Questions tagged [ads-cft]
AdS/CFT is a special case of the holographic principle. It states that a quantum gravitating theory in Anti-de-Sitter (AdS) space is exactly equivalent to the gauge theory/Conformal Field Theory (CFT) on its boundary.
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Can you always write entropy as integral over space?
I am mostly interested in the entanglement entropy of the ‘‘outside region’’ (aka ‘‘$S_\text{out}$’’) in the holographic entanglement entropy formulation in arXiv:1408.3203 and arXiv:1307.2892. Take ...
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Explanation of Multiplet Shortening and Unitary Bounds in Supersymmetry (AdS/CFT): Algebraic Insights
I am currently studying this paper and I'm struggling to grasp the concepts of multiplet shortening and unitary bounds in the context of supersymmetry. I am specifically interested in obtaining a ...
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Counting of zero-modes in conifold theory
I was reading Klebanov and Witten's paper on the conifold theory and at page 11 they state that
[...] In an instanton field of the first $U(N)$ with instanton number $k$, the gluinos of the first $U(...
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BPS States and Conditions: Definition and Significance in the Context of ADS/CFT
I am currently studying a paper similar to the one linked and I'm struggling to comprehend the concept of BPS (Bogomol'nyi-Prasad-Sommerfield) states/operators. The cited papers mention these terms ...
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AdS-CFT on a torus
A gauge theory at finite volume and temperature on a space like $S^{n-1}\times S^1$ is supposed to be dual to a string theory on either $AdS_{n+1}$ or a Schwarzschild black hole in $AdS_{n+1}$, with a ...
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What does it mean for a quantum field theory to "live" on a manifold?
I was attending lectures om holography where the lecturer kept on mentioning that a QFT lives on a Cauchy slice. What does that mean?
Is it such that each point of the slice is associated to a unique ...
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Getting confused with different metrics for AdS black hole
I'm getting confused with the convention for the metric that describes a (planar) AdS black hole in $1+d$ dimensions ($1$ timelike, $d$ spacelike).
The most common definition seems to be the one as in ...
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Hawking Temperature for a hairy BTZ Black Hole
The metric of a hairy Black Hole is given by:
$$ds^2 = \frac{L^2}{z^2}\biggl(-g(z) dt^2 + \frac{e^{2 A(z)}}{g(z)} dz^2 +d\varphi^2\biggr), $$
where $L$ is the AdS length taken to be $1$,$A(z)$ is the ...
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AdS, nearly AdS, and asymptotically AdS
Recently, I took a seminar about JT gravity, and the speaker said about exact Ads, nearly Ads, and asymptotically Ads.
I want to know the difference(i.e., the form of metric? or the conditions on ...
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Gluon scattering in AdS
In recent years there has been interest in computing scattering amplitudes of (super)gluons in Anti-de Sitter (AdS) space in all kinds of stringy theories in different spacetime dimensions (see for ...
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Dynkin labels of $psu(2,2|4)$
I'm currently studying the superconformal algebra $psu(2,2|4)$, but I'm having trouble understanding its representation.
Following arxiv:1012.4004
I know that the maximal compact subalgebra is su(2) $\...
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Gravitational backreaction in AdS/CFT
When we add a scalar field into AdS space time, under which limit can we ignore the gravitational back reaction? In the case of massless scalar, can we totally ignore the backreation to the background ...
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Naive questions on AdS/CFT dictionary and alternatives?
I'm starting to become curious about AdS/CFT since hearing that condensed matter theorists use it as a 'dictionary' to find gravity duals of things from condensed matter physics. How exactly does this ...
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Holographic self-energy for a scalar field in a slice of AdS
I am confused about a key step in Gherghetta's "TASI Lectures on a Holographic View of Beyond the Standard Model Physics" in the derivation of the holographic self-energy in the strongly ...
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Research progress in the symmetries of flat space holography
I was studying the papers
[$1$] Arjun Bagchi. The BMS/GCA correspondence
[$2$] Duval, C., Gibbons, G. W., & Horvathy, P. A. (2014). Conformal carroll groups. Journal of Physics A: Mathematical ...
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Jackiw-Teitelboim (JT) gravity as a matrix integral
I am reading https://arxiv.org/abs/1903.11115 by Saad, Shenker and Stanford. They relate an (averaged) $n$-point function in a random double-scaled matrix model to a path integral genus expansion in ...
