Who thinks Faster Than Light travel is possible?

[Serendipity]

Ever since Miguel Alcubierre published his paper saying that there is a theoretical solution to Einstein's General Relativity equations that allow FTL travel, the prospect of it eventually becoming reality has been dangled in front of our noses.

Who here thinks if can become a reality and why?

 

[Swank]

I think it is possible, but only because there are other solutions to paradox other than a prohibition on FTL.

Alcubierre seems to be offering to make one thing possible by violating a different fundamental law.

 

[Venusian Broon]

Ever since Miguel Alcubierre published his paper saying that there is a theoretical solution to Einstein's General Relativity equations that allow FTL travel, the prospect of it eventually becoming reality has been dangled in front of our noses.

Who here thinks if can become a reality and why?

At the moment absolutely not. Because all such solutions are so astronomically unphysical both in scale and in the conditions required. Furthermore, just because you can solve a mathematical equation, that models the universe, does not mean its solution is real. Finally, we know that relativity can't be totally right.

So come back when (or if) we crack quantum gravity or some deeper theory of reality - a new theory of everything may allow FTL by revealing something new about the universe that lets us 'go warp speed' (or may just rule out all these ideas anyway and we remain sub-FTL.) Or perhaps when (and again, if!) we can start to easily manipulate matter and energy on the scale probably billions of times more than our civilisation does today.

 

[Wayne Mack]

I'm not sure if this is a direct answer, but this is an interesting tidbit I found in researching a story. The universe expands faster than the speed of light. My physics-fu isn't strong enough to understand the explanations, but here is one link: How Can the Universe Expand Faster Than the Speed of Light?

 

[Swank]

I'm not sure if this is a direct answer, but this is an interesting tidbit I found in researching a story. The universe expands faster than the speed of light. My physics-fu isn't strong enough to understand the explanations, but here is one link: How Can the Universe Expand Faster Than the Speed of Light?

Two beams of light traveling in opposite directions are moving away from each other at twice the speed of light.

I can move my gaze between stars many light years apart at thousands of times the speed of light.

 

[Robert Zwilling]

I believe it is likely that a lump of matter physically accelerated faster than the speed of light would change into something else, probably no way to get it back.

Then there the ultimate problem solver of the proverbial wormhole, which connects sections of space together by utilizing folds in space. It sounds practical but you still have to travel long distances inside and outside of the worm. To be practical there would have to be wormholes all over the place. There is still the problem of how folded space could be. Although if it did get you anywhere it would be something, unless it ended up in the middle of nowhere.

This brings up multiple planes of existence which I do believe in and figure there are different rules governing how things work in them. Would it support physical FTL, I don't know, but probably not. Which brings up the idea of transporting matter or an energy pattern by replicating the exact pattern of an object and its place in space such that the space around it represents another location in space. An advanced form of spooky action at a distance. It would be recreating a pattern in another location which would be everything it was in the original location.

Would consciousness also be able to travel the same way. Probably not, as it is just a recreation of a physical pattern that gets transported. This is where it gets whimsical. The body could either arrive with a blank state for memories or the memories could also be physically copied such that the person would know what was going on. If the person didn't know what was happening, they would need a set of instructions to tell them what was happening.

Another scenario in which FTL is not needed is one in which stars are not so far away from each other or where multiple planets of the same solar system have life on them which makes traveling between them not impossible. Traveling hundreds of years to get to another planet sounds like a long time but if the situation did exist I'm sure someone would try it. If it was multiple stars close to each other I guess they would have to be fairly small to minimize interactions between the stars that could make life unlikely. Or maybe it would promote the existence of life if there were interactions between the stars.

 

[alai]

Two beams of light traveling in opposite directions are moving away from each other at twice the speed of light.

I'm afraid not. Their relative speed isn't even strictly definable, as there's no "photon's eye view" available in formal theory, much less to any experimenter. But consider a notionally feasible limiting sort of case. Two spaceships are moving apart, each at 0.9c (or 0.99c, or 0.999c, or any such value you like). They're separating at 1.8c, right? (Or 1.98, 1.998...) Nope! Still less than c, from either of their frames of reference.

I can move my gaze between stars many light years apart at thousands of times the speed of light.

Sure, but your "gaze" in this sense is a non-physical abstraction. No matter, energy, or information is "moving" at that speed.

I'm not sure if this is a direct answer, but this is an interesting tidbit I found in researching a story. The universe expands faster than the speed of light. My physics-fu isn't strong enough to understand the explanations, but here is one link: How Can the Universe Expand Faster Than the Speed of Light?

