectic structure? [closed]
Answers can come in mathematical, physical, and philosophical flavors.
Edit: There seems to be a consensus that this question is not formulated well. I must respectfully disagree. My interest in the ...
5
votes
2
answers
953
views
Singular K3 -- mathematical meaning?
There's a very interesting text by Cumrun Vafa called Geometric Physics.
Here I'm particularly interested in Chapter 4, where we take a Calabi-Yau manifold presented as a degenerating fibration:
...
- 15.1k
3
votes
2
answers
3k
views
Something like mathoverflow in other sciences [closed]
Are the sites similar to mathoverflow in other sciences related to mathematics? statistics, computer science, physics, economics, etc?
Let me explain what I mean by "similar": those are sites devoted ...
3
votes
1
answer
334
views
Prevalence of B-fields
I am wondering how B-fields, which are basic objects in Generalized Geometry, relate to the B-fields of Ben's question and the answers to it.
In Generalized Geometry, the B-field is a (1,1)-form, and ...
- 280
3
votes
0
answers
804
views
Children's drawings and Seiberg-Witten curves
This physics (bear with me for a while) paper seems to say something about Gal \bar Q/Q:
Children's Drawings From Seiberg-Witten Curves, hep-th/061108.
Let's ...
- 15.1k
10
votes
2
answers
1k
views
Cone shaped solutions to wave equation
When I studied physics, we learned how to write down planar waves and spherical waves. But, when I turn on my flashlight, I see a cone of light. How can I see that there is a solution to the wave ...
- 156k