401 citations · 4.3k across the 119 of their papers we have counts for
118 papers
Gravitational waves from super-Hubble bubbles
Pulkit S. Ghoderao, Arttu Rajantie, Danièle Steer
We consider a cosmological first-order phase transition in which bubbles of true vacuum nucleate during inflation but do not collide and percolate until the Universe has entered th…
Asymptotic limits of constrained instantons
Benjamin Elder, Kinga Gawrych, Arttu Rajantie
We revisit the topic of false vacuum decay in field theory. We focus on a toy model of a real massive scalar field with an unstable quartic potential. This model has a false vacuum…
Scalar field effective potentials in de Sitter spacetime
Lucas Vicente García-Consuegra, Arttu Rajantie
We investigate two different definitions of a scalar field effective potential in quantum field theory in de Sitter spacetime: the standard textbook definition, and the constraint…
Constrained instantons in scalar field theories
Benjamin Elder, Kinga Gawrych, Arttu Rajantie
Instantons, localised saddle points of the action, play an important role in describing non-perturbative aspects of quantum field theories, for example vacuum decay or violation of…
Curvature perturbations from vacuum transition during inflation
Björn Garbrecht, Pulkit S. Ghoderao, Arttu Rajantie
We demonstrate that in the presence of a light scalar spectator field, vacuum transitions taking place during inflation can produce large, potentially detectable non-Gaussian signa…
Magnetic monopoles -- theory overview
Arttu Rajantie
I give a theoretical overview of magnetic monopoles, focusing on the physical perspective of monopoles as hypothetical particles rather than as mathematical objects. I argue that m…