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mgibbs63

54 karma · joined October 20, 2013

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mgibbs63··on Brookhaven Lab's RHIC concludes 25-year run with final collisions
I think there's a strong argument that the most useful product from collider science is the synchrotron light source. Researchers using collider rings realized that the x-ray synchrotron light these rings emit (an inconvenience to collider physics people) was a fantastic tool for structural biology and materials science. Eventually, they built dedicated electron storage rings that don't do collisions at all - the main goal is producing bright X-ray beams.

Synchrotron light sources have had wide-ranging, concrete impacts on "industrial products" that you probably use every day via studies in: - Drug discovery (Tamiflu and Paxlovid are good examples) - Battery technology (X-ray studies of how/why batteries degrade over time has lead to better designs) - EUV photolithography techniques - Giant Magetoresistance (Important for high capacity spinning-disk hard drives)

mgibbs63··on The Stern-Gerlach Experiment (1967) [video]
I totally agree! I also very much appreciate the amount of time they dedicate to explaining the details of the apparatus. I suspect that very few physics students get any reasonable amount of instruction on experimental techniques these days. I barely did fifteen years ago, and I think things have only gotten worse since then. Without that, the learning curve of working in a research lab can be pretty brutal.

A second benefit I get from spending all that time on the apparatus is kind of paradoxical: those extra details seem like they would distract you from learning and understanding the core concept, but somehow they make things much more approachable. The idealized experiment is slightly too abstract to easily digest.

mgibbs63··on Vera Rubin: Super telescope's giant camera spies broccoli
Fun fact: the guy who made [2] is also the co-author of the first web page hosted in North America.
mgibbs63··on The Vintage Beauty of Soviet Control Rooms (2018)
I agree - many older particle accelerators in the U.S. have/had control rooms that look very similar to these photos (go see the 88-inch cyclotron at Lawrence Berkeley National Lab if you ever get a chance!). I think this is more 'vintage control system aesthetic' than a particularly soviet look.
mgibbs63··on A faster way to make Bose-Einstein condensates
You can't actually suck all the energy out - the best you can do is get the atom into its ground state, which is still non-zero.

The de Broglie wavelength of the atom is (h/p), where h is Planck's constant, and p is the atom's momentum. This is the wavelength of the atom's probability wave, so at the minimum value of p, the atom has some 'fixed maximum size', if you want to call it that (but size isn't really an accurate descriptor, more like 'the region in which you might find the atom').

The Bose-Einstein condensate is defined as the state where the de Broglie wavelength for atoms in a cloud is larger than the spacing between atoms - the probability waves overlap, and it is no longer possible to distinguish one from another.

mgibbs63··on That’s a Big Microscope
As a die hard LCLS supporter, I have to say: XFEL has the more powerful electron beam, but LCLS is still in the lead in terms of X-rays right now (if pulse intensity/peak power is the measure).

XFEL is really an amazing machine, though, and once it is fully commissioned, it will take the X-ray crown as well.

mgibbs63··on That’s a Big Microscope
Synchrotron lightsources are a dime a dozen. For real power, you want a free electron laser. The Linac Coherent Light Source at SLAC (right in Silicon Valley's back yard) pumps out an X-ray beam with about 750,000 times as many photons per second, and in pulses that are about 200 times faster.

https://portal.slac.stanford.edu/sites/lcls_public/aboutlcls...

mgibbs63··on The Ripple Effects of Rising Student Debt
The HOPE Scholarship (the Georgia in-state scholarship program) still exists, but since the early 2000's, it has become considerably harder to qualify for. It used to be as easy as graduating from a public high school in Georgia with a 3.0 GPA, and would cover all your tuition, up to 15 credit hours per semester. Once you were in college, I don't believe there were even any GPA requirements. Today, I think you need a 3.7 GPA to qualify. EDIT: Looks like you still just need a 3.0, but there are additional 'academic rigor' requirements on the high school courses you take.

It was a spectacular bargain (and still is, but to fewer students), and paid for my degree at Georgia Tech, which is a pretty good school. The system is funded by lottery revenue, though, which brings up some thorny issues. The majority of people who buy lottery tickets are working class, but the majority of HOPE recipients are upper-middle class - effectively a bizarre reverse-welfare program.

In most other states, similar programs don't exist, and even students who are willing to stay in-state and work while they go to school end up with some student debt.