timo

I've yet to meet anyone even remotely interested in my source codes. Same goes for data analysis: no one wants to spend their time analyzing the data of other people (that's what you hire PhD students for in the first place )

Sure is. The dispersion relation (the relation between energy E and momentum p) for the free electromagnetic field is [math]E = pc[/math], which is a simplification of the more general dispersion relation for free fields ([math]E^2 = m^2 c^4 + p^2 c^2[/math]) resulting from a mass-like term that is zero (m=0). From that, you directly get a group and phase velocities [math] \frac{\partial E}{\partial p} = \frac Ep = c[/math] for wave packets of the free electromagnetic field.

That was my first thought, too (even the oh-so-lightweight Lubuntu gets beaten up by Windows 7 in terms of battery lifetime on my netbook). However, my guess would be that the main advantage of Windows comes from being able to use power saving features of components, since hardware manufacturers develop for Windows (except for Apple, of course). One example is the Nvidia ION-2 that I was initially interested in - until I read that the new power saving feature only works in Windows. My feeling would be that the processor, that has been specifically mentioned in the OP, is the smallest support problem for a Linux system.

I just wet my pants in excitement.

I don't know what you actually want to know. In my opinion, with respect to your original post you should take out that it is the "real time", defined as a measure of progress of physical processes, that changes (with respect to some reference "real time"). The behavior of clocks is just a lemma [a consequence] to this more fundamental and more interesting statement. Kind of "yes" to the first part. For the second part, note that "frame of reference" is a popular buzzword in the context of relativity, but not really an appropriate concept here. Didactically, physically, and from the point of logic it is much cleaner to take two samples, bring one at place A and the other at place B (such that the transport process can be neglected), and bring them back to after some time to compare them at a common location. One of them, the one deeper into the gravitational potential, has aged less. Simple as that. Super-surprising effect. No buzzwords involved.

So you're saying that if an sufficient amount non-outspoken extra criteria are applied to B, then A and B become equivalent, and that this then makes "the proper statement is A, not B" incorrect?

The proper statement is "time slows down", not "clocks slow down". "Time slows down" actually means "all physical processes slow down". This means: Take two similar systems. Place them at locations A and B. Some time later, bring them back to the same location. If "time slows down" at place A, then the system having been there will have undergone less physical (and therefore presumably also chemical, biological, ...) processes. A functional clock (say, driven by counting the amount of decay of some radioactive substance) is merely an experimental measure of this effect. Likewise, any properly working clock that foots on physical processes for the measurement (read: every clock) will show the slowdown (this point is probably the closest one to "miss something fundamental in my reasoning"). Two related comments: - Time is, in this case, a measure for the progress of physical effects. - For something to "slow down" you need a reference that you define "normal progress". That's what place B is for.

The existence of the webpage www.scienceforums.com is known to several people on this forum for quite a long time. There has even been a thread about it in these forums some years ago (from when www.scienceforums.com was freshly registered) - EDIT: There it is: http://www.scienceforums.net/topic/17988-scienceforumscom/ Opening posts that don't contain even a single sentence are lame.

I only know "many-worlds theory" from the Internet. My understanding of it is somewhat the following: Usually, we assume that an ideal dice after rolling shows up with one of its sides on top, where each side shows up with a probability of 1/6. Now comes ... *hocus*, *pocus*, ... I see no way to put a mathematical backup into this. More importantly (and unasked for), I see no point in it. "Observable" (effects) would probably depend on how the fancy trick works. You can probably rule out some super-fancy tricks by demanding that you reproduce the boring old single-world physics, at least in the realm where it's been observed and conceived as single world by us. One caveat in my satire above is that some effects in quantum mechanics are a bit more alien to everyday experience than throwing dice. In this case, the detour over sci-fi may in fact be a gain (which we hopefully agree it is not for understanding the probability of throwing a dice). However, no one has yet bothered to explain them to me. Bottom line: I know of a "many-world interpretation", not the "many-world theory". To my understanding (which is from internet forums, and not from any serious source at all), it is roughly as observable or math-backupable as the addition "god made" to the sentence "all objects in vacuum fall at the same rate"(*). I may admittedly miss the point of the whole issue, in which case I'd really be interested in a qualified explanation. Until then, I'm going to make fun of it (*): I probably have to state that explicitly on a science forum with a "religion" subforum: I have no problem with people believing this or finding this to make more sense to them. I'd not particularly like to have this sold as the "godmade theory", the newest development in theoretical physics, though. EDIT: As a matter of fact, there is (a) a bit more to the topic than I though, and (b) an explicit section of potential experimental tests. I particularly like (this particular example is not exactly stopping me from making fun of the "many-worlds theory", though)

