The electron is still round

Today is the publication of the latest result from the experiment that I work on at Harvard, the Advanced Cold Molecule Electron Electric Dipole Moment, or ACME EDM (here is a link to read the paper in entirety). In this experiment, we seek to look for an asymmetry in the electron’s shape. What does that exactly mean … Continue reading “The electron is still round”

Introducing the ACME EDM Experiment

This is a new, streamlined introduction to the ACME EDM experiment, which is an experiment I’m working on as part of my PhD in physics at Harvard University. The following are strictly my own personal views and should NOT be taken as representative of the ACME collaboration. I am only writing this as part of my … Continue reading “Introducing the ACME EDM Experiment”

A Brief History of the Electron’s Shape – Part 5: The Age of Molecules

In our last post, we saw how the potential of atoms had been pushed to an incredible limit by the work of Commins and his group at Berkeley. Now, the 21st century had arrived, and technology was ready to start utilizing the power of molecules, which are nature’s built-in mini-laboratories for the electron. Nature’s Small … Continue reading “A Brief History of the Electron’s Shape – Part 5: The Age of Molecules”

A Brief History of the Electron’s Shape – Part 4: The Ultimate Atomic Beam Experiment

Eugene Commins was one of the most influential atomic physicists of the latter half of the 20th century, not just through his experimental results, which were first-rate (including being one of the first to observe atomic parity violation), but most especially through his legacy of mentorship and teaching. His group at UC Berkeley produced a … Continue reading “A Brief History of the Electron’s Shape – Part 4: The Ultimate Atomic Beam Experiment”

A Brief History of the Electron’s Shape – Part 3: How My Small College Measured the Electron’s Shape

When we left off last time, we were in the middle of a drought: over two decades of no improvement in the upper limit of the electron EDM from that found by the last of the cesium beam experiments in 1968: This was not a bad number at all. In fact, using the classical electron … Continue reading “A Brief History of the Electron’s Shape – Part 3: How My Small College Measured the Electron’s Shape”

A Brief History of the Electron’s Shape – Part 2: The First “Golden Age”

Last week, we talked about how the pioneering papers in the 1950s and 60s of Purcell, Ramsey, and Sandars started off the decades-long search for imperfection in the electron’s shape, or the electron electric dipole moment (eEDM). This week, we’re going to cover some of the early beam experiments dedicated to measuring the electron EDM. … Continue reading “A Brief History of the Electron’s Shape – Part 2: The First “Golden Age””

A Brief History of the Electron’s Shape – Part 1: Origins

As I’ve shared in a series of blog posts, I currently work on an experiment measuring the electric dipole moment (or EDM) of the electron. Colloquially, we like to call it the “shape” of the electron. (To be a little bit more accurate, it’s really the shape of the electric field produced by the electron.) … Continue reading “A Brief History of the Electron’s Shape – Part 1: Origins”

How Tabletop Experiments Could be the Future of Particle Physics

Just this week an article in Nature was published featuring the new activities that the Gabrielse lab (where I work) is starting up at the newly-found Center for Fundamental Physics at Northwestern. In particular, the article highlights the growing importance of relatively small-scale “tabletop” experiments like ACME to probe for new physics beyond the Standard … Continue reading “How Tabletop Experiments Could be the Future of Particle Physics”

Guide to the ACME EDM Experiment: Why CP Violation Might Explain Everything About the Universe

Why should we care about the existence of the electron electric dipole moment (EDM)? In a previous post, we established that the existence of an electron EDM would imply a violation of a symmetry in physics called CP-symmetry, or CP violation (CPV). But it isn’t clear why CPV has any importance beyond being something interesting … Continue reading “Guide to the ACME EDM Experiment: Why CP Violation Might Explain Everything About the Universe”

Guide to the ACME EDM Experiment: Symmetries in Physics

In this series so far, we’ve discussed a lot about the physics of the ACME EDM experiment: the atomic physics methods we use to look for a small asymmetry in the electron’s charge distribution. However, we’ve never tackled the big question directly: why does the electron’s charge distribution matter at all? The precision achieved on the … Continue reading “Guide to the ACME EDM Experiment: Symmetries in Physics”