Page 90

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Nemo
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Re: Page 90

Post by Nemo »

They've tested time dilation multiple times. It works.
http://en.wikipedia.org/wiki/Time_dilat ... tion_tests

You're hanging up on negative time, there is no negative time. Ignore time for a minute, think of physical space. When you go "up" you have a positive velocity, "down" is also movement with a positive velocity, "left & right" both positive movement, "ah ha! forwards and back!" newp still positive movement both ways. There is no negative movement, just velocities in different directions, and always forwards. Similar thing with time. The human mind thinks of time as a set of train rails with "future" and "past" owing to the way our memory works, but that's not reality. One moves through time just as one moves through space, one moves through space just as one moves through time.


Lets change the 'tachyon' pistol duel, because, honestly, pistol duels? Who does that anymore? Two starships start at point A and travel in perfectly opposite directions. Starship 1 and 2 both accelerate to .999...c and hold course and speed for 1 minute. Each fires their FTL 'tachyon' pulse cannons directly aft, targeting the other ship. Each ship scores a hit on the other ship before they fire their weapons. :shock: Say whu? With time dilation aboard ship 1, ship 2 doesn't have the time to get up to speed. With the dilation aboard ship 2, ship 1 never got up to speed. Since both ships are hit and destroyed before they fired, neither ship fires. Since neither ship fires both ships fire.... :| Say Whu? Causality has been seriously mangled.

As far as I know, for FTL to work there has to be some external force connecting separate reference frames so that causality is maintained. We don't see that. We're stuck slowboating.

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icekatze
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Re: Page 90

Post by icekatze »

hi hi

In Outsider, the problems associated with FTL travel are somewhat mitigated by circumstance. Ships are limited in how far back in time they can travel due to the velocities and distances involved. Nobody is jumping across the universe, and nobody is getting up to highly relativistic speeds during the jump process, so time dilation isn't as bad as it could be.

Still, you could set up two ships in two nearby systems, have one jump over to the next system with a message, transmit the message to the second ship just before it jumps back to the first system. That would get you some time travel, but the transit time in physical space required for a successful jump makes doing this process indefinitely a difficult proposition. So you're still going to be limited by the first point.

There may also be some temporary warping of hyperspace that occurs when a ship makes a hyperspace jump that could dilate return jumps further into the future than they might otherwise be. Not a universal frame of reference, but more like a temporary local pseudo-frame-of-reference.

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Mjolnir
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Re: Page 90

Post by Mjolnir »

Cy83r wrote:But no, seriously, how the hell do you watch someone travel back in time? My brain is running up against a wall here trying to imagine what negative time looks like. Everybody says, oh well neg time is time travel, but why? Is it just because we have so many stories that that's the first thing we think of. Somebody please tell me where the math says negative time is traveling into the past because I can't read the math.
It isn't an issue at all if FTL phenomena don't exist.

Cy83r wrote:And relativity itself is hard for me to conceptualize, being an amoral objectivist (that is objectivism without Ayn's moral bull) and a nihilist, idealist, utilitarian, determinist, and masochistic hedonist among other collections of contradictions. I accept that perception can be relative, but I rail against the idea that this phenomenon carries over to the physical execution of events. The math may allow it, but the math has allowed falsities before, and this seems to my perception and understanding to be wrong. Not only is my intuition screaming in protest, a bad gauge of the weather itself, but examples given do not seem to follow relativity in their explanations.
Again, time dilation is measured fact, an effect that commonly has to be taken into account for modern time and navigation systems. It's not a perceptual effect, it's not an illusion. Clocks taking different paths do in fact experience different amounts of time before meeting again. The difference is predictable by the math of relativity and repeatably measurable by experiment.

Cy83r wrote:For instance, in the argument about the two duelists striking each other before they even shoot, both duelists moved under propulsion before observing their time and then firing. To my understanding this is a completely invalid example of relativity in action
It's perfectly valid, up to the point where a FTL signal is involved, such signals being considered nonsensical in relativity. It's an illustration of how FTL signaling or travel doesn't make sense. The nonsensical results aren't a flaw in the argument, they are the whole point of the argument.

