11-14 September 2019
University of Warsaw
Europe/Warsaw timezone
The hiccupping Universe
Presented by Dr. Daniele TERESI
on
13 Sep 2019
from
14:15
to
14:30
Session:
Parallel 3
Content
We consider a scalar field with a bottom-less linear potential, finding that cosmologies unavoidably end up with a crunch, even in scenarios compatible with the observed positive cosmological constant. Assuming that rebounces avoid singularities, this generates a new kind of multiverse: the universe undergoes cycles with different cosmological constants, all with finite lifetime regardless of the sign. This novel "temporal" multiverse avoids some of the usual ambiguities present in the standard "spatial" one. Moreover, if a "hiccupping" mechanism changes the vacuum energy by a small amount at each cycle, this dynamics selects a small vacuum energy and becomes the most likely source of universes with anthropically small cosmological constant. Its probability distribution could avoid the gap of 2 orders of magnitude that seems left by standard anthropic selection.
Place
Location: University of Warsaw
Address: Faculty of Physics
Pasteura Str. 5
02-093 Warsaw
Poland
Room: 1.40