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Warp Drive May Be More Feasible Than Thought, Scientists Say

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Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#81

Post by pyre »

soup10 wrote: post #39
csense wrote: post #28

Earlier quoted context omitted.

1000 years is the blink of an eye compared to the lifetime of our galaxy or the amount of time it took life to evolve intelligence on Earth. There's no good reason to expect that humanity's age will be within 1000 years of an alien race's. Consider how little chance an army behind 1000 years technologically would stand against a modern army. Computer strategy games (I'm specifically thinking of Master of Orion and Ga…

It's absurd anyway. Advanced tech will(and already has, to an extent) put extremely destructive power in the hands of normal people. If we haven't learned to get along by then, we will certainly kill ourselves off.

It takes two to tango, so to speak. No matter how peaceable we are as a race, if the other guy has bigger weapons and is itching to use them, it might not make any difference.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#82

Post by nullc »

Ygg2 wrote: post #15
CWIZO wrote: post #10

As much as it pains me to say this, but I think we have to invent some more advanced weapons before we start poking our heads out of our galaxy. Don't get me wrong, this is fantastic and I'm all tingly from excitement (this is the first time I've read about warp drives in the context of real science) ... but like I said, taking a stroll trough the galaxy with our bombs and finding a hostile alien world. Well we'd be…

Seeing how if we use our warp drives to 'colonize' space, other creatures would have far more to fear from us than we from them (think Independence day with roles reversed). If a space faring species encounters non-space faring species, the one with warp is probably (not necessary) in the better position. Even without the weapons, FTL drive implies a magnitudes greater technology than anything a non-FTL race would ha…

> If a space faring species encounters non-space faring species, the one with warp is probably (not necessary) in the better position.

I read a fun science fiction novella once about a interstellar space faring species that invented their warpdrive whatchamacallit before their industrial revolution, no electricity, machines, etc. Flying medieval space galleons. And they were going about successfully conquering a bunch of similar or more primitive species. Then they encountered 20th century earth...

Wish I could remember the darn name.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#84

Post by jxcole »

nessus42 wrote: post #35

You can't have faster than light travel without violations of causality. And while the equations of General Relatively allow for universes where causality is routinely violated, the probability that we are in such a universe seems vanishingly small. E.g., just because you can violate causality does not mean that you can go back in time and kill your grandfather. If you were to try, something would stop you, as a univ…

A lot of people responding to this thread do not understand relativity. The OP is correct, the fundamental problem is causality, relativity and FTL do not mix. The common way of saying it is that you can have two of the three: FTL, causality, or relativity. You cannot have all three. Here is a very nice explanation of why:

http://thebestforumever.com/community/threads/tachyon-pistol...

Also, I've never understood how the Novikov self-consistency principle would work in reality. Causality violations can be a lot simpler than killing your grandfather. Say, for example, you set up a pool table with a pool ball and hit it through a time machine such that it went back in time and hit itself, making it miss the time machine? Would the pool ball be suddenly acted on by some invisible force? Would it explode? Would the universe just end? The whole scenario seems so implausible that addressing this theoretical concern is a lot more relevant than worrying about the energy levels required to manipulate space time.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#85

Post by spullara »

nessus42 wrote: post #61
dhughes wrote: post #55

Earlier quoted context omitted.

I think the "faster than light" part wording seems a bit off since from what I gather the point is not to go fast to get to a location but to get there through warped space-time. I imagine a 100 km long and 1km high brick wall, you're in the middle but want to get to the other side of the wall. Option #1 is to travel as fast as you can 50km to one end and then 50km back to the spot on the other side. Option #2 tunnel…

That's not the scenario described in the OP. The FTL drive described in the OP is a traditional "warp drive", that allows you to travel faster than light by moving the space around you faster than light, while you continue to travel slower than light within your rapidly moving space bubble. You're still effectively traveling faster than light, however, and you'd still be able to use this to travel backwards in time.

So, I haven't looked closely at it, but he does mention that your clock remains (almost) the same as an earth clock. That implies that there is no frame of reference that shows him traveling faster than the speed of light. I'm not sure that this can be used to violate causality.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#86

Post by chii »

pyre wrote: post #81
soup10 wrote: post #39

Earlier quoted context omitted.

It's absurd anyway. Advanced tech will(and already has, to an extent) put extremely destructive power in the hands of normal people. If we haven't learned to get along by then, we will certainly kill ourselves off.

