Title Information
Title
From Celestial Amplitudes to Twisted Cohomology: New Perspectives on Quantum Scattering
Type of Resource (primo)
dissertations
Name: Personal
Name Part
Bhardwaj, Rishabh
Role
Role Term: Text
creator
Name: Personal
Name Part
Alexander, Stephon
Role
Role Term: Text
Reader
Name: Personal
Name Part
Fan, JiJi
Role
Role Term: Text
Reader
Name: Personal
Name Part
Spradlin, Marcus
Role
Role Term: Text
Advisor
Name: Corporate
Name Part
Brown University. Department of Physics
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2025
Physical Description
Extent
21, 178 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2025
Genre (aat)
theses
Abstract
In this thesis, we study the mathematical structures underlying scattering amplitudes, with a focus on loop-level corrections in celestial conformal field theory, twisted cohomology in higher genus string amplitudes, and q-deformations of the Veneziano amplitude. These investigations reveal novel connections between scattering amplitudes and celestial symmetries, explore a novel formalism to study higher genus string amplitudes, as well as provide new perspectives on UV-completions and dual resonant amplitudes. First, we explore loop-level corrections to collinear limits and soft theorems in celestial conformal field theory. By analyzing their impact on gluon operator product expansions (OPEs), we uncover the logarithmic structure of celestial CFT and demonstrate how these corrections alter the infinite tower of conserved charges forming the S-algebra. This study introduces a new class of non-local soft charges with logarithmic partners, providing insights into celestial CFT spectra as well as its integrability. Secondly, we investigate the worldsheet origins of the Coon amplitude, a q-deformation of the Veneziano amplitude, through a conformal field theory based on the SUq(2) quantum group. By constructing a family of deformations and exploring their analytic continuation into extended kine- matic space, we uncover a new class of dual resonant amplitudes that respect locality, unitarity, causality, and UV finiteness. These amplitudes are compatible with the S-matrix bootstrap and provide a unique connection to q-deformed worldsheet theories. Finally, we reformulate loop-level string amplitudes using intersection theory and twisted cohomology. We study the twisted (co)homology of Riemann-Wirtinger integrals, a family of genus-one integrals related to one-loop string amplitudes in chiral splitting. These integrals, which leave the loop momentum, modulus, and one puncture unintegrated, are analytically tractable and capture key properties of string amplitudes. Using intersection numbers to define an inner product on differential forms, I derive the Gauss-Manin connection for two twisted cohomology bases, independently verifying earlier results. Furthermore, we establish a double-copy formula for the closed-string analogues of these integrals via intersection indices. This genus-one KLT-like kernel extends the KLT framework to meromorphic integrals over the torus, highlighting the interplay between twisted co-homology and double-copy structures at loop level.
Subject
Topic
scattering amplitudes
Subject
Topic
algebraic geometry
Subject
Topic
celestial holography
Subject
Topic
string theory
Subject
Topic
conformal field theory
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01085113")
Topic
Quantum groups
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01102754")
Topic
S-matrix theory
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20250310