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Don't worry too much about the word "matter": the modern view afforded by GTR, quantum field theory and much more means that the word "matter" has become very vague. If you look up the "matter" Wikipedia page, this seems to agree that the word "matter" is very vague now indeed, so as a useful concept in physics, the word seems clearly to have passed its ...


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Yes gravity affects voltages and forces in circuits but has very small effect suppose you have vertical wire on globe directly which is 1 meter ,electron mass is 10 power -31 kg,and you know globe mass and radius , by simple calculations depending newton's law of gravity and work's law you get: the voltage gravity applied on wire is 10 power -26 and it ...


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Well, if it is constant, then it's equivalent. Inertial mass is the resistance that a body offers when a force tries to change its state of movement. So it is the $m$ that appears here $$p=m\dot{x}$$ and here $$F=m\ddot{x}.$$ But if it's not constant you can see it as the magnitude that appears in $$ p=m\dot{x} $$ because in the force expression, ...


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Entering at x does take you to the future. If this is not explicitly stated in Morris and Thorne 1988, Thorne does explicitly state this in his 1994 book Black Holes and Time Warps -- Einstein's Outrageous Legacy. You'll find the following sentences on page 504, "The wormhole has become a time machine. If I now (on 1 January 2010) climb into the ...


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This seems to be called the eternal-time-machine spacetime, and I believe the original paper was Morris 1988, which is available online and not paywalled. On p. 1447, they claim: ...at late times by traversing the wormhole from right mouth to left, one can travel backward in time (i.e., one can traverse a closed timelike curve)... The question says: ...


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This is exactly the source of energy exploited by the fission of high-mass nuclei (i.e. nuclear power). You start with a heavy nucleus (say $^{235}\mathrm{U}$) and add a neutron. What you get out is two lighter nuclei (often, but not always, krypton-92 and barrium-141) and several neutrons: $$ ^{235}\mathrm{U} + n \to ^{92}\mathrm{Kr} ^{141}\mathrm{Ba} + ...


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This effect was originally predicted in special relativity, time slows for an object undergoing acceleration compared to the observer, but Einstein's big leap to general relativity was realising that gravity is an acceleration - standing on the surface of the Earth or sitting in a rocket accelerating at 9.8m/s/s are (as far as the time dilation go) the same ...


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There is a simple thought experiment that you can use to show this. Consider a rocket accelerating in space, and consider a clock at the top of the rocket, and a clock at the bottom of the rocket. If we do this, we'll note that, if the rocket is going away from us, then the clock at the front of the rocket will have sent light to us at a time when the ...


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It's a fundamental principle of both special and general relativity that the line element, $ds$, given by the metric: $$ ds^2 = g_{\mu\nu} x^\mu x^\nu \tag{1} $$ is an invariant. That is, all observers in any coordinate systems will calculate the same value for $ds$. It's this fundamental symmetry that is responsible for time dilation, along with all the ...


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Yes, because what slows down clocks is acceleration, whether by gravity or by centrifuge, if you like. It doesn't matter how fast the airplane is, but how high it is, because gravity is stronger at lower elevations.



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