The Frustrating Search for New Physics – An article I wrote for Harvard’s Science in the News, a popular science blog. Here I give an overview of the Standard Model of particle physics, and two major problems with it that drive our research for new physics. Yet in the last few decades we have failed to find anything beyond the SM.
Why Dark Matter and not MOND? – An article originally written for science-religion forum Peaceful Science, explaining why in light of the evidence we have, the hypothesis of dark matter can seem much more reasonable than modifying the laws of gravity.
Guide to the ACME EDM Experiment
An series in which I introduce the electron EDM experiment I am working on at Harvard bit by bit, trying as much as possible to avoid technical jargon and making an explanation understandable by a general audience with only high school-level mathematics. The official website of the ACME experiment is here.
The most recent introduction to the experiment is this page which summarizes my thesis. Introducing the ACME EDM Experiment is a general introduction which explains the gist of what we are doing in ACME by measuring the roundness of the electron. It describes the apparatus for the ACME II measurement which concluded in 2018, but the basic principles remain the same for ACME III. You can also read The electron is still round, a quick series of answers to common questions about the recent 2018 ACME II result.
For an explanation for why the roundness of the electron matters at all, read Why CP Violation Might Explain Everything About the Universe explaining how the electron EDM relates to the problem of baryon asymmetry.
For a more detailed outline of how the experiment works, read A Simple Overview. This includes an explanation for spin precession, the core physical process which allows us to probe the effects of the deformation of the electron.
The following articles are longer, but are useful to fully understand the physics and methods present in the experiment.
- Atomic Structure A tutorial on how energy is “stored” in atoms and molecules. This is the energy we measure carefully when doing the spin precession.
- Differential Measurements to the Extreme The concept of a differential measurement, which defines the fundamental operation of the ACME experiment.
- Symmetries in Physics An explanation of C, P, and T symmetries and how the electron EDM violates CP symmetry, allowing it to be used as a probe for CP violation, which relates to it being able to solve the baryon asymmetry problem.
A Brief History of the Electron’s Shape
In this series, which is quite like no other, you will see me go through 60 years of measurements of the electron electric dipole moment, from 1965 to the present day! I guarantee that there is nothing quite like this on the Web.
- Part 1: Origins. Learn about the three physicists who first made us realize the importance of the electron’s shape: Purcell, Ramsey, and Sandars.
- Part 2: The First “Golden Age”. Sandars and his competitors usher in a rush of activity measuring the electron EDM in the 60s by developing the cesium beam technique.
- Part 3: How My Small College Measured the Electron’s Shape. After a long two-decade drought, a small college in Western Massachusetts resurrects the subject by achieving a massive improvement.
- Part 4: The Ultimate Atomic Beam Experiment. Eugene Commins at Berkeley brings the art of atomic beams to its zenith.
- Part 5: The Age of Molecules. The next breakthrough in measurement of EDMs comes from upgrading atoms into molecules: tiny natural laboratories that allow us to apply electric fields billions of times larger than anything man-made.