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Right, because daring to ask "why" is trolling. Apparently it's entirely inconceivable that I did already click the one link provided, read through it yet agai

Right, because daring to ask "why" is trolling. Apparently it's entirely inconceivable that I did already click the one link provided, read through it yet again (as if it's the only time someone's thrown a Wikipedia link at me), and - finding that it still does not answer my question - indicated such. Asking why tachyonic antitelephones are relevant to a discussion about forms of superluminal communication that do not involve tachyons is not trolling. Like, I'm really not trying to be confrontational here (well, at least I wasn't, until you decided I was and immediately decided to be a jerk about it). These are honest questions I'm asking, and I wouldn't be asking them if the answers were really so obvious that no explanation (beyond "here's a tangentially related Wikipedia link, now bug off") is worthwhile.

SideburnsOfDoom 6y ago
> Asking why tachyonic antitelephones are relevant to a discussion about forms of superluminal communication that do not involve tachyons is not trolling. If it's not trolling it's completely missing the entirely of the point. I mean, really? There are no tachyons, it's just a way to talk about literally any forms of superluminal communication. The maths is the same. Are you familiar by "proof by contradiction"? (if not, google it and don't bother me) It's a very basic thing, that proceeds along the lines of "assume not x ... steps ... therefor 1=2" and it proves x, because "not x" cannot be true. Now "tachyon" above is merely "assume something faster than light". and it gives rise to contradiction. I can talk about it for you, but I can't understand it for you. Are you familiar with "thought experiment"? > I immediately decided to be a jerk Jerk is as jerk does. We're at the point where it's impossible to say if your misunderstanding are deliberate or not, since you admit to jerkiness.
- yellowapple 6y ago
  sigh Here, can we reset a bit? Obviously we didn't start this conversation on the best note, so I guess it shouldn't be surprising that it's gone sour, but that doesn't mean it has to stay that way, right? I'm sorry for my own jerkiness. Let's start over: Howdy! I'm YellowApple, and I have some questions about the implications of superluminal communication... > There are no tachyons, it's just a way to talk about literally any forms of superluminal communication. So I think this the core of my question. If we can agree that these signals are not themselves tachyonic, then why are we subjecting them to mathematics that do assume them to be tachyonic? That is: the math on that Wikipedia page seems to specifically describe signals that are moving faster than c within their own reference frames, whereas we're discussing spacetime topologies where that shouldn't be necessary - i.e. where from the signal's perspective it's moving slower than the speed of light. So if from the signal's point of view it ain't moving faster than c, how would it still result in a negative t? > Are you familiar by "proof by contradiction" I am, yes.
  - SideburnsOfDoom 6y ago
    Signals slower than the speed of light (or even at the speed of light, e.g. radio signals in space) are ordinary and have no paradox, so there's nothing to debate. Unless you're thinking of "loopholes", e.g. "the Rocinante travels through the stargate to the Illus system, and since it travels through the gate at 100 km/h with respect to the gate, it's clearly not superluminal". The answer is that light takes 104 years to travel from our solar system to the Illus system, so yes it very much is superluminal, there's no way around that. Same applies to "the Enterprise travels in warp bubble where it's at rest". If it's 8 light years to Wolf 359 and you get there before lunchtime, it's superluminal regardless of warp bubbles. Debating how your signals or spaceship carrying a message travel is pointless - the only question is, did it get there faster than light would or not? You can't have your cake and eat it too here. BTW: I already said off of that: > Literally any method of getting from A to B faster than light would, has a causality paradox. it does not matter if you cover the miles between FTL, or pop out of a hypothetical wormhole gate: If you end up outside of your own light cone, no matter how, there's a causality paradox.
    - yellowapple 6y ago
      > Signals slower than the speed of light (or even at the speed of light, e.g. radio signals in space) are ordinary and have no paradox, so there's nothing to debate. Okay, but that's the thing: from one perspective (the signal's) the signal is indeed subluminal, but from another (an observer's, e.g. the sender or recipient) it's not. So which math applies? > The answer is that light takes 104 years to travel from our solar system to the Illus system, so yes it very much is superluminal, there's no way around that. Except there is a way around that, no? Specifically that from the signal's point of view it was not actually superluminal, and therefore not subject to the infinite energy requirements of locally-superluminal travel? If A sends a message at tA=1, and it takes one second for the message to reach B (so, tB=2), then how does that result in tA > tB? No matter which frame of reference we're using (A's, B's, the signal's), I'm failing to see where causality would invert. That is, going back to the start of this conversation: > If you end up outside of your own light cone, no matter how, there's a causality paradox. From which frame of reference is that light cone authoritative? If I'm B, and A sends me two copies of a message - one by some wormhole or warp pigeon or whatever, and one by radio - and the W message takes 1 second while the R message takes 10, then where does that leave room for the W message to reach me before it was sent? The math behind a tachyonic antitelephone - as far as I can tell - only answers this for cases where the signal is itself traveling faster than c within its own frame of reference, but that wouldn't be the case in this situation.

