KICP Seminars & Colloquia
KICP Seminars & Colloquia, Current and Future
Seminar schedule for Current (Summer 2015) & Future Quarters
|July 21, 2015|
Open Group seminar
|Modeling and measuring CMB lensing in the cross-correlation era [Abstract]|
|August 6, 2015|
Open Group seminar
|The invisible landscape - Weak lensing mass maps with the Dark Energy Survey and beyond [Abstract]|
|October 2, 2015|
Friday noon seminar
Institute d'Astrophysique Paris
|Oscillations in the CMB bispectrum [Abstract]|
|October 16, 2015|
Friday noon seminar
New York University
|Healthy solutions in the decoupling limit of quasi-dilaton theory [Abstract]|
|October 28, 2015|
Johns Hopkins University
|The Future of Cosmological Physics: New Avenues|
- October 28, 2015 | 3:00 PM | BSLC 115
The Future of Cosmological Physics: New Avenues
Marc Kamionkowski, Johns Hopkins University
Note: Reception at 4 PM in the LASR conference room.
Friday noon seminars
- October 2, 2015 | 12:00 PM | LASR conference room
Oscillations in the CMB bispectrum
Moritz Munchmeyer, Institute d'Astrophysique Paris
Oscillating signatures in the correlation functions of the primordial density perturbations are predicted by a variety of inflationary models. A theoretical mechanism that has attracted much attention is a periodic shift symmetry as implemented in axion monodromy inflation. This symmetry leads to resonance non-gaussianities, whose key feature are logarithmically stretched oscillations. Oscillations are also a generic consequence of excited states during inflation and of sharp features in the potential. Oscillating shapes are therefore a very interesting experimental target.
After giving an overview of these motivations, I will discuss how to search for these signatures in the CMB. Fast oscillations are difficult to search for with traditional estimation techniques, and I will demonstrate how targeted expansions, that exploit the symmetry properties of the shapes, allow to circumvent these difficulties. As a member of the Planck collaboration, I will discuss the Planck results that have been obtained using these methods in the bispectrum, as well as a joint search using bispectrum and power spectrum. Due to their low overlap with other non-gaussian shapes, oscillating bispectrum shapes are not exhaustively constrained and a potential discovery is therefore not yet ruled out.
My talk will be based in particular on arxiv:1412.3461, arxiv:1505.05882 and Planck publications on inflation and non-gaussianities.
- October 16, 2015 | 12:00 PM | LASR conference room
Healthy solutions in the decoupling limit of quasi-dilaton theory
Rampei Kimura, New York University
Quasidilaton massive gravity is an extension of massive General Relativity to a theory with additional scale invariance and approximate internal Galilean symmetry. In this talk, I will present a detailed study of the spherically symmetric solutions which are free of ghosts, tachyons, gradient instability, and superluminality for all propagating modes in a theory of quasidilaton.
Open group seminars
- July 21, 2015 | 1:00 PM | LASR Conference Room
Modeling and measuring CMB lensing in the cross-correlation era
Giulio Fabbian, SISSA-Trieste
Being less sensitive to systematic effects, the cross-correlations between Cosmic Microwave Background (CMB) data sets and large-scale structures surveys are expected to provide excellent astrophysical and cosmological constraints in the upcoming years. In order to capitalize on the advantages offered by these joint analysis techniques, an accurate physical modeling of both the observables involved is required. I will present recent numerical results on CMB lensing simulations aiming at including effects of non-linear evolution of large-scale structures beyond the Born approximation on large fraction of the sky. If time allows, I will also discuss the status of the POLARBEAR experiment and its upgrade, the Simons Array, which will provide one of the best CMB data set for cross-correlation studies.
- August 6, 2015 | 2:00 PM | LASR Conference Room
The invisible landscape - Weak lensing mass maps with the Dark Energy Survey and beyond
Chihway Chang, ETH Zurich
Our view of the Universe is distorted due to gravitational lensing. These distortions help us understand the content and history of the Universe. In this talk I will describe our recent work where we used the Dark Energy Survey Science Verification data to make a large weak lensing mass map of a slice of our Universe. I then discuss a variety of topics that can be investigated with these maps and in combination with other cosmological maps. As we look forward to the completion of current surveys and more ambitious future surveys coming online, these explorations would allow us to take a new look at the invisible landscape of our Universe.
Thursday lunch discussions