The Holographic principle is a principle that states that the information within a region is exactly described by that on its boundary.

learn more… | top users | synonyms

0
votes
0answers
39 views

Has anyone explored a possible duality between quantum gravity and statistical mechanics?

There is a well known duality between quantum mechanics in D dimensions and classical statistical mechanics in D+1 dimensions. Specifically, the Euclidean version of the path integral in D dimensions ...
0
votes
0answers
25 views

Do December 2015 Fermilab Holometer experiment results suggest space-time not discretely emergent?

I read the December 2015 paper Search for Space-Time Correlations from the Planck Scale with the Fermilab Holometer available here and looked at the various related posts here at PSE. It seems to me ...
1
vote
0answers
25 views

what is the metric of N-sheeted $AdS_3$?

Suppose the AdS$_3$ metric is given by $$ ds^2 =d\rho^2+cosh^2\rho d\psi^2 +sinh^2 \rho d\phi^2 $$ what is the n-sheeted space of it? Can the n-sheeted BTZ be constructed from it by identifications ...
5
votes
1answer
140 views

What is the physics behind “Bulk-edge correspondence”?

There is a frequently mentioned concept in the field of topological insulator called "bulk-edge correspondence" or "bulk-boundary correspondence", which basically gives the relationship between the ...
3
votes
1answer
35 views

About the holographic principle

I read at a book this quote "As the degrees of freedom of a particle are the product of all the degrees of freedom of its sub-particles, were a particle to have infinite subdivisions into ...
0
votes
0answers
21 views

Action and equation of motion for codim-2 “cosmic” brane in Einstein gravity, in 3d

Consider the following action, $$ S = S_{EH} + S_{B} = -\frac{1}{8\pi G_N}\int d^3 X \sqrt{G}R + T \int dy \sqrt{g} , $$ where, $G_{\mu \nu}$ is the bulk metric, and $g$ is the induced metric on the ...
3
votes
0answers
48 views

Reference request: QFT and AdS/CFT for information theorists

There is a lot of buzz recently about connections between quantum information theory and quantum field theory/string theory. I would like to understand in particular how quantum information methods ...
0
votes
0answers
31 views

What is an hologram, and why is it relevant to physics?

What is an hologram, and why is it relevant to physics? I've seen this term appear in various vulgarization books. Is there an intuitive way to understand it? Is it related to the holographic ...
1
vote
0answers
35 views

What is an extremal horizon?

In the contest of holography and thermodynamics, what is an extremal horizon? I am going through a paper by Hartnoll, Santos - Disordered Horizons: Holography of randomly disordered fixed points. They ...
3
votes
1answer
90 views

On the c-theorem

I have been reading a few papers on CFT and AdS/CFT regarding the c-theorem and I have a few questions regarding c-theorems: a) Why is it that the c-theorem is usually considered for only unitary ...
1
vote
1answer
71 views

“Dictionary” between QFTs in D and D-1 dimensions?

Consider the Einstein field equations. Suppose, for instance, that the RHS, the stress-energy tensor, is uniquely determined by the electromagnetic field. Now, if we imagine a quantized version of ...
0
votes
0answers
69 views

What is a Witten diagram?

Recently I heard the terminology of Witten diagram. Studying QFT, I frequently see Feynman diagrams and use them to compute scattering amplitudes, one-loop corrections and so on. In string theory ...
0
votes
0answers
46 views

Can a massive imploding sphere smash the holographic principle and conservation of information into oblivion?

Let $\text{BH}_1$ be a black hole of mass $M_1$, zero charge and angular momentum, and event horizon radius $R_1=\frac{2GM_1}{c^2}$. Alice is loitering at distance (all distances here are from the ...
2
votes
0answers
22 views
3
votes
1answer
41 views

In the Holometer experiment, why would one of the split laser beams arriving back at a slightly different time indicate the universe was quantized?

All the pop-sci articles I've read have a description of the set-up similar to this: It uses a pair of laser interferometers placed close to one another, each sending a one-kilowatt beam of light ...
3
votes
2answers
91 views

AdS/CFT Group Theory

I have a two part question about AdS/CFT: Is the only necessary ingredient that the isometry group of AdS matches the conformal group in one dimension less or are there other prerequisites to build ...
1
vote
1answer
80 views

Holographic universe experiment?

