Ask HN: Physicists of HN, what are you working on these days? • Hacker News Board

Re: Ask HN: Physicists of HN, what are you working on these days?

#141

Post by jqgatsby » Wed, Mar 27, 2019, 3:34 PM UTC

I am not a physicist, but one thing I've noticed is that the physicists I know tend to be very good at Mathematica, and if they happen to transition to a data science role, then Mathematica is sort of this secret weapon that they have.

I've been learning it for the first time recently, and there are data science problems that are somehow tractable in Mathematica that were very hard for me to do in Python. Some of this stuff, like FindDistribution, seems only to have been added in the last few years. The random process library is really amazing as well.

Re: Ask HN: Physicists of HN, what are you working on these days?

#142

Post by [deleted] » Wed, Mar 27, 2019, 3:38 PM UTC

bluedevilzn wrote: post #74

sprash wrote: post #49

Nuclear physicist now developing options strategies and corresponding specialized financial software for a hedge fund. I'd rather go back and work at the particle accelerator but there is zero chance for a permanent position as a researcher for a regular dude like me.

I bet hedge fund pays significantly more too, no?

[deleted]

Re: Ask HN: Physicists of HN, what are you working on these days?

#143

Post by Infernal » Wed, Mar 27, 2019, 3:38 PM UTC

eightorbit wrote: post #62

Just so you don't get the impression every physicist is having a fabulous time, here's me: I have a bachelors in physics. I went for a phd in biology but had to bail to work to support family, plus I can't seem to come up with original ideas. I now have a job with physicist as part of the title, but what I really do is try to read bad handwriting from records from nuclear weapons plants. It's a dull job a monkey coul…

Just a hunch - are you in the southeast US?

Re: Ask HN: Physicists of HN, what are you working on these days?

#144

Post by djaque » Wed, Mar 27, 2019, 3:41 PM UTC

(Current PhD Student)

Although the case for building new and more powerful hadron accelerators doesn't look good, accelerator physics is flourishing with other types of machines.

Particularly interesting to me is ultrafast electron diffraction (UED)[1,2]. UED is cool because you can create atomic resolution movies with speeds that can (in the near future) resolve chemical reactions as they occur. (eg. imagine being able to see a protein change conformations in a biological reaction)

This application is limited by the number of electrons we can stick in a given volume and get traveling in the same direction. The only way to improve this is by increasing the electric field in your electron gun or by choosing good materials for your photocathode. [3]

My research is on the second route and I'm currently building a measurement system that will allow us to test several theories related to how we choose these materials. Improvement in this domain is important and could open up a huge amount of research, but unfortunately doesn't get the kind of publicity that the big projects do.

[1] https://lcls.slac.stanford.edu/instruments/mev-ued

[2] Dwyer, J. R., Hebeisen, C. T., Ernstorfer, R., Harb, M., Deyirmenjian, V. B., Jordan, R. E., & Dwayne Miller, R. J. (2006). Femtosecond electron diffraction:‘making the molecular movie’. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 364(1840), 741-778.

[3] Rao, T., & Dowell, D. H. (2014). An engineering guide to photoinjectors. arXiv preprint arXiv:1403.7539.

Re: Ask HN: Physicists of HN, what are you working on these days?

#145

Post by eightorbit » Wed, Mar 27, 2019, 3:43 PM UTC

Infernal wrote: post #143

eightorbit wrote: post #62

Just so you don't get the impression every physicist is having a fabulous time, here's me: I have a bachelors in physics. I went for a phd in biology but had to bail to work to support family, plus I can't seem to come up with original ideas. I now have a job with physicist as part of the title, but what I really do is try to read bad handwriting from records from nuclear weapons plants. It's a dull job a monkey coul…

Just a hunch - are you in the southeast US?

Northeast, although I do have to travel to the SE now and then.

Re: Ask HN: Physicists of HN, what are you working on these days?

#146

Post by tMcGrath » Wed, Mar 27, 2019, 3:43 PM UTC

SiempreViernes wrote: post #128

musgravepeter wrote: post #64

Earlier quoted context omitted.

Some of the Unity asset work might fit that description e.g. provide a library of chaotic attractors packaged for use in a game. My grad work had no connection to data/stats and I have not bumped into any low hanging fruit where Riemannian geometry might be the answer!

I don't know that differential geometry ever made anything simple, so I don't know if there is any obvious fruit to be had. But there might be some, weird, unexpected fruit in the back; for instance, there exists a formulation of thermodynamics in terms of differential geometry: https://ui.adsabs.harvard.edu/#abs/arXiv:physics%2F0604164

As far as I know, a good differential-geometric understanding of nonequilibrium thermodynamics still hasn't been achieved.

The central issue is understanding how changes in control parameters (for instance concentrations of catalysts in a chemical system, or local fields in a spin system) affect the evolution of the probability distribution over states. Some work has been done in close to steady state (for instance [1,2,3]) but it's far from resolved.

