Theoretical Cosmology meeting
Speakers: Toshifumi Noumi (Kobe University) and Alex Cole (University of Wisconsin-Madison). Location: Amsterdam.
14:00 – 15:00 Toshifumi Noumi (Kobe University) - Enlarging the scope of the cosmological collider: Beyond the positivity bounds
15:00 – 15:30 Coffee Break
15:30 – 16:30 Alex Cole (University of Wisconsin-Madison) - Simplices in the Sky - Constraining Cosmology with Computational Topology
16:30 – 17:30 Borrel
Toshifumi Noumi (Kobe University
Enlarging the scope of the cosmological collider: Beyond the positivity bounds
Abstract: The energy scale of inflation could be as high as 10^14 GeV, hence it is a phenomenon at the highest energy scale we may explore. Primordial non-Gaussianities can then be thought of as a 10^14 GeV collider (dubbed the cosmological collider), which may be used to probe new particles at the inflationary scale.
In this talk I will discuss how to read of the mass and spin of new particles at various scales from non-Gaussianities. In particular I will demonstrate that signs of inflaton effective interactions (which are not constrained by the positivity bounds) are useful to probe spins of particles heavier than the Hubble scale.
Alex Cole (University of Wisconsin-Madison)
Simplices in the Sky — Constraining Cosmology with Computational Topology
Abstract: In this talk, I will describe how persistent homology, a somewhat recent development in computational topology and the main pillar of Topological Data Analysis (TDA), is a useful tool for characterizing cosmological observables in the search for new physics. After motivating the utility of developing new perspectives for analyzing cosmological data, I will review the basics of persistent homology. I will then describe how persistent homology connects to several topological statistics that have appeared previously in the cosmology literature, and how it is strictly more powerful than these statistics. To see how much mileage our improved method gives us, I will outline two applications of persistent homology to cosmology: one project with G. Shiu on primordial non-Gaussianity and the CMB (1712.08159), and work in progress with G. Shiu and M. Biagetti regarding LSS.
The meeting will take place in Amsterdam, at Nikhef, Science Park 105 in room H331.
Jan Pieter van der Schaar, cosmology.amsterdam
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