Physics Colloquium – Gregory Rudnick

Lapham 160 3209 N. Maryland Ave., Milwaukee, WI, United States

Gregory Rudnick, University of Kansas

The Life Cycle of Galaxies in Clusters Over 10 Billion Years

Galaxies live in a range of environments, characterized by their volume density. For example, the densest regions of the Universe are in galaxy clusters, which contain hundreds to thousands of galaxies all in pseudo gravitational virial equilibrium. These dense environments can in turn alter the properties of the galaxies themselves in striking ways via a variety of gravitational and hydrodynamic processes. The result of these processes alter galaxy shapes, their internal dynamics, and shuts off the formation of new stars.

Physics Colloquium – Wynn Ho

Lapham 160 3209 N. Maryland Ave., Milwaukee, WI, United States

Wynn Ho, Haverford College

The Impact of Pulsar Glitches and NICER on Gravitational Wave Searches

Pulsars are the rotating remnant of massive stars and are unique probes of dense matter physics. They are famous for having very precisely measured spin rates, and this spin evolves extremely regularly for most pulsars. However, young pulsars can occasionally undergo sudden spin changes, known as glitches.

Physics PhD Colloquium – Deep Chatterjee

Lapham 160 3209 N. Maryland Ave., Milwaukee, WI, United States

Deep Chatterjee, University of Wisconsin-Milwaukee PhD Candidate

Title and abstract TBA

Physics Colloquium – Dr. Morgan Lynch

KIRC 1150 3135 N. Maryland Ave., Milwaukee, WI, United States

Dr. Morgan Lynch, Technion – Israel Institute of Technology

A Brief History of Quantum Field Theory in Curved Spacetime

The incorporation of classical general relativity into the framework of quantum field theory yielded a rather surprising result -- thermodynamic particle production. In short, for fundamental deformations in the structure of spacetime, quantum mechanics necessitates the creation of thermalized particles from the vacuum. One such phenomenon, known as the Unruh effect, causes empty space to effervesce a thermal bath of particles when viewed by an observer undergoing uniformly accelerated motion.

In this presentation, we will review the timeline of conceptual discoveries which led to broad classes of these intriguing thermodynamic phenomena. Beginning with the original discovery of particles created by the expansion of the universe, we will cover a brief history of quantum field theory in curved spacetime, culminating in the first experimental observation of the Unruh effect, and other aspects of acceleration-induced thermality, in high energy channeling radiation.

Physics Colloquium – Mark Williamsen

KIRC 1150 3135 N. Maryland Ave., Milwaukee, WI, United States

Mark Williamsen, Quantum Design, Inc

Applications of AC Bridges in Cryogenic Measurements

AC (alternating current) bridges have proven to be useful in making precise measurements at low temperature, including thermometry as well as length change with respect to either thermal expansion (dilatometry) or applied magnetic field (magnetostriction). Techniques now in use allow one leg of the bridge to be placed at the cryogenic sample site while the other legs remain at room temperature, with the intervening temperature gradient being imposed along a length of coaxial cable.

Physics Colloquium – Daniel Vrinceanu

KIRC 1150 3135 N. Maryland Ave., Milwaukee, WI, United States

Radiative Cascade in Rydberg Atoms

This talk is an introduction to the physics of Rydberg atoms. The two complementary flavors of Rydberg atoms, high and low angular momentum states, have contrasting properties as they relate to the correspondence principle that bridges classical behavior to quantum mechanics. Dynamic symmetries allow a unified point of view to investigate this correspondence. Highly excited atoms dissipate their energy in different ways depending on their initial angular momentum: low angular momentum states make transitions in large energy increments, quickly approaching the ground state, while high angular momentum states make small steps, slowly spiraling towards lower states.

Event Series Physics Colloquium – Open

Physics Colloquium – Pierre-Alexandre Gourdain

KIRC 1150 3135 N. Maryland Ave., Milwaukee, WI, United States

The Impact of Electron Physics in High Energy Density Plasmas

The study of high energy density plasmas (HEDP) allows researchers to study the impact of microscopic phenomena on macroscopic scales by using plasmas dense enough to be probed by high energy photons (i.e. visible, UV, X-ray). This probe allows us to use readily available detectors to make precise, two-dimensional measurements of the electron density and infer the electron flow speed and magnetic field.

Physics Colloquium – Dr. Horia Petrache

Dr. Horia Petrach, Department of Physics, Indiana & Purdue Universities

Interactions of Neuromodulators with Model Lipid Membranes

Neurotransmitters and neuromodulators typically function by binding to specialized receptors in neuronal membranes. In this work, we study two different neurotransmitters that also function as neuromodulators, namely dopamine (DA) and adenosine triphosphate (ATP). Dopamine is best known as the feel-pleasure hormone while ATP is best known for being the source of energy in the cell.