4 papers
Preheating in New Inflation
Mariel Desroche, Gary N. Felder, Jan M. Kratochvil +1
During the last ten years a detailed investigation of preheating was performed for chaotic inflation and for hybrid inflation. However, nonperturbative effects during reheating in…
Current Observational Constraints on Cosmic Doomsday
Yun Wang, Jan Michael Kratochvil, Andrei Linde +1
In a broad class of dark energy models, the universe may collapse within a finite time t_c. Here we study a representative model of dark energy with a linear potential, V(ϕ)=V_0(1+…
Testing the Cosmological Constant as a Candidate for Dark Energy
Jan Kratochvil, Andrei Linde, Eric V. Linder +1
It may be difficult to single out the best model of dark energy on the basis of the existing and planned cosmological observations, because many different models can lead to simila…
Observational Bounds on Cosmic Doomsday
Renata Kallosh, Jan Kratochvil, Andrei Linde +2
Recently it was found, in a broad class of models, that the dark energy density may change its sign during the evolution of the universe. This may lead to a global collapse of the…