This is one of the coolest physics-related videos I’ve ever seen! Physicist Anders Kaestner took a “neutron x-ray” video of a moka pot (a metal stovetop coffee pot) in action.
I’m thrilled to announce that the Materials Modeling Stack Exchange forum is now in public beta. This means that anyone can browse without having to sign up for sign up for an account and the questions might start showing up in google search results. We’re still actively recruiting more physics-oriented contributors, so I encourage you to check it out.
There are already hundreds of questions and answers on the forum, here’s a couple great discussions you might want to join in on:
- What is a good programming language to learn for materials modeling?
- How to model phase transitions at critical regions in a magnetic system?
- How can very small lattices be sufficient for Quantum Monte Carlo simulations?
- Should I buy a CPU or a GPU for doing calculations?
- In Monte Carlo: does nonequilibrium imply stationary state?
- [Unanswered]: Discrepancy between numerical and transformed derivatives
- What are examples of materials that closely correspond to the Heisenberg model?
APS President Phil Bucksbaum recently wrote a letter with recommendations for how congress can protect science during COVID-19 and ensure a quick recovery afterwards. “The letter’s recommendations include: providing grantees full or partial cost extensions, ensuring the supplemental funding necessary to restart labs and experiments is provided, and substantially increasing REU funding for Summer 2021.”
APS is also organizing a letter-writing campaign to call Congress’s attention to this issue. They’re provided a easy-to-use tool where you can plug in your voting address, sign your letter (and add some of your own thoughts) and they will send it off to your congressperson and senators. It takes less than five minutes and it makes a huge difference. On narrow issues like this, you letter might be the only one your elected official receives!
Some of my colleagues have worked very hard to build up a Materials Modeling Stack Exchange forum, currently in beta. They need more contributors to graduate to a full-fledged forum, so I encourage anyone reading this to join at materials.stackexchange.com (you will have to create an account to join the private beta, but it’s super easy). Much of the discussion is currently on computational chemistry methods like DFT, but the admins are actively seeking more physics content to differentiate themselves from existing Stack Exchange forums.
On Sunday March 29, Philip W. Anderson passed away. Anderson is doubtlessly one of the greatest condensed matter physicists who ever lived.
Anderson made foundational discoveries in localization, high-temperature superconductivity and antiferromagnetism. Indeed, his achievements stretch beyond condensed matter; his work on spontaneous symmetry breaking contributed to development of the Standard Model of particle physics. I’m sure many more competent people will eulogize him (update 2020-05-04 they have), but I wanted share one specific personal connection I have to his work.
For the APS Congressional Visit Day last month, my team visited the DC office of Representative Jim Himes (D-CT-04) to advocate for a number of issues important to science (see previous post). One of our asks was for Rep. Himes to cosponsor the Keep STEM Talent Act. I just heard that Rep. Himes is now a cosponsor! Thanks so much to my CVD team, to Rep. Himes and to the staffer we met with, Jessica Hagens-Jordan!Continue reading
APS Congressional Visit Day 2020
This week, I am in Washington DC for the APS Congressional Visit Day and Annual Leadership Meeting. We started on Wednesday with the Congressional Visit. APS broke us up into teams by region. I’m a Massachusetts voter, so I joined a team of people from Massachusetts and Connecticut. We had six meetings with the offices of Massachusetts Senators Ed Markey and Elizabeth Warren, Connecticut Senators Chris Murphy and Richard Blumenthal along with House Representatives James Himes and Rosa DeLauro.Continue reading
Science is a powerful way of learning how our world works, but that knowledge is useless if ordinary people don’t trust scientists. This lack of trust is at the core of issues like climate change denial and the anti-vaccination movement. Scientific literacy is a huge and complex problem, but I think one cause of this mistrust is how few people know a scientist personally (in fact, one study found that only 4% of Americans could name a living scientist). People tend to trust people they know, so with that in mind I’ve decided to get more involved in science outreach.
I have now visited two local junior high school classrooms through The World in Your Classroom, a program that brings foreigners living in Taiwan into classrooms to meet with Taiwanese students and tell them about their home countries. I’ll describe one of those experiences now.
For the first thirty minutes or so I showed the students some slides talking about where I grew up and how I ended up in Taiwan. In advance, their teacher had sent me a list of questions from the students. They certainly knew a lot more about America than I knew about any foreign country when I was their age, and they weren’t afraid to ask the hard questions. Examples were “Do you support the US maintaining good relations with China?”, “Who did you vote for in the last presidential election?” and “What is your opinion on racism and same-sex marriage?”. Many of their questions asked whether America was friendly to immigrants, to which I said yes. (I imagine news coverage of current events might have inspired those questions). I did not talk extensively about my research, but I did talk about what it’s like to be a scientist and why I like my job. I especially wanted to address the misconception that scientists are all supergeniuses, so I made sure to point out that I was a very poor student when I was their age and I struggled quite a lot in school. They responded really well to this message.
For my trouble I was given a few small gifts, including a box of the best pineapple cakes I’ve had so far (I really need to figure out where those came from). I’m looking forward to meeting more Taiwanese students in the future.
Last Friday, the 26th General Conference on Weights and Measures voted to replace “Le Grand K”, the 129 year old physical prototype of the kilogram, with a new measure based on physical constants. The new definition, which comes in to force next spring, is now fixed by defining the Plank constant as exactly 6.626 070 15 x 10-34 Joule seconds.
The kilogram was the last SI unit based on a physical prototype (which means that until next year, Le Grand K is, by definition, exactly one kilogram). Other prototypes, such as the physical meter, have been long since retired. This redefinition is a triumph of high-precision experimental physics. The problem with physical prototypes for units is that they can change. Le Grand K, for example, has been losing mass, to the tune of about 50 micrograms (5 parts in 100 million), possibly because the identical cylinders it is compared to have gotten dirty from being handled more often.
Farewell Le Grand K! Thank you for your service!
This month’s Physics Today has a great article by Roberto Zenit and Javier Rodríguez-Rodríguez about the physics that governs bubbly drinks. It is relatively nontechnical (aside from a few equations which can be safely ignored).
The fluid mechanics of bubbly drinks
Roberto Zenit and Javier Rodríguez-Rodríguez
Physics Today 71 11 44 (2018)