AdS/CFT, turbulence and chaos
Lead Research Organisation:
Queen Mary University of London
Department Name: Physics
Abstract
Our current understanding of Nature is centered around two theories: general relativity which describes gravity, and quantum field theory which describes the strong and electroweak interactions and various low-energy phenomena. Naive attempts to unify these two theories lead to insurmountable difficulties. Moreover, a unified theory would ideally explain recent cosmological observations such as the acceleration of the universe, dark matter and cosmic inflation. This presents challenges to our understanding that must be addressed by new ideas.
As of today, the best candidate framework for unification is string theory which proposes that matter is not made of point particles, but one-dimensional strings. Although the theory solves the problem of combining gravity with the particle physics, the best understood solutions are ten dimensional. The extra six dimensions may be compactified which presents new challenges.
In the 1990s it has become clear that string theory also contains higher-dimensional objects called ``branes''. Furthermore, different types of string theory arise as limits of a unique theory: M-theory. It is known that in M-theory branes, and not strings, are the fundamental objects. However, a microscopic description of eleven-dimensional M-theory is still missing.
The Centre for Research in String Theory (CRST) at Queen Mary University of London has been at the forefront of research in string theory and quantum field theory. My STFC-funded research at CRST will be focused on the study of string theory. I will investigate two-dimensional toy models in order to unravel the mysteries of black holes in the context of quantum gravity.
Another research direction will be the study of extended objects (strings and branes) with the tools that I have recently developed. Understanding the quantum behavior of branes will be essential for understanding M-theory.
By perturbing strings, one can produce a very interesting phenomenon called wave-turbulence. In many respects, this phenomenon is similar to the fascinating (but more complicated) turbulence that can be observed in real-life fluids with unstable interacting vortices appearing on many scales. I will investigate wave-turbulence and develop analytical tools for describing the system.
As of today, the best candidate framework for unification is string theory which proposes that matter is not made of point particles, but one-dimensional strings. Although the theory solves the problem of combining gravity with the particle physics, the best understood solutions are ten dimensional. The extra six dimensions may be compactified which presents new challenges.
In the 1990s it has become clear that string theory also contains higher-dimensional objects called ``branes''. Furthermore, different types of string theory arise as limits of a unique theory: M-theory. It is known that in M-theory branes, and not strings, are the fundamental objects. However, a microscopic description of eleven-dimensional M-theory is still missing.
The Centre for Research in String Theory (CRST) at Queen Mary University of London has been at the forefront of research in string theory and quantum field theory. My STFC-funded research at CRST will be focused on the study of string theory. I will investigate two-dimensional toy models in order to unravel the mysteries of black holes in the context of quantum gravity.
Another research direction will be the study of extended objects (strings and branes) with the tools that I have recently developed. Understanding the quantum behavior of branes will be essential for understanding M-theory.
By perturbing strings, one can produce a very interesting phenomenon called wave-turbulence. In many respects, this phenomenon is similar to the fascinating (but more complicated) turbulence that can be observed in real-life fluids with unstable interacting vortices appearing on many scales. I will investigate wave-turbulence and develop analytical tools for describing the system.
Organisations
- Queen Mary University of London (Lead Research Organisation)
- University of Cambridge (Collaboration)
- Uppsala University (Collaboration)
- Massachusetts Institute of Technology (Collaboration)
- Imperial College London (Collaboration)
- UNIVERSITY COLLEGE LONDON (Collaboration)
- KING'S COLLEGE LONDON (Collaboration)
- University of Amsterdam (Collaboration)
People |
ORCID iD |
| David Vegh (Principal Investigator / Fellow) |
Publications
Blake M
(2020)
Horizon constraints on holographic Green's functions
in Journal of High Energy Physics
Ceplak N
(2020)
Fermionic pole-skipping in holography
in Journal of High Energy Physics
Ceplak N
(2021)
Pole skipping and Rarita-Schwinger fields
in Physical Review D
Chapman S
(2023)
Complex geodesics in de Sitter space
in Journal of High Energy Physics
David Vegh
(2021)
Relativistic membrane solutions in AdS4
in arxiv.org
David Vegh
(2023)
The 't Hooft equation as a quantum spectral curve
in arxiv.org
De Boer J
(2018)
Chaotic Strings in AdS/CFT.
