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location Princeton, NJ
age 25
visits member for 2 years, 3 months
seen 3 hours ago

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


1d
revised What mechanism is responsible for the creation of these dunes on Comet 67P/Churyumov-Gerasimenko?
best not to use astronomy *and* astrophysics for all questions (see tag wikis); astrophotography refers to the process of taking pictures (which is not an issue here)
1d
awarded  Necromancer
2d
comment Center of mass frame for massless particles
And this is why various authors say "center-of-momentum frame" instead, where conveniently/confusingly it has the same acronym.
2d
comment Failure of the Steady State Theory
@user36790 Before we settled on the Big Bang, "homogeneous" and "isotropic" would probably be interpreted as you're thinking - homogeneous and isotropic in spacetime. Once we decided the universe was not in steady state, we started implicitly restricting these terms to mean spatially homogeneous and spatially isotropic. People simply got tired of saying "spatially" everywhere, so they omitted it.
2d
comment Direction of pressure in fluids
@jake Yes. My answer to a spinoff of this question touches on this a little.
2d
answered Mathematical Reasoning for Fluid Pressure as a Scalar
Oct
22
comment How non-invasive blood glucose concentration measurement work?
This might be more readily addressed on Biology. Also, I think the device clips onto the earlobe, rather than clips the earlobe.
Oct
22
comment Recommended books for undergraduate electrodynamics
I thought the biggest flaw (other than not being Purcell, of course), was the use of that script $r$. Look at all the pain it causes for those of us who typeset undergrad homework.
Oct
22
reviewed Close Graphene has a honeycomb lattice - true or false?
Oct
22
awarded  Nice Answer
Oct
22
comment Recommended books for undergraduate electrodynamics
The "level" may feel like it's between Griffiths and Jackson, but after reading Purcell cover to cover, I picked up Jackson and realized there was nothing in the latter I didn't already know (and Jackson is wrong on several points).
Oct
21
comment Does entropy increases due to gravity?
Could you explain why you think being in a stronger gravitational field raises entropy? There may certainly be an effect on energy but in what way are you envisioning the same arrangement of particles being more disordered simply by being in a stronger field?
Oct
20
reviewed Reviewed entropy of a long molecule chain with respect to its length
Oct
20
reviewed Close Which moves faster in a time $t$: $A$ or $B$?
Oct
19
answered Really quick question about the order of operations in the Lorentz force
Oct
19
comment How Earth protected from the gamma rays generated by Sun?
@sugunan Space suits are not capable of stopping gamma rays. Nothing can stop gamma rays except by being very thick.
Oct
18
reviewed Close Self-replication of gravitons in string theory
Oct
18
reviewed Reject suggested edit on What causes a Phase-Transition?
Oct
18
comment How Earth protected from the gamma rays generated by Sun?
Minor correction to your logic: Many high-energy photons (in the regime where their interaction with matter is dominated by Compton scattering off electrons) basically only care about the column density along their path. And the full atmosphere has the same column density as 1 meter of lead (or 10 meters of water). That is, we only like dense materials because they make shielding more compact.
Oct
18
comment How Earth protected from the gamma rays generated by Sun?
@HDE226868 actually that page has a good image, since the Sun does produce some gamma rays. Its corona is millions of kelvin, so there is a (small) source other than the core.