All Outputs (51)

Towards a flat space Carrollian hologram from AdS₄/CFT₃ (2025)
Journal Article
Lipstein, A., Ruzziconi, R., & Srikant, A. Y. (2025). Towards a flat space Carrollian hologram from AdS₄/CFT₃. Journal of High Energy Physics, 2025(6), Article 73. https://doi.org/10.1007/jhep06%282025%29073

Finding a concrete example holography in four dimensional asymptotically flat space is an important open problem. A natural strategy is to take the flat space limit of the celebrated AdS₄/CFT₃ correspondence, which relates M-theory in AdS₄×S⁷ to a ce... Read More about Towards a flat space Carrollian hologram from AdS₄/CFT₃.

Pure connection formalism and Plebanski’s second heavenly equation (2025)
Journal Article
Krasnov, K., & Lipstein, A. (2025). Pure connection formalism and Plebanski’s second heavenly equation. Journal of High Energy Physics, 2025(3), Article 152. https://doi.org/10.1007/jhep03%282025%29152

Plebanski’s second heavenly equation reduces the problem of finding a self-dual Einstein metric to solving a non-linear second-order PDE for a single function. Plebanski’s original equation is for self-dual metrics obtained as perturbations of the fl... Read More about Pure connection formalism and Plebanski’s second heavenly equation.

The subtle simplicity of cosmological correlators (2025)
Journal Article
Chowdhury, C., Lipstein, A., Mei, J., Sachs, I., & Vanhove, P. (2025). The subtle simplicity of cosmological correlators. Journal of High Energy Physics, 2025(3), Article 7. https://doi.org/10.1007/jhep03%282025%29007

We investigate cosmological correlators for conformally coupled ϕ4 theory in four-dimensional de Sitter space. These in-in correlators differ from scattering amplitudes for massless particles in flat space due to the spacelike structure of future inf... Read More about The subtle simplicity of cosmological correlators.

Light-cone actions and correlators of self-dual theories in AdS₄ (2025)
Journal Article
Chowdhury, C., Doran, G., Lipstein, A., Monteiro, R., Nagy, S., & Singh, K. (2025). Light-cone actions and correlators of self-dual theories in AdS₄. Journal of High Energy Physics, 2025(1), Article 172. https://doi.org/10.1007/JHEP01%282025%29172

Self-dual Yang-Mills and Einstein gravity in Euclidean AdS4 are useful toy models because they can be described by simple scalar Lagrangians exhibiting a new manifestation of the colour/kinematics duality, as recently shown by two of the authors. In... Read More about Light-cone actions and correlators of self-dual theories in AdS₄.

3d Carrollian Chern-Simons theory & 2d Yang-Mills (2024)
Journal Article
Bagchi, A., Lipstein, A., Mandlik, M., & Mehra, A. (2024). 3d Carrollian Chern-Simons theory & 2d Yang-Mills. Journal of High Energy Physics, 2024(11), Article 6. https://doi.org/10.1007/jhep11%282024%29006

With the goal of building a concrete co-dimension one holographically dual field theory for four dimensional asymptotically flat spacetimes (4d AFS) as a limit of AdS4/CFT3, we begin an investigation of 3d Chern-Simons matter (CSM) theories in the Ca... Read More about 3d Carrollian Chern-Simons theory & 2d Yang-Mills.

Self-dual cosmology (2024)
Journal Article
González, M. C., Lipstein, A., & Nagy, S. (2024). Self-dual cosmology. Journal of High Energy Physics, 2024(10), Article 183. https://doi.org/10.1007/jhep10%282024%29183

We construct cosmological spacetimes with a self-dual Weyl tensor whose dynamics are described by conformally coupled scalars with only cubic self-interactions. Similar to the previously discovered cases in flat and (Anti) de Sitter backgrounds, the... Read More about Self-dual cosmology.

