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location Princeton, NJ
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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).


Aug
6
comment How much Energy to create a 'warp field' according to White?
"without violating known laws of physics": It basically violates all the laws of physics, as Jerry Schirmer rightly points out. The existence of such a phenomenon would change the causal nature of the universe - any experiment could be altered by things warping in from spacelike-separated regions or even the future, meaning all predictability and indeed all science as we know it just stops working.
Aug
4
comment Regarding space launch hazard and near earth debris
@Dilaton Perhaps it would be better there, but that logic is not sound. Whether or not a question belongs here is a judgement made independently of whether or not it would be even better off elsewhere.
Aug
4
comment How vacuous is intergalactic space?
Regarding the last sentence: Not only does this density help pin down the large-scale features of our universe (will it recollapse or expand forever? etc.), but it is absolutely essential in figuring out how far radio waves travel.
Aug
3
comment Space expanding, or light slowing down?
While it is true that $c$ is constant as far as anyone can measure, and while part of the evidence comes from distant objects, this statement leaves something to be desired - namely how this measurement is done. It is in fact a nontrivial astronomical measurement, since you can't just go to a distant galaxy in the past and measure the speed of light there. Even spectroscopy runs into problems if all you can see is, say, the Balmer series.
Aug
3
comment What are physical effects that could be employed to emulate this system?
This seems wayyyy too contrived to match nature. There aren't many physical systems that match tree structures I can think of (and certainly there are no self-similar hierarchies more than a few levels deep), and the added requirement of having the data stored in the node reference the tree structure itself - that's just asking for too much. Maybe biology could cook up something where tree depth corresponds to a signalling chemical concentration, but that's still a huge stretch.
Aug
3
comment how does international space station change its orientation?
@Hash Note that as written this is borderline on topic for this site (the physics of space maneuvers is on topic, but engineering implementation details are generally not). However, this is the perfect sort of question for the new Space Exploration site, so if you have future questions like this you may also want to consider asking there.
Aug
2
comment Are elliptical orbits really elliptical?
@Wutaz Unless you put in the general relativity yourself ;) I assure you the simulation is not able to compute apsidal precession. That's just an example of how one can get a similar phenomenon using different laws of physics. The only "tiny deviations" in pure Newtonian mechanics are the result of (1) other bodies in the system or (2) the bodies not being perfect, rigid spheres.
Aug
2
comment There is no electricity at home,I need to light a 15W CFL Bulb.Can I Do it with the help of a hamster?
This question appears to be off-topic because it is about biology.
Aug
1
comment What highest amount of energy can we get from a laser?
Ummm, a laser has exactly as much energy as you put in, like a light bulb. It is certainly not a source of energy. Perhaps you could clarify what you mean?
Aug
1
comment Is there a star catalog for download?
This request is pretty unspecific. How deep do you need the catalog (and are you measuring by magnitude or distance)? Will partial sky coverage suffice?
Jul
31
comment Can gravity be shielded, like electromagnetism?
The second paragraph is a bit misleading. Yes, dark energy can be said to "repel," but this is due to it having a negative pressure; it's energy density is still very much positive. In terms of some standard energy conditions, it saturates null, weak, and dominant, and it only violates strong. [Warning: The rest of that wiki article contains some rather blatant factual inaccuracies itself; I suggest not relying on the other sections.]
Jul
30
comment Saturn V specific impulse issue in velocity modelling with Tsiolkovsky's equation against actual values?
At any time there is guaranteed to be at least one grad student around who is looking for ways to avoid research. Karan K: if you aren't familiar with Latex, it's a great thing to learn. You can click edit on this question now to see how I formatted things - and at least 95% of what I did is "proper" and not a hack :)
Jul
30
comment Why does a car go down the hill backwards even though the engine keeps running?
Hi Saxman, and welcome to Physics Stackexchange! Rather than posting updated as new answers (as one would do in a forum), our Q&A style favors editing your original answer to include more information, especially since answers are not necessarily presented in chronological order. Could you edit this information into your other post?
Jul
30
comment Surface integral of a line
It would help to have more context. Barring the appearance of infinite quantities, the surface integral of a field goes to 0 as the surface is retracted to a line. Analogously, the regular integral over an interval of the real line will go to zero as the interval collapses to a point, unless you have some fishy delta-function stuff going on.
Jul
30
comment Help on applying a Hadamard gate and CNOT to two single q-bits
Might be worth pointing out for the OP's sake that the implicit product here is the tensor product, $\otimes$, which does indeed distribute over addition. It might be "basic" for multiparticle QM, but I feel most pure linear algebra 101 courses for non-mathematicians won't cover it.
Jul
29
comment Closed linear cosmology implies G M / R = c^2?
I'm curious where this linearity assumption comes from. The Friedmann equations give you $R$ as a function of $t$ - I've never seen an assumed form for $R(t)$ be inserted into them.
Jul
28
comment Are there any naturally occurring perfect circles?
Essentially a duplicate of Do spheres exist in nature?, given the substitution circle $\to$ sphere.
Jul
27
comment Question about teeter totters or see saws
A finely-crafted mechanical balance is a beautiful thing. They have just enough restoring force to overcome friction in the case of equal masses, but no more than that.
Jul
27
comment Why are most metals gray/silver?
@babou That page you linked does not discuss the case at hand (color due to the sea of electrons in a conduction band in an extended chunk of metal) but rather only color of single ionic complexes in and out of solution. I take this as a sign that this is a good question for us to address. This is especially good when one considers the subtle fact that the two most notably non-silver-colored metals have the same valence electron configuration, but yet the paradigmatic achromatic reflector, silver itself, is in the same column of the periodic table.
Jul
27
comment Are orbits reversible in general relativity?
Addressing just the last sentence - there is a whole subfield of astronomy concerned with the paths light takes near strongly gravitating bodies. This is because we observe many binary systems with at least one member being a white dwarf, neutron star, or black hole, and at least one member a glowing object. We would like to understand the amount of light we receive as a function of time. Often this analysis is done with some form of ray tracing.