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Ways To Travel Faster Than Light Without Violating Relativity

Posted by samzenpus on from the greased-lightning dept.

StartsWithABang writes: It's one of the cardinal laws of physics and the underlying principle of Einstein's relativity itself: the fact that there's a universal speed limit to the motion of anything through space and time, the speed of light, or c. Light itself will always move at this speed (as well as certain other phenomena, like the force of gravity), while anything with mass — like all known particles of matter and antimatter — will always move slower than that. But if you want something to travel faster-than-light, you aren't, as you might think, relegated to the realm of science fiction. There are real, physical phenomena that do exactly this, and yet are perfectly consistent with relativity.

9 of 226 comments (clear)

  1. faster than light never violates Relativity by catmistake · · Score: 3, Interesting

    Nothing can go as fast as light. Slower or faster, sure, but not c.

    --
    The Admin and the Engineer
    1. Re:faster than light never violates Relativity by circletimessquare · · Score: 4, Interesting

      we have no technology remotely capable of this, but:

      1. a quantum entangled version of yourself moves away from you (at "normal" speed, less than c)

      2. say... many light years away (i know, i said we have no technology remotely capable of this, bear with me here, just a thought experiment)

      3. the "copy" of you can't violate c, but at the last moment, one version of you interacts with its surroundings, collapsing you to that single copy. such that you have achieved instantaneous transportation across light years of distances

      doesn't that happen faster than c?

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      intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    2. Re:faster than light never violates Relativity by catmistake · · Score: 5, Interesting

      You're at a very straight, very long beach. Imagine parallel waves striking the shore at a vanishingly slight angle. The point that the wave meets the shore moves along as the intersection of wave and beach occurs. As the waves get closer and closer to parallel with the beach, but not quite parallel, eventually that intersection point will be moving much faster than c.

      But the interesection point between waves and shore doesn't have mass, isn't really a "thing" that's moving.

      --
      The Admin and the Engineer
    3. Re:faster than light never violates Relativity by Anonymous Coward · · Score: 1, Interesting

      No, because it also collapses your frame of reference to a single frame. You haven't moved at all. Photons don't know they are moving at the speed of light.

    4. Re:faster than light never violates Relativity by circletimessquare · · Score: 3, Interesting

      that's an excellent analogy, thank you

      and you are correct, there's no real movement, only a collapse to a single frame of reference

      however, for the intents and purposes of outside human observers, haven't you instantly blinked across light years?

      --
      intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    5. Re:faster than light never violates Relativity by Pikoro · · Score: 4, Interesting

      I realize that this is a very simplistic explanation, but think of quantum entanglement like this:

      You have 2 cubes. Each cube can be only either blue or green. You have no idea what color each cube is as you packed them into boxes for mailing across the galaxy in a completely dark room. They are then mailed.

      Now, you open your box. Turns out that your cube is green. You instantly know that the other cube is blue, even if it's on the other side of the galaxy, however, you have no way of communicating your discovery to the other party.

      You now have instant knowledge of what color the remote cube is, but no information has been transferred.

      Simple enough?

      --
      "Freedom in the USA is not the ability to do what you want. It is the ability to stop others from doing what THEY want"
  2. Re:Article's summary by Anonymous Coward · · Score: 3, Interesting

    And even then, light in a vacuum goes slower than the actual speed of light.

    The truest speed of light can't be attained in nature due to the fact that the vacuum is not, in fact, a true vacuum. There are virtual particles popping in and out of existence constantly, which light interacts with.
    Creating 2 casimir plates to create a true vacuum would give you the true speed. What that speed may be is not known since, as far as I know, nobody has made such an experiment. But it is theorized to not be that big of a change.

    Nobody knows what effect the quantum vacuum has on EM radiation for sure.
    Hell, for all we know, it could be stealing energy off said photons, making a larger universe considerably smaller, and surely breaking some "laws" while we are at it, but since we are all about breaking the laws of physics recently, everything is up for grabs, all laws must go before 6pm!
    It is already a possible culprit for the expansion of the universe, next to dark energy.
    And given that weird ass EM Drive, that seemingly is able to bounce energy OFF of "space itself" (the vacuum), it appears that it is possible to directly interact with it, and it also gives even more momentum to Hawking Radiation being capable of stealing mass from blackholes.
    The distinction between virtual and ordinary particles just got weirder, if it holds that is. (I believe NASA is preparing a further test for next month, sometime this summer at least, to figure out what the hell that thing is doing)

    Science is going to be a very interesting topic over the rest of this century.
    Get in while you can kids. What's that, we're all old? Oh yeah. Sorta screwed that one up.

  3. Re:C is not what people think it means by firewrought · · Score: 5, Interesting

    except for the part about bringing your own fuel

    And the part about obliterating your spacecraft by colliding with interstellar dust at super-high relative velocities. The speed limit for arriving in one piece is way lower than c.

    --
    -1, Too Many Layers Of Abstraction
  4. There may be a way by PPH · · Score: 3, Interesting

    But I'm not sure TFA deals with it. Nothing can travel faster than c in a vacuum. Light travels at c (in a vacuum). However, light cannot escape from inside a black hole. This isn't due to classical speed limits, but the way space time curves near the black hole's event horizon.

    However, gravity can escape a black hole. Otherwise, how would they exist and grow? So gravity is not constrained by the same space-time curvature as light. Therefore, over long distances, the curvature of space time (even a slight effect caused by the masses of nearby galaxies) would cause the vacuum velocities of gravity to excced that of light. Or, to put another way, the path through space time for light is slightly longer than that for gravity. So gravity gets there first.

    Hint: Think about this effect as an alternative to dark matter/energy.

    --
    Have gnu, will travel.