Soft limits of gluon and graviton correlators in Anti-de Sitter space (2024)
Journal Article
Chowdhury, C., Lipstein, A., Mei, J., & Mo, Y. (2024). Soft limits of gluon and graviton correlators in Anti-de Sitter space. Journal of High Energy Physics, 2024(10), Article 70. https://doi.org/10.1007/jhep10%282024%29070

We derive formulae for the soft limit of tree-level gluon and graviton correlators in Anti-de Sitter space, which arise from Feynman diagrams encoding the Weinberg soft theorems in flat space. Other types of diagrams can also contribute to the soft l... Read More about Soft limits of gluon and graviton correlators in Anti-de Sitter space.

Hidden conformal symmetry in AdS2×S2 beyond tree level (2024)
Journal Article
Heslop, P., Lipstein, A., & Santagata, M. (2024). Hidden conformal symmetry in AdS2×S2 beyond tree level. Physical Review D, 110(6), Article L061902. https://doi.org/10.1103/physrevd.110.l061902

Correlators of N=2 hypermultiplets with two-derivative interactions in AdS2×S2 exhibit a hidden four-dimensional conformal symmetry which allows one to repackage all tree-level four-point correlators into a single four-dimensional object correspondin... Read More about Hidden conformal symmetry in AdS2×S2 beyond tree level.

Six-dimensional correlators from a five-dimensional operator product expansion (2024)
Journal Article
Lambert, N., Lipstein, A., & Mouland, R. (2024). Six-dimensional correlators from a five-dimensional operator product expansion. Journal of High Energy Physics, 2024(6), Article 055. https://doi.org/10.1007/jhep06%282024%29055

In this letter we discuss the operator product expansion of scalar operators in five-dimensional field theories with an SU(1, 3) × U(1) spacetime symmetry. Such theories arise by a novel conformal null reduction of six-dimensional Lorentzian conforma... Read More about Six-dimensional correlators from a five-dimensional operator product expansion.

Graviton trispectrum from gluons (2023)
Journal Article
Armstrong, C., Goodhew, H., Lipstein, A., & Mei, J. (2023). Graviton trispectrum from gluons. Journal of High Energy Physics, 2023(8), Article 206. https://doi.org/10.1007/jhep08%282023%29206

The tree-level wavefunction coefficient for four gravitons in de Sitter space was recently bootstrapped using the Cosmological Optical Theorem, flat space limit, and Manifestly Local Test [1]. Inspired by the double copy for scattering amplitudes, we... Read More about Graviton trispectrum from gluons.

Self-Dual Gravity and Color-Kinematics Duality in AdS4 (2023)
Journal Article
Lipstein, A., & Nagy, S. (2023). Self-Dual Gravity and Color-Kinematics Duality in AdS4. Physical Review Letters, 131(8), Article 081501. https://doi.org/10.1103/physrevlett.131.081501

New recursion relations for tree-level correlators in anti–de Sitter spacetime (2022)
Journal Article
Armstrong, C., Gomez, H., Lipinski Jusinskas, R., Lipstein, A., & Mei, J. (2022). New recursion relations for tree-level correlators in anti–de Sitter spacetime. Physical Review D, 106(12), https://doi.org/10.1103/physrevd.106.l121701

We present for the first time classical multiparticle solutions in anti–de Sitter space (AdS) involving scalars, gluons, and gravitons. They are recursively defined through multiparticle currents which reduce to Berends-Giele currents in the flat spa... Read More about New recursion relations for tree-level correlators in anti–de Sitter spacetime.

Enhanced soft limits in de Sitter space (2022)
Journal Article
Armstrong, C., Lipstein, A., & Mei, J. (2022). Enhanced soft limits in de Sitter space. Journal of High Energy Physics, 2022(12), Article 64. https://doi.org/10.1007/jhep12%282022%29064

In flat space, the scattering amplitudes of certain scalar effective field theories exhibit enhanced soft limits due to the presence of hidden symmetries. In this paper, we show that this phenomenon extends to wavefunction coefficients in de Sitter s... Read More about Enhanced soft limits in de Sitter space.

