BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Observing the Big Bang - ECPv5.3.1//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Observing the Big Bang
X-ORIGINAL-URL:http://cosmology.nl
X-WR-CALDESC:Events for Observing the Big Bang
BEGIN:VTIMEZONE
TZID:Europe/Amsterdam
BEGIN:DAYLIGHT
TZOFFSETFROM:+0100
TZOFFSETTO:+0200
TZNAME:CEST
DTSTART:20210328T010000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0200
TZOFFSETTO:+0100
TZNAME:CET
DTSTART:20211031T010000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Europe/Amsterdam:20210507T143000
DTEND;TZID=Europe/Amsterdam:20210507T170000
DTSTAMP:20260502T075635
CREATED:20210428T093735Z
LAST-MODIFIED:20210506T144048Z
UID:496-1620397800-1620406800@cosmology.nl
SUMMARY:Groningen Spring 2021
DESCRIPTION:Groningen\, May 7th. \nThis meeting will take place via remote connection. Here the information for connecting: \nTime: May 7\, 2021 02:30 PM Amsterdam Time \nJoin Zoom Meeting\nZoom Link\nMeeting ID: 890 4133 2437\nPassword: 506154 \n \n14:30-15:10 CET: Talk by  David Stefanyszyn (DAMTP)  \nTitle:  From locality and unitarity to cosmological correlators  \nAbstract: \n The on-shell approach to computing scattering amplitudes has lead to tremendous progress in particle physics. The combination of symmetries\, locality and unitarity allows one to efficiently explore the space of consistent effective theories of massless particles without using Lagrangians or introducing gauge redundancies. Effort has recently turned to applying a similar logic to “bootstrap” the fundamental observables in cosmology\, namely cosmological correlators that live on the late-time boundary of an approximately de-Sitter spacetime. After outlining the success of the on-shell approach for particle physics\, I will explain how we can efficiently bootstrap three and four point functions in the effective field theory of inflation by using a small number of physical principles.   \n15:15-15:55 CET: Talk by  Gonzalo Palma (Chile University) \nTitle:   Seeding primordial black holes in multifield inflation 
 \nAbstract: \n The inflationary origin of primordial black holes (PBHs) relies on a large enhancement of the power spectrum of the primordial curvature fluctuation ζ at wavelengths much shorter than those relevant for CMB anisotropies. This is typically achieved in models where ζ evolves without interacting significantly with additional scalar degrees of freedom. However\, quantum gravity inspired models are characterized by moduli spaces with highly curved geometries and a large number of scalar fields that could vigorously interact with ζ. In this talk I will discuss how isocurvature fluctuations can mix with ζ inducing large enhancements of its amplitude. This occurs whenever the inflationary trajectory experiences rapid turns in the field space of the model leading to amplifications that are exponentially sensitive to the total angle swept by the turn\, which induce characteristic observable signatures on the power spectrum of ζ. I will also discuss other characteristic signatures\, such as the generation of gravity waves.  \n16:00-16:40 CET: Talk by  Katelin Schutz (MIT)  \nTitle:  Making dark matter out of light: the cosmology of sub-MeV freeze-in \n \nAbstract: \n Dark matter could be a “thermal-ish” relic of freeze-in\, where the dark matter is produced by extremely feeble interactions with Standard Model particles dominantly at low temperatures. In this talk\, I will discuss how sub-MeV dark matter can be made through freeze-in\, accounting for a dominant channel where the dark matter gets produced by the decay of plasmons (photons that have an in-medium mass in the primordial plasma of our Universe). I will also explain how the resulting non-thermal dark matter velocity distribution can impact cosmological observables.\n \n16:45 CET:  social virtual borrel and socializing
URL:http://cosmology.nl/event/groningen-spring-2021/
CATEGORIES:THC meeting
END:VEVENT
END:VCALENDAR