High Energy Theory Seminar: "Spinning Cosmology"
Andrei Khmelnitsky (ICTP)
We study the signatures left by new light particles with a spin on the primordial cosmological fluctuations. In distinction from the pure de Sitter background, where fields with spin have to be massive enough to…
Condensed Matter Seminar: "A change in stripes for cholesteric shells via anchoring in moderation"
Lisa Tran (University of Pennsylvania)
Chirality, ubiquitous in complex biological systems, can be controlled and quantified in synthetic materials such as cholesteric liquid crystal (CLC) systems. In this work, we study spherical shells of CLC under weak…
High Energy Theory Seminar: "Equivalence Principle in Scalar-tensor Theories"
Lasma Alberte (ICTP)
We study the question of whether the equivalence principle holds for extended objects moving on cosmological backgrounds in modified gravity theories. We do so within the framework of effective field theory of dark…
WIP: "A Cosmic Perspective: Searching for Aliens, Finding Ourselves"
Dr. Jill Tarter (Bernard Oliver Chair for Search for Extra-Terrestrial Intelligence (SETI) Institute)
Are we alone? Humans have been asking this question throughout history. We want to know where we came from, how we fit into the cosmos, and where we are going. We want to know whether there is life beyond the Earth…
Condensed Matter Seminar: "The Structure and Function of Organic-Inorganic Hybrid Perovskites"
Cherie Kagan (University of Pennsylvania)
Organic-inorganic hybrid perovskites represent a class of materials composed of corner sharing metal halide octahedra charge balanced by organic cations. The hybrid perovskites may be tailored in their composition…
Astro Seminar: "Stellar Spin-orbit Misalignment"
Joshua Winn (Princeton)
In the Solar system, the planets follow orbits that are aligned with the Sun’s equatorial plane to within a few degrees. But what about planets around other stars? Many techniques are now available to measure the…
High Energy Theory Seminar: "Topological Sectors, Supersymmetric Localization, and Holography"
Silviu Pufu (Princeton University)
*Special* HET Seminar: "Many-body Localization: Breakdown of Thermalization in Quantum Matter"
Arijeet Pal (Oxford)
Until recently interacting many-particle systems governed by the laws of quantum mechanics were assumed to eventually reach thermal equilibrium, being described by equilibrium statistical physics. Rapid developments…
Condensed Matter Seminar: "Magnetism in Amorphous Alloys"
Frances Hellman (University of California at Berkeley)
Most condensed matter textbooks start by introducing crystal symmetries and the periodic lattice as foundational to the field. Yet, it has long been known that the amorphous structure supports ferromagnetism,…
Astro Seminar: "Fundamental Physics from the Non-linear Universe"
Marcel Schmittfull (IAS)
The cosmology community is running a large program of galaxy surveys over the next 10 years. Our goal is to map out the properties of dark energy as a function of time, measure the sum of neutrino masses, and study…