Weekly Colloquium

Most weeks during the semester, we host a scholar for a one-day visit. The visit culminates with a public talk on a topic of contemporary physics or astronomy. Students are welcome to these talks, and seniors are required to attend at least nine over the course of a year. Near the end of each semester, honors thesis students give public lectures on their work.  We gather before the talks for tea, coffee, and cookies at 3:45, Ground Lobby of Science Center followed by the talk at 4:00 pm in A011.

Our Astronomy program is part of the Five College Astronomy Department, which hosts its own colloquium series Thursdays at 3:45 pm at UMass in LGRT 1033. 

  • If you would like to be mailed seminar announcements, please send an email to physics@amherst.edu.
  • Contact colloquium organizer Alice Simmoneau (asimmoneau@amherst.edu) with any questions about colloquia.

Tue, Oct 22, 2019

Brian Daly, Vassar: “Picosecond Laser Ultrasonics: A Sound Way to Study Nanostructures”

Ultrafast lasers produce pulses of light at extremely regular intervals (about 13 nanoseconds apart) that are less than a picosecond in duration. These lasers allow us to study very fast phenomena in crystals and solid nanostructures. The work that my group at Vassar does involves using these lasers to generate and detect ultrasound that is roughly 1,000 times higher in frequency than traditional medical or industrial ultrasound. Since ultrasound can serve as a nondestructive probe of the size or mechanical properties of buried structures, this so called “picosecond ultrasound” should be a great way to study and image the nanoscale structures that form the backbone of all of our modern electronic devices. In this talk, Professor Daly will describe a number of investigations (some very applied, some very fundamental) that we have pursued over the past decade with this optical experiment.

Tue, Oct 29, 2019

Myriam Sarachik, City College of New York: “SURPRISE: Just because you think you’re heading toward a quantum phase transition does not mean you will get there.”

Measurements of the Hall coefficient, resistivity, magnetoresistance, magnetic response, and thermopower in two-dimensional strongly interacting electron systems have established that, contrary to expectations, a metal-insulator transition occurs at a critical electron density nc and a metallic phase exists in 2D. One intriguing mystery has been that, by contrast with the dramatic divergences that have been observed for all other physical properties, the magnetoresistance has exhibited smooth and uneventful behavior approaching and crossing nc. In this talk I will present new data and a different new analysis of the magnetoresistance of the strongly interacting 2D electron system in a silicon MOSFET for a broad range of electron densities. Our surprising results should trigger a re-examination of past work.

Tue, Nov 5, 2019

Michael Lubell, City College of New York: "Navigating the Maze: How Science and Technology Policy Shape America and the World."

Tue, Nov 12, 2019

Eduardo H Da Silva Neto

Tue, Nov 19, 2019

Tue, Dec 3, 2019

Physics/Astronomy Senior Thesis Talks

Tue, Dec 10, 2019

Physics/Astronomy Senior Thesis Talks

Tue, Jan 28, 2020

Information Session for Junior Physics & Astronomy Majors

Information Session for Junior Physics & Astronomy majors beginning at 4:00 p.m. in the Science Center room A013. This will be an informational meeting for all juniors where we will discuss how to go about applying to graduate school and options and procedures for honors thesis projects. Pizza will be served.

Tue, Feb 4, 2020

Tue, Feb 11, 2020