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| Tags: cup, increase, lift, mass |
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#1
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The mass of your cup increases by the addition of the energy done in raising it
against the force of gravity. This is easily seen if one converts the results of measurement so that they are made with the same units of measurment (choose one or the other elevations as a reference). Don't get hung up with the conclusions of GR, their derivation contains a basic mathematical error and is faulty. For more information see http://www.members.aol.com/einsteinhoax/gravity.htm . For response, E-mail |
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#3
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#4
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But this creates a paradox because he claims that the total mass
will not increase. So that if the shell colapses and the sphere loses radient energy it will have less mass than it did before it was raised, for the same number of atoms. How it is a paradox? So far the total energy (together with the radiated out) is the same. If nothing radiates out then both masses (of the shell and of the sphere) are equal. My own view is that gravitational potential energy does not have mass but kenetic energy does, a raised cup has less mass. A shell with the same number of atoms will have the same mass as a sphere but when it colapses it will have that mass plus the mass of the radient energy. It seems to me as exact equivalent of what Dr. Carlip says. How is it different in your opinion? When you say "gravitational potential energy does not have mass but kenetic energy does" it is obviously true but only because there is no such thing as "gravitational potential energy" (if it existed it had mass of course since "mass" and "energy" is the same thing, E=mc^2) in Einsteinian world (a.k.a. real world). When you lift your cup you move it into place where time runs faster, and so speed of light is a little bit greater (from your point of view, not form the point of view of the cup of course), and so its internal energy (E=mc^2, from your point of view) is a little bit greater. So you have to do work that you can recover lowering the cup. No change in mass needed (or happening). Of course when you just let the cup go (not lowering it slowly, recovering the energy) then its mass goes up until the cup stops, and this will be the mass of the kinetic energy. When you calculate everything carefully you'll see that during the whole trip down of the cup its mass increases as much as its kinetic energy (from your point of view) increases but also c drops keeping the total energy constant -- a very informative exercise, with a few tricks however, so you might not get the right result the first time, but just think harder and everything will fall into place). That's the whole mechanism corresponding to Newtonian "potential energy". So as you can see there is no special "gravitational energy" involved, only the properties of spacetime, too subtle to notice, that simulate the existence of "gravitational potential energy". Similarly as other properties of spacetime simulate the accelerating expansion of the universe. It turns out that Einstein discovered more things that he is credited so far by the contemporary scientists for. -- Jim Jim Thank you for your informed and well written answer. I have a lot of thinking to do. There is something else I have a tough time with. Imagine a shell about a LY in radius with a thickness of about 4000 miles and the earth's density. Its total mass would be about three trillion times the mass of the sun and it would constitute a black hole with the same radius. The surface gravity if it were of uniform density within, about a billionth the density of earth, would give it a surface acceleration of 1g. Because the mass is concentrated in a thin shell, would the surface gravity be greater? What would the time dilation be at its center, relative to a distant observer? If the BH aspect complicates things, imagine it 2000 miles in thickness. With highest regards Stephen Kearney I would still like an answer. sk |
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#6
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