This has some nice applications - designing efficient protocols for microscale devices, for instance.

[1] https://arxiv.org/abs/1603.07758 [2] https://arxiv.org/abs/1507.06269v1 [3] https://arxiv.org/abs/1201.4166

Re: Ask HN: Physicists of HN, what are you working on these days?

#147

Post by wuliwong » Wed, Mar 27, 2019, 3:44 PM UTC

I received my Ph.D. in physics from Georgia Tech in 2010 doing computational studies of synchronization of coupled neurons. After a year in industry, I went off to build my own startup. It was in the social, music sharing space. I was not able to raise money, joined a startup and have been doing software engineering for the web ever since. Recently, I've been learning ML in my spare time, it seems to be a nice intersection of some of the math I learned in physics and my more recent software engineering work.

>are there any other reasons for this as well?

I love physics, but I also love a lot of other things. I was a musician well before I was a physicist. My exit from "doing physics" was driven by a desire to start my own company. I found I really enjoyed developing software for the web, it was a nice blend of technical and aesthetic.

I think the draw of physicists towards data science is because of the familiar mathematics. My experience in recruiting data scientists is that candidates that have formal degrees in data science generally have little experience outside of school. My assumption is that these degree programs are relatively new.

>Of late, except for few headline-friendly fields (colliders, quantum computing, gravitational waves and astrophysics in general), I don't get to see/relate with a lot of activities in Physics

Do you think this used to be different?

Re: Ask HN: Physicists of HN, what are you working on these days?

#148

Post by BucketSort » Wed, Mar 27, 2019, 3:45 PM UTC

eightorbit wrote: post #85

BucketSort wrote: post #67

Earlier quoted context omitted.

Sorry for the aside, but... Haskell gang represent!

Yo! As a further aside, I do get to do some fun graphics in R and I'm pretty impressed how R has become the statistical standard and graphics too, mainly I think from one super dynamic statistician. Now that R is entrenched I can work on moving everyone into Haskell!

> I can work on moving everyone into Haskell!

So pure and innocent. I've found that programmers are not too fond of having even a simple IO operation lead to discussions of category theory. Good luck in your noble lambda crusade :-). The future is functional! Hack the type systems!

Re: Ask HN: Physicists of HN, what are you working on these days?

#149

Post by PaulHoule » Wed, Mar 27, 2019, 3:45 PM UTC

mjburgess wrote: post #13

PaulHoule wrote: post #10

When I got my PhD (1999) the American Physical Society said that you had a 2% chance of getting a permanent job in the field with a PhD. At that point you are not being judged on your merits but on your connections, ability to navigate politics, etc. (The job is way too valuable compared to the value you can give to it.) I saw a postdoc who is now rather well known struggling with anxiety over his career even though…

> I'd come to the conclusion that many papers involving "power law" distributions were bogus > after he had tenure, that he published something about it in a statistics journal If I'm reading you right, you're saying he struggled for awhile doing bogus things only to question those things outside the relevant field? (Also, can you say more about power law papers..?)

I wrote one (experimental) bogus paper. He wrote quite a few papers, I'm not sure if any of them used the experimental non-technique that was common at the time.

So there is a theory based on the renormalization group that can explain many (but not all) "fractal" phenomena that are observed.

I was part of the false paradigm of "bin up a probability distribution", "plot it up on log-log paper", and "draw a straight line."

Sometimes when you do that you will get an answer that has something to do with reality but it is not a valid answer to the problems of: "is a power law distribution a good model of this phenomenon", "what is a good estimate of the exponent", "are these two power law charts drawn from the same distribution" not to mention how to handle the problems that turn up at the highly frequent and highly rare ends of the distribution.

The root cause is this attitude

http://thinkexist.com/quotation/if_your_experiment_needs_sta...

and an academic system where power is too concentrated, where people who write review articles do the most good but get the least career advancement, etc.

Re: Ask HN: Physicists of HN, what are you working on these days?

#150

Post by tMcGrath » Wed, Mar 27, 2019, 3:48 PM UTC

vijayshankarv wrote: post #52

megnaro wrote: post #16

Earlier quoted context omitted.

I bought Modern Classical Physics last summer as a birthday gift to myself and I am also slowly going through it.

Oh wow! This looks like the physics book that I always wanted to read. Phd 2016 in condensed matter physics - now working in a mid-size (~600 people) software company as a data scientist.

Modern Classical Physics is a great book - I've recently started working through it (just about to move on to chapter 2). I'd be interested in chatting about it with others/cross-checking solutions. Anyone who's interested, drop me an email (address in my profile).

If you're thinking of getting it but want to check it out, there's a 2012 draft version that the authors have previously taught from here: http://www.pmaweb.caltech.edu/Courses/ph136/yr2012/. It's not the same as the book, of course, but from a skim it seems quite similar.