Yangian Symmetry in Five Dimensions (2022)
Journal Article
Lipstein, A., & Orchard, T. (2022). Yangian Symmetry in Five Dimensions. Physical Review Letters, 129(23), Article 231602. https://doi.org/10.1103/physrevlett.129.231602

Quantum gravity in AdS7×S4 is dual to a six-dimensional (6D) superconformal field theory, known as the 6D (2,0) theory, which is very challenging to describe because it lacks a conventional Lagrangian description. On the other hand, certain null redu... Read More about Yangian Symmetry in Five Dimensions.

Effective field theories and cosmological scattering equations (2022)
Journal Article
Armstrong, C., Gomez, H., Jusinskas, R. L., Lipstein, A., & Mei, J. (2022). Effective field theories and cosmological scattering equations. Journal of High Energy Physics, 2022(8), Article 54. https://doi.org/10.1007/jhep08%282022%29054

We propose worldsheet formulae for correlators of the massive non-linear sigma model (NLSM), scalar Dirac-Born-Infeld (DBI), and special Galileon (sGal) theories in de Sitter momentum space in terms of the recently proposed cosmological scattering eq... Read More about Effective field theories and cosmological scattering equations.

Cosmological scattering equations at tree-level and one-loop (2022)
Journal Article
Gomez, H., Jusinskas, R. L., & Lipstein, A. (2022). Cosmological scattering equations at tree-level and one-loop. Journal of High Energy Physics, 2022(7), Article 4. https://doi.org/10.1007/jhep07%282022%29004

We recently proposed a formula for tree-level n-point correlators of massive phi^4 theory in de Sitter momentum space which consists of an integral over n punctures on the Riemann sphere and differential operators in the future boundary dubbed the co... Read More about Cosmological scattering equations at tree-level and one-loop.

Higher-dimensional symmetry of AdS2×S2 correlators (2022)
Journal Article
Abl, T., Heslop, P., & Lipstein, A. E. (2022). Higher-dimensional symmetry of AdS2×S2 correlators. Journal of High Energy Physics, 2022(3), Article 76. https://doi.org/10.1007/jhep03%282022%29076

It was recently shown that IIB supergravity on AdS5×S5 enjoys 10d conformal symmetry and that superstring theory on this background can be described using a 10d scalar effective field theory. In this paper we adapt these two complementary approaches... Read More about Higher-dimensional symmetry of AdS2×S2 correlators.

Five-dimensional path integrals for six-dimensional conformal field theories (2022)
Journal Article
Lambert, N., Lipstein, A., Mouland, R., & Richmond, P. (2022). Five-dimensional path integrals for six-dimensional conformal field theories. Journal of High Energy Physics, 2022(2), Article 151. https://doi.org/10.1007/jhep02%282022%29151

In this paper we derive Ward-Takahashi identities from the path integral of supersymmetric five-dimensional field theories with an SU(1,3) spacetime symmetry in the presence of instantons. We explicitly show how SU(1,3) is enhanced to SU(1,3)×U(1) wh... Read More about Five-dimensional path integrals for six-dimensional conformal field theories.

Cosmological Scattering Equations (2021)
Journal Article
Gomez, H., Lipinski Jusinskas, R., & Lipstein, A. (2021). Cosmological Scattering Equations. Physical Review Letters, 127(25), Article 251604. https://doi.org/10.1103/physrevlett.127.251604

We propose a worldsheet formula for tree-level correlation functions describing a scalar field with arbitrary mass and quartic self-interaction in de Sitter space, which is a simple model for inflationary cosmology. The correlation functions are loca... Read More about Cosmological Scattering Equations.

Instanton worldlines in five-dimensional Ω-deformed gauge theory (2021)
Journal Article
Lambert, N., Lipstein, A., Mouland, R., & Richmond, P. (2021). Instanton worldlines in five-dimensional Ω-deformed gauge theory. Journal of High Energy Physics, 2021(9), Article 086. https://doi.org/10.1007/jhep09%282021%29086

We discuss the Bosonic sector of a class of supersymmetric non-Lorentzian five-dimensional gauge field theories with an SU(1,3) conformal symmetry. These actions have a Lagrange multiplier which imposes a novel Ω-deformed anti-self-dual gauge field c... Read More about Instanton worldlines in five-dimensional Ω-deformed gauge theory.