Colloquium

Junior and senior physics majors attend our biweekly colloquium series, held on Tuesday afternoons at 4:30 pm in Shanahan B460. The talks are open to all students and to the public, and are frequently attended by scientists from the other Claremont Colleges, Cal Poly Pomona, and others. The series features speakers from a broad range of institutions and fields of physics.
HMC Physics Colloquium shot
April 25, 2017 Rita Kalra, Space X
The Challenges of Space Weather and Radiation Environments in Aerospace

Space radiation from high-energy particles is a field that is of increasing importance in this dawning space age. Extreme space weather events are responsible for a variety of problems including satellite failures and radio blackouts, and also have the potential for catastrophic impacts on Earth such as a near-global loss of the power grid. Additionally, radiation protection for astronauts is ...

April 18, 2017 Hendrik Oldag, SLAC
Ultrafast and Very Small: Discover Nanoscale Magnetism With Picosecond Time Resolution Using X-Rays

Today’s magnetic device technology is based on complex magnetic alloys or multilayers that are patterned at the nanoscale and operate at gigahertz frequencies. To better understand the behavior of such devices one needs an experimental approach that is capable of detecting magnetization with nanometer and picosecond sensitivity. In addition, since devices contain different magnetic elements, a technique is needed that ...

April 4, 2017 Ivan Deutsch, University of New Mexico
Breaking Heisenberg: Controlling the Quantum World

The quantum information revolution has taught us that quantum mechanics is not a paler version of its classical counterpart, hindered by intrinsic uncertainty and random measurement outcomes. Au contraire! A machine whose operation takes full advantage of the laws of quantum mechanics has information processing capabilities well beyond those that are restricted to essentially classical laws. To harness this power ...

March 21, 2017 Siddarth Parameswaran, University of California at Irvine
Topology and the Phases of Condensed Matter

The 2016 Nobel Prize in Physics was awarded to David Thouless, Duncan Haldane, and Michael Kosterlitz "for theoretical discoveries of topological phase transitions and topological phases of matter." I will review the discoveries they made and explain how they have changed our understanding of critical phenomena in low dimensions and the phases of quantum matter.

March 7, 2017 Andrew Howard, Caltech
Earth-size Exoplanets

Earth-size exoplanets and their slightly larger ‘super-Earth’ cousins are the most abundant planets orbiting close to Sun-like stars. These planets have diverse physical compositions, unusual atmospheres, and poorly understood origins. My talk will trace the discovery and early characterization of these small worlds through Doppler and transit surveys, and look forward to future discoveries with instruments such as the Keck ...

Feb. 21, 2017 Jason Gallicchio, Harvey Mudd College
Cosmic Bell Test: Measurement Settings from Milky Way Stars

Bell’s theorem states that some predictions of quantum mechanics cannot be reproduced by a local-realist theory. That conflict is expressed by Bell’s inequality, which is usually derived under the assumption that there are no statistical correlations between the choices of measurement settings and anything else that can causally affect the measurement outcomes. In previous experiments, this “freedom of choice” was ...

Oct. 25, 2016 Paul SanGiorgio '01, Illumina
Life After Physics, or How I Learned to Stop Worrying and Love Systems Engineering

Traditional job opportunities for physicists in research and academia are becoming harder and harder to find and facing this new reality, physics graduates often find themselves making difficult choices about what to do with their lives. One little-talked-about and oft-overlooked opportunity for physics graduates is the field of systems engineering. But, what is systems engineering? Why are physicists uniquely suited ...

April 26, 2016 Matt Evans (’96), Massachusetts Institute of Technology
Gravitational Wave Detection With Advanced LIGO

The Laser Interferometer Gravitational-wave Observatory (LIGO) recently made the first direct detection of gravitational waves; minute distortions in space-time caused by cataclysmic events far away in the universe. I will talk about the source of the signal we detected, the physics behind the detectors, and prospects for the future of this emerging field.

April 5, 2016 Jim Fuller, Caltech
Saturn Ring Seismology

The rich dynamics of Saturn's rings offer a unique opportunity to study the internal structure of the planet. Like the Sun, Saturn continuously pulsates at low amplitudes due to convective motions in its interior. Although these pulsations are too small to be directly detected, their gravitational interaction with particles in the rings creates density waves at Lindblad resonances in the ...

March 22, 2016 Janice Hudgings, Pomona College
Photonic Device Applications of Modulated-Reflectance Imaging

We have demonstrated a high-resolution (250nm, 10mK), non-contact modulated reflectance imaging technique which, in combination with an energy balance model, can be used for spatially resolved thermal, optical, and electrical metrology of optoelectronic devices. Applications include optical testing of photonic integrated circuits, current spreading and thermal management in light emitting diodes, thermal lensing in vertical cavity surface emitting lasers, and ...

March 8, 2016 Jason Hogan (’03), Stanford University
Tests of gravity and quantum mechanics using atom interferometry

Precision atom interferometry is poised to become a powerful tool for discovery in fundamental physics. Towards this end, I will describe recent, record-breaking atom interferometry experiments performed in a 10-meter drop tower that demonstrate long-lived quantum superposition states with macroscopic spatial separations. The potential of this type of sensor is only beginning to be realized, and the ongoing march toward ...

Feb. 23, 2016 Marissa Giustina, Institute for Quantum Optics and Quantum Information — Vienna
Significant-Loophole-Free Test of Local Realism With Entangled Photons

Local realism is the worldview in which physical properties of objects exist independently of measurement and where physical influences cannot travel faster than the speed of light. Bell’s theorem states that this worldview is incompatible with the predictions of quantum mechanics, as is expressed in Bell’s inequalities. Previous experiments convincingly supported the quantum predictions. Yet, every experiment requires assumptions that ...

Feb. 9, 2016 Candidate C, Harvey Mudd College
Games, Electrical Networks, and Quantum Algorithms
Quantum computers exploit the quantum nature of physical systems to perform computations. While we have yet to build a large-scale quantum computer, we can prove that such devices would have an advantage over standard computers for some problems. However, there are still many tasks for which we don't have a good understanding of the performance of quantum computers. For ...
Feb. 2, 2016 Candidate B, Harvey Mudd College
Illuminating the Dark Universe with Particle Colliders

The stars and gases observed in our galaxy and beyond comprise only 15% of the total matter in the universe; the remainder consists of dark matter, so called because it does not emit, reflect, or absorb light. Because the identity of dark matter and the forces it experiences are currently unknown, discovering the physics behind it remains one of the ...

Jan. 26, 2016 Candidate A, Harvey Mudd College
Multi-Scale Studies of the Physics of Earthquakes

Earthquake faults are complex systems that span a huge range of length and time scales. These scale-rich systems are challenging to model, as each scale is itself a complex system that depends on the dynamics occurring at the other scales. Because the largest, damaging earthquakes are rare, estimates of risk based on historical event occurrence is highly uncertain, and physics-based ...