Cy83r wrote: and would not result in the proposed outcome for the obvious reason that both induce upon themselves a new velocity at the start of the duel and thus are both said to be in movement and that neither can be said to be able to claim the state of being at rest relative to the other.
Each sees themselves as being at rest, with the other moving. Every observer in an inertial frame can consider themselves to be at rest. It does not matter how they might have accelerated from some arbitrary reference point.

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Cy83r
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Re: Page 90

Post by Cy83r »

Nemo wrote:They've tested time dilation multiple times. It works.
Never said it didn't.
Lets change the 'tachyon' pistol duel, because, honestly, pistol duels?
'tachyon' pistol duel
'tachyon'
'tachyon'
'tachyon'
'tachyon'
Ah, I see what I missed now.

However, if both parties are experiencing roughly the same rate of dilation then... aren't they still reacting at the same speed and thus hit each other at roughly the same rate of delay? After all, the article said, IIRC, they were hitting each other instantly after firing, but FTL does not necessarily imply instant transmission from point to point, just that the transmission is faster than the propagation of light, like some sort of very odd hypersonic boom mixed with a doppler effect.

Actually, this is very much like hypersonic objects, targets are being hit by hyperlight particles, which means that they are hit before they would ever have a chance to register to oncoming object let alone the actions leading up to whatever launched said HL object at them. Even if time is wonkified according to the HL object, this effect would only occur according to the HL object, observers still react normally between the firing and being hit, time will pass forwards and the HLO will arrive sometime after, even a tiny fraction of sometime, being launched. If anything, the target suffering from heavy time dilation is only hit faster than one in a state of lower dilation and a firer in a high dilation state only sees the impact result faster. None of this implies that the effect would occur in an instant nor does it imply that some combination of of high dilation actor and HLO induces the HLO to break causality. It all just happens really really fast from the HDA's perspective and since it is an HLO it all happens really really fast from anyone's perspective (because, let's face it, in the grand scheme of things, light is really freaking slow).

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Mjolnir
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Re: Page 90

Post by Mjolnir »

Cy83r wrote:However, if both parties are experiencing roughly the same rate of dilation then... aren't they still reacting at the same speed and thus hit each other at roughly the same rate of delay?
You're thinking about the setup like they're actually moving at some definite velocity with respect to a fixed rest frame. There's no fixed rest frame.

Cy83r wrote: After all, the article said, IIRC, they were hitting each other instantly after firing, but FTL does not necessarily imply instant transmission from point to point, just that the transmission is faster than the propagation of light, like some sort of very odd hypersonic boom mixed with a doppler effect.
That is only to simplify things a bit. Non-instantaneous FTL signaling is equivalent to signaling limited by the speed of light for a distance followed by instantaneous signaling.

Cy83r wrote:Actually, this is very much like hypersonic objects, targets are being hit by hyperlight particles, which means that they are hit before they would ever have a chance to register to oncoming object let alone the actions leading up to whatever launched said HL object at them. Even if time is wonkified according to the HL object, this effect would only occur according to the HL object, observers still react normally between the firing and being hit, time will pass forwards and the HLO will arrive sometime after, even a tiny fraction of sometime, being launched. If anything, the target suffering from heavy time dilation is only hit faster than one in a state of lower dilation and a firer in a high dilation state only sees the impact result faster. None of this implies that the effect would occur in an instant nor does it imply that some combination of of high dilation actor and HLO induces the HLO to break causality. It all just happens really really fast from the HDA's perspective and since it is an HLO it all happens really really fast from anyone's perspective (because, let's face it, in the grand scheme of things, light is really freaking slow).
Again, you're assuming a fixed rest frame, with a universal clock that time dilation is measured in reference to. Relativity doesn't work that way.

