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4h
comment Where does gravitational waves' energy go?
What makes you think it has to get transferred back to anything? most of the light energy radiated by the sun never gets transferred back either. So what?
4h
comment Are ergs commonly used in astrophysics? If so, is there a specific reason for it?
I suspect that Schrawzchild's book may have something to do with it. It dates from a period when cgs units were very common throughout science and remained a go-to text for decades into the (nominal) SI era.
4h
comment Now that gravitational waves have been discovered, what does their particle version look like?
The same thing it looked like last week. Seriously. We had this theory; it could be written in several ways. It made some prediction. Another one of those predictions was borne out experimentally (many others have already been done). But that doesn't suddenly change the theory or the previously completed work.
20h
comment How does LIGO account for curvature of Earth?
Figure it this way: the suspended mirrors at the ends of the arms are (IIRC) about 40 cm in diameter. If they hadn't considered the matter the machine wouldn't work.
20h
comment Does the Lorentz transformation necessary follow from the two postulates of relativity?
You should probably be aware that there are many other statements of "the" two postulates of relativity. In fact, this is a new one to me though they seem at first blush like they might be equivalent to the more common ways of writing them.
1d
comment Wave optics physics
You've left one condition out in writing about the Brewster's angle mediated scenario: the direction of the polarization.
1d
comment Could it be possible for man to create a star?
The old Usenet joke had you collecting the only infinite mass supply in the universe: AOL disks.
2d
comment Could it be possible for man to create a star?
"(few times grater than Jupiter" For values of "a few" on order of 70. Seriously, the Tzar bomb wasn't even a Christmas popper compared to Jupiter's sustained Virial heating and Jupiter nearly two orders of magnitude too small for even a trickle of fusion (which is what red dwarfs get; don't think "ignition" think "things are cramped enough that quantum mechanics allows the star to occasionally get lucky").
2d
comment Determine the height of a tall building with the aid of a barometer
Er ... you don't want to get down faster than you go up. Ideally you'd like to have the assent and descent take the same time because you are trying to measure the rate of change of the baseline over the course of the experiment in such a way as to optimize you estimate of the pressure at the ground at the time you take the pressure at the top. So take the elevator both ways.
2d
comment Does the electron's electric field strength differ when bounded to a nucleus from the strength in a free state?
@TheQ I think it is importnat to read Holger's question (and his previous one and his next one) carefully. He's imaging that there is some fundamental change in the electron and if you allow him to think that you've confirmed that he's going to keep making mistakes.
2d
comment Does the electron's electric field strength differ when bounded to a nucleus from the strength in a free state?
I'll expand on the comment I made on your next question: you've misunderstood what is happening with the screening effect. It is no more or less than the usual superposition of electric fields. There is no change in the charge of anything nor any change in field the contribution due to any selected particle. If you go forward thinking that there is then you will only make one mistake after another.
2d
comment Is the magnetic dipole moment in charged particles the more survivable property than the electric charge?
You've misunderstood what is going on in the screening effect. The charge of the state doesn't change.
2d
comment Fractionally charged Quarks
@LewisMiller Do you know the original source for the graph I exhibit in the question I linked? I'm trying to run down a proper citation and as my copy of Perkin's has walked out of my office I'm a bit lost.
2d
comment Fractionally charged Quarks
@garyp Note that the group theoretical model anna presents here predicted the existence of the (then unknown) $\Omega^-$ (including its charge, spin, parity and approximate mass) which was then sought and found. Historically that a was a watershed moment for the quark model being taken seriously.
2d
comment Determine the height of a tall building with the aid of a barometer
@CarlWitthoft You can, of course, read the ground pressure twice—once immediately before climbing and immediately upon descending—to get a measurement of the speed of the local change and to allow you to subtract it off to first order. These are the kind of things a experimenter learns to take for granted.
2d
comment Fractionally charged Quarks
It you won't accept the group theoretical argument (as you tell anna v below) then the question is a duplicate of How quark electric charge directly have been measured?.
2d
comment Determine the height of a tall building with the aid of a barometer
Come to think of it, I have an old-fashioned mercury-column barometer in my office right now. I think I can reliably judge to better than one torr on it. I wonder how tall a building I can find within reasonable distance? I could make a video or something.
2d
comment Determine the height of a tall building with the aid of a barometer
Consider what it is that a barometer measures and ask yourself how that quantity is related to height. Note that it is going to have to be both a very nice barometer and a fairly tall building for the conventional answer to yield any kind of precision.
2d
comment Friction and surface area. How friction does not depend on surface area?
Important point: the non-dependence on surface are is an approximate condition that applies when neither body is permanently or significantly deformed. Oh, and there is a lot of deeply interesting stuff (that I'm only vaguely up on) going on there, but it requires rather a lot of preparation to appreciate in detail (as in you'd like to have had at least upper division mechanics, E&M and QM to be properly prepared).
2d
comment Why is particle superposition still part of quantum mechanics?
To emphasize @PeterShor's comment, we run experiments that only work if superposition does occur on a regular basis and all kinds of different energy and length scales. Your question is simply predicated on a false premise.