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location Princeton, NJ
age 25
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I am a graduate student studying astrophysics at Princeton. I received my bachelor's in physics and mathematics from Caltech (2011).

My primary interest is in general relativistic magnetohydrodynamics simulations of black hole accretion.


Dec
19
comment Does radio use virtual photons?
See the answers to Are W & Z bosons virtual or not? for examples of how physicists confuse themselves with the word "virtual."
Dec
18
comment Converting heat into energy
Specific engineering recommendations are off topic here, and is probably why close votes are being accrued. I for one think this shouldn't be closed, as long as it is understood that all we deal with here are absolute physical limits (e.g. the Carnot efficiency).
Dec
17
comment Relativistic Black Hole?
Aside from the subtleties of relativistic mass (a terrible idea by the way - it was a mistake for physicists of the past to introduce such a concept due to all the confusion it causes), it should be noted that the electron is a point particle and as such doesn't have a radius.
Dec
16
comment Why isn't temperature frame dependent?
@dmckee this one? physics.stackexchange.com/q/83488
Dec
16
comment Can sand falling in a floating hourglass cause it to sink? (Follow up to hourglass question)
@BMS Based on fibonatic's answer it doesn't - this setup just seems to be designed for the sole purpose of confusing physics students with regard to the original hourglass question.
Dec
13
comment How would neutron matter appear to the naked eye?
@Wet Actually, all gravity does is shift the equilibrium concentration. Neutrons still decay in neutron stars, but they are being reformed by combining protons and electrons. Because both reactions release high-energy neutrinos, neutron stars cool by maintaining equilibrium, paradoxically enough.
Dec
11
comment Proof of conservation of information
possible duplicate of Why is information indestructable?
Dec
8
comment Is wearing 3D glasses from the cinema as sunglasses hurtful to the eyes?
I'm... not sure I understand this answer. I don't think the OP was suggesting looking directly at the Sun - that would be foolish with or without sunglasses. And certainly walking around outside with nothing on is safe, so walking around with 3D glasses on is no worse, if a bit weird. Besides, any glasses you get that cost less that $500 are UV-opaque, since they will either be made of non-quartz-crystal glass or of organic-double-bond-rich plastic. "UV-blocking" is just a marketing ploy to get people to pay more money.
Dec
7
comment How would neutron matter appear to the naked eye?
Note that even in neutron stars the equilibrium between neutrons and protons/electrons still consists of plenty of the latter, especially when considering the absolute density.
Dec
6
comment How is distance measured to far away stars and galaxies?
Neither parallax nor redshift work for Andromeda. Even with Gaia parallax can only be measured for a small fraction of our own galaxy; redshifts don't work for the closest few hundred galaxies.
Dec
6
comment Redshift Dependence in the Spatial Orientation of SDSS Galaxies having Redshift 0.19 to 0.20
It's not really clear what you're asking. Is there a real correlation between redshift and orientation? Is there some bias introduced in the SDSS pipeline? Clearly there must be background to this question, given those specific numbers.
Dec
6
comment Why is spectrum obtained by sunlight, said to be continuous?
an astrophysicist could probably tell you how many - A few tens of thousands of years at least, maybe upwards of a hundred thousand depending on how you estimate things :)
Dec
5
comment Atomic Orbitals, Singlets, Triplets
@Anonymous I think I'm starting to understand your concern. There are triplets, and there are triplets. P orbitals are triplets in that there are 3 degenerate levels, and S orbitals are singlets in the same sense. However, independent of atoms and orbitals, two spin-1/2 particles together can be viewed either as $|1/2,m_1\rangle \otimes |1/2,m_2\rangle$ (the tensor product of two identical Hilbert spaces) or as $|0,0\rangle \oplus |1,m\rangle$ (the direct sum of a singlet Hilbert space and a triplet one). This latter idea doesn't really connect with atomic orbitals, however.
Dec
5
comment What's the point of Hamiltonian mechanics?
Should that second $2n$ be just $n$? I would hope the Lagrangian method doesn't require twice as many IC's.
Dec
1
comment Death by neutrinos - polonium go home
"neutrinos account for only a small amount of the energy shed by a supernova" - I thought the $\nu$ luminosity was $\sim 100$ times the optical luminosity.
Nov
25
comment Do low frequency sounds really carry longer distances?
Nice. Now that you've considered 3 times as many effects as would warrant a good answer, here's another to ponder :) Any real medium will have dispersive and diffusive effects. Dispersion in particular means the crests of a sound wave will travel slightly faster than the troughs, resulting in waveform steepening (i.e. shifting of power into higher frequencies), ultimately resulting in a hydrodynamical shock. I wonder over what length scale that occurs, but perhaps it's worth a separate question.
Nov
25
comment What is the name of the temperature limit beyond which an explosion will form a mushroom cloud?
I could believe the critical parameter could be described in a number of ways, and you can switch amongst them using assumed parameters for your particular situation (density of your medium, value of $g$, etc.).
Nov
22
comment Determining source of neutrinos
arXiv version was posted today too: arxiv.org/abs/1311.5238 Also, these would be the second extrasolar neutrinos, the first being from SN 1987A.
Nov
22
comment Reference request: Hollow concave Earth hypothesis
That journal is more than a bit ... fringe ... and the paper moreso from what I've seen in references to it. I would hope no university I'm affiliated with would subscribe to such stuff.
Nov
22
comment Do nanoscopes exist?
One should perhaps mention that electron microscopes and particle accelerators are not exactly priced for consumers.