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icekatze
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Re: Page 90

Post by icekatze »

hi hi

Simply put, from the perspective of both duelists, time for their opponent is moving slower than it is for themselves. This is not a paradox -at least it isn't up until the point where you go faster than light.

graphical explanation

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Cy83r
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Re: Page 90

Post by Cy83r »

icekatze wrote:Simply put, from the perspective of both duelists, time for their opponent is moving slower than it is for themselves.
Wait, no, that can't be right, from the perspective of someone at a high time dilation, everything else moves faster... doesn't it?

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Mjolnir
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Re: Page 90

Post by Mjolnir »

Cy83r wrote:
icekatze wrote:Simply put, from the perspective of both duelists, time for their opponent is moving slower than it is for themselves.
Wait, no, that can't be right, from the perspective of someone at a high time dilation, everything else moves faster... doesn't it?
No. Leaving out the complexities of GR and gravitational time dilation, time dilation isn't absolutely high or low, it is a function of relative motion between observers. Events in another frame can appear to move faster than normal, but this is a result of doppler effects, not time dilation...time dilation always means clocks in the other frame run slower.

Nemo
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Re: Page 90

Post by Nemo »

Cy83r wrote:
Nemo wrote:They've tested time dilation multiple times. It works.
Never said it didn't.
That part was for junk. Left out mah quotes.

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Cy83r
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Re: Page 90

Post by Cy83r »

Mjolnir wrote:
Cy83r wrote:
icekatze wrote:Simply put, from the perspective of both duelists, time for their opponent is moving slower than it is for themselves.
Wait, no, that can't be right, from the perspective of someone at a high time dilation, everything else moves faster... doesn't it?
No. Leaving out the complexities of GR and gravitational time dilation, time dilation isn't absolutely high or low, it is a function of relative motion between observers. Events in another frame can appear to move faster than normal, but this is a result of doppler effects, not time dilation...time dilation always means clocks in the other frame run slower.
...wait, time dilation is a function of acceleration, correct? What happens when a ship stops accelerating? No, that can't be right, the potential energy is still there so you'd still be under the effect, or at least you should. Fuck it, I don't understand these physics anymore.

fredgiblet
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Re: Page 90

Post by fredgiblet »

Velocity. Not acceleration.

Nemo
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Re: Page 90

Post by Nemo »

Also have to remember that these causality breaking events don't just happen at relativistic velocities, they're just easier to conceptualize. ALL time is relative to the frame: time at sea level is different from time in Denver because of minute differences in gravity. Time at the equator is different from time at the north pole because of different velocities. Time for you is different than it is for the computer in front of you, just not enough to notice. Anything that travels faster than light side steps time. Anything side stepping time side steps cause.

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Re: Page 90

Post by discord »

on 'absolute rest frame' if C truly is a constant, and the fastest possible velocity in a given direction is C, then by definition you HAVE a absolute rest frame, at absolutely zero velocity....but since physics guys keep saying that it's a matter of perspective....can you out accelerate a photon by C? no you can't, ergo, there is a rest frame, it's just not easily measured.

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Cy83r
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Re: Page 90

Post by Cy83r »

Nemo wrote:Also have to remember that these causality breaking events don't just happen at relativistic velocities, they're just easier to conceptualize. ALL time is relative to the frame: time at sea level is different from time in Denver because of minute differences in gravity. Time at the equator is different from time at the north pole because of different velocities. Time for you is different than it is for the computer in front of you, just not enough to notice. Anything that travels faster than light side steps time. Anything side stepping time side steps cause.
nnn, no, not to my understanding, things either slow down or speed up, there is no sidestepping of causality

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Mjolnir
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Re: Page 90

Post by Mjolnir »

discord wrote:on 'absolute rest frame' if C truly is a constant, and the fastest possible velocity in a given direction is C, then by definition you HAVE a absolute rest frame, at absolutely zero velocity....but since physics guys keep saying that it's a matter of perspective....can you out accelerate a photon by C? no you can't, ergo, there is a rest frame, it's just not easily measured.
It's c, lower case. And the fastest possible velocity in all directions is always c, in all inertial frames. Measure the speed of light in all directions from here on Earth...c. Accelerate until you're flying away from Earth at 0.999c and repeat the measurements...it's still c, in all directions.

