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Everything posted by pmb

  1. You're very welcome studiot. Sorry for the delay. Next time please kick me in the cyber pants so I know that I'm supposed to respond. PM me if I seem to not notice. I'd appreciate that. Thanks.
  2. Luxon's are defined as particles that move at the speed of light. Photons are a good example. But photons don't interact with each other outside of quantum entanglement. But you made no mention of the luxons being entangled and you mentioned no other reason why they should. However there was an article in Scientific American about this subject back in 1993. Faster than Light?, Raymond Y. Chiao, Paul G. Kwiat and Aephraim M. Steinberg, Scientific American, August 1993
  3. Yes, it will accelerate.
  4. Sorry. I don't know what kind of sources there are to produce those wavelengths. However it seems to me that ther are ELF (extra low freqency) waves whose wavelengths are very very long so as to communicate with submarines. The Russians use a wavelengths of 3,658.5 kilometers. http://en.wikipedia.org/wiki/Communication_with_submarines#Extremely_low_frequency It seems to me that if you found a source of EM waves with those wavelengths then you could change your frame of referene to get a different wavelength using the Doppler Effect to get a new frequency.
  5. pmb


    I disagree. I think that there are some sane people who want to kill themselves. I tried to kill myself in Jan of this year. I suffer from spinal cord disease. It's casused 4 herniated disks so far. It was going untreated. I wasn't allowed any pain medication. The pain was far too much for me to bear. I kept seeking and asking for help but met with refusal. Doctors just don't care if their patients are in pain. That's why I hate doctors. I've been fighting this pain for seven years at that point. Finally one day I just couldn't take it anymore. So I took out a razor and cut my throat open. Death was mercy for me. The only thing I could think of after being refused help for so long. I got scared and called my doctor and he called 911 so I did live, of course. It was only then was I taken seriously and they put me on suboxone (a narcotic) But come the day that I'm back with that pain again I'd surely find a tall building and jump off.
  6. Oh man! The movie "The Birds" always freaked me out. To this day I can't watch that movie! Yeeesh!!!
  7. Yeah. I do that a lot. I often edit my responses several time before I'm satisfied with it. h is the multiplier and v is the frequency variable of the photon whose energy is being determined, i.e. for a photon of frequency v it has an energy E = hv. Yep. If you recall, I answered with my web page. This question comes up a lot in physics forums. Instead of writing the same ole thing over and over I took some time to do it right and then post it when the question comes up. The page is at http://home.comcast.net/~peter.m.brown/mech/what_is_energy.htm I see it as simply a constant of proportionality between an oscialltor of frequency v having energy E = hv.
  8. Actually it was Douglas Adams who established that in the book you referred to.
  9. Hi 'elemental' - Welcome to the forum! E = hv does not indicate a fundamental multiple. I'm at a loss to see how you arrived at that conclusion. Can you explain it for me? Thanks. Note: E = hv holds for all photons, not just optical ones.
  10. We all understand that we're not supposed to get personal. However in practice anybody can give you a negative rep for any reason they want to. I believe I get a lot of that myself, i.e. ne reps by people who don't like me. I don't mind so much because I recognize these facts. You simply can't control why people vote as they do. Some people might love what you posted but not vote it up at all. Then the post might be to correct an error someone made and that correcting post might be voted down because the person who wrote it can't take constructive criticism. People have bad days too and that came show up in the writing. I've been quite sick lately and don't think I've been as polite as I'd like to be because of that. I sure hope not though. Lately I find myself up voting posts for their politeness. I always appreciate politeness. The entire purpose of all my posts is to help people understand the physics of a subject that they ask about. I have no other motive. It'd be nice to have a + vote when people thank you but that doesn't happen. But their thanks is all the reward we should need.
  11. Sorry for the delay. I didn't know you were addressing this question to me. I meant that you can give the particles in the body an increase in kinetic energy, without chaging the velocity of the object. I meant to say that so people wouldn't confuse this mass increase with an increase in relativistic mass of the object as a whole. I see that it didn't work though.
  12. I'm sorry but I don't understand your question. swansont and myself have already show you the equation that you're asking about. It's F = GMm/r^2. Since we already posted it I don't know what you're now looking for. Can you clarify this for me?
  13. pmb

    What is 'mass'?