SideburnsOfDoom 6y ago

> Asking why tachyonic antitelephones are relevant to a discussion about forms of superluminal communication that do not involve tachyons is not trolling. If it's not trolling it's completely missing the entirely of the point. I mean, really? There are no tachyons, it's just a way to talk about literally any forms of superluminal communication. The maths is the same. Are you familiar by "proof by contradiction"? (if not, google it and don't bother me) It's a very basic thing, that proceeds along the lines of "assume not x ... steps ... therefor 1=2" and it proves x, because "not x" cannot be true. Now "tachyon" above is merely "assume something faster than light". and it gives rise to contradiction. I can talk about it for you, but I can't understand it for you. Are you familiar with "thought experiment"? > I immediately decided to be a jerk Jerk is as jerk does. We're at the point where it's impossible to say if your misunderstanding are deliberate or not, since you admit to jerkiness.

yellowapple 6y ago
sigh Here, can we reset a bit? Obviously we didn't start this conversation on the best note, so I guess it shouldn't be surprising that it's gone sour, but that doesn't mean it has to stay that way, right? I'm sorry for my own jerkiness. Let's start over: Howdy! I'm YellowApple, and I have some questions about the implications of superluminal communication... > There are no tachyons, it's just a way to talk about literally any forms of superluminal communication. So I think this the core of my question. If we can agree that these signals are not themselves tachyonic, then why are we subjecting them to mathematics that do assume them to be tachyonic? That is: the math on that Wikipedia page seems to specifically describe signals that are moving faster than c within their own reference frames, whereas we're discussing spacetime topologies where that shouldn't be necessary - i.e. where from the signal's perspective it's moving slower than the speed of light. So if from the signal's point of view it ain't moving faster than c, how would it still result in a negative t? > Are you familiar by "proof by contradiction" I am, yes.
- SideburnsOfDoom 6y ago
  Signals slower than the speed of light (or even at the speed of light, e.g. radio signals in space) are ordinary and have no paradox, so there's nothing to debate. Unless you're thinking of "loopholes", e.g. "the Rocinante travels through the stargate to the Illus system, and since it travels through the gate at 100 km/h with respect to the gate, it's clearly not superluminal". The answer is that light takes 104 years to travel from our solar system to the Illus system, so yes it very much is superluminal, there's no way around that. Same applies to "the Enterprise travels in warp bubble where it's at rest". If it's 8 light years to Wolf 359 and you get there before lunchtime, it's superluminal regardless of warp bubbles. Debating how your signals or spaceship carrying a message travel is pointless - the only question is, did it get there faster than light would or not? You can't have your cake and eat it too here. BTW: I already said off of that: > Literally any method of getting from A to B faster than light would, has a causality paradox. it does not matter if you cover the miles between FTL, or pop out of a hypothetical wormhole gate: If you end up outside of your own light cone, no matter how, there's a causality paradox.
  - yellowapple 6y ago
    > Signals slower than the speed of light (or even at the speed of light, e.g. radio signals in space) are ordinary and have no paradox, so there's nothing to debate. Okay, but that's the thing: from one perspective (the signal's) the signal is indeed subluminal, but from another (an observer's, e.g. the sender or recipient) it's not. So which math applies? > The answer is that light takes 104 years to travel from our solar system to the Illus system, so yes it very much is superluminal, there's no way around that. Except there is a way around that, no? Specifically that from the signal's point of view it was not actually superluminal, and therefore not subject to the infinite energy requirements of locally-superluminal travel? If A sends a message at tA=1, and it takes one second for the message to reach B (so, tB=2), then how does that result in tA > tB? No matter which frame of reference we're using (A's, B's, the signal's), I'm failing to see where causality would invert. That is, going back to the start of this conversation: > If you end up outside of your own light cone, no matter how, there's a causality paradox. From which frame of reference is that light cone authoritative? If I'm B, and A sends me two copies of a message - one by some wormhole or warp pigeon or whatever, and one by radio - and the W message takes 1 second while the R message takes 10, then where does that leave room for the W message to reach me before it was sent? The math behind a tachyonic antitelephone - as far as I can tell - only answers this for cases where the signal is itself traveling faster than c within its own frame of reference, but that wouldn't be the case in this situation.