It takes two to tango, so to speak. No matter how peaceable we are as a race, if the other guy has bigger weapons and is itching to use them, it might not make any difference.

Theoretically, it isn't possible to stop an advanced alien race that has mastered ftl travel from being able to destroy earth. There is this concept called relativistic bombardment - your "artillary" is set to travel so fast, that the light that comes off it only arrives moments before the actual shell, and thus, there is little to no warning. The only way to stop this sort of attack is a shield that is impenatrable. However, such a thing cannot exist, since the attacker has all the time they need to devise a shell that can penetrate the specific shield you intend to use.

Hence, the only safety you can guarentee is if you know your enemy don't know where you are, and thus can't aim the weapon. Otherwise, its impossible to stop an attack.

Now, conversely, humans knows this too, so it makes rational sense to attack first. Its MAD on a galactic scale!

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#87

Post by gotrythis »

I skimmed through the responses, which seemed to be all about the execution, with little or no discussion or debate questioning if this is a good thing or not.

Even more than the idea excites me, I hope this fails miserably. We're at the Avatar stage of our evolution, not Star Trek.

I think this says it best: (no affiliation) http://www.facebook.com/ResurrectingtheGoddess/posts/3960760...

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#88

Post by csense »

soup10 wrote: post #39
csense wrote: post #28

Earlier quoted context omitted.

1000 years is the blink of an eye compared to the lifetime of our galaxy or the amount of time it took life to evolve intelligence on Earth. There's no good reason to expect that humanity's age will be within 1000 years of an alien race's. Consider how little chance an army behind 1000 years technologically would stand against a modern army. Computer strategy games (I'm specifically thinking of Master of Orion and Ga…

It's absurd anyway. Advanced tech will(and already has, to an extent) put extremely destructive power in the hands of normal people. If we haven't learned to get along by then, we will certainly kill ourselves off.

> [With] Advanced tech...we will certainly kill ourselves off.

If the normal developmental pattern of technologically advanced races is T ~ a few thousands of years of continuous population increases due to technology [1], followed by a technology-caused extinction, it would neatly explain why we haven't met any aliens: Since T is a drop in a bucket compared to the time required for evolving intelligence, with high probability all the aliens close enough to us to send signals or spaceships gained intelligence more than T years ago, and have already killed themselves.

[1] The exact timing of the beginning of our technological development depends much on how you define "technological development." But it's fairly safe to say that T < 1 million years.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#89

Post by nessus42 »

spullara wrote: post #85
nessus42 wrote: post #61

Earlier quoted context omitted.

That's not the scenario described in the OP. The FTL drive described in the OP is a traditional "warp drive", that allows you to travel faster than light by moving the space around you faster than light, while you continue to travel slower than light within your rapidly moving space bubble. You're still effectively traveling faster than light, however, and you'd still be able to use this to travel backwards in time.

So, I haven't looked closely at it, but he does mention that your clock remains (almost) the same as an earth clock. That implies that there is no frame of reference that shows him traveling faster than the speed of light. I'm not sure that this can be used to violate causality.

>I'm not sure that this can be used to violate causality.

If you can transmit any information from point A to point B faster than light would travel from point A to point B in a vacuum, then there are inertial frames of reference in which the information arrived at point B before it left point A.

It's really just as simple and plain as that. You need consider nothing further once you know the above facts.

Re: Warp Drive May Be More Feasible Than Thought, Scientists Say

#90

Post by sentientbicycle »

nessus42 wrote: post #61
dhughes wrote: post #55

Earlier quoted context omitted.

I think the "faster than light" part wording seems a bit off since from what I gather the point is not to go fast to get to a location but to get there through warped space-time. I imagine a 100 km long and 1km high brick wall, you're in the middle but want to get to the other side of the wall. Option #1 is to travel as fast as you can 50km to one end and then 50km back to the spot on the other side. Option #2 tunnel…

That's not the scenario described in the OP. The FTL drive described in the OP is a traditional "warp drive", that allows you to travel faster than light by moving the space around you faster than light, while you continue to travel slower than light within your rapidly moving space bubble. You're still effectively traveling faster than light, however, and you'd still be able to use this to travel backwards in time.

I don't think you are understanding the concept here. http://en.wikipedia.org/wiki/Alcubierre_drive#Physics
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