I heard a passing news story which a satellite employed to prove or disprove the Holographic Universe theory came back disproving the Holographic Universe Theory. I searched for recent news reports ...
4
votes
0answers
1k views

holographic principle and Wheeler's bag of gold

How is it possible to explain "bag of gold" spacetimes (see Marlof) such that the ideas are compatible with AdS/CFT and the holographic principle?
4
votes
0answers
45 views

Brane interactions?

In particle physics, in QFT's, interactions come from the interaction piece in the Lagrangian (action). In string theory, waiting for a complete formulation of SFT, we have to add "by hand" ...
1
vote
1answer
51 views

Bekenstein bound and an infinite universe

I have a question about the Bekenstein bound or the holographic principle. I make the following assumptions: The universe is infinite The universe is homogeneous These assumptions are at least ...
5
votes
1answer
197 views

Charged CFT observables and AdS/CFT

I have a simple question regarding the holographic dictionary when mapping operators on the CFT side to those in AdS. One piece of the dictionary is that a global symmetry maps onto a gauge symmetry ...
0
votes
1answer
58 views

Entangled systems and heat

Suppose I have two extended bodies that are entangled to each other. Are the thermal properties of the objects affected in some way by entanglement? For example, Imagine that one of the entangled ...
8
votes
0answers
982 views

Why is the AdS/CFT approach to superconductors rarely cited in condensed matter publications?

Let me put things into perspective by comparing with other applications of string theory. Nowadays review papers written by cosmologists about inflation models often discuss string theory scenarios ...
1
vote
0answers
28 views

Holographic dualities with a QFT with a mass gap

The original holographic duality AdS/CFT points to a conformal field theory in the boundary. CFTs do not have a mass gap and all mass spectra are allowed Are there any existing examples of ...
2
votes
0answers
32 views

Light Sheets and the Holographic Entropy Bound

I'm trying to understand light sheets as related to the holographic entropy bound for information. This bound equates the information on a surface (e.g. the event horizon of a black hole) with the ...
1
vote
1answer
233 views

Whether the holographic universe of string theory prove the hypothesis of the holographic universe created by David Bohm or not?

Bohm, David (1980), Wholeness and the Implicate Order, London: Routledge, ISBN 0-7100-0971-2 As we can see from the book above, David created the hypothesis of the holopraphic universe in 1980. And ...
2
votes
1answer
125 views

What are “local degrees of freedom in gravity”, and why do they lead to fixed energy densities?

I am reading Jan de Boer's review of the AdS/CFT correspondence and I quote from end of page 1, where he is talking about equivalence of $(d+1)$-dimensional gravity to $d$-dimensional field theory ...
4
votes
2answers
2k views

What are the implications of the Holographic principle?

What are the implications for the Holographic principle? I understand the basics of the principle, the relationship with black holes and string theory but what this is going to tell us? Does it help ...
9
votes
3answers
2k views

Information encoded on the surface of a black hole

If an object that enters a black hole has its information content frozen at the event horizon, in what sense is it frozen? The usual analogy is of a hologram encoded in 2d which can be decoded into a ...
0
votes
0answers
29 views

What is the meaning of conformal mass on a branched manifold?

Consider the following QFT on the "branched" manifold, $\mathbb{H}^2 \times S^1_q$ where $S^1_q$ is an unit radius circle whose angular coordinate goes from $0$ to $2\pi q$, and hence the "branching". ...
1
vote
0answers
31 views

Standard references in (holographic) entanglement entropy literature (Part 2)

This is a continuation of this previously unanswered question, Standard references in (holographic) entanglement entropy literature (Part 1) I am wondering as to what are the standard references that ...
3
votes
0answers
68 views

Standard references in (holographic) entanglement entropy literature (Part 1)

While writing a paper, I am wondering as to what are the standard references that one refers to for these various facts about entanglement entropy. I want to know as to what are the papers one should ...
1
vote
1answer
60 views

How does the holographic principle apply to the $n$ dimensional space of String Theory?