    The definition of "gravitational field", as well as their true physical meaning, is found in Gravitation by Misner, Thorne and Wheeler (MTW) on page 467 They aren't. The first section of http://home.comcast.net/~peter.m.brown/gr/grav_force.htm defines the [math]v^{\alpha}[/math] as the derivative with respect to coordinate timne, t. Thus it is valid for luxons. The end result is derivatives with respect to coordinate time. The expression holds for both luxons and tardons. The m in it is simply [math]m = P^0/c[/math] which is valid for luxons as well as tardyons. The summation is over 0, 1, 2, 3. i and j usually denote summation over 1, 2, 3. There is a zero 4-force on a particle in free-fall. However the gravitational force is not a 4-force, it's an inertial force and as such is represented by the Christoffel symbols as is the gravitational field as seen in MTW above The definition of the gravitational force is in Basic Relativity[/b by Richard A. Mould, [i]Springer Verlag[/i], 1994 page 262 Eq. (8.65) [math]G_{\mu} = m\Gamma^{\sigma}_{\mu\tau}v_{\sigma}v^{\tau}[/math] I feel a little bit better today. I double checked my expression for the gravitational force with that of Mould's and they are identical. Mould's text was my motivation for my derivation.
  14. I find the following passage to be very comforting. From Psalm 23 King James Version (KJV)
  15. No. They're quite different. If you heat an object you are infusing it with thermal energy which means that the average kinetic energy of the atoms which make up the body increases. This happens without an increase in velocity. This causes an increase in the proper mass of the object. There is zero increase in the kinetic energy of the object and therefore the relativistic mass has nothing to do with it. Thermal energy is just one example of an energy increase and mass increase accordoing to E0 = m0c2, Here it is the m0 that increases by the addition of E0 in the form of thermal energy. But relativistic mass increase due to an increase in kinetic energy is another form of mass increase and I do subscribe to relativistic mass being a valid definition of mass. I disagree with Taylor and Wheeler on this point. They believe that relativistic energy and relativistic mass are the same thing. I disagree. I gave an example in my paper on mass where they havve different values. I don't understand your objection to relativistic mass though, given what you've said about mass in the past. E.g. in response to my giving the value of passive gravitational mass (which is identical to relativistic mass) you wrote http://www.scienceforums.net/topic/66737-what-is-mass/page__view__findpost__p__686760
  16. A counter example is the contribution to the mass of a body due to thermal energy. That mass increase is due to kinetic energy, not electromagnetic energy.
  17. I use the green positive button a good deal of the time and rarely use the red negative button. Also, I don't complain about negative rep points. As I mentioned above, I don't pay too much attention to them. I know they don't reflect who I am. I'm secure enough not to take things here personally. I also know that the neg-rep gets misused. I think that its hit when I say something someone doesn't agree with. Like when I post the definitions of such things as inertial mass or gravitational force and metion that a gravitational field need not have spacetime curvature to deflect a beam of light. These are all very true things but some people hate to see me talk about them.
  18. It's my belief that God doesn't know the future. If he did then he wouldn't have regreted having created man just to wipe them out in a flood.
  19. Science doesn't work by proving theories. Observations either provide evidence to support a theory or they can prove a theory wrong. But no amount of evidence can prove a theory right.
  20. I don't like the reputation system. It does seem ripe for abuse. Here is a good example http://www.scienceforums.net/topic/66798-light-has-mass/page__view__findpost__p__682857 In that post I responded to five comments. Each of my respones was created so as to (1) correct historical inaccuraces (2) telling a poster he wasn't dumb for asking the question (3) explain that light actually is affected by gravity (4) explain that light can be deflected by a gravitational field even in the absense of spacetime curvature and (5) agree that Einstein's books are nice to read I got a negative reputation on that post. I believe I know who did it and why it was done and in my opinion it was not for a respectable reason. Then again I don't pay attention to rep points. I simply forget to look at them. However lately I've been using them when I see people being rude or making too many errors withing a thread.
  21. I find that book to be extremely difficult for me to read cover to cover. I've tried though. I think I've completed about 70%. I'm not exactly sure though. I myself get irritated by people using the Bible to push their agenda and yet they've never read it for themselves. They go on impressions they've formed. I plan on starting to read it again in the not to distant future. Nice! Well said Phi!! I feel the exact same way.
  22. Anything which is affected by gravity is said to have passive gravitational mass. Therefore a photon has passive gravitational mass. It's equal to its inertial mass by [math]m = p/v = p/c = P^0/c[/math] where P is the photon's 4-momentum. The source of gravity is given the name active gravitational mass, by definition, and is described by the stress-energy-momentum tensor T.
  23. pmb

    Thou shalt no kill

    A lot of what I've seen plowing through this thread is about people using the term "murder" to be the same thing as kill. They aren't. God said Thou shalt not murder, not Thou shalt not kill. There's nothing wrong in killing when its not murder. Sometimes you have to kill someone to save your life or the life of someone else. God told the Hebrews to kill when they came to the promised land and found it occupied. Evolution favors self-defense, even to the extend of killing, but it doesn't favor murder when murder works in opposition to the public good.
  24. It is. It just doesn't mean that all photons are the multiple of a photon of minimal energy. Given any photon you wish you can change the inertial coordinate system to a new one in which the photon has the exact frequency that you'd like.
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