6 papers
Approximating Feynman integrals using complete monotonicity and Stieltjes properties
Sara Ditsch, Johannes M. Henn, Prashanth Raman
We present two novel approaches for the numerical evaluation of Feynman integrals based on their universal analytic properties related to positivity, namely complete monotonicity (…
Lecture Notes on Positivity Properties of Scattering Amplitudes
Prashanth Raman
We review completely monotone (CM) and Stieltjes functions, which are classes of functions obeying an infinite hierarchy of positivity constraints. While these are classical concep…
Approximating Feynman Integrals Using Complete Monotonicity and Stieltjes Properties
Sara Ditsch, Johannes M. Henn, Prashanth Raman
We introduce two novel numerical approaches for computing Feynman integrals based on their complete monotonicity (CM) and Stieltjes properties. The first method uses that scalar Fe…
Canonical Forms as Dual Volumes
Elia Mazzucchelli, Prashanth Raman
We study dual volume representations of canonical forms for positive geometries in projective spaces, expressing their rational canonical functions as Laplace transforms of measure…
Mastering Cosmological Amplitudes Using Generalized Ramanujan's Theorem
Prashanth Raman, Qinglin Yang
We present a systematic method for computing cosmological amplitudes, including in-in correlators and wavefunction coefficients, in FRW spacetime. Specializing to cases with confor…
Positivity properties of scattering amplitudes
Johannes Henn, Prashanth Raman
We investigate positivity properties in quantum field theory (QFT). We provide evidence,and in some case proofs, that many building blocks of scattering amplitudes, and in some cas…