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
Dec. 8, 2015 Andrew Wetzel (’05), Caltech
Simulating the Universe, one galaxy at a time

Within the cosmic web, galaxies form as baryonic gas flows along cosmic filaments into dark-matter halos. This gas fuels the formation of stars within galaxies, while the resultant feedback from stars and supernovae drive strong outflows of gas from galaxies. Understanding the physics of this complex interplay between cosmic inflows and feedback-driven outflows is one of the most significant questions …

Oct. 27, 2015 Michael J. Martin (’06), Caltech
Nanophotonics and ultracold atoms: a new set of tools for controlling atom-light interactions

Nano- and micro-scale optical systems, with feature sizes comparable to the wavelength of light, represent a powerful way to control the properties of optical fields. For example, photonic crystals (periodically patterned dielectrics) possess optical properties linked to their underlying geometry that can significantly depart from those of the dielectric material from which they are patterned. In the field of quantum …

Oct. 6, 2015 John Belcher, Massachusetts Institute of Technology
Voyager 1 in the Interstellar Medium: What are we Seeing Out There?

The Voyager spacecraft were launched in the Fall of 1977, 38 years ago. After a “grand tour” of the outer planets, ending with Voyager 2 at Neptune in 1989, the spacecraft have continued outward toward interstellar space, continuing to return data about the particle and field environment of the distant solar and interstellar medium. Voyager 1 is farthest from the …

Sept. 22, 2015 HMC Physics Majors, Harvey Mudd College
Off-campus summer research in physics

The following students will describe how they identified summer research positions, what they worked on, and what their REU program was like beyond the particular project they worked on:

  • Matthew Dannenberg
  • Sabine Fontaine
  • Nathaniel Leslie
  • Morgan Mastrovich
  • Colin Okasaki
  • Jonathan Ueki
  • Shanel Wu
April 28, 2015 Jim Enstrom (’65), University of California at Los Angeles
This talk has been cancelled

I will describe how I have used my 1965 HMC B.S. in physics to rise, at least briefly, to the top of two vastly different branches of science: first, a very hard science—experimental elementary particle physics at Stanford University, and second, a very soft science—environmental epidemiology at UCLA.

My talk will explain the important roles that HMC, creative thinking, …

April 14, 2015 Katharina Gillen, Cal Poly Pomona
Quantum Computing With a 2D Array of Movable Atom Traps Formed by Pinholes

Quantum computers have the potential to perform certain tasks much faster than even the most powerful supercomputers through the use of superposition and entanglement, two of the unusual features of quantum mechanics. Despite the fact that many different systems are being explored as candidates, no fully functioning quantum computer has been built yet. One approach is quantum computing using (neutral) …

March 31, 2015 Emma Wollman, Caltech
Evidence of quantum squeezing of motion in a mechanical resonator

Quantum mechanics places limits on the minimum energy of a harmonic oscillator via the ever-present “zero-point” fluctuations of the quantum ground state. Through squeezing, however, it is possible to decrease the noise of a single motional quadrature below the zero-point level as long as noise is added to the orthogonal quadrature. While squeezing below the quantum noise level was achieved …

March 10, 2015 Jason Rhodes (’94), Jet Propulsion Laboratory
Exploring the Dark Sector with Euclid and WFIRST

The past decade has seen the emergence of the so-called “concordance model” of cosmology. In this model, the Universe started about 13.7 billion years ago in a Big Bang and is now dominated by dark matter and dark energy. Together this poorly understood “dark sector” makes up about 95% of the Universe, but the nature of these phenomena remains elusive. …

March 3, 2015 Jason Gallicchio, University of Chicago
A Long Winter: Cosmic Microwave Background Polarization with the South Pole Telescope

The South Pole Telescope is the largest Cosmic Microwave Background telescope in the world. Its high-resolution maps were the first to show evidence of so-called B-mode polarization due to gravitational lensing by intervening matter. Wider maps are now shedding light on the larger-sized B-modes generated by gravity waves created a right after the big bang. I will discuss the technology …

Feb. 24, 2015 Luis A. Orozco, University of Maryland
Optical Nanofibers

Nanofibers are a versatile platform for applied and fundamental studies. I will present our work starting with the production and characterization of the fibers. Then I will show that Rayleigh scattering from modes on the nanofiber gives information about the diameter with sub-micron resolution. We are using nanofibers for quantum optics and quantum information studies. We use the evanescent fields …

Feb. 10, 2015 Colin V. Parker (’06), James Franck Institute and Department of Physics, The University of Chicago
Dispersion Engineering with Cold Atoms: Ferromagnetism, Rotons, and Beyond

For classical or quantum Hamiltonians, one typically writes the kinetic energy, or dispersion, as a simple parabola for small momentum. However, particles traveling in certain periodic potentials (i.e. lattices) may have a dispersion that is minimized at multiple values of momentum or that depends upon the fourth power of momentum, preventing such a simple description. My collaborators and I have …

Feb. 3, 2015 Andrew Grier (’04), Columbia University
Extreme Quantum Mechanics: Quantum simulation of many-body systems using ultracold atomic gases

What happens when the strength of interactions between atoms is turned up to infinity? What about when one mixes two types of superfluids? In this talk, we will explore how ultracold atomic gases are used to create and probe these types of systems. I will discuss our recent success producing and studying extreme quantum states in ultracold lithium gases including …

Jan. 27, 2015 Ben Olsen, Rice University
Ultracold Atomic Superfluids in 3D, 1D, and in Between

Atomic gases cooled to nanokelvin temperatures can be used to study the physics governing exotic many-body quantum systems, some of which are too complicated for computer simulation. Several many-body systems, including superconductors and neutron stars, exhibit frictionless flow, or superfluidity. We experimentally probe the fermion pairing that leads to superfluidity using laser-trapped clouds of ultracold lithium atoms in two spin …

Nov. 18, 2014 Clifford Johnson, University of Southern California
Black Holes and Holographic Heat Engines

New work has shown how to complete the correspondence between the physics of black holes and the laws of thermodynamics by incorporating volume and pressure into the formalism. This results in a change in the interpretation of the black hole's mass, and may give a new handle on understanding aspects of theories of gravity with non-vanishing cosmological constant. This subject …

Nov. 4, 2014 Karen E. Daniels, North Carolina State University
Playing with Sand: Complex Behaviors from a Simple Material

Granular materials are integral to many parts of our daily lives, from the coffee beans that fuel our mornings to the coal that fuels our power plants. At first glance, these materials might appear simple: macroscopic dry, cohesionless particles which interact only by contact forces. However, they represent a complicated phase of matter neither wholly solid nor wholly liquid: a …