Who thinks Faster Than Light travel is possible?

[Swank]

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.

They are two light years apart from the observation of the station. One ball has no influence on the other.

If you aimed each ball at targets 1ly away in each direction and 2ly total, 2 years after launch you would see the simulataneus impact. (Ball out, light of impact back.)


This really isn't a relativity problem. It is just the fact that if you add two unrelated events up and divide by time, the number is larger than the velocity that objects can travel. It is silly to conflate observation with velocity.

 

[sciwriterPark]

i think the first thing we have to overcome is how to generate tremendous energy in a small form factor.

 

[Christine Wheelwright]

If you aimed each ball at targets 1ly away in each direction and 2ly total, 2 years after launch you would see the simulataneus impact. (Ball out, light of impact back.)

I agree with that. But my point is that, to me as the observer, they exist where I see them. If I check them one year after releasing them they are half a light year away as per my observation. Any effect they have on me (their light or heat reaching me, their gravitational effect on me) demonstrates them to be half a light year away in my present moment.

 

[Daysman]

AFAIK, we've not observed any massive objects actually moving FTL?

They'd need to interact with photons we can see, of course, but once discovered we'd have to handle not agreeing the order of events with anyone ever again...

I'm not sure why any future theory would address this topic directly, or expose any loophole that might allow it.

I'm guessing someone will prompt a suitable AI at some point and we'll suddenly have two dozen solutions, most of which are very bad ideas, except we won't know which ones or why... not at first.

As for playing with spacetime, that's really a topology thing isn't it?

I need food.

 

[Swank]

I agree with that. But my point is that, to me as the observer, they exist where I see them. If I check them one year after releasing them they are half a light year away as per my observation. Any effect they have on me (their light or heat reaching me, their gravitational effect on me) demonstrates them to be half a light year away in my present moment.

I'm not sure I see the relevance. You might not be able to see a train in a tunnel, but it's there.

 

[Christine Wheelwright]

I'm not sure I see the relevance. You might not be able to see a train in a tunnel, but it's there.

I think we are probably on the same page. My point is that after a year I check on the ball and it is half a light year away. That is what I see. That is what I measure by any means possible. I feel a gravitational field from it confirming that it is half a light year away. Every physical property or measurement or observation tells me it is half a light year away. That is my reality! You say it is actually one light year away and I am looking six months back in time, which is perhaps valid. And I notice the new telescope guys say we are looking at galaxies billions of years ago (rather than using the phrase 'billions of light years away'). That's all good.

The other thing worth mentioning is that the velocity of the object can be ascertained by looking at the dopler shift in the frequency of the light it emits (in case the object we are looking at is not the ball we threw one year ago....the velocity of which we know).

 

[Christine Wheelwright]

And in answer to the original question - not a chance we will ever travel faster than light. I doubt we will get manned travel outside the solar system (and, indeed, what would be the point if we can't reach the stars?). I see the physics as a hard limit, I'm afraid.

 

[psikeyhackr]

I do not think it is possible, I just hope that it is not impossible.

It took about 200 years to notice that the precession of Mercury showed that something was wrong with Newtonian physics. It was not until the 1990s that someone figured out that the increasing rate of expansion of the universe demonstrated that Poul Anderson's Tau Zero was fundamentally flawed.

As long as there is unexplained physics out there then there can be hope. But if we can get to 20% of light speed, extend human life spans to 300 years and come up with some form of suspended animation then infinite possibilities cannot be excluded.

Ad Astra!

Aliens be damned! Argh!

To be trapped in this solar system for the next 100,000 years is a dismal prospect.

 

[Overread]

And in answer to the original question - not a chance we will ever travel faster than light. I doubt we will get manned travel outside the solar system (and, indeed, what would be the point if we can't reach the stars?). I see the physics as a hard limit, I'm afraid.

The thing is physics is only a hard barrier as we understand physics today.

Don't forget go back in time and at various points many technologies we have today had hard barriers in logical thinking at the time.

Things like jumbo jets or rockets were impossible. The idea that you could fly not just 1 person but hundreds at once; or go around the world in only 3 days (Concord) etc... Even a lot of basic things like mobile phones, the internet, computers and such were all impossible at various points in time. All with very sound logical thinking for the time.

