Events Daily

Wednesday, September 12, 2018

The EFThedron
Yu-tin Huang, National Taiwan University
Event Type: HEP Seminar
Time: 2:00 PM - 3:30 PM
Location: 726 Broadway, 940, CCPP Seminar
Description: It has long been known that UV unitarity imposes model independent constraint in the IR in the form of positivity conditions of certain higher dimension operators. This leads to many important consequences on consistent QFTs, including the a-theorem in 4D. In this talk, I will show that these positivity constraints are merely the ``tip of the iceberg", where there's an inifinte number of non-linear qualities constraining the couplings, given by the direct product of positive geometries. This geometry cuts out the space of consistent EFTs.

Modeling the Non-Linear Universe using Cosmological Simulations
Joe DeRose, Stanford
Event Type: Informal Astro Talk
Time: 3:30 PM - 4:00 PM
Location: 726 Broadway, 940, CCPP Seminar
Description: Current and upcoming cosmological surveys are turning their eyes towards the late time universe in an attempt to answer fundamental questions about the structure of our world and the physical laws that govern it. Given the non-linear nature of the observables studied by these surveys, perturbative modeling approaches have limited faculty. Thus, non-perturbative simulation approaches are necessary in order to connect theory with observation and wring the most information out of the deluge of data that will be collected in the coming years. In this talk I will discuss a number of efforts I am involved with to interpret data using simulations within the Dark Energy Survey, focusing on their use in our Y1 analyses, and how we are extending this for upcoming analyses. I will also briefly discuss more forward looking efforts to build emulators for galaxy survey observables that promise to unlock the information contained in highly non-linear observables, such as the halo mass function, redshift-space distortions and small scale projected clustering and galaxy-galaxy lensing.

Astro Ph
Event Type: Astro Ph
Time: 4:00 PM - 4:30 PM
Location: 726 Broadway, 902, Lg Conf