2 papers
gr-qc2023
Treatments and placebos for the pathologies of effective field theories
Andrew Coates, Fethi M. Ramazanoğlu
We demonstrate some shortcomings of "fixing the equations," an increasingly popular remedy for time evolution problems of effective field theories (EFTs). We compare the EFTs and t…
gr-qc2023
Loss of hyperbolicity and tachyons in generalized Proca theories
Kıvanç İ. Ünlütürk, Andrew Coates, Fethi M. Ramazanoğlu
Various groups recently demonstrated that the time evolution of simplest self-interacting vector fields, those with self-interaction potentials, can break down after a finite durat…