Unanswered Questions
42,120 questions with no upvoted or accepted answers
115
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0
answers
6k
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Experimental test of the non-statisticality theorem?
Context: The paper On the reality of the quantum state (Nature Physics 8, 475–478 (2012) or arXiv:1111.3328) shows under suitable assumptions that the quantum state cannot be interpreted as a ...
84
votes
0
answers
3k
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Orbits of maximally entangled mixed states
It is well known (Please, see for example Geometry of quantum states by Bengtsson and Życzkowski ) that the set of $N$-dimensional density matrices is stratified by the adjoint action of $U(N)$, where ...
67
votes
1
answer
3k
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On the Coulomb branch of ${\cal N}=2$ supersymmetric gauge theory
The chiral ring of the Coulomb branch of a 4D ${\cal N}=2$ supersymmetric gauge theory is given by the Casimirs of the vector multiplet scalars, and they don't have non-trivial relations; the Casimirs ...
56
votes
0
answers
1k
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Systematic approach to deriving equations of collective field theory to any order
The collective field theory (see nLab for a list of main historical references) which came up as a generalization of the Bohm-Pines method in treating plasma oscillations are often used in the study ...
55
votes
1
answer
3k
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How to apply the Faddeev-Popov method to a simple integral
Some time ago I was reviewing my knowledge on QFT and I came across the question of Faddeev-Popov ghosts. At the time I was studying thеse matters, I used the book of Faddeev and Slavnov, but the ...
49
votes
0
answers
2k
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Can Lee-Yang zeros theorem account for triple point phase transition?
Now the prominent Lee-Yang theorem (or Physical Review 87, 410, 1952) has almost become a standard ingredient of any comprehensive statistical mechanics textbook.
If the volume tends to infinity, ...
45
votes
0
answers
2k
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$\operatorname{O}(N)$ sigma model at large $N$
I would like to better understand the main principles of large-$N$ expansion in quantum field theory. To this end I decided to consider simple toy-model with lagrangian (from Wikipedia)
$
\mathcal{L} ...
41
votes
0
answers
1k
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Positivity for the level of Chern-Simons theory
In many classical papers about Chern-Simons theory (see, e.g. [1]),
it is claimed that the Chern-Simons theories with gauge group $G$ are classified by an element of $k\in H^4(BG,\mathbb Z)$, the so-...
32
votes
0
answers
529
views
Is there any way to distinguish experimentally gauge mediation from gravity mediation in an unambiguous way?
There are lots of models of gravity mediated SUSY breaking with various spectra as well as various general gauge mediation models. Are there any "smoking gun" experimental singnatures that could ...
28
votes
0
answers
520
views
Minimal strings and topological strings
In http://arxiv.org/abs/hep-th/0206255 Dijkgraaf and Vafa showed that the closed string partition function of the topological B-model on a Calabi-Yau of the form $uv-H(x,y)=0$ coincides with the free ...
26
votes
4
answers
946
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Is there a physical interpretation to invariant random matrix ensembles?
Disclaimer. I am a graduate student in pure mathematics, so my knowledge of physics more advanced than basic 1st/2nd year undergraduate physics is very limited. I welcome corrections on any ...
26
votes
0
answers
616
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Extended Born relativity, Nambu 3-form and ternary ($n$-ary) symmetry
Background: Classical Mechanics is based on the Poincare-Cartan two-form
$$\omega_2=dx\wedge dp$$
where $p=\dot{x}$. Quantum mechanics is secretly a subtle modification of this. By the other hand, the ...
26
votes
0
answers
392
views
Quantum statistics of branes
Quantum statistics of particles (bosons, fermions, anyons) arises due to the possible topologies of curves in $D$-dimensional spacetime winding around each other
What happens if we replace particles ...
24
votes
0
answers
1k
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$p$-Adic String Theory and the String-orientation of Topological Modular Forms (tmf)
I am going to ask a question, at the end below, on whether anyone has tried to make more explicit what should be a close relation between p-adic string theory and the refinement of the superstring ...
24
votes
0
answers
391
views
Super Lie-infinity algebra of closed superstring field theory?
Bosonic closed string field theory is famously governed by a Lie n-algebra for $n = \infty$ whose $k$-ary bracket is given by the genus-0 (k+1)-point function in the BRST complex of the string.
One ...