HEP Theory Journal Club

String Gases and the Swampland

Samuel Laliberté

McGill

It was recently conjectured that all scalar fields arising from string theory must have a potential which satisfies |∇V|/V ≥ c/Mp, where c is some constant of order one. This bound, called the de Sitter conjecture, is motivated by two key arguments. First, the conjecture is supported by multiple examples in string theory. Second, we expect that when the de Sitter conjecture is violated, a massive tower of states becomes massless leading to a breakdown of the effective field theory. Although the de Sitter conjecture is widely used, there have been very few attempts to explicitly include the effects of a massive tower of states in low energy effective field theories. In this talk, I will discuss a way to include the massive tower of string states as a string gas and discuss the implications for low energy effective field theories.