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AdS/CFT Correspondence vs Verlinde Entropic Gravity

Emergent Spacetime & Gravity· within family

	AdS/CFT Correspondence Frontier	Verlinde Entropic Gravity Frontier
Proposed	1997 / 1998	2011 / 2017
Key figures	Juan Maldacena, Edward Witten, Steven Gubser, Igor Klebanov, Alexander Polyakov	Erik Verlinde
In one sentence	Juan Maldacena proposed in 1997 that gravity in anti-de Sitter (AdS) spacetime is exactly equivalent to a conformal field theory (CFT) defined on the AdS boundary. The conjecture is one of the most-cited papers in theoretical physics. Gubser, Klebanov, and Polyakov 1998 and Witten 1998 made the duality computationally precise: every gravitational quantity in the bulk has a specific CFT dual on the boundary. The framework turned the abstract holographic principle into a working calculational machine and remains the central technical engine of the broader emergent-spacetime program.	Verlinde proposed that gravity is not a fundamental force but an entropic effect arising from changes in information on holographic screens. The 2016 extension to dark matter has been substantially constrained by 2017-2019 weak-lensing and radial-acceleration-relation tests.
Predictions	Gravity in anti-de Sitter spacetime is exactly equivalent to a conformal field theory on the boundary; every gravitational quantity has a CFT dual Black hole [[entropy]] in AdS equals the entropy of the dual thermal CFT state, providing a microscopic count of the gravitational degrees of freedom Strongly-coupled gauge theories can be analyzed via their weakly-coupled gravitational duals; this is the technical engine for holographic-QCD and AdS/CMT calculations The bulk gravitational reconstruction from boundary data has specific encoding properties (entanglement-wedge reconstruction, modular flows) that are computable in the CFT	2010 framework: Newton's law of gravity recovered as an entropic force on holographic screens; relativistic generalization should match GR at leading order 2016 dark-matter extension: a specific scale-dependent extra gravitational potential producing MOND-like behavior in galaxies, without dark-matter particles Specific baryonic Tully-Fisher-like relations between baryonic mass and apparent dark mass; deviations from the predicted scaling falsify the dark-matter extension
Where it breaks	The correspondence is most precise in anti-de Sitter space, which has negative cosmological constant; our universe has positive cosmological constant (de Sitter), and the extension to de Sitter holography remains a 25-year open problem Mathematical rigor is established in the large-N planar limit; corrections away from this limit (1/N expansions, stringy corrections) are calculable but introduce additional structure Different gauge-theory duals are needed for different bulk geometries; there is no single 'master' AdS/CFT correspondence that applies universally Whether the duality is a fundamental property of physical reality or a deep mathematical coincidence in certain backgrounds is debated; most working physicists treat it as physical, but the philosophical status remains live	Lelli, McGaugh & Schombert (2017) tested the 2016 prediction against the radial acceleration relation across ~150 SPARC-database galaxies and found inconsistencies with the predicted scaling at low accelerations Tamosiunas et al. (2019) tested the prediction at galaxy-cluster scales and found significant tension with observed lensing profiles The original 2010 entropic derivation has been criticized for assuming too much input (Bekenstein-Hawking entropy-area law, Unruh temperature) to legitimately derive Newton's gravity from first principles The microscopic model of underlying degrees of freedom remains vague; critics see the framework as under-specified compared to explicit dark-matter models No fully relativistic, calculable version of the 2016 dark-matter scheme exists; observational analyses use phenomenological approximations
Key unresolved problem	The wrong-sign problem: the one exact gravity-equals-boundary-physics dictionary we have only works when the cosmological constant is negative, the opposite sign to the positive value measured in our real, accelerating universe.	The cluster mismatch: the 2016 version that tries to do away with dark matter predicts how galaxy clusters should bend light, but those predictions miss the real measurements by a wide margin, and no fully worked-out relativistic version exists to fix it.
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AdS/CFT Correspondence

1997 / 1998 · Frontier

Verlinde Entropic Gravity

2011 / 2017 · Frontier

Proposed

1997 / 1998

2011 / 2017

Key figures

Juan Maldacena, Edward Witten, Steven Gubser, Igor Klebanov, Alexander Polyakov

Erik Verlinde

In one sentence

Juan Maldacena proposed in 1997 that gravity in anti-de Sitter (AdS) spacetime is exactly equivalent to a conformal field theory (CFT) defined on the AdS boundary. The conjecture is one of the most-cited papers in theoretical physics. Gubser, Klebanov, and Polyakov 1998 and Witten 1998 made the duality computationally precise: every gravitational quantity in the bulk has a specific CFT dual on the boundary. The framework turned the abstract holographic principle into a working calculational machine and remains the central technical engine of the broader emergent-spacetime program.

Verlinde proposed that gravity is not a fundamental force but an entropic effect arising from changes in information on holographic screens. The 2016 extension to dark matter has been substantially constrained by 2017-2019 weak-lensing and radial-acceleration-relation tests.

Predictions

Gravity in anti-de Sitter spacetime is exactly equivalent to a conformal field theory on the boundary; every gravitational quantity has a CFT dual
Black hole [[entropy]] in AdS equals the entropy of the dual thermal CFT state, providing a microscopic count of the gravitational degrees of freedom
Strongly-coupled gauge theories can be analyzed via their weakly-coupled gravitational duals; this is the technical engine for holographic-QCD and AdS/CMT calculations
The bulk gravitational reconstruction from boundary data has specific encoding properties (entanglement-wedge reconstruction, modular flows) that are computable in the CFT

2010 framework: Newton's law of gravity recovered as an entropic force on holographic screens; relativistic generalization should match GR at leading order
2016 dark-matter extension: a specific scale-dependent extra gravitational potential producing MOND-like behavior in galaxies, without dark-matter particles
Specific baryonic Tully-Fisher-like relations between baryonic mass and apparent dark mass; deviations from the predicted scaling falsify the dark-matter extension

Where it breaks

The correspondence is most precise in anti-de Sitter space, which has negative cosmological constant; our universe has positive cosmological constant (de Sitter), and the extension to de Sitter holography remains a 25-year open problem
Mathematical rigor is established in the large-N planar limit; corrections away from this limit (1/N expansions, stringy corrections) are calculable but introduce additional structure
Different gauge-theory duals are needed for different bulk geometries; there is no single 'master' AdS/CFT correspondence that applies universally
Whether the duality is a fundamental property of physical reality or a deep mathematical coincidence in certain backgrounds is debated; most working physicists treat it as physical, but the philosophical status remains live

Lelli, McGaugh & Schombert (2017) tested the 2016 prediction against the radial acceleration relation across ~150 SPARC-database galaxies and found inconsistencies with the predicted scaling at low accelerations
Tamosiunas et al. (2019) tested the prediction at galaxy-cluster scales and found significant tension with observed lensing profiles
The original 2010 entropic derivation has been criticized for assuming too much input (Bekenstein-Hawking entropy-area law, Unruh temperature) to legitimately derive Newton's gravity from first principles
The microscopic model of underlying degrees of freedom remains vague; critics see the framework as under-specified compared to explicit dark-matter models
No fully relativistic, calculable version of the 2016 dark-matter scheme exists; observational analyses use phenomenological approximations

Key unresolved problem

The wrong-sign problem: the one exact gravity-equals-boundary-physics dictionary we have only works when the cosmological constant is negative, the opposite sign to the positive value measured in our real, accelerating universe.

The cluster mismatch: the 2016 version that tries to do away with dark matter predicts how galaxy clusters should bend light, but those predictions miss the real measurements by a wide margin, and no fully worked-out relativistic version exists to fix it.

Reader vote

No votes yet