One way of thinking of it is like this: imagine your "universe" is a gigantic (3D) balloon that someone's constantly inflating. Now imagine you're travelling in a teeny-tiny (2D) car over the balloon's surface. Everywhere there are cute little "MAXIMUM SPEED 55mm/h! ENFORCIBLE BY NATURAL LAW!" signs. (Drawn on the roads, of course, because 2D, and as we don't want to start sticking pins in the balloon.) Naturally as you're a law-abiding citizen and don't want to vanish in a puff of causality, you adhere strictly to this limit. But! As measured from a large distance away, due to expansion of the balluniverse, you could actually be going faster.

 

[Swank]

I'm afraid not. Their relative speed isn't even strictly definable, as there's no "photon's eye view" available in formal theory, much less to any experimenter. But consider a notionally feasible limiting sort of case. Two spaceships are moving apart, each at 0.9c (or 0.99c, or 0.999c, or any such value you like). They're separating at 1.8c, right? (Or 1.98, 1.998...) Nope! Still less than c, from either of their frames of reference.

I'm afraid so. Like my gaze example, you can add up the movement of multiple things moving away from you and make a statement about the velocity of their separation. But the point is that separation (like the expansion of the universe) isn't a thing. It is an abstraction. The expansion of the universe is below c. The expansion in two different directions added together can be more can c.

No different than claiming two planes going in opposite directions at 400 miles and hour are breaking the sound barrier because the are going away from each other at 800 mph.

 

[Christine Wheelwright]

Two beams of light traveling in opposite directions are moving away from each other at twice the speed of light.

I can move my gaze between stars many light years apart at thousands of times the speed of light.

In my frame of reference I might have light moving in one direction (at the speed of light) and light moving in the opposite direction (at the speed of light) as you describe. However, in the frame of reference of the first beam, the second beam is not moving away from it at twice the speed of light. It is simply moving away at the speed of light. This is modelled by the Lorentz transformations. Nothing can exceed the speed of light in any frame of reference.

[EDIT: In other words, what alai said!......You beat me to it!]

 

[paranoid marvin]

I suspect that if the human race is around long enough to travel outside of our galaxy (assuming we can even leave our solar system), a lot of the things that we take as 'facts' will be as accurate as the scientific knowledge will held to be irrefutable 1000 years ago. In fact it could only take one alien spacecraft landing landing in Central Park tomorrow to turn our scientific knowledge on it's head.

Granted we have come along way in the last 1000 years, and the probes and satellites that we have sent out into space (along with the development of computers which can calculate in seconds what would have taken a lifetime) have left us in an infinitely stronger position to determine facts, but we are still trying to judge the mysteries and mechanics of the universe from a tiny planet in a remote part of the galaxy.

I do think that it's likely that there are ways of travelling from point A to point B faster than the light is able to. Whether that means 'bending' space, slowing down time, or something else I do not know. Does that mean moving at faster than the speed of light? In a way yes, in a straight-line race, then probably no. But I do hope and suspect that there is far, far more to the universe than we could ever comprehend or imagine even in our wildest dreams. It's just too darn vast a place for that not to be the case.

 

[Swank]

In my frame of reference I might have light moving in one direction (at the speed of light) and light moving in the opposite direction (at the speed of light) as you describe. However, in the frame of reference of the first beam, the second beam is not moving away from it at twice the speed of light. It is simply moving away at the speed of light. This is modelled by the Lorentz transformations. Nothing can exceed the speed of light in any frame of reference.

[EDIT: In other words, what alai said!......You beat me to it!]

I was demonstrating what was in the example about the expansion of the universe from the reference frame of earth. It is a legitimate reference frame, and nothing more than that. We can quite definitely observe things moving away from us in two directions that sum to more than c.

 

[alai]

Which brings up the idea of transporting matter or an energy pattern by replicating the exact pattern of an object and its place in space such that the space around it represents another location in space. An advanced form of spooky action at a distance. It would be recreating a pattern in another location which would be everything it was in the original location.

Would consciousness also be able to travel the same way. Probably not, as it is just a recreation of a physical pattern that gets transported. This is where it gets whimsical. The body could either arrive with a blank state for memories or the memories could also be physically copied such that the person would know what was going on. If the person didn't know what was happening, they would need a set of instructions to tell them what was happening.

To take those in reverse order, imagine the 'copying' part with no 'transmission problem' aspect. Just a ma-HOO-sive USB-omega cable, let's say. If your copy lacks memories, it presumably also lacks the cognition to reconstruct them from written or verbal instructions! Unless there's some poorly understood mechanism wherein some of the processes of consciousness have a very different biological basis from others. Either way, if you're a brutal materialist reductionist like me, you'd ascribe that to a defect or deficiency in the copying process; maybe you replicated the 'hardware' but not its 'state', and we need a Jupiter-sized accelerator to scan the original you with sufficiently high resolution. If you're a Vitalist, Dualist, or other flavour of woo-salesperson, you might say this is evidence of the uniqueness of souls, Platonic barcodes, or the like.

