Royal Society Newton International Fellow at Queen Mary University of London. I study scattering amplitudes and correlation functions in quantum field theory, string theory, and cosmology.
My research explores how quantum interactions are encoded in scattering amplitudes and correlation functions, from particle physics and string theory to an expanding universe. I look for geometric and analytic structures that simplify these quantities, reveal relations between them, and make calculations systematic, using tools from cohomology and the theory of special functions.
Research interests
Three connected directions
Cosmology
Wavefunctions and correlators in an expanding universe
I study wavefunctions and correlation functions that describe quantum fields in an expanding universe, with the aim of understanding and simplifying their analytic structure. My work develops graphical coactions for Friedmann–Robertson–Walker integrals and their systematic expansion in multiple polylogarithms, and represents de Sitter chain wavefunctions and one-loop polygon integrands using quadrangular polylogarithms. The coaction combines graph combinatorics and cohomology to organize cosmological integrals.
Holography and energy flow
Energy correlators from AdS string amplitudes
I study energy correlators, which describe how energy is distributed in the final state of a quantum process. At strong coupling, I use string amplitudes in anti-de Sitter space to investigate these observables, including a worldsheet construction of the energy-energy correlator. Ongoing work explores string corrections, supersymmetric sources, and methods for determining correlators directly from their analytic constraints.
String amplitudes
One-loop superstrings from the nodal sphere
I study how string amplitudes can be reconstructed from their field-theory limits, using the nodal sphere to connect worldsheet geometry with scattering data. At one loop, this approach determines non-cusp contributions and reconstructs superstring correlators through 15 points. Modular consistency on the worldsheet yields additional relations among the field-theory data. I also investigate double-copy structures of string amplitudes via twisted (co)homology.
Earlier research
Celestial holography
Celestial holography recasts scattering amplitudes as correlation functions on the celestial sphere. My earlier work studied the symmetries and short-distance behavior of these functions, including their operator product expansions. My contributions explored how symmetry algebras are modified and how loop corrections and on-shell recursion help organize the structure of celestial scattering data.
Geometry and analytic structure of amplitudes
Geometric descriptions help expose the analytic structure of scattering amplitudes and Feynman integrals. My work includes symbol alphabets from tensor diagrams, one-loop integrals represented as volumes of geometric simplices called orthoschemes, and polytopes and boundary configurations for Grassmannian string integrals. These studies connect the functions appearing in amplitudes with combinatorial and geometric data.
On-shell kinematics
I developed a five-dimensional spinor-helicity framework for particles of arbitrary mass and spin. It gives a common language for the momentum and polarization data that enter scattering amplitudes. Treating different particles consistently within this framework makes it easier to construct and analyse amplitudes and to compare their structures across particle species in five dimensions.
Implementations of quadrangular polylogarithms for de Sitter chain wavefunctions and one-loop polygon integrands, together with selected core calculations.
