During the academic year, the Department hosts a weekly colloquium series which features speakers from both academia and industry. This semester (Fall 2020) the colloquia take place on Thursdays from 3:05-4:20 pm on Zoom. Please contact the colloquium coordinator, Milan Mijic (mmijic [at] calstatela [dot] edu), for the link.
This week's colloquium
Sarah Blunt, Caltech,
"The Orbits of Cold Jupiters"
Thursday, Oct. 22, 3:05 pm
Over the past 30 years, thousands of exoplanets have been discovered orbiting other stars. In this talk, I'll highlight the difficulties associated with studying a particular population, the cold Jupiters, along with the exciting scientific results achieved by overcoming some of these challenges and modeling the orbits of planets in this population. I'll discuss constraints on the angular momentum budget of newborn planetary systems, the long-term dynamical stability of systems with multiple giant planets, interactions between giant planets and the circumstellar disks from which they formed, the oddball eccentric giant HR 5183 b, and how all of these results fit into an emerging empirical picture of dynamically quiet formation. Finally, I'll present ongoing efforts to model cold Jupiter orbits ever more precisely, highlighting the recent work of CSULA alum Roberto Tejada and current student Sofia Covarrubias.
Oct. 29: Yohannes Shiferaw, CSU Northridge, "Stochasticity, nonlinear dynamics, and waves: the mechanisms that underlie cardiac arrhythmias"
The mechanisms that cause cardiac arrhythmias are generally not understood. In some cases the cause can be traced to a genetic defect which affects proteins at the molecular level. However, the problem involves a vast range of length and times scales and it is not understood how these molecular scale defects translate to an arrhythmia at the whole heart level. In this talk I give an overview of our recent work applying multi-scale modeling to understand the fundamental mechanisms relating protein dysfunction to a whole heart arrhythmia. I will show how we develop computational models at the key spatial scales, and how these are linked to identify key instabilities which are the root cause of the arrhythmia. I also highlight the important role of stochasticity, nonlinear dynamics, and excitable wave dynamic. This work highlights the importance of the crucial insights provided by physics and mathematics to understand complex problems of medical significance.
Nov. 5: Brian Shuve, Harvey Mudd College, "Illuminating Hidden particles at High-Energy Colliders"
More than 80% of matter in the universe is dark: it doesn’t interact with light, and it’s not made of any of the known elementary particles. What could this dark matter be? Looking at the known particles, also known as the Standard Model, we see many different forces (strong, weak, electromagnetic) and particles (quarks, electrons, neutrinos). If dark matter is anything like the Standard Model building blocks we are made of, there may be an abundance of hidden forces and particles out there for us to discover. I will give an overview of some recent theories of what these dark matter particles and forces could be, and talk about how we hope to discover evidence for these particles at high-energy colliders such as the Large Hadron Collider at CERN.
Nov. 12: Laura Grego, Global Security Program at the Union of Concerned Scientists, "The Growing Danger of Nuclear Weapons (and how physicists can help reduce it)"
While nuclear weapons might sound like Cold War relics, in truth the immense risks they pose to all humanity are still very much with us. In fact, trends indicate the risks may be growing with the abandonment of arms control agreements and the development of new types of strategic weapons. Physicists have historically constructively engaged policymakers and their communities to help reduce nuclear dangers. This talk will explain the current nuclear crisis, provide feasible remedies, and introduce a new project sponsored by the American Physical Society to help physicists once again get involved.
Nov. 19: Michael Peterson, CSU Long Beach, "Keeping it real: theoretically searching for instrinsic topologically ordered phases in realistic systems"
Intrinsic topologically ordered phases continue to motivate and fascinate both theoretical and experimental condensed matter physics. Some topologically ordered phases theoretically support non-abelian quasiparticle excitations. These exotic excitations, while fundamentally interesting physically, have been proposed as building blocks for a fault tolerant quantum computer. Thus, there is great interest in finding realistic experimental platforms which support these topological phases. In this talk I will discuss recent theoretical work regarding our search for realistic systems in the fractional quantum Hall effect and low-dimensional spin systems that are likely to support exotic quasiparticle excitations.
Dec. 3: Vera Glusevic, USC, "Dark Matter throughout Cosmic History"
Dark matter constitutes 85% of matter content in the Universe, but its physical nature remains unknown and requires new physics to explain. I will review the status of cosmological searches for dark matter interactions, summarizing the best current limits on scattering of light particle candidates with protons derived from the cosmic-microwave-background anisotropy measurements. I will then present stringent new bounds on the same physics, inferred recently from the observed abundances of the Milky Way satellite galaxies. I will highlight complementarities between different observations and laboratory searches for dark matter, and discuss the prospects for unveiling the physics of dark matter in the coming decade.
Previous colloquia (2020-21)
Oct. 15: Nathan Strange, JPL, "The Scenic Route to Enceladus"
Oct. 8: Krishna Sigdel, Cal Poly Pomona, "Dynamic structure of P-glycoprotein (P-gp) in membranes via force microscopy"
Oct. 1: Stephanie Wissel, Penn State, "The Quest for the Cosmic Neutrinos at the Highest Energies"
Sep. 24: Mahmoud Hammouri, Cal State LA, "Quasi-two-dimensional electron gas at the interface of Bi2ZnTiO6/SrTiO3"
Sep. 17: Shan-Wen Tsai, UC Riverside, "Proposals for quantum simulating lattice gauge theory models"
Sep. 10: Chantal Nguyen, University of Colorado, "The physics of collective animal behavior: aggregation, navigation, and communication"
Sep. 3: Laura Sales, UC Riverside, "Dwarf Galaxies and their Dark Matter Content"
Aug. 27: Greta O’Dea (Bernal group), Lorraine Sandoval and Roberto Tejada (Terebey group), Robert Appleton and Allen Marquez (Jishi group), Charles Metzler-Winslow and Danielle Wilkerson (Nerenberg group), and Miguel Lopez (Aniol group) – Student Research Projects