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Quantum entanglement of the Sachdev-Ye-Kitaev models
I was following the paper https://journals.aps.org/prb/abstract/10.1103/PhysRevB.97.245126 on Quantum entanglement of the Sachdev-Ye-Kitaev models. As we know that this is a model of indistinguishable ...
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Why don't we have Poincare coordinate for de Sitter space unlike Anti de Sitter space?
My understanding is that you get de Sitter space from Anti de Sitter space, if you change $l^2$ to $-l^2$. However, why can't I find Poincare coordinate for de Sitter space, if Anti de Sitter space ...
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Derivatives as "dynamical variables of the theory"?
This question will probably sounds very broad.
So, I work with classical general relativity, a bit of field theory and semiclassical gravity. I have a friend, though, that works with things like ...
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In the context of the holographic principle, is the bulk-boundary correspondence due to entanglement?
According to the holographic principle, a "bulk" region of D dimensions corresponds to a "boundary" region of D-1 dimensions. In this context, the laws of physics of the bulk can ...
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Advanced string theory book recommendations [duplicate]
Let's say I fully understand Polchinski books on string theory
Are there any recommended and more advanced book on strings?
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Does the value of Maximum Lyapunov exponent depend on the eigenvalues of the system?
I am currently reading this paper where on page 8, the authors say that:
Negative eigenvalues correspond to unstable systems.
This correlates with Figure 8 on page 12.
Does it mean that there is a ...
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Pedagogical reference to learn how to work with CFTs?
I know very little about AdS/CFT, but I am considering looking more into quantum gravity for future research topics. From those of you who have already "conquered" AdS/CFT, I was wondering ...
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About the paper "Traversable wormhole dynamics on a quantum processor"
Recently a paper titled "Traversable wormhole dynamics on a quantum processor" was published in Nature.
From what I understand they are simulating these wormholes (dual of an $AdS_2$ ...
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In AdS/CFT, do we have Weyl-invariance or only conformal invariance?
The asymptotic symmetry group of $AdS_{d+1}$ is $SO(d,2)$, which just so happens to be the conformal group of $d$-dimensional Minkowski spacetime. Therefore the boundary dual, if it exists, has ...
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Can a saddle point corresponding to black hole horizon act as a source of chaos?
I was going through this paper where on page 5 they argue that in the given Poincare section:
Most of the orbits form regular tori, while we can also see that some tori near the saddle point of the ...
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Solving equations of motion with a background ansatz
Consider the effective 4d gravitational bulk action article, dual to $QFT_3$ on $\mathbb{R}^{2,1}$,
$ S_{QFT_3}=S_{CFT_3}+S_r +S_i=\frac{1}{2\kappa^2}\int dx^4\sqrt{-\gamma}(R+6-\frac{1}{2}(\nabla\phi)...
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What is the symmetry group of asymptotically AdS spacetime?
The isometry group of global $AdS_{d+1}$ is well-known to be $SO(d,2)$. I have a suspicion that when the spacetime is asymptotically AdS, with dynamical gravity in the bulk, the symmetry group gets ...
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How does AdS/CFT help us understand non-perturbative aspects of QCD?
I've heard AdS/CFT has found applications in many areas of physics where nonperturbative aspects leave us crippled in making any simple calculations.
Among these applications, I also have heard that ...
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Different limits of string theory parameters
So in (perturbative) String theory, it is my understanding that we have the following parameters (taking natural units).
The string length : $\ell_s$, which appears in front of the world-sheet action, ...
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AdS/CFT Statement
The following definition of the AdS/CFT correspondence is given in the Jerusalem Lectures on Black Holes and Quantum Information by Harlow:
Any relativistic conformal field theory on $\mathbb{R} \...
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Motivation of Holographic Exact Renormalisation Equation
I've recently been studying exact renormalisation alongside holographic renormalisation, and came across the following paper on the arXiv: https://arxiv.org/abs/hep-th/0001193.
I'm trying to ...
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How is every D-brane dual to 2 others?
For instance, A D3 brane is T dual to both a D2 and D4. I understand the idea that Type A and B theories are T dual to one another, but I don't understand how you get 2 different dual descriptions ...
