Questions tagged [string-theory]
For questions about string theory, which is a research framework in theoretical physics and mathematical physics that attempts to unify quantum theories and general relativity.
98 questions
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How to understand the twists physicists use in topological string theory?
I have a very hard time to understand something physicists call $A$ or $B$ twists in the context of topological string theory. A canonical reference seems to be this Witten's paper.
Let $\Sigma$ be a ...
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What are the the A-Side and B-Side in symplectic geometry / algebraic geometry / string theory? [closed]
"The A-Side" and "the B-Side" are terms that I've heard thrown around in some talks on symplectic geometry and algebraic geometry with a string theory flavor, but I can't seem to ...
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Solution to wave equation on a cylinder
In many texts, it is claimed that the most general solution to the wave equation
$$(\partial_{\tau}^2-\partial^{2}_{\sigma} )X(\sigma,\tau) = 0$$
where $(\sigma,\tau) \in S^1 \times \mathbb{R}$ is as ...
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Integral over variable and its complex conjugate
What I was trying to solve was an integral, where the integration variable are a complex numer $z$ and its complex conjugate $\bar{z}$. In particular the integrals are the following
\begin{equation}
\...
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Is the new series for 𝜋 a Big (or even Medium) Deal?
There's been some oohing and ahhing in the science press recently over the discovery of a new formula for $\pi$ obtained as a side effect of computing amplitudes in string theory:
$$\pi=4+\sum_{n=1}^\...
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For which integers $m$ does an infinite string of characters $S = c_{1} \cdot c_{2} \cdot c_{3} \cdot c_{4} \cdot c_{5} \ldots$ exist
Question:
For which integers $m$ does an infinite string of characters
$$S = c_{1} \cdot c_{2} \cdot c_{3} \cdot c_{4} \cdot c_{5} \ldots$$
exist such that for all $n \in \mathbb{Z}_{>0}$ there are ...
- 8,216
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Kahler geometry and topology in modern physics
How are tools and concepts Complex and algebraic geometry (and also algebraic topology) used in modern physics, such as in string theory? Is there any introductory text which deals with this topic (ie ...
- 434
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Is my logic correct? A bit string of n with more 0s than 1s
I am learning about combinatorial and bit strings.
I decided to use combinatorial reasoning and wanted to see if my logic made sense.
The question: How many bit strings of length n contain more 0’s ...
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What is the variance of the number of occurrences of a subsequence in a random sequence.
Let $N_n$ be a random string of length $n$, where each of the $n$ characters in $S_n$ is independently chosen with uniform probability from the set $\mathcal{S} := \{s_1, \ldots, s_K\}$. Here $K$ is ...
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Confusing definitions of Modular Group and Teichmüller space
Notations
1.$\Sigma_g$ is the Reimann surface with genus $g$
2.$M_g$ is the space of all metrics
3.Diff($\Sigma_g$) is the diffeomorphism on $\Sigma_g$
4.$\text{Diff}_0(\Sigma)$ is the connected ...
- 131
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What was the difficulty in enumerative geometry problems before physics?
I have read the book 'Enumerative Geometry and String Theory' by Katz, and it left me with some questions. It is outlined in the text how ideas from String theory and TQFT has enriched enumerative ...
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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}\...
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Proving that $L_{-1}v=0$ implies $v\in V_0$ in a vertex operator algebra
The discussion of the actual problem is labelled in bold after the notoriously long definition of vertex operator algebra is given for the sake of completeness (Note: "fields" and "...
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The connectivity of reflexive polytopes from just their vertices?
I'm working with the Kreuzer-Skarke database of 4-dimensional reflexive polyhedra. It lists almost half a billion polytopes, each represented by its vertex list and a few properties (Hodge numbers and ...
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Bijection between composition algebras over R and classical superstring theories
In the page for superstring theory, Wikipedia states:
Another approach to the number of superstring theories refers to the mathematical structure called composition algebra. In the findings of ...
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