How long will it be until we have FTL?

[Stuart Mackey]

Well the points you make are all quite correct. The question of FTL is one that may well be impossible. However, I am not willing to beleive that a means of travel from one star system to another in a efficiant manner is impossible, as we simply do not know what the state of technology will be in 200 years from now, or 1000 years. What I think is arrogant is to presume that we are at the height of our abilties now which would rule out such a development in the future. I do know that it will not be some trekkie wetdream called warpdrive however.

Who said we were presuming to be at the height of our abilities? Our abilities will continue to grow, but they will grow within the limits of the universe's physical laws.

What I'm saying that it's more arrogant to presume that our abilities will eventually grow so limitless that we can eventually accomplish that which the entire universe has failed to accomplish in 15 billion years.

I see your point.

[His Divine Shadow]

Are we absolutely sure that the universe has not accomplished it?

Aanyhow, you can beat me with all the logic and evidence you got in this area and I'll still keep on hoping that we someday get it to work.

[Cpt_Frank]

Well, you can always hope, hell it would be fucking cool if we had FTL, but actually really believing that one time we'll get it, well....

[Crossover_Maniac]

Are we absolutely sure that the universe has not accomplished it?

Aanyhow, you can beat me with all the logic and evidence you got in this area and I'll still keep on hoping that we someday get it to work.

WOW!!! I've finally managed to find something that His Divine Shadow and I can agree on. Considering that scientists can't explain discrepancies in the orbital motion of stars in galaxies without relying on the possibility that either 90% of the matter in the universe has yet to be detected or modifying Newton's law of gravity, it's really premature to make any assumptions on the feasiblity of wormholes. Of course, it's more feasible that mankind can greatly increase human lifespan and develop technologies that allow for relativistic travel than it is of FTL travel, even by wormhole.

[Nick]

Wow - I'm surprised this thread has managed to get this far without anyone gushing about quantum entanglement. . .

Entanglement represents the concept of 'instantaneous action at a distance'. It seems to allow information to traverse space in zero time. However, the jury is still out on whether the results of current entanglement experiments represent actual FTL information transfer, or whether they represent hidden circular assumptions in the methodology, brought about by an incomplete understanding of the physics of fundamental particels. By and large however, most of the reports I've seen (from a couple of universities and publications like PhysicsWeb and Nature) have favoured the perspective that quantum entanglement is a real, observable effect (The methodologies and mathematics are pretty arcane - it's tough for a non-specialist to spot any overly optimistic interpretations of the results).

At the moment, the scientists investigating it are looking at it from two angles - first, trying to experiment with it to further demonstrate its validity, and secondly trying to figure out the mathematics behind it (and how it can be reconciled with Einsteinian mechanics). (Of course, there's a fundamental engineering problem they're playing with, too -assuming you manage to establish an entangled link, how the hell do you modulate the damn thing to transfer a message?)

For my money, if we're ever going to get FTL anything, it will be entanglement-based communication, not travel (along the lines of the ansible in Orson Scott Card's Ender novels).

http://physicsweb.org/article/news/5/8/20

[Nick]

http://www.mathpages.com/home/kmath521/kmath521.htm

Some of the maths related to quantum entanglement. See what I mean about it being impenetrable? I currently follow about a quarter of this - if I had a few days free to go over it (and flick through my university maths textbook), I might be able to get up to around 99%, but I still wouldn't be in a position to spot any mistakes or flawed assumptions.

Fun though - I want an ansible! (Or maybe a quantum computer. That would be cool, too).

[Smiling Bandit]

Oh, no! I'm goig into Nordom mode!

Probablility of cost-effective space travel unsewn. Retired variables not refined. The issue no longer euals total logik. Chance of success within 100 (+/-10) orbital revolutions: Slight.

[Colonel Olrik]

Actually, we won't need voyages of thousands years in starships. If we can achieve speeds close enough to c, and that is entirely possible, then the travel time as seen in the ship will reduce greatly.

It would be possible to travel even to other galaxies still during the lifespan of the crew.

The new colonies would be cut off forever in space and time from Earth, but the survival of the human race would be garanteed.

[Darth Wong]

Are we absolutely sure that the universe has not accomplished it?

We can't be absolutely sure of anything, as the creationists keep reminding us in their endless attempts to appeal to ignorance.

But we can say with confidence that we have observed millions upon milions of celestial objects, and without exception, they have all been moving at subluminal speed. This is drastically different from anything we've tried to achieve before, where there was simply no question that nature did it first.

Aanyhow, you can beat me with all the logic and evidence you got in this area and I'll still keep on hoping that we someday get it to work.

That's called "faith"

[Darth Wong]

Actually, we won't need voyages of thousands years in starships. If we can achieve speeds close enough to c, and that is entirely possible, then the travel time as seen in the ship will reduce greatly.

