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You are not correct. If anything with information travels faster than the speed of light, then there are frames of reference in which that information arrived a

You are not correct. If anything with information travels faster than the speed of light, then there are frames of reference in which that information arrived at the destination before it left the origin. Furthermore, unless your FTL drive is limited in ways that would make it utterly useless, any FTL drive can be used to make "closed time-like loops", which would allow travelers to meet up with their own past selves.

enraged_camel 14y ago
>>You are not correct. If anything with information travels faster than the speed of light, then there are frames of reference in which that information arrived at the destination before it left the origin. No. If you send a radio signal to Mars, and then warp to Mars to find yourself there 0.1 seconds later, you are still 0.1 seconds after the moment on which you sent the signal from the point of origin. You are traveling faster than light, in the sense that you are traveling at [Earth-Mars Distance]/[0.1 sec] speed, but you are not actually traveling backwards in time to a point where you have not sent the signal yet.
- nessus42 14y ago
  Nothing you just said contradicts my statement, which was, "there are frames of reference in which that information arrived at the destination before it left the origin." I suspect that you don't know anything at all about Special Relativity, in which case, there's not much more I can tell you except to go educate yourself.
  - teamonkey 14y ago
    Special Relativity only applies to cases where there is uniform relative movement in two or more inertial frames of reference. That is not the case with this theory - the relative movement is clearly not uniform and although I've not read the paper I'm certain that the time warp provides a non-inertial frame. TL;DR - ignore Special Relativity completely, General Relativity is the only thing that applies here.
    - nessus42 14y ago
      Special Relativity applies ANY TIME that you transmit information from one point A in an inertial frame to another point B in an inertial frame. If you can use your warp drive to transmit information from A to B, then Special Relativity applies. If you cannot use your warp drive to transmit information from A to B (e.g., from Earth to Mars), then what good is it? (I've mentioned several times in this thread that you might be able to come up with some sort of FTL drive that doesn't violate causality if you put enough constraints on it to make it useless.)
      - teamonkey 14y ago
        > Special Relativity applies ANY TIME that you transmit information from one point A in an inertial frame to another point B in an inertial frame. Not true. It also implies uniformity of space-time in all inertial frames and the space between them. Since the theoretical purpose of the warp drive is to create a non-uniformity by definition SR does not apply.
        enraged_camel 14y ago
        Yeah, pretty much. I'm actually amazed that so many people (nessus included - as he seems to be the most vocal poster on this thread) do not know this.
        nessus42 14y ago
        All Special Relativity requires is that space be more or less flat between point A and point B. It doesn't matter if the information travels from A to B through a wormhole and then into another universe and then out the butt of Dumbo, if it ends up at B before light would, then causality has been violated. If, on the other hand, your FTL drive bends up space all around us to be like a giant hyperspace pretzel, (1) we're going to have a lot more problems than just a little violation of causality, and (2) causality still ends up being violated via General Relativity.
        teamonkey 14y ago
  - bluedanieru 14y ago
    This is as good a place to start as any: http://en.wikipedia.org/wiki/Relativity_of_simultaneity http://en.wikipedia.org/wiki/Relativity_of_simultaneity
nessus42 14y ago
I want to make a point of clarification about something I wrote above. I wrote: > any FTL drive can be used to make "closed time-like loops", which would allow travelers to meet up with their own past selves. That should have read "closed causal curves", or perhaps "closed space-like curves". I made the same typo on another occasion or two in this thread. "Closed time-like curves" do also exist, at least theoretically, and they also let you visit your our own past history, but they do not involve FTL travel. Instead, they are artifacts of General Relativity, in which causality is violated without traveling faster than the speed of light. They typically involve traveling around certain kinds of very massive objects. Another kind involves traveling in a very very large circle at close to the speed of light.
darkestkhan 14y ago
Wake up. Quantum entanglement is at least 10000 x c, and somehow it doesn't brake causality. And information first leaves the origin and gets to you before you know that it left its origin. But no causality is broken. Everything is still happening in proper order.

enraged_camel 14y ago

>>You are not correct. If anything with information travels faster than the speed of light, then there are frames of reference in which that information arrived at the destination before it left the origin. No. If you send a radio signal to Mars, and then warp to Mars to find yourself there 0.1 seconds later, you are still 0.1 seconds after the moment on which you sent the signal from the point of origin. You are traveling faster than light, in the sense that you are traveling at [Earth-Mars Distance]/[0.1 sec] speed, but you are not actually traveling backwards in time to a point where you have not sent the signal yet.

nessus42 14y ago
Nothing you just said contradicts my statement, which was, "there are frames of reference in which that information arrived at the destination before it left the origin." I suspect that you don't know anything at all about Special Relativity, in which case, there's not much more I can tell you except to go educate yourself.
- teamonkey 14y ago
  Special Relativity only applies to cases where there is uniform relative movement in two or more inertial frames of reference. That is not the case with this theory - the relative movement is clearly not uniform and although I've not read the paper I'm certain that the time warp provides a non-inertial frame. TL;DR - ignore Special Relativity completely, General Relativity is the only thing that applies here.
  - nessus42 14y ago
    Special Relativity applies ANY TIME that you transmit information from one point A in an inertial frame to another point B in an inertial frame. If you can use your warp drive to transmit information from A to B, then Special Relativity applies. If you cannot use your warp drive to transmit information from A to B (e.g., from Earth to Mars), then what good is it? (I've mentioned several times in this thread that you might be able to come up with some sort of FTL drive that doesn't violate causality if you put enough constraints on it to make it useless.)
    - teamonkey 14y ago
      > Special Relativity applies ANY TIME that you transmit information from one point A in an inertial frame to another point B in an inertial frame. Not true. It also implies uniformity of space-time in all inertial frames and the space between them. Since the theoretical purpose of the warp drive is to create a non-uniformity by definition SR does not apply.
      - enraged_camel 14y ago
        Yeah, pretty much. I'm actually amazed that so many people (nessus included - as he seems to be the most vocal poster on this thread) do not know this.
      - nessus42 14y ago
        All Special Relativity requires is that space be more or less flat between point A and point B. It doesn't matter if the information travels from A to B through a wormhole and then into another universe and then out the butt of Dumbo, if it ends up at B before light would, then causality has been violated. If, on the other hand, your FTL drive bends up space all around us to be like a giant hyperspace pretzel, (1) we're going to have a lot more problems than just a little violation of causality, and (2) causality still ends up being violated via General Relativity.
        teamonkey 14y ago
- bluedanieru 14y ago
  This is as good a place to start as any: http://en.wikipedia.org/wiki/Relativity_of_simultaneity http://en.wikipedia.org/wiki/Relativity_of_simultaneity

nessus42 14y ago

I want to make a point of clarification about something I wrote above. I wrote: > any FTL drive can be used to make "closed time-like loops", which would allow travelers to meet up with their own past selves. That should have read "closed causal curves", or perhaps "closed space-like curves". I made the same typo on another occasion or two in this thread. "Closed time-like curves" do also exist, at least theoretically, and they also let you visit your our own past history, but they do not involve FTL travel. Instead, they are artifacts of General Relativity, in which causality is violated without traveling faster than the speed of light. They typically involve traveling around certain kinds of very massive objects. Another kind involves traveling in a very very large circle at close to the speed of light.

darkestkhan 14y ago

Wake up. Quantum entanglement is at least 10000 x c, and somehow it doesn't brake causality. And information first leaves the origin and gets to you before you know that it left its origin. But no causality is broken. Everything is still happening in proper order.