That's the key with science. It can't really tell you what is or isn't possible. It can only tell you what is and isn't possible within the context of understanding today and what might be within the understanding of tomorrow. But next week; next month; next year - the further off you try and forecast the more wildly inaccurate it becomes.

 

[Swank]

The thing is physics is only a hard barrier as we understand physics today.

Don't forget go back in time and at various points many technologies we have today had hard barriers in logical thinking at the time.

Things like jumbo jets or rockets were impossible. The idea that you could fly not just 1 person but hundreds at once; or go around the world in only 3 days (Concord) etc... Even a lot of basic things like mobile phones, the internet, computers and such were all impossible at various points in time. All with very sound logical thinking for the time.

That's the key with science. It can't really tell you what is or isn't possible. It can only tell you what is and isn't possible within the context of understanding today and what might be within the understanding of tomorrow. But next week; next month; next year - the further off you try and forecast the more wildly inaccurate it becomes.

80 years ago some engineers thought the sound barrier would destroy aircraft.

 

[J Riff]

Not 'faster' but it amounts to the same thing, so yeah.

 

[THX1138]

One problem I see is that as a ship travels closer to light speed, the entire electromagnetic spectrum in the surrounding space will become more coherent: a full spectrum laser the diameter of the ship's width cross section. That's a lot of energy to absorb.

We know that science today has made materials that self-generate low level magnetic fields, and these fields can be amplified with by a low amp external power source. So, cover the entire ship with a front plane highly/absolute reflective surface that also self-generates a total'ish refractive field above it, that can be amplified by the ships power source to refract the entire known electromagnetic spectrum (+- for unknown frequencies).

This would allow the ship the 'slip' into the coherent wall of light, thus closer to LS.
Now the view from inside the ship looking out would be...as close to absolute black as you could get. No star streaks or cloud tunnels. The entire/close to entire electromagnetic spectrum is being bent around the ship. Thus, darkness.

Less friction = closer to the speed of light. With this in mind about this type of system, you would need to travel the path of less electromagnetic spectral friction. The darker the better, full spectrum wise.

I agree with the near light limit theory because just as the mass of water limits the speed of fish, subs, torpedoes, UWLBM. The same is for the speed of sound and light too. That is where material science came in for both. The same is for LS.

Science fiction plus a positive result from a science theory could become science fact.
Until then, this is both theory and fiction!

 

[Astro Pen]

FTL, I think, will always be impossible. As will 'gravity shields' which are also based on flawed thinking.

So- what is possible for future technology to deliver?
Again I suggest that we think outside the mental trap of of our single point biology .
Once we are fully digitised and consist of a pure information structure, no longer facing 'three score years and ten', the light barrier will cease to be of such great concern.
We can be both eternal and duplicable (which leads to a whole philosophical discussion on where the "self" is. But that is for another day.

(Stross's Accelerando is a quite transformative SF read in this regard.)

 

[Harpo]

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.

How about if we built a gigantic particle accelerator all the way around the sun (like in Ringworld or whatever) so the particles could be sped up to almost lightspeed, and then make two collide, producing (my hypothesis, unless others have also said this) tachyon particles.

Probably nonsense, of course

 

[Swank]

How about if we built a gigantic particle accelerator all the way around the sun (like in Ringworld or whatever) so the particles could be sped up to almost lightspeed, and then make two collide, producing (my hypothesis, unless others have also said this) tachyon particles.

Probably nonsense, of course

If tachyon's existed, this would be a great plan. Why not just build the warp field using dilithium crystals? Or get the computer to calculate the jump to lightspeed so we don't fly through any stars? Or travel in a police call box?

 

[TheEndIsNigh]

So....

Faster than light;-

The moon is orbiting the earth happily shining down on us poor peasants.

If the earth were to suddenly disappear the gravitation force holding the moon would also no longer exist.

Does anyone think that the moon would hang around for a few seconds to travel in a straight line until the speed of light caught up with it.

No it would immediately whip off at a tangent instantaneously.

Yeah but that can never happen I hear you say. You can't just disappear the earth so it's a pointless examlpe you say.