Travel close to c is within the laws of physics. However, in practical terms, the energy requirements make it hopelessly infeasible.

[Colonel Olrik]

Travel close to c is within the laws of physics. However, in practical terms, the energy requirements make it hopelessly infeasible.

Agreed, but that is a difficulty we may hope to overcome in the distant future.
At least, the theory behind is sound and does not require breaking comproved physical laws.

If I recall correctly, even the Orion project (NASA's thermonuclear blasts propelled ship) could reach 0.1c (granted, that's the same as nothing regarding relativistics effects).

It's the one thing I can imagine that would make long travels appealling (for the crew). Travel Times of a million years would require enormous ship / crew resources.

[General Trelane (Retired)]

Put me in the pessimist's camp. While I won't rule FTL travel or communication as being impossible, I do think that it's highly improbable.

It appears that most people are familiar with the problem posed by relativistic mass, but I'm surprised that there has only been one mention of the other big problem--causality. While we do not know whether the universe prohibits violations of causality, I won't believe it is possible until proven otherwise. FTL by definition would enable such violations. For the layman, here is a site that contains a decently simple explanation of the difficulties with FTL:

http://www.physics.purdue.edu/~hinson/f ... intro.html

Be ware of fringe science! While fringe science raises intriguing possibilities, please understand that many such scientists are competing for a limited pool of research funding...

[His Divine Shadow]

Are we absolutely sure that the universe has not accomplished it?

We can't be absolutely sure of anything, as the creationists keep reminding us in their endless attempts to appeal to ignorance.

But we can say with confidence that we have observed millions upon milions of celestial objects, and without exception, they have all been moving at subluminal speed. This is drastically different from anything we've tried to achieve before, where there was simply no question that nature did it first.

Aanyhow, you can beat me with all the logic and evidence you got in this area and I'll still keep on hoping that we someday get it to work.

That's called "faith"

I don't like where this is going...

[Imperial Federation]

Are we absolutely sure that the universe has not accomplished it?

We can't be absolutely sure of anything, as the creationists keep reminding us in their endless attempts to appeal to ignorance.

But we can say with confidence that we have observed millions upon milions of celestial objects, and without exception, they have all been moving at subluminal speed. This is drastically different from anything we've tried to achieve before, where there was simply no question that nature did it first.

I don't think the fact that we don't know everything about the universe is an appeal to ignorance.
Just as we can't say FTL travel is inevitable because of our limitless potential, we can't say that it's impossible because of what we've been able to observe up to this point.
I mean, FTL travel may be a pipe dream based on what we know now, but in the future nature may suprise us.

[Graeme Dice]

But we can say with confidence that we have observed millions upon milions of celestial objects, and without exception, they have all been moving at subluminal speed. This is drastically different from anything we've tried to achieve before, where there was simply no question that nature did it first.

Of course, it's real hard to observe an object moving greater than c, because the doppler shift will push the frequency of radiation into imaginary frequencies. (As long as the standard relativistic doppler shift equations hold at that speed.)

[EmperorChrostas the Cruel]

Crossover Maniac:

Your artificial wormhole would require field strenths so high, that the magnetic coils themselves would flow, like water under that kind of pressure. Action, reaction. The devise for producing the magnetic fields has to be strong enough to resist the forces they themselves are creating! Once again, slowly. The motor will never put more power to the wheels than the motor mounts can take. The mounts break, or the field coils tear themselvse apart, at the limit of their ultimate physical strenth. Metal becomes liquid, (like ice under the blade of an ice skate)at far less than the stress needed to make one of your wormholes.

I reiterate! ALL these FLT drives assume that, IF, you can use X amount of force, to manipulate Y kind of object, then, presto, FTL! Mathematical masterbation. (IF, the biggest two letter word in the dictionary!)

These "possibilities" are based on the assumption that the forces can be brought to bear on the problem. They are theoretical, and used to demonstrate mathematical points! It is POSSIBLE, that all the air in my room could fly up my ass, and my head will explode. In theory. The probability is so low, that, for MY purpose, it IS impossible!

All you need is some Unbelievium, and some Unobtanium, (BOTH of which are the ONLY material that meets the strenth reqirements to translate theory to practicality!) and you can build your FTL.

If I had four wheels, I'd be a bus!

Since I will never have four wheels, it is still THEORETICLY possible for me to become a bus, (should I get them SOMEHOW) but, it the REAL world, I will NEVER be a bus!

A more fitting question is, why is the idea that something is impossible so hard to stomach?

[Patrick Degan]

—you also forgot the necessary componnents of Ylludium Q36 and its base, Ylludium Phosdex, the Shaving Cream Atom.

