HEP Theory Journal Club

Causality and (scalar) effective theories

Simon Caron-Huot

McGill

Dispersion relations are statements of causality. They give sum rules connecting infrared and ultraviolet physics and which enforce the absence of superluminal communication. One key motivation, which will resonate with Claudia de Rham's Monday seminar, is to theoretically bound modifications of gravity. I will present a related story involving scalar particles, and ongoing work mapping out the space of consistent effective theories. Causality will be seen to imply a sharp version of dimensional analysis scaling.