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Specific Heat of SYK Model
For the SYK model, One can prove that for $N\to \infty$ the total energy can be written as the derivative of the imaginary time Green's function (see related question):
$$\langle H \rangle=\frac{N}{4} ...
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Bulk space of compactified Euclidean space other than the Euclidean AdS
In the standard AdS/CFT, the conformally compactified Euclidean space is the conformal boundary of the bulk Euclidean AdS space. Are there any other Einstein spaces (with different topology) that ...
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Vectors in AdS/CFT: scaling dimension and near boundary behaviour
I'm trying to understand how the near boundary expansion of a field in AdS$_{d+1}$ is related to the conformal dimension of the corresponding operator in the dual CFT$_d$.
I use coordinates in which ...
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AdS/CFT and entropy
I would like to calculate the entropy of a CFT on a circle, and I know the partition function of the disk. Can I use AdS/CFT:
$$ Z_{CFT} = Z_{\text{bulk}}$$
To deduce :
$$S_{CFT} = (1-\beta \partial_\...
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Group theory for advanced QFT
I have taken a course on group theory a few years ago. I have also used a little bit of group theory in a particle physics course.
However, now I have started with AdS/CFT and string theory and I am ...
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What does the discovery of pressure of black holes imply for spacetime thermodynamics?
As far as I know AdS/CFT and spacetime thermodynamics was motivated by the Bekenstein-Hawking Entropy formula of black holes.
Recently however it was discovered that black holes have a pressure as ...
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Operator insertions vs boundary conditions in AdS/CFT
This question is motivated by AdS/CFT, but really it's just about AdS quantum gravity. Consider quantum gravity in asymptotically AdS spacetime. For simplicity, assume there are no matter fields: the ...
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Relationship between mass and twist for operators with spin $s$ in the $AdS/CFT$ correspondence
The relation between scaling dimension and mass of a corresponding field in AdS is given by: $$\Delta=\frac{d}{2}+\sqrt{\frac{d^2}{4}+m^2R^2},$$
Is this formula only valid for scalar fields? I would ...
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Stress- energy tensor in AdS
I´m trying to reproduce some of the equations from the paper
-- A Stress Tensor For Anti-de Sitter Gravity, by Balasubramanian and Kraus,
https://arxiv.org/abs/hep-th/9902121 -- and I keep getting one ...
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AdS/CFT mapping of AdS background energy
I am sorry for what might be an elementary question as I am not an expert on AdS/CFT or CFT by any means.
I am currently studying the thermodynamics of a charged rotating black hole solution in odd ...
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How is the Virasoro symmetry realised on $AdS_3$?
In the context of the Holographic correspondence, $AdS_{n}/CFT_{n-1}$, it is often cited as a "confirmation" that the two symmetry groups of the theories correspond. Indeed, in dimensions $n&...
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Why are we able to compare the open and closed string perspective in AdS/CFT?
I am reading the book Gauge/Gravity Duality Foundations and Applications by M. Ammon and J. Erdmenger. In that book they state the relationship between parameters on both sides of the duality as
$$
g_{...
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BTZ black hole and thermal $AdS_3$
Why is Euclidean $BTZ$ black hole at temperature $T$, equivalent to thermal $AdS_3$ at temperature $1/T$?
I'm not really familiar with those objects, but I have used the modular transformation
$$\tau_{...
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What is the generally expected or more useful form of supersymmetry, on-shell or off-shell?
If the on-shell numbers of degrees of freedom of bosons and fermions match we
have on-shell supersymmetry, if the off-shell numbers match we have off-shell
supersymmetry. When LHC people say they are ...
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Is the Quantum Gravity mystery already solved by Susskind? [closed]
Very recently, Leonard Susskind presented a lecture presenting his proposal of Quantum Mechanics = Gravity (equality means duality).
Quantum Origins of Gravity
Is this really the end of Quantum ...
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Relation between the condensation gap and the critical temperature in superconductors/holographic superconductors
In some articles about holographic superconductors, it is written that when the condensation gap increases, the critical temperature decreases. For example, here: https://link.springer.com/article/10....
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Euclidean BTZ black hole dual to thermal CFT state
I'm studying $\textbf{Holographic Derivation of Entanglement Entropy from AdS/CFT}$ by Shinsei Ryu and Tadashi Takayanagi.
I'm trying to compute the entanglement entropy in $CFT_2/AdS_3$ at finite ...
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