in Physical review letters
Sword L
(2022)
Kasner geometries inside holographic superconductors
in Journal of High Energy Physics
Sword L
(2022)
What lies beyond the horizon of a holographic p-wave superconductor
in Journal of High Energy Physics
Sword L
(2024)
Quantum mechanical bootstrap on the interval: Obtaining the exact spectrum
in Physical Review D
| Description | During the tenure of this grant, we made several significant discoveries in the areas of string theory, black holes, and quantum field theory: 1. Turbulence in Strings and Curved Space: We observed a phenomenon known as "wave turbulence" on a string moving in curved space. This is somewhat similar to the chaotic turbulence seen in real-life fluids, such as swirling patterns in smoke or ocean waves. Identifying its properties helps us understand how energy spreads in fundamental physical systems. 2. New Insights into Quantum Field Theories: We uncovered general properties of quantum field theories by studying their response functions-which describe how a system reacts to small disturbances. The systems we explored are "holographic", meaning they can also be described using a higher-dimensional gravitational theory (via the AdS/CFT correspondence). These findings enhance our understanding of strongly interacting quantum systems, which appear in both high-energy physics and condensed matter physics. 3. Discretising Strings in a Consistent Way: A key challenge in string theory is understanding its fundamental mathematical structure. We developed a new way to discretise the smooth string, preserving essential features of the original theory. This approach provides valuable insights into "quantum spectral curves", a powerful tool used to study the AdS/CFT correspondence-a major framework connecting gravity and quantum mechanics. 4. Instabilities Behind Black Hole Horizons: We investigated Einstein's field equations, which describe how spacetime curves under gravity, and found that they become unstable behind black hole horizons. This means that, under certain conditions, the fabric of spacetime itself starts oscillating in unexpected ways. By studying these new oscillating geometries, we gain a deeper understanding of what happens inside black holes and the fundamental nature of spacetime. |
| Exploitation Route | The outcomes of this research provide new insights and tools that can be further developed and applied in several ways across theoretical physics, mathematics, and potentially other disciplines. |
| Sectors | Other |
| Description | Amplitudes, Strings and Duality |
| Amount | £890,210 (GBP) |
| Funding ID | ST/T000686/1 |
| Organisation | Science and Technologies Facilities Council (STFC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 09/2020 |
| End | 09/2024 |
| Description | String Theory, Gauge Theory and Duality |
| Amount | £710,337 (GBP) |
| Funding ID | ST/P000754/1 |
| Organisation | Science and Technologies Facilities Council (STFC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 09/2017 |
| End | 09/2021 |
| Description | Amsterdam collaboration |
| Organisation | University of Amsterdam |
| Country | Netherlands |
| Sector | Academic/University |
| PI Contribution | Research in theoretical physics, in particular the holographic study of chaos. |
| Collaborator Contribution | Research in theoretical physics, in particular the holographic study of chaos. |
| Impact | A research paper: "Chaotic Strings in AdS/CFT", Jan de Boer, Eva Llabrés, Juan F. Pedraza, and David Vegh, Phys. Rev. Lett. 120, 201604 |
| Start Year | 2017 |
| Description | Cambridge collaboration |
| Organisation | Massachusetts Institute of Technology |
| Country | United States |
| Sector | Academic/University |
| PI Contribution | Research in theoretical physics, more specifically in AdS/CFT. Study of the pole-skipping phenomenon in correlation functions of finite-temperature quantum field theories. |
| Collaborator Contribution | Research in theoretical physics, more specifically in AdS/CFT. |
| Impact | A research paper: "Horizon constraints on holographic Green's functions", Mike Blake, Richard A. Davison, David Vegh, JHEP 2001 (2020) 077. |
| Start Year | 2018 |
| Description | Cambridge collaboration |
| Organisation | University of Cambridge |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Research in theoretical physics, more specifically in AdS/CFT. Study of the pole-skipping phenomenon in correlation functions of finite-temperature quantum field theories. |
| Collaborator Contribution | Research in theoretical physics, more specifically in AdS/CFT. |
| Impact | A research paper: "Horizon constraints on holographic Green's functions", Mike Blake, Richard A. Davison, David Vegh, JHEP 2001 (2020) 077. |
| Start Year | 2018 |
| Description | Imperial College collaboration |
| Organisation | Imperial College London |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | I am working to deepen my understanding and further develop specific 'quantum spectral curve' constructions, building upon the foundations of my previous research and the research of my collaborator (Dr Torben Skrzypek). This involves exploring their mathematical structure, refining existing methods, and potentially uncovering new applications within the broader context of integrability and string theory. |
| Collaborator Contribution | They are working to understand and further develop specific 'quantum spectral curve' constructions. |
| Impact | Although the collaboration did not result in a paper, it helped me write a single-author paper in 2024 on a related topic ("Quantizing the folded string in AdS2"). |
| Start Year | 2023 |
| Description | King's College collaboration |
| Organisation | King's College London |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | I am co-organizing a journal club and seminar series focused on the information paradox. Additionally, I am collaborating on research related to the Sachdev-Ye-Kitaev (SYK) model and studying correlation functions in de Sitter spacetime. |
| Collaborator Contribution | Ongoing research, co-organisation of seminar series. |
| Impact | Research is still ongoing. One published paper so far: "Complex geodesics in de Sitter space" by Shira Chapman (Ben Gurion U. of Negev), Damián A. Galante, Eleanor Harris, Sameer U. Sheorey (King's Coll. London, Dept. Math), David Vegh (Queen Mary, U. of London), DOI: 10.1007/JHEP03(2023)006 |
| Start Year | 2020 |
| Description | UCL Collaboration |
| Organisation | University College London |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Study of pair-production and brane nucleation via gauge/gravity duality. |
| Collaborator Contribution | Study of pair-production and brane nucleation via gauge/gravity duality. |
| Impact | One paper has been posted on the arxiv: https://arxiv.org/abs/2101.03143 |
| Start Year | 2020 |
| Description | Uppsala Collaboration |
| Organisation | Uppsala University |
| Country | Sweden |
| Sector | Academic/University |
| PI Contribution | Study of the newly discovered generalised Ryu-Takayangi entanglement entropy, the "island" formula for the Page curve, and toy-models of gravity. |
| Collaborator Contribution | Study of the newly discovered generalised Ryu-Takayangi entanglement entropy esp. in higher dimensions. |
| Impact | A related research paper (https://arxiv.org/abs/2112.14177). Although this paper was written without the researcher at Uppsala, writing it was made possible by the collaboration. |
| Start Year | 2020 |
| Description | Black Hole Information Journal Club |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Postgraduate students |
| Results and Impact | As part of our research activities, we organized a recurring Black Hole Information Journal Club series, bringing together researchers and students to discuss recent developments in the black hole information paradox. The sessions provided a platform for knowledge exchange, fostering collaboration and engagement within the theoretical physics community. Topics covered included quantum gravity, holography, and recent advancements in the understanding of black hole entropy and information loss. This initiative helped disseminate insights from our research and encouraged interdisciplinary discussions, contributing to the broader academic conversation on fundamental questions in quantum gravity. |
| Year(s) Of Engagement Activity | 2020,2021,2022 |
| URL | http://kclstrings.wikidot.com/bhinfo |