Is faster-than-light travel possible?

August 26, 2005 2:17 PM

I've been somewhat obsessed with faster-than-light travel lately. Are there any scientists seriously studying thing such as the Alcubierre drive or other plausible, albeit exotic, ways to get from point a to point b without taking a million years? Is this something that just lacks the funding for any respected physicists to get involved? Surely there must be a department within NASA working on something a little more fun than sending a chemical rocket to a close planet.

I guess my question really is, if this were given an atomic bomb like research budget over several decades could we see results?

posted by geoff. to science & nature (17 comments total)

No way. Even if it's possible, it's still way out of our league. There is work being done on the subject, but it's not concretely "how do we go FTL", it's on relativity as whole, grand unified theories and that sort of thing.

The Alcubierre drive is a cute idea, but in no way more practical than just stating "we make a wormhole and travel through it" without specifying how to make such a wormhole.
posted by fvw at 2:25 PM on August 26, 2005

The book Hyperspace explains the difficulties and amount of energy required in an accessible fashion.
posted by null terminated at 2:26 PM on August 26, 2005

People always point to the sound barrier and say, "Look, this textbook said man will never fly past the speed of sound." But in fact my father's old engineering textbook was skeptical but open-minded on the topic and suggested that it might happen some day.

There's no analogy to the situation with FTL. In one theory of everything, FTL is theoretically possible - in the vicinity of giant black holes that would tear a human apart with their tidal effects long before that human could get close enough to take advantage of the theoretical loophole. Otherwise, no one's saying that people will ever travel faster than light. For such a thing to be theoretically possible, there'd have to be a whole new understanding of the way things work, in a direction where there is now not even an inkling of a theory.

Alpha Centauri, Tau Ceti and Sirius aren't that far away, though. There's no theoretical barrier to reaching A.C. in as little as four years, given enough delta-vee and a spacecraft that would support human life that long. I wish someone would give an atomic-bomb-sized, or at least an Iraq-war-sized budget to building one of these.
posted by ikkyu2 at 2:30 PM on August 26, 2005

if this were given an atomic bomb like research budget over several decades could we see results?

Richard Nixon declared a "War on Cancer", and signed an act, in 1971, that resulted, in the next 30 years, in government spending of more than $45 billion. And, as a review at the 30-year point observed, Total victory is nowhere in sight.

Which isn't to say that the money was totally wasted. What was spent on basic research was almost certainly valuable.

It only makes sense to spend large amounts of money only if disaster is imminent, or when (a) there are no major theoretical unknowns, and (b) there is at least a rudimentary understanding of what the end-technology will look like. FTL travel may never even get to (a), let alone (b).
posted by WestCoaster at 3:30 PM on August 26, 2005

As I grow older I begin to think the sci-fi of my youth is pure fantasy. We all want FTL to be possible, but currently the prevailing theory (that describes the universe very damn well) is that it is not. Untested theories to explain the conflict between general relativity and quantum mechanics may posit exotic FTL situations, but they are wholly unproven, and often only FTL in a very non-interesting way.

Hoping really hard that FTL is possible will not make it so. There is no credible reason to think that FTL is possible right now. Until we know otherwise, it seems to me that spending money on it would just be a waste.

It's a sad possibility that we may actually live in an almost unimaginably huge universe, which it is impossible for us to explore, due to our short life-spans and the c speed limit. We'd be lucky to see more than one solar system, actually. Such a bummer.

[And as much as sci-fi geeks don't want to, you have to look to the economics. Right now, there is no reason to travel beyond the earth, other than curiosity, let alone beyond the solar system. And without an economic impetus, it just ain't going to happen. Talk about the human explorer spirit all you want: the reality is that somebody has to write a huge check, and people don't do that without some economic benefit.]

That said, NASA does have a novel propulsion department. But they mainly focus on dreaming up ways to travel around the solar system that don't involve chemical rockets.
posted by teece at 4:38 PM on August 26, 2005

Nasa's Breakthrough Propulsion Physics Program
posted by 517 at 4:39 PM on August 26, 2005

i posted a longer post, hit submit and got a server error. I wont re-type it. This article gives a good overview. Its several years old but not much has changed - except maybe that wormholes look less feasible. You might like this take-away:

It is thought to be highly unlikely that engineers will be building space-ships with FTL drives in the foreseeable future, if ever, but it is curious that theoretical physics as we presently understand it seems to leave the door open to the possibility.

