74 citations · 88 across the 6 of their papers we have counts for
6 papers
-matrix positivity without Lorentz invariance: a case study
Lam Hui, Ioanna Kourkoulou, Alberto Nicolis +2
We investigate the analytic structure of scattering amplitudes in theories in which Lorentz invariance is spontaneously broken. We do so by computing and studying the S-matrix for…
Apparently superluminal superfluids
Ioanna Kourkoulou, Michael J. Landry, Alberto Nicolis +1
We consider the superfluid phase of a specific renormalizable relativistic quantum field theory. We prove that, within the regime of validity of perturbation theory and of the supe…
Low-temperature thermal corrections to a superfluid's equation of state
Ioanna Kourkoulou, Alberto Nicolis, Klaas Parmentier
Using effective field theory methods, we calculate the low-temperature phonon thermal partition function for a generic superfluid, thus providing the leading thermal corrections to…
An improved Noether's theorem for spacetime symmetries
Ioanna Kourkoulou, Alberto Nicolis, Guanhao Sun
We exploit an ambiguity somewhat hidden in Noether's theorem to derive systematically, for relativistic field theories, the stress-energy tensor's improvement terms that are associ…
A technical analog of the cosmological constant problem and a solution thereof
Ioanna Kourkoulou, Alberto Nicolis, Guanhao Sun
The near vanishing of the cosmological constant is one of the most puzzling open problems in theoretical physics. We consider a system, the so-called framid, that features a techni…
Pure states in the SYK model and nearly- gravity
Ioanna Kourkoulou, Juan Maldacena
We consider pure states in the SYK model. These are given by a simple local condition on the Majorana fermions, evolved over an interval in Euclidean time to project on to low ener…