[EmperorChrostas the Cruel]

Duck Dodgers, in the 24th 1/2 century, destroyed all but a beachball sized chunk of said Ylludium Q36 ore, scattering the remainder about the solar system.

Perhaps ACME could produce a graviton ore gathering gun, to scoop the scatted ore from the area. Alas, I fear the majority of the ore has expanded into the cosmos, spread too thin to ever reclaim.

[Darth Wong]

But we can say with confidence that we have observed millions upon milions of celestial objects, and without exception, they have all been moving at subluminal speed. This is drastically different from anything we've tried to achieve before, where there was simply no question that nature did it first.

Of course, it's real hard to observe an object moving greater than c, because the doppler shift will push the frequency of radiation into imaginary frequencies. (As long as the standard relativistic doppler shift equations hold at that speed.)

They should produce Cherenkov radiation. We have never observed Cherenkov radiation anywhere in the universe. Therefore, there do not appear to be tachyons anywhere outside of sci-fi. Ergo, the universe has probably not broken the light-speed barrier, and it is even more doubtful that we will.

[His Divine Shadow]

They should produce Cherenkov radiation. We have never observed Cherenkov radiation anywhere in the universe. Therefore, there do not appear to be tachyons anywhere outside of sci-fi. Ergo, the universe has probably not broken the light-speed barrier, and it is even more doubtful that we will.

Stop being so pessimistic, you make baby Jesus cry

[Nick]

Hey Mike, is there any way to give the man his 'L' already?

A more fitting question is, why is the idea that something is impossible so hard to stomach?

Because no-FTL rules out all sorts of cool shit. . . like star-hopping, massive inter-stellar empires and trade networks, meeting aliens, you name it. Me, I'm in the boat of "Gee, it'd be cool if FTL was possible, but I basically discount the possibility of it ever happening".

And while entanglement is cool (and kinda freaky), they're still demonstrating that what they think is going on, is what is actually going on. It's a fairly respectable haul from that to using the idea to transmit an FTL message (assuming the latter is possible at all).

[Grand Admiral Thrawn]

This is probably wrong:



Now, STL is possible (most obviously) and FTL is too. The problem is that to go from STL to FTL, you have to go SoL, which is impossible for anything with mass unless it has a googa load of energy.




So unless we go on a really good diet, or get a super duper mega ultra power sourse...

[Crossover_Maniac]

They should produce Cherenkov radiation. We have never observed Cherenkov radiation anywhere in the universe. Therefore, there do not appear to be tachyons anywhere outside of sci-fi. Ergo, the universe has probably not broken the light-speed barrier, and it is even more doubtful that we will.

Actually, Cherenkov radiation is a product of a particle traveling faster than the speed of light in the same medium. Cherenkov radiation has been observed in water shieldings of some nuclear reactors where the speed of light is 225,000 km/s (75% of the speed of light in a vacuum). The particles that are exceeding the speed of light in the medium forms Cherenkov radiation is formed from the electromagnetic radiation from displacing electrons along its path. Trying to find tachyons in intergalactic space by looking for Cherenkov radiation is ill-advised since Cherenkov radiation are formed in non-vacuum mediums where the speed of light is slower.

[Crossover_Maniac]

Crossover Maniac:

Your artificial wormhole would require field strenths so high, that the magnetic coils themselves would flow, like water under that kind of pressure. Action, reaction. The devise for producing the magnetic fields has to be strong enough to resist the forces they themselves are creating! Once again, slowly. The motor will never put more power to the wheels than the motor mounts can take. The mounts break, or the field coils tear themselvse apart, at the limit of their ultimate physical strenth. Metal becomes liquid, (like ice under the blade of an ice skate)at far less than the stress needed to make one of your wormholes.

According to the article, the strongest known magnetic fields are created in nuclear explosions (1E9-1E10 Teslas). However, the field strength needed to keep it open is only a few hundred. If, and I do mean 'if', such a wormhole is feasible, the magnetic field needed to generate it could be made by particle accelerator or some kind of implosion which is seen in inertia confinement fusion reactors only scaled up and maintained by powerful magnetic fields. Of course, this is all guess work and odds are, it'll just blow up in our faces. According to the Scientific American article How to Build a Time Machine, next generation particle accelerators should, in theory, create subatomic wormholes. This would be a test to see if wormholes have some basis in fact or is only a mathematical anomoly in the Theory of General Relativity.

[Crossover_Maniac]

This is probably wrong:



Now, STL is possible (most obviously) and FTL is too. The problem is that to go from STL to FTL, you have to go SoL, which is impossible for anything with mass unless it has a googa load of energy.

Actually, to get to the SoL, you need more than googa loads of energy, you need infinite energy, which is infinitely (pun intended ) more than googa load of energy. Of course, that's why lots of sci-fi series like to play around with space-time like warp drives and wormholes.