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The Magiholes are effectively wormholes, except for the fact that the mass of their ends is fixed and unchanging, and that it can be freely moved through space. Would this cause any problems for known physical laws, compared to regular wormholes?

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    $\begingroup$ Yes. Currently wormholes are also just a mathematical construct as far as I know. Wormholes with a finite size are impossible, let alone ones you could travel through. What do you mean the mass is fixed, if the mass is fixed not mater can go through (increasing the mass) and thus you would not have a wormhole? $\endgroup$
    – D.J. Klomp
    May 23, 2021 at 12:05
  • $\begingroup$ @D.J.Klomp What if the mass is fixed, but matter can still pass through? $\endgroup$ May 23, 2021 at 12:08
  • $\begingroup$ So you have massless matter, or do you mean that if I send a kg through a kg of some other material would be send back simultaneously? $\endgroup$
    – D.J. Klomp
    May 23, 2021 at 12:11
  • $\begingroup$ @D.J.Klomp The magiholes would be able to pass matter through themself like a wormhole, but are not affected by what is passing through them $\endgroup$ May 23, 2021 at 12:18
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    $\begingroup$ @D.J.Klomp - They are a theoretical possibility in Einstein's theory of general relativity, see the traversable wormholes section of wikipedia's wormhole article. So although no one has observed one, and future theories might rule them out, according to our current best theories it's not really correct to make the strong claim that "Wormholes with a finite size are impossible, let alone ones you could travel through". $\endgroup$
    – Hypnosifl
    May 24, 2021 at 8:30

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For regular wormholes, if you put mass into one end of the wormhole, the mass of that end is going to increase. Then the mass of the other end decreases when the object comes out. This means that the wormhole satisfies the physical law of the local conservation of energy, which physicists are fairly sure is satisfied in the real universe (they're less certain about whether the global conservation of energy is compatible with the general theory of relativity).

What happens to a wormhole if you keep putting mass in at one end and taking it out the other? At some point, you break the wormhole — the general theory of relativity will predict it collapses (something that wormholes have a distressing propensity to do) and you're left with two black holes.

For your proposed wormholes, if the mass of one end doesn't increase when you put an object into that end, you break the local conservation of energy, so it's difficult to see how to reconcile this special type of worm with the law of local conservation of energy.

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    $\begingroup$ In GR, the local conservation of energy is defined on the local metric - including the wormhole itself (in the same way any small enough area of a teacup looks like a regular simple sheet). Energy can pass through a wormhole fine as long as you somehow get a stable one $\endgroup$ May 23, 2021 at 20:41
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YES

  1. The law of conservation of energy
  2. The law of conservation of momentum
  3. and probably be at least extension almost all other laws

Contradictio in terminis: Magic per definition break physics, if it did not break physics it would be physics and not magic.

Example 1: Have one wormhole situated 10 meters above ground and the other at ground level, both facing the same way. Run water into the wormhole that it keeps falling continuously and place a waterwheel with a generator in it. That is free energy.

Example 2: Have two wormholes back to back facing away from each other and throw a ball through. The momentum of the ball is completely opposite of just before without anything else in the system changing momentum. Thus no conservation of momentum.

Example 3: Because not having conservation of momentum automatically the gas laws fail.

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    – L.Dutch
    May 24, 2021 at 15:16
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Your big problem is getting the flow of time to join up, because in Relativity time flows at slightly different rates for observers moving with respect to one another, or at different potential levels in a gravitational field. The deeper you are in a gravitational field, the nearer you are to concentrations of mass, the slower times passes. In fact, you can interpret gravity as being the "refraction" effect on matter of time moving at different rates. A wave representing the ticking of local time passes from past to future in spacetime. When the wave moves more slowly through time in one place than another, the wave is bent inwards towards that part of space. Matter is pushed towards regions of slower time.

Gravity as warped time

The picture above shows time moving slower in the middle, so the waves on either side of it are bent inwards. If you try to shortcut from some place near the edge of the picture to a place in the middle, the lines through the tunnel need to be bent even more steeply to make time line up smoothly.

So if you connect a place deep in a gravity well to one higher up, time flows at different rates at the two ends, and matching spacetime up through the wormhole requires a stretch and curvature that corresponds to gravity, pulling in at the top and pushing out at the bottom. For the tiny time shifts in a planetary environment, it's not that much of a problem; it balances things like air pressure (which is higher near the surface) and prevents perpetual motion waterfalls. But the shift is cumulative, and for wormholes carried on spaceships moving at relativistic speeds, you can get "twin paradox" effects where one end can be years out of synch with the other. It potentially becomes a time machine. The wormhole links up not just to a different place but also a different time. It becomes a gateway to the past. And of course time machines introduce a whole new bunch of physical violations and puzzles.

Kip Thorne wrote a book "Black Holes and Time Warps" for the layman that goes into it in a lot more detail - well worth reading if you want to explore wormhole physics.

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  • $\begingroup$ You don't need a stardrive to get useful time differences. Knowing which way a stock price will move even a fraction of a second ahead is of use to a high frequency trader. $\endgroup$ May 24, 2021 at 22:54
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Worse: Time travel.

I suggest reading Timemaster by Robert L. Forward. Other than the handwaves needed for the story he was careful with the science. Put the two ends in environments where time moves at different rates and you get a passage through time, not just space. Present day tech is enough--take one up to the ISS for some years and you have a time machine with enough deviation to be useful to a high frequency trader close enough to wall street.

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  • $\begingroup$ I thought I recognised the name Robert L. Forward - he's a character in one of Asimov's humorous short stories (Left to Right), the punchline of which is a pun on his name. I had no idea he was a real person! $\endgroup$
    – kaya3
    May 24, 2021 at 6:03
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Violates Conservation of Energy

Consider the following setup

enter image description here

Water falls from the blue wormhole, through the waterwheel, generates energy, and from there falls into the yellow wormhole, which teleports it back out the blue wormhole, falling onto the waterwheel and generating MORE energy. . . .

This goes on forever and generates a free unlimited source of energy. This contradicts the law of conservation of energy.

Solution: Perhaps you can fix this by having wormholes require energy to create and expire after they have "created" that much energy in the manner above?

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    $\begingroup$ You could also have gravity project through wormholes I assume (so the top one would "pull things in" and bottom one "push them out" enough to keep gravity conservative on the novel metric). I think that's how GR wormholes deal with this problem, but don't quote me on that $\endgroup$ May 23, 2021 at 20:36

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