musgravepeter

8 ms·

31.
by musgravepeter 8y ago
>Regardless of your learning style, you'll still need to solve the physics problems in each textbook. Solving problems is the only way to really understand how the laws of physics work. There's no way around it. Even though it
32.
by musgravepeter 8y ago
I need to read this more carefully, but a discontinuity in the derivatives of a system of equations at an interface is fairly common. If there are two regions obeying Maxwell's equations with a difference in the derivatives of the E&#x
33.
A survey of black hole thermodynamics(arxiv.org)
1 points by musgravepeter 8y ago|0 comments
34.
by musgravepeter 9y ago
I'm lucky since I am by nature an early bird. I work on my side project for an hour or so before work. Also a few hours in the morning on the weekend. IIRC this was how Scott Adams found time to draw Dilbert when he had a full-time j
35.
by musgravepeter 9y ago
"This century has been so rich in discovery and so packed with technical innovation that it is tempting to believe that there can never be another like it. That conceit betrays the poverty of our collective imagination." John Mad
36.
by musgravepeter 9y ago
Take a look at SageManifolds: https://hyperspace.uni-frankfurt.de/2017/01/20/sagemanifolds... My understanding is the numerical GR community is moving in this direction. The theory people tend to roll their o
37.
by musgravepeter 9y ago
This might be of interest for spacetime modeling: https://arxiv.org/abs/1712.07658
38.
by musgravepeter 9y ago
The close encounters will cause issues even in integrators more sophisticated than Euler. One body of research used regularizing integrators to change variables when the bodies get close, to avoid numerical instabilities. This integrator is
39.
by musgravepeter 9y ago
Yes, that does work. In the literature this is called a "heirarchical system" The very simplest version is called the Euler problem. Two fixed masses and a third moving in the "dipole field". All the solutions can be ex
40.
by musgravepeter 9y ago
With some symmetry you can find a couple of solutions, which is what Laplace and Lagrange did. e.g. http://www.phys.lsu.edu/faculty/gonzalez/Teaching/Phys7221/T... The scholarpedia article is a good meta
41.
by musgravepeter 9y ago
The pre-print from arxiv: https://arxiv.org/abs/1705.00527v4
42.
by musgravepeter 9y ago
I did a project like this to get three body physics for an iOS/Android app Three Body. ( http://nbodyphysics.com/blog/2015/12/ ). Converting Fortran from 1973 into C# for Unity. This code (only 1000 or so
43.
by musgravepeter 9y ago
http://theoreticalminimum.com/ Lectures by Susskind for people who know (or have forgotten) some calculus and always wanted to know more about physics.
44.
by musgravepeter 9y ago
"I’m the master now. Yes that sounds arrogant and I don’t think I’m going to add that word to my LinkedIn," Sometime a change in language helps to soften a word with too many associations: software guru ?
45.
On being the dumbest guy at a relativity conference(nbodyphysics.com)
2 points by musgravepeter 9y ago|0 comments
46.
by musgravepeter 9y ago
That book looks very interesting. Thanks for the tip.
47.
by musgravepeter 9y ago
Entirely on the side. I ended up in telecom SW but always tried to putter away on physics-based side projects (e.g. Geodesic Asteroids and Three Body apps on iOS, Android). In playing with geodesic equations I tried to use GRTensorII on my
48.
by musgravepeter 9y ago
I found Carroll's book excellent (the notes seems very similar). As the author of a tool for GR calculations (grtensor on github) I've been collecting intro GR books. I did my PhD in GR 20 years ago and am getting back into it. My
49.
by musgravepeter 9y ago
Guess I have some work to do to update my mobile app Three Body! (It presents galleries of solutions up to those found in 2013, and lets you explore your own initial placements) iOS: https://itunes.apple.com/us/app&#x2F
50.
by musgravepeter 9y ago
Easily the book I have re-read the most times.
51.
by musgravepeter 10y ago
If you go to http://www.astro.princeton.edu/universe/ you can find print-outs of the entire universe all the way to the microwave background (log scale). They're very cool.
52.
by musgravepeter 10y ago
To me the key point is "no clear answers" in philosophy. In math you learn to follow a series of developments, building structure that leads to statements that are true. These are the foundation for more bricks in the wall and eve
53.
by musgravepeter 10y ago
I find that a bit mis-leading. While IAAP, this is not my area. My understanding is the at the big bang there are a HUGE number of universes (the Multiverse) that are causally dis-connected, with different coupling constants for the forces
54.
by musgravepeter 10y ago
I don't think there is any intent to be misleading. I agree that reading this blog by itself is jumping into the middle of the conversation, and terms are not explained. The multi-verse has been discussed there for years, so occasional
55.
by musgravepeter 10y ago
Depending on what "being a physicist" means, I did. Went from EE undergrad to physics PhD. Then worked in s/w but still tinker on physics projects on the side. GRTensorIII ( https://gitlab.com/grtensor/grt
56.
by musgravepeter 10y ago
"It boils down to a single “new physics” ingredient in black hole physics as soon as quantum effects are being considered: from now on, when quantised particles and fields are considered, only those general coordinate transformations a
57.
The firewall transformation for black holes and some of its implications(arxiv.org)
2 points by musgravepeter 10y ago|2 comments
58.
by musgravepeter 10y ago
Fun. I love that weird intuition trap you mention - the volume of a N dimensional sphere of radius R sphere goes to zero as N -> infinity. https://en.wikipedia.org/wiki/Volume_of_an_n-ball
59.
by musgravepeter 10y ago
(long) Thanks for the interest. It is quite an odd career trajectory. I was torn about physics vs engineering when I went into undergrad - and the advice I got was one led to more certain income - so engineering it was. However, I always fe
60.
by musgravepeter 10y ago
I did math in the wrong order. I first was "exposed to it" as an engineer undergrad - didn't care at all (just wanted to code) and barely passed eng. math. After working for two years, went back and did undergrad physics cour

More ›