Regarding budgets, I think the time hasnt come yet. It'd be like funding the atomic bomb in the 1600's - too many things are not in place yet.
posted by vacapinta at 4:39 PM on August 26, 2005

Great link, vacapinta, thanks for pointing that out.
posted by teece at 5:45 PM on August 26, 2005

As with Nixon's war on cancer, perhaps there are just multiple major breakthroughs between here and FTL. When you're a caveman, you don't declare war on cancer. You try to develop the scientific method. Similarly, you don't tackle cancer when you've barely discovered DNA. I think the quest for a cancer cure is interesting. My impression is that we've discovered it's more and more a natural side effect to being a DNA based organism. Similarly, FTL is still beyond our conception because it clashes with certain instrinsic properties of the universe as we understand it.

The faster-than-sound thing is worth bringing up, but was there ever a mathematical proof that it was impossible? As I understand it, all theories about how to got FTL focus on areas where the normal laws of physics break down, such as near black holes. If you toss out the normal laws of physics, Barbara Bush could ride a Harley through a cheerio.

I think we need to focus first on more efficient, more powerful energy sources. Otherwise, we're never going to get close. Another worthwile question is whether we've found anywhere worth going?
posted by scarabic at 5:50 PM on August 26, 2005

Supposedly, 25% of the universe is dark matter, and 70% is dark energy, which means 95% of the universe is "we don't know, so we came up with a cool name." As far as we know right now, we can't travel faster than light. Until we figure it out, I'm sticking with The Right Stuff:

There was a demon that lived in the sky; and anyone that challenged him would die. They called it the Sound Barrier.

posted by kirkaracha at 10:38 PM on August 26, 2005

Talk about the human explorer spirit all you want: the reality is that somebody has to write a huge check, and people don't do that without some economic benefit.

This kind of thinking is a peculiarly modern illness.
posted by ikkyu2 at 11:17 PM on August 26, 2005

kirkaracha brings up an excellent point- As much as current scientific thinking "is this close" to understanding "everything", "everything" conveniently ignores a whole lot of stuff.

FTL has been demonstrated at very, very small (subatomic) levels, but requires an obscene amount of energy compared to the end result.

What, IMO, is an absolute prerequisite- and realistically possible- is a completely new self-sustaning source of massive energy. Beyond fusion. I think some combination of that plus advances in cryogenics/longevity are the more likely route toward interstellar exploration.

This kind of thinking is a peculiarly modern illness.

Absolutely not- I'd say that's been with us since the dawn of civilization. The chieftain has always made decisions based on "what's good for me and my tribe".
posted by mkultra at 8:10 AM on August 27, 2005

Yes, and if we'd relied on the chieftain for technological advances and the expression of the human exploratory spirit, all 6 billion humans would still be wearing rude loinclothes made from beaver pelts and living in that same damn cave.
posted by ikkyu2 at 10:54 AM on August 27, 2005

Who funded Columbus? Marco Polo?
posted by mkultra at 11:47 AM on August 27, 2005

Ferdinand's role would be one way to look at it. He wanted capital out of the vaults of Jewish goldsmiths and bankers and into the hands of contractors, shipbuilders, and shipfitters. If the ships went to the bottom of the sea, it'd still be good for Madrid's economy, as he knew well.

Same argument can be made about an American space program, btw, except it's not so hard on Jews.

But actually, Columbus infused his own journey with the intrepid explorer's spirit. Ferdinand and his ilk didn't have any of that at all; they sat around at home playing political games like 'keep the capital moving and send people to the bottom of the ocean.' (viz: Spanish Armada).
posted by ikkyu2 at 2:05 PM on August 27, 2005

With IE, kirkaracha's answer looks like this:

Supposedly, 25% of the universe is dark matter, and 70% is posted by kirkaracha at 10:38 PM PST on August 26 [!]

I just thought that was amusing.
posted by mr_crash_davis at 5:13 PM on August 27, 2005 [1 favorite has favorites]

The only other thing I would add to this is that the sound barrier and the "light barrier" have almost nothing in common. Their similarity is just about completely superficial.
posted by teece at 5:43 PM on August 27, 2005