But we're in the world of thought experiments here. If old the E=mc2 guy can think up experiments that can't be implimented that prove his theory surely I can have a bash too.

In any case the Earth is disappearing from it's current position every pica-second as it waltzes round the sun, galaxy, universe.

I can't recall anyone saying the moon is dragging it's feet to catch up - otherwise it would be drifting away at an alarming rate.

as in

"Oooh look that blue thing I can't get away from is moving again. I'll wait for the speed of light to tell me about it and then catch up."

Two hundred and fifty miliseconds later...

"HEY! Earth, wait for me!"

 

[Wayne Mack]

Another thing to consider is that the discussion is really about much faster than the speed of light. Correct me if I'm wrong, but Alpha Centauri is the nearest star at 4.3 light years away; a nearly 9 year round trip at the speed of light. Although there will be some sort of time dilation effect for those on the ship, a nearly decade long launch to return period seems like a large hurdle to overcome ("Let's go make some crop circles, it'll only take us nine years to do it."). To go much further requires speed at orders of magnitude greater than the speed of light.

 

[mosaix]

So....

Faster than light;-

The moon is orbiting the earth happily shining down on us poor peasants.

If the earth were to suddenly disappear the gravitation force holding the moon would also no longer exist.

Does anyone think that the moon would hang around for a few seconds to travel in a straight line until the speed of light caught up with it.

No it would immediately whip off at a tangent instantaneously.

Yeah but that can never happen I hear you say. You can't just disappear the earth so it's a pointless examlpe you say.

But we're in the world of thought experiments here. If old the E=mc2 guy can think up experiments that can't be implimented that prove his theory surely I can have a bash too.

In any case the Earth is disappearing from it's current position every pica-second as it waltzes round the sun, galaxy, universe.

I can't recall anyone saying the moon is dragging it's feet to catch up - otherwise it would be drifting away at an alarming rate.

as in

"Oooh look that blue thing I can't get away from is moving again. I'll wait for the speed of light to tell me about it and then catch up."

Two hundred and fifty miliseconds later...

"HEY! Earth, wait for me!"

In thought gravity operated at the speed of light. If so the ‘moon would hang around’. Not sure how long for.

 

[Mon0Zer0]

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 case you're not joking:

C doesn't apply to relative speed as each is independently travelling at light speed. Both particles are moving in opposite directions at the speed of light. Each particle has its own inertial reference frame.

"You can ask how fast the distance between them is increasing in a particular inertial reference frame, and the answer will indeed be that it's increasing at 2c, but the light-speed limit only applies to things like particles and information, it doesn't apply to concepts like "the distance between two objects"."

Reference: Light in opposite directions

Edit: Christine and Alai beat me to it

Your gaze is moving between photons arriving at your eyes, not between the galaxies.

I love the idea of your eye actually moving from one object to another as you look at them - as if you were touching them with your eyeball.

 

[paranoid marvin]

And in answer to the original question - not a chance we will ever travel faster than light. I doubt we will get manned travel outside the solar system (and, indeed, what would be the point if we can't reach the stars?). I see the physics as a hard limit, I'm afraid.

I agree that human beings in their current form are extremely unlikely to travel outside of our solar system; if this is the case, we therefore will not travel faster than the speed of light.

On the other hand, I do believe we have not come to the end of our scientific discoveries of the universe. It's could be that the next discovery will be yet another one that makes us have to re-position our understanding of what and what isn't possible. As I mentioned earlier, there is so much in the universe that has yet to be discovered, that dismissing the theoretical possibility of travelling faster than light would be an over-estimation of our current understanding.

There is so much space out there, that who knows what could be whizzing around undetected, perhaps travelling at many times the speed of light. It's entirely possible that when you reach a certain velocity, the laws and physics of the universe are turned on their heads.

Apparently the universe is expanding, but also there (apprently) is no 'edge' to it. How can that be? If there was no edge, we would either be going around in circles or the universe would be (somehow) expanding into itself. We are faced with so many anomalies and contradictions that almost anything is both possible and impossible at the same time. The more we are told, the more I think that Douglas Adams had a better understanding of the meaning and workings of the universe than all of the astronomers and scientists combined.