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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).


Jul
10
comment Intermolecular Hydrogen Bonding
Yes cross-posting is frowned upon. If you ever want to migrate a question, use a custom moderator flag.
Jul
10
comment Is a non-Newtonian gas possible?
I don't think this is even a gas as the OP means it - it is a "gas" of excitations, similar to a "gas" of phonons, but it is in liquid(-ish) helium.
Jul
9
comment Question about an integration by parts in Feynman's Quantum Mechanics
I will strongly protest @Jim 's advice - just because one learns to solve QM problems (which are very easy, really) doesn't mean one truly understands QM, and the added perspectives with Lagrangians and especially Hamiltonians can only help with this understanding. Being able to solve textbook problems is a means to an end, never an end in itself in physics.
Jul
9
comment Why is powdered sugar less dense than granulated sugar?
What is "medium" sugar? Whatever it is, you've just shown it to be less dense than powdered sugar, but "normal" granulated sugar is more dense than powdered.
Jul
9
comment How effective is speeding?
@MD-Tech I see what's going on. Traveling 20 miles per hour is always better than traveling 10 miles per hour to get somewhere. Period. alemi, your second two plots show cost per hour, which is... not really useful in the real world. People (outside of LA) travel to get somewhere, not for the sake of being in their cars for a prescribed amount of time. Really, though, this is all tangential to what the OP asked - the question as phrased has nothing to do with fuel economy.
Jul
9
comment How effective is speeding?
You have one chart that shows that going faster improves efficiency at slow speeds, and another that claims going faster always costs more...
Jul
9
comment How effective is speeding?
I'm with @PranavHosangadi - I don't see fluid dynamics here. If you're capable of speeding, then there is no traffic flow issue. If there is obstructing traffic, then you can't choose your speed, so asking what speed to choose doesn't make any sense.
Jul
9
comment Pions as a superposition of quark states
This should really be broken up into two separate questions. Also, \lvert and \rangle are your friends ;)
Jul
8
comment Will a tall narrow cup keep a cup coffee warmer than a more evenly dimensioned cup?
I suspect there are far more egregious approximations I've made (like doing everything in my power to avoid convection) than ignoring radiative cooling.
Jul
8
comment Why does a flat universe imply an infinite universe?
@Void A Snake fan? I always thought of tori in terms of Asteroids myself :)
Jul
8
comment Do alternate theories for Dark Matter (like MOND) explain it's effect on gravitational lensing?
I'm personally convinced of dark matter mostly because of cosmology and the CMB, partially because of lensing, and essentially not at all because of rotation curves, and I don't think my position is too uncommon throughout astrophysics.
Jul
8
comment Classic home experiments for an 8-year-old child
Unfortunately it seems you've gotten a very long list of demonstrations, but very few pedagogically-minded ones that emphasize qualitative conclusion-drawing. On the bright side, at age 8 I was still struggling to write my name; your daughter's curriculum is about 6 years ahead of the one I grew up in.
Jul
7
comment Doughnut magnet
possible duplicate of What happens to the magnetic field in this case?
Jul
7
comment English translation of Heisenberg's paper ``Über den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik''
@NikolajK To be fair, Google translate itself said "intuitive" rather than "actual" but I only searched Scholar on the phrase "quantum theoretical kinematics and mechanics," since my ability to verify German is limited to cognates.
Jul
7
comment Basic question on the Aharonov-Bohm effect
Can I suggest $U = \mathbb{R} \times (\mathbb{R}^2 \setminus \{0\})$, to make the operator precedence clearer? Otherwise it almost looks like you are contradicting yourself.
Jul
7
comment What is the percentage of stars that are massive enough to end their lives in a supernova?
@AbanobEbrahim I think I figured it out - see the last section.
Jul
7
comment What is the percentage of stars that are massive enough to end their lives in a supernova?
I'm getting that such stars are about 1000 times rarer than that figure suggests. It could be that I made some silly arithmetic error. If anyone sees where I went wrong...
Jul
5
comment Levi Civita covariance and contravariance
I think the most common trend in the literature I see is for the lower-indexed symbol defined with signs given by the parity of the index permutation in the normal way, while the upper-indexed symbol differs from the lower-indexed one by $\mathrm{sgn}(\det g)$. But the OP seems to be in Euclidean $\mathbb{R}^3$ anyway.
Jul
5
comment Measuring Atomic Radius of a Noble Gas
The underlying question: What is an atomic radius? I sort of remember something along the lines of "half the nuclear spacing in the molecule $\mathrm{X}_2$," which obviously doesn't work for all elements.
Jul
4
comment Proving that the electronic Schrödinger equation has no closed analytic solutions for >1 electron
Really important fact: "closed-form" and "analytic" as used colloquially are basically meaningless. What you mean is "subjectively simple expression in terms of functions that I like." Is the sine function closed-form? It is if you say it is, it isn't if you say it isn't. After all, sine is only computable in the limit of infinitely many arithmetic operations, but we gave it a special name. So perfectly well-defined solutions to well-posed differential equations can be non-"analytic" to some simply because no one bothered to give those solutions a special name.