Related papers: Celestial Mellin Amplitudes
There are holographic superconformal theories in all dimensions between two and six which allow arbitrary tree-level four-point functions to be fixed by basic consistency conditions. Although Mellin space is usually the most efficient…
We study Carrollian amplitudes of massless scalars in (1+2) Minkowski space. Using the prescription recently shown by Alday et al. [JHEP 03 (2025) 158] originally designed for the AdS4 Witten diagrams, we show that AdS3 Witten diagrams in…
The four-dimensional (4D) Lorentz group $SL(2,\mathbb{C})$ acts as the two-dimensional (2D) global conformal group on the celestial sphere at infinity where asymptotic 4D scattering states are specified. Consequent similarities of 4D flat…
We compute celestial amplitudes corresponding to the exact S-matrix of the 2d O(N)-symmetric nonlinear sigma model. Celestial amplitudes for two-dimensional integrable S-matrices simplify to Fourier transforms. Due to the connection between…
Both celestial and momentum space amplitudes in four dimensions are beset by divergences resulting from spacetime translation and sometimes scale invariance. In this paper we consider a (linearized) marginal deformation of the celestial CFT…
The relation between celestial holography and Liouville field theory is investigated. It is shown that duality relations between different Selberg type integrals appearing in the Coulomb gas realization of Liouville correlation functions…
We describe in more detail our approach to the conformal bootstrap which uses the Mellin representation of $CFT_d$ four point functions and expands them in terms of crossing symmetric combinations of $AdS_{d+1}$ Witten exchange functions.…
Continuing our program of deriving aspects of celestial holography from string theory, we extend the Roiban-Spradlin-Volovich-Witten (RSVW) formalism to celestial amplitudes. We reformulate the tree-level maximally-helicity-violating (MHV)…
We compute scattering amplitudes involving one massive scalar and two, three, or four gravitons. We show that when the conformal dimension of the massive scalar is set to zero, the resulting celestial correlators depend {\it only} on the…
We transform superstring scattering amplitudes into the correlation functions of primary conformal fields on two-dimensional celestial sphere. The points on celestial sphere are associated to the asymptotic directions of (light-like)…
In celestial holography, four-dimensional scattering amplitudes are considered as two-dimensional conformal correlators of a putative two-dimensional celestial conformal field theory (CCFT). The simplest way of converting momentum space…
We compute the Mellin amplitude of the planar four-point correlator of weight-two half-BPS operators in $\mathcal{N}=4$ SYM at one and two-loop orders in the small 't Hooft coupling expansion. The two-loop Mellin amplitude has an infinite…
In 2507.17558, we provide a map from a scalar theory on $(D+2)$-dimensional Minkowski spacetime to a scalar theory with a continuous mass spectrum on $(D+1)$-dimensional de Sitter spacetime, and propose a link between celestial amplitudes…
We propose a new program for computing a certain integrand of scattering amplitudes of four-dimensional gauge theories which we call the \textit{form factor integrand}, starting from 6d holomorphic theories on twistor space. We show that…
We show that the Mellin transform of an $n$-point tree level MHV gluon scattering amplitude, also known as the celestial amplitude in pure Yang-Mills theory, satisfies a system of $(n-2)$ linear first order partial differential equations…
We show that the one-loop on-shell four-point scattering amplitude of massless $\phi^4$ scalar field theory in 4D Minkowski space time, when Mellin transformed to the Celestial sphere at infinity, transforms covariantly under the global…
We calculate the Mellin moments of the $O(\alpha_s^2)$ coefficient functions for the unpolarized and polarized fragmentation functions. They can be expressed in terms of multiple finite harmonic sums of maximal weight {\sf w = 4}. Using…
We start by constructing a conformally covariant improvement of the celestial light transform which keeps track of the mixing between incoming and outgoing states under finite Lorentz transformations in $\mathbb{R}^{2,2}$. We then compute…
We explore the Mellin space representation for the collinear limit of $N$-point energy correlators in ${\cal N}=4$ super-Yang-Mills theory. We show that these correlators can be written as integro-differential operators acting on star…
We explore the use of the differential representation of AdS amplitudes to compute Witten diagrams. The differential representation expresses AdS amplitudes in terms of conformal generators acting on contact Witten diagrams, which allows us…