But if the USB-omega method works, then surely it's in principle to generalise that to non-spooky action at a distance -- i.e., transmitting your copy at the speed of light.

Then there's the matter of whether you can transmit information via 'quangles'. If that's possible, and the previous step is too, then essentially spooky-teleportation is just a question of scaling that up to the required number of bits of information. Gets us into all sorts of causality problems, so you either have to invoke some sort of Cosmic Censorship, or dispense with that entirely.

I suppose there might be some sort of way of bundling the two things, so you can have human-scale spook-action without the intermediate steps, but I can't think offhand for what a rationale for that might be.

 

[Robert Zwilling]

The memories are physically recorded so theoretically they could be replicated along with the rest of the body. If the copying mechanism was really good, then copying everything including the soul might be possible. If the copying isn't that perfect, then perhaps the entity that makes the "I" part of the mind doesn't get copied. So now the body arrives, or is activated, in a remote location, complete with memories, as those can be copied, but only a loose way of attaching them together. Kind of like amnesia, you can walk, talk, eat, do complex things, remember some things, but you don't know who you are. You have all the facts, you're functional, but there are too many facts to have a clear idea of what to do next. That's where the instructions come in, the game plan so to speak. Based on how the memories are remembered, some people might just walk away from the job, ready to live their life the way they think they want to.

 

[Astro Pen]

If the universe is expanding then every beam of light is travelling away FTL as it surfs the wave of expansion. By a minute amount of course but it is.
If you subscribe to Guth's 'inflation' theory then outer galaxies are travelling away from us FTL right now.

Personally I regard cosmic inflation as 'the science of the gaps', a convenient elastoplast applied to awkward numbers in denial of general relativity.
Should it ever be proven physically possible with a replicable methodology then I will be on board for that FTL cruise on the good ship Paradox

 

[Overread]

Well so far we've almost got everything else from Star Trek including sliding doors!


Personally I always think its important to remember that science can only tell us what is impossible at the point in time at which science currently is. The future is unpredictable and many things thought impossible have been proven to be possible through the steady advance of science and understanding.
At one time flying for humans was impossible, let alone flying hundreds of people at once; carrying the whole of a library on something no bigger than your finger; flying to the moon; actually looking at the surface of mars, the bottom of the ocean; predicting the weather. There are many many things that we do today, either personally or as a species which at one time were considered totally impossible to so outlandish they wouldn't even have conceived them as things to do.



Of course there's always a chance that things diverge down a different pathway - eg we forget about travelling faster than light because we discover a way to use wormholes to move around and thus negate the need for FTL travel options.

 

[Astro Pen]

ps
There is something else at play here, an anthropic* error. @Swank alluded to it earlier. We try to model the universe from a single point position. We can barely think outside that "you are here" box.
If you try to form an omniscient model of the universe rather than a point one, you will begin to reshape your perspective.
The other anthropic error is to use human reference points like extremely hot, incredibly fast, huge distance and such. A temperature simply is what it is and we should not ladle 'relative to me' adjectives on to science, because they are only relative to us, our speed of neuron firing and biological comfort zone.

*this may not be the right word use, but I think you know what I mean. Feel free to correct me.

 

[Ursa major]

The universe expands faster than the speed of light.

Apart from anything else, the universe isn't expanding inside the universe -- indeed, as far as we can tell, it's expanding into absolutely nothing at all, an absolutely nothing at all that has no dimensions of space or time) -- so is not constrained by the internal rules of the universe (one of which is that nothing can travel faster than c).

 

[Christine Wheelwright]

I was demonstrating what was in the example about the expansion of the universe from the reference frame of earth. It is a legitimate reference frame, and nothing more than that. We can quite definitely observe things moving away from us in two directions that sum to more than c.

Can we though? If I step outside my space station and throw one ball left at the speed of light and one ball right at the speed of light, how far apart are they when I observe them a year later? The answer is one light year not two Remember I am looking back in time six months but I cannot reason that the objects are two light years apart in 'their present'. In fact the objects see each other one light year apart (the first ball sees the second still at the space station....that image having traveled along side it). Thr second ball effectively does indeed exist at the space station in terms of it's effects on the first ball. And vice versa of course.

 

[Astro Pen]

Ah but what does my omniscient observer see?

 

[Christine Wheelwright]

Ah but what does my omniscient observer see?

Ah but the concept of an omniscient observer is meaningless. There is no such thing as a snapshot of the universe that shows the balls in my example two light years apart at a moment in time one year later. Because that particular moment only exists at the location where I threw the balls. Space and time are not separate parameters.