Theoretical Cosmology meetings
To actively encourage the field of theoretical cosmology and to set an informal stage for the exchange of ideas, the Dutch theoretical cosmology community organizes Friday afternoon meetings approximately 6 times a year — usually on the first Friday of the month. The meetings typically start in the afternoon with a main speaker, followed by a short break to continue with another seminar or journal club discussion on some topic of current interest. We end the afternoon with drinks. The supporting institutes in Leiden, Amsterdam, Groningen, Utrecht where recently joined by the strings and cosmology group in Leuven and take turns in hosting the event.
- This event has passed.
Groningen Winter 2016
02/12/2016 @ 12:00 - 18:00
RUG Groningen, December 2, 2016
The meeting will take place in room 216 of the University College, Hoendiepskade 23/24, walking distance from Groningen Central Station. We will start at 11:30 and there will be 3 talks, the schedule is as follows
11:30-12:30 Talk by Timm Wrase (TU Vienna)
Title: dS vacua and inflation in supergravity
Abstract: I will discuss how a new ingredient, the so called nilpotent chiral superfield, has led to tremendous progress in cosmological model building in the context of supergravity.
12:30-14:00 Lunch break
14:00-15:00 Talk by Gui Pimentel (UvA Amsterdam)
Title: Symmetries of Cosmological Fluctuations
Abstract: The assumption that inflationary fluctuations realize de Sitter isometries – an analogue of imposing Lorentz invariance of scattering amplitudes in flat space – imply that various primordial correlation functions are essentially fixed by symmetries. I will present (some recent, others not so recent) results related to the scalar and tensor power spectra and bispectra, which follow from symmetry considerations. If conformal symmetry is explicitly broken, non-Gaussianity is enhanced, at the cost of making them more model-dependent. In a very optimistic scenario, these large non-Gaussianities would permit us to use the early universe as a particle collider, and perform spectroscopy of heavy fields during inflation.
15:00-15:30 Coffee Break
15:30-16:30 Talk by David Stefanyszyn (RUG Groningen)
Title: Scalar field scattering amplitudes, soft limits and symmetries
Abstract: I will discuss recent developments in classifying and constructing effective field theories of a massless scalar field based on the behaviour of scattering amplitudes in the limit where the momentum of one particle is taken soft. The relationship between non-trivial behaviour of the soft amplitudes and the presence of symmetries will be explained and by studying amplitudes for a very general class of theories, all symmetries beyond a constant shift of the scalar will be identified.