You know, is not a very exact explanation of what you are supposed to do. Are you supposed to insulate the water bottle, as in "my teacher will fill the bottle with boiling water and time how long the water stays hot", perhaps? Since non-moving air is an excellent insulator, Styrofoam should indeed work quite well for insulation. Oh, and please at least try to use proper grammar and spelling when asking other people for help or a favor (I'm assuming English is your native language, here). With a little effort it's not that hard to learn, and making the impression of someone that cannot even read and write is not cool in the long run.

The translation to Visual Basic and the extension to "9 command boxes control array" (whatever that is) should be straightforward.

Why would it matter if someone came up with the same combination of letters (and possibly even the same meaning of this letter combination) before? And what would it matter for? I mean, we wouldn't exactly have to stop celebrating the beginning of the new year in either case.

Since no one has bothered telling you, yet: The TeX code for a partial derivative symbol is "\partial" (who would have guessed ).

... so essentially you ran the place down after IMM stopped to clean up after you. Could have guessed so.

What's a "PA program"?

You have your personal avatar displayed on the right of your posts, for which you could pick a logo.

A particle that moves faster than the speed of light but otherwise behaves like a cannon ball can be reliably detected with a solid brick wall. In that sense, the technology to detect objects that move faster than the speed of light does exist. EDIT: On 2nd though, you probably meant the possibility to measure the particle's speed. You'd certainly need at least two brick walls, well synchronized GPS signals, and properly connected cables for that. The point that Swansont already made remains: The detection possibility depends not only on an objects speed, but also on the type of interactions it has.

So what do you think satellite clocks would show if the two effects "acted separately"? Two times?

What's the difference between "combine" and "act separately" in this context, anyways?

Now that is in fact not true, and subtly different from "if these particles do not interact with normal matter in any way". It is well possible that yet-unknown particles interact with known matter via a yet-unknown mechanism (*). Sadly, by their very nature not much is known about unknown mechanisms. (*): Or that known matter interacts with an additional unknown mechanism or that unknown particles interact via a known mechanism.

Dark matter does not fall into your "no effect on physical particles" definition (as nothing that is the concern of physics does - but I already tried to explain that in my last post). It is in fact defined as some yet-unknown substance that effects the motion of large-scale astrophysical structures (same for dark energy). Perhaps you should be a bit more precise what you mean by "physical particles".

The worst thing that can happen is that you realize what went wrong.

That should be obvious, not only in a qualitative way but as an actual relation, from the calculation I proposed above (hint: Conservation of momentum). Oh, and the mass of a photon is zero, in case that was unclear.

Pretty much by definition there are at least no physics experiments that are not constrained by using physical particles, only. Similarly, the mainstream attitude in physics is not to worry about stuff that has no effect whatsoever (regardless whether it violates relativity or not by doing so). The idea "maybe there is something we don't know" is understandable. But if you think it through you'll realize that at least on this abstract level and in the extreme form of being completely void of consequences there's little reason to bother.

Let E be the energy of a particle, m its mass, and p the magnitude of it's momentum. E>=0, m>=0, p>=0. Furthermore, let's E, m, and p be given in suitable units such that E*E = m*m + p*p. The energy of the atom after the absorption equals that of the atom before the absorption plus that of the absorbed photon (which is called "conservation of energy"). If the momentum of the atom was zero before the absorption, then after the absorption its momentum equals that of the photon (due to "conservation of momentum"). That should suffice to calculate the mass of the atom after the absorption. Have fun!