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.
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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 ...
4
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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 ...
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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 ...
Steven Chang
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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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path integral of scalar field action on Riemann surface with boundary
In their paper 'Sewing Polyakov Amplitudes I: Sewing at a Fixed Conformal Structure' Carlip et al. start by considering the path integral $$Z_{\Sigma'}[\tilde{X}] = \int [dX]e^{-S[X]} $$ for the ...
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Section of the projection map [closed]
I have a CY four-fold as a hypersurface of degree $(4,3)$ in $P^3\times P^2$ and I have the projection map from this hypersurface say $X$ to $P^3$ as $\pi:X \rightarrow P^3$. Does this admit a section?...
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Compactification in String Theory [closed]
It seems to me that the idea of compactification in String theory is related to the concepts of Compactification and Quotient topology in topology theory. How compactification in String theory can be ...
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What does $Y(1,z)$ = id for vertex algebras mean?
I'm adding an update to this post here with my current understanding of the situation for context. I read some Wikipedia articles and two texts. I am having some trouble so I figure I would attempt to ...
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