The holographic principle is a property of string theories and a supposed property of quantum gravity that states that the description of a volume of space can be thought of as encoded on a ...
0
votes
0answers
90 views

Is the Wheeler deWitt equation consistent with the holographic principle?

In this paper by Sean Carroll (What if Time Really Exists), there's a section "Lessons from Duality" where he says that the holographic principle (and in particular, that a lower dimensional ...
0
votes
0answers
81 views

About Fermilab's holographic experiment

I read this article. I am no professional, and certain statements left me wondering. They say: “We are specifically trying to determine if there is a limit to the precision with which we can ...
1
vote
0answers
52 views

Holographic dual of pure-classical systems

There are classical systems (eg. see Sections VII and VIII of Kogut's review) that shares many of the properties of a pure-gauge SU(N) quantum theory including factorization and mass-gap, but with ...
2
votes
2answers
87 views

Maximum density that we can store information

I was informed that: There is a maximum density at which we can store information. For a sphere with surface area A, the maximum information that can be contained within is equivalent to the ...
0
votes
1answer
148 views

Any interesting implications of a holographic black hole in a holographic universe?

Bear with me; I don't have a background in physics, nor am I sure I even understand the things I'm talking about. I recently read that math/physics for a holographic black hole could be applied to ...
2
votes
1answer
93 views

Holographic dual of a massive QFT?

A naive question about holographic dual of a massive QFT: The Ryu-Takanayagi formula for the entanglement entropy (see their paper) seem to suggest that the holographic dual of a massive QFT (e.g. a ...
0
votes
0answers
72 views

How does a hologram record the incident laser?

How does the hologram (the photographic plate) record the incident laser beams when they hit onto it, what happens inside the hologram so that it records these laser beams?
5
votes
3answers
201 views

What happens at the center of a black hole according to holographic theory?

As far as I understand, the AdS/CFT correspondence proposed by Maldacena is an exact duality to a four-dimensional theory, which interpolates between one well-defined conformal field theory in the UV ...
13
votes
1answer
807 views

How many bits are encoded on the surface of the smallest black hole?

Here's my guess ($157\, \textrm{bits}$) and how I got there. Please feel free to disregard completely and give your own answer. My understanding (please correct any wrong assumptions as there may be ...
0
votes
0answers
46 views

Does the holographic principle for black holes mean that information is cloned?

When an object falls into a black hole, does the holographic principle say that the information is copied and stored on the event horizon while the original information falls in?
0
votes
0answers
55 views

Entropy of the boundary and stress-energy tensor in the bulk

The importance of this result cannot be understated: Positivity, monotonicity and convexity of relative entropy in the boundary is implied by the positivity of the stress-energy density tensor in the ...
6
votes
1answer
259 views

Why holographic renormalization?

Why is there a need to perform holographic renormalization for the normal $AdS_5\times S^5$/CFT$_4$ correspondence if the brane theory is conformal? Since the flow along the AdS direction $r$ is ...
0
votes
3answers
226 views

why does string theory require holography?

string theory solve the high energy gravity problem by making it mushier: Warped Passages - 14 - String Theory’s Origins Strings—unlike quarks—have no hard scattering processes. They have ...
1
vote
1answer
90 views

Singleton representations of $SO(2, d)$?

What is meant by "singleton" representations of $SO(2, d)$ and 'small representations' in Witten's paper, Anti de Sitter Space and Holography?
2
votes
3answers
483 views

Is the difference between an event horizon and a singularity merely perspective?

I know the question has been asked about how an event horizon is distinguishable from a singularity given that time must come to a stop at the event horizon, but I haven't been fully satisfied by the ...
0
votes
1answer
197 views

Why is the universe 3D if the holographic principle says it's encoded in a its surface?

The way I understand the holographic principle is that everything in a 3D space can be thought of as living on the 2D boundary of that space. If that is the case, why does everything in the universe ...
10
votes
2answers
148 views

Is quantum uncertainty a function of how matter is distributed in the universe?

As an outcome of his PhD thesis work, Richard Feynman and John Wheeler wrote a series of papers on how the kickback on an electron as it emits a photon can be modeled accurately as the result of an ...