Twistor Sigma Models

Atul Sharma is a leading expert in the study of scattering amplitudes and twistor theory. He currently holds a Black Hole Initiative postdoctoral fellowship at Harvard University, where he works on the hunt for flat space holography. He graduated B.Sc. from the Indian Institute of Science, Bangalore in 2017, following which he obtained an MASt in Applied Mathematics from the University of Cambridge and a D.Phil. in Mathematics from the University of Oxford. His work tackles scattering amplitudes in gauge theory and gravity, with a special emphasis on decoding hidden mathematical structures. It has helped in building top-down models of celestial holography, discovering remarkable formulae for amplitudes in curved backgrounds, and understanding the asymptotic symmetries of nature. He has also worked on applications of twistor theory to complex algebraic geometry, developing many new techniques that form a core part of this thesis.

Introduction.- Twistors for Flat Space.- Sigma Models and Hyperkähler Geometry.- Graviton Scattering in Flat Space.-  Celestial Holography.- Twistors for SD Radiative Space-Times.