Cy83r wrote:nnn, no, not to my understanding, things either slow down or speed up, there is no sidestepping of causality
And your understanding has been shown to be incomplete. Preservation of causality requires that signals don't travel faster than c. Velocities larger than c are as nonsensical to the universe as velocities lower than zero. There's completely-theoretical particles that travel faster than c, but they are only made consistent with observations and theory by restricting their interactions with normal matter so they can't actually transmit information faster than c.

Nemo
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Re: Page 90

Post by Nemo »

so they can't actually transmit information faster than c.


Which is functionally the same as not being faster than c anyway.

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Cy83r
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Re: Page 90

Post by Cy83r »

Mjolnir wrote:
discord wrote:on 'absolute rest frame' if C truly is a constant, and the fastest possible velocity in a given direction is C, then by definition you HAVE a absolute rest frame, at absolutely zero velocity....but since physics guys keep saying that it's a matter of perspective....can you out accelerate a photon by C? no you can't, ergo, there is a rest frame, it's just not easily measured.
It's c, lower case. And the fastest possible velocity in all directions is always c, in all inertial frames. Measure the speed of light in all directions from here on Earth...c. Accelerate until you're flying away from Earth at 0.999c and repeat the measurements...it's still c, in all directions.
That's precisely the understanding it I was talking about.
Cy83r wrote:nnn, no, not to my understanding, things either slow down or speed up, there is no sidestepping of causality
And your understanding has been shown to be incomplete. Preservation of causality requires that signals don't travel faster than c. Velocities larger than c are as nonsensical to the universe as velocities lower than zero. There's completely-theoretical particles that travel faster than c, but they are only made consistent with observations and theory by restricting their interactions with normal matter so they can't actually transmit information faster than c.
Shown, no; admitted, yes. I would expect you to know the difference between 'I don't understand' and 'You're right, I'm wrong'. Now let's forget this entire thing because I'm going to wind up committing bannable offenses if we continue.

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Razor One
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Re: Page 90

Post by Razor One »

Yeah, I think we should drop the physics angle as it's derailing the thread and braining my damage. I've been trying to wrap my damage around relativity since high school and it's been doing my head in trying to get a clear picture of how it works.
Cy83r wrote:
Also, you take Kendo classes? You win.
Heh, I suck actually, I'm still in the tutorial Kendoka classes, though we're starting to merge with the main group. The upperclassmen set a really brutal pace compared to what we're used to... though I guess that's to be expected when compared to us newbies. They might even entrust us with bogu someday!

Tangenitally on topic... I do wonder sometimes how certain Earth sports, martial arts in particular, would be viewed through Loroi eyes.

Especially Kendo... especially when the Kiai'ing starts up.

Yes, I have a vested interest :P
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Cy83r
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Re: Page 90

Post by Cy83r »

Razor One wrote:Tangenitally on topic... I do wonder sometimes how certain Earth sports, martial arts in particular, would be viewed through Loroi eyes.

Especially Kendo... especially when the Kiai'ing starts up.

Yes, I have a vested interest :P
Yeah, I'm wondering myself when the whole aspect of sanzai "conversing truth without words" and the human ideal of words of honor gets deeply discussed between Alexander and Still Storm, or maybe just he and Beyrl hash it out for exposition's sake.

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Arioch
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Re: Page 90

Post by Arioch »

The Japanese "martial arts," and Bushido itself, were all developed after the period in which the samurai actually fought wars. So, like most "martial arts," they have almost no military value. Some of them may have been useful for fighting duels, but even that is doubtful.

On the one hand, the Loroi also had peacetime periods where the warrior class probably had little better to do with their time than develop flowery "arts" fighting styles. But after 25 years of total war, I doubt such styles still receive much attention. So Loroi observers of Terran martial arts would probably view them with mixed reactions of nostalgia and amusement.

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