Ed Groth's Home Page

EJG photo Edward J. Groth
Room 264, Jadwin Hall
Physics Department
Princeton University
Princeton, NJ 08544
Phone: 609-258-4361
Fax: 609-258-6853

Quick link to my photo albums and to my newer personal pages.

Update: October 30, 2016, 6:25 am. A beautiful fall day! The ride is on! Cool to start (60 F), warming during the day (75 F). A chance of rain later, but looks like we can get the ride in. We'll just keep an eye on the weather and turn around early if necessary.

How about a bike ride to check out the fall colors? Saturday, October 30, 2016 (no rain date) 8:00 am (leaving Princeton at 7:30 am).

Forty-five mile round trip from Washington's Crossing to Frenchtown and back on the Delaware and Raritan Feeder Canal Towpath/Rail Trail with lunch in Lambertville/New Hope on the way back.

Click on the link for more info!

Teaching: In the recent past, I've taught the advanced Sophomore mechanics course, Physics 205; the Junior E & M course, Physics 304; and the introductory physics course, Physics 103. In the Spring of 2000, I managed the labs for Physics 102. In the Fall of 2000, I taught the first term of the three term introductory course, Physics 107, for the first time. In the Spring of 2001, I taught advanced E&M for freshmen for the first time, Physics 106. In the Fall of 2001, I taught the third term of the three term introductory course, Physics 109, for the first time. In the spring of 2002, I gave the lectures in Physics 102 for the first time. In the fall of 2002, I taught Thermal Physics, Physics 301 for the fourth time after a two year break. In the spring of 2003, E&M for freshman, Physics 104. In the fall of 2003, it's Thermal Physics, Physics 301 again. In the spring of 2004, FRS 142, a freshman seminar: "Where's Waldo? The Science and Application of GPS." In the fall of 2004, Thermal Physics, Physics 301. In the spring of 2005, I taught a section of Physics 102, premedical physics, and in the fall of 2005, it was Thermal Physics, Physics 301. For the spring of 2006, it was the freshman seminar on GPS again, FRS 144 (the number changed). Fall 2006 was Physics 105, Introductory physics for well prepared undergraduates. In the spring of 2007, "Where's Waldo" is back again, FRS 142. Fall, 2007, it's quantum mechanics for graduate students, PHY 505. In the spring of 2008, I taught a section of Physics 104, the calculus based introductory course and in Fall, 2008, it's quantum mechanics for graduate students again PHY 505. In the spring of 2009, I served as lab manager and taught a section of Physics 104, the calculus based introductory course and in Fall, 2009, it's quantum mechanics for graduate students again PHY 505. In spring 2010, I was again lab manager and a section instructor for Physics 104. For fall 2010, it was quantum mechanics again, PHY 505. Yet another tour as lab manager and section instructor for Physics 104 in spring 2011, and more introductory quantum mechanics in the fall, PHY 505. In spring, 2012, a section of Physics 104 and introductory quantum mechanics in the fall, PHY 505. In the fall of 2013, a section of Physics 103, the first semester of the introductory physics course.

Retirement: In the spring of 2012, I signed a retirement agreement with the university. I will continue half time through academic year 2014-15 and then transfer to emeritus status.

Research: My research interests are in astrophysics including IR astronomy, pulsar timing, cosmology, including the study of faint galaxies and clusters, and the development of the Hubble Space Telescope. Lately, I've begun to follow research in exoplanets.

Advising: If you're one of my advisees, my regular office hours are 2-4 Wednesday afternoons, but I'm often available at other times. Send an email to make an appointment. For the spring term and fall term course selection appointments, we'll use the on-line appointment system.

My CV.
My Publication List.
My Mini Bio.

The Hubble Space Telescope is a superb instrument today, but it wasn't always so:


This image illustrates a comparison of a ground based image, an HST image before the spherical aberration was fixed, and an image after the fix - all on the same star field at the same scale. You can see more and fainter stars with the fixed HST for two reasons: first, the star images are smaller, so there's less overlap; second, the smaller images can be detected against a smaller patch of background light. (Even above the atmosphere, the sky isn't completely dark! Scattering of sunlight by dust particles in the solar system - the Zodiacal light - causes a diffuse brightness which is 23 magnitudes per square arcsecond at the darkest spots, close to the ecliptic poles.)

We had to work pretty hard to get from the middle image to the right image!