All Questions
Tagged with string-theory mathematical-physics
114 questions
1
vote
0
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92
views
Free-Field Construction of the Virasoro Algebra
The Virasoro algebra is given by the relation
$$
[L_m, L_n] = (m-n)L_{m+n} + \frac{c}{12}m(m^2 -1)\delta_{m,-n}.
$$
Also consider a free spin-1 field in 1+1 dimensions (which is invariant under ...
- 3,157
1
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0
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65
views
Reference on the quantization of Polyakov action at higher genus
Despite my searches, I was unable to find a good reference on this topic. I was looking for a reference about quantization of the Polyakov action for an arbitrary Riemann surface. I am thankful to ...
3
votes
0
answers
129
views
Mathematical objects on crystal meltings and their relation to particle physics
I am a mathematician interested in analytic number theory, and I found the paper Dimers and Amoebae
, which shows how many mathematical objects like the Mahler measure, the Ronkin function and the ...
- 155
1
vote
1
answer
57
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Divergence of gauge kinetic coupling at the AdS boundary
This is the Einstein-Maxwell-Dilaton Gravity action:
\begin{eqnarray*}
S_{EM} = -\frac{1}{16 \pi G_5} \int \mathrm{d^5}x \sqrt{-g} \ [R - \frac{f(\phi)}{4}F_{MN}F^{MN} -\frac{1}{2}D_{M}\phi D^{M}\...
- 203
6
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2
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729
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Compactification in String Theory and Compactification in Topology are they the same thing?
In topology, there is a concept of compactification which is defined as follows.
A space $Z$ is a compactification of $X$ if $Z$ is compact Hausdorff and there exists an
embedding $j:X \rightarrow Z $ ...
- 368
7
votes
2
answers
949
views
In what sense is string theory not expected to be a QFT?
This question came to mind while reading about Weinberg's folk theorem that any quantum theory that is Poincare covariant and satisfies cluster decomposition will look like a quantum field theory at ...
- 1,185
4
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0
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118
views
Moduli space for Riemann surfaces with boundaries and open string loop diagrams
I'm searching for information on the moduli space for Riemann surfaces with boundaries, like the ones used to compute open string loop diagrams. I found a huge lot of info for the case without ...
- 1,196
5
votes
1
answer
266
views
In what sense does a pure spinor represent the orientation of a unique spacelike codimension-2 plane?
References 1 and 2 define a pure spinor $\psi$ to be a solution of the Cartan-Penrose equation
$$
\newcommand{\opsi}{{\overline\psi}}
v^\mu\gamma_\mu\psi=0
\hspace{1cm}
\text{with}
\hspace{1cm}
v^\mu\...
- 55.5k
2
votes
1
answer
333
views
Spin structures and boundary conditions for worldsheet fermions
The definition I'm aware of a spin structure is the following one:
Definition: Let $(M,g)$ be a semi-Riemannian manifold with signature $(p,q)$. Let ${\cal F}M$ be the principal ${\rm SO}(p,q)$-...
- 37.9k
6
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1
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358
views
Why do we consider the Witt algebra to be the symmetry algebra of a classical conformal field theory?
In standard physics textbooks, it is usually stated that the Witt algebra is the symmetry algebra of classical conformal field theories in two dimensions.
Following M. Schottenloher, A Mathematical ...
1
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2
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370
views
Quiver Mechanics
What do you suggest as an essential and introductory set of references in Physics literature for learning quivers? Any textbook?
3
votes
1
answer
160
views
Michio Kaku: General relativity action is not bounded from below (?)
In p.9 of Michio Kaku book Introduction to Superstrings and M-Theory-Springer (1998), he said
General relativity (GR) is also plagued with similar difficulties. The GR action is not bounded from ...
- 4,416
1
vote
0
answers
130
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Physical origin of coisotropic branes
The paper "Remarks on A-branes, Mirror Symmetry, and the Fukaya category" develops the possibility of A-model open strings ending on a coisotropic submanifold equipped with a holomorphic ...
- 3,932
3
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0
answers
106
views
Mass deformations in D-brane systems
It is well known that the worldvolume theory of $N$ coincident D$p$-branes is given by the $U(N)$ Yang-Mills theory in $(p+1)$-dimensions. One important feature of this setup is the possibility of ...
- 3,932
1
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1
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249
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Is Weyl transformation part of diffeomorphism? Does a gravitational anomaly capture also the anomaly due to Weyl transformation? [duplicate]
Weyl transformation is a local rescaling of the metric tensor
$$
g_{ab}\rightarrow e^{-2\omega(x)}g_{ab}
$$
Diffeomorphism maps to a theory under arbitrary differentiable coordinate transformations
(...
- 4,416