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[MonkeyHead]

Would we be able to detect them anyway?

Common sense dictates you would send them in a manner detectable earlier in the timeline doesnt it?

Mind you, common sense seems a rare commodity, decreasing in availiability as time goes by...

[Necro910]

Either there are no messages from the future possible, or we have to build ourselves a machine to receive them and at that instant we get all knowledge ever obtained by the human race thereafter.

And then we create a time paradox and destroy all of reality.

That would be really dorfy though...

All in favor?

Aye

[Dsarker]

Would we be able to detect them anyway?

Common sense dictates you would send them in a manner detectable earlier in the timeline doesnt it?

Mind you, common sense seems a rare commodity, decreasing in availiability as time goes by...

If we don't know we're supposed to be looking for them......

[lemon10]

Would we be able to detect them anyway?

Common sense dictates you would send them in a manner detectable earlier in the timeline doesnt it?

Mind you, common sense seems a rare commodity, decreasing in availiability as time goes by...

Maybe there is no easy way to detect them, and the only way(s) possible require 21st century (or maybe better) technology to detect.
Or maybe we have already received them, but only a small group of people know about it.

[RedWarrior0]

What would be the implications? Nothing, potentially.

It would mean that c stays right where it is and there is some phenomenon which allows objects to surpass c without having infinite or imaginary mass.

Neutrinos might have complex mass; both a real and imaginary part.

[Gantolandon]

If we can harness it, possibly a way to send messages backwards in time

It doesn't work that way. Approaching faster-than-light speed wouldn't allow you to travel backward in time.

If you could, however, reach a star 4 light years away from the Earth in a second, theoretically you would be able to view Earth as it was 4 years before.

[Another]

Formally mass can be only either pure real or pure imaginary. In the complex case you have to be prepared to deal with complex length and time distances. In the simplest case of purely imaginary mass - the less energy a particle has - the higher it's speed. Neutrinos from supernova of 1987 had energy of about 1000 times less than CERN-OPERA ones and were travelling at a speed much closer to C than what is reported in this experiment. So it rules out the case of neutrinos having just some imaginary mass. (Common modern astrophysical models also favour cold relic neutrinos being slower than relativistic.)

By the way one of the interesting open problems with neutrino masses is that it can has Dirac mass, Majorana mass or contribution from both. Unfortunately it is too complex to explain here.

One of the minimum requirements to send backwards-in-time messages with a particle that is 1/100000 faster than C in all reference frames is to have one of the detectors travelling at γ=1/(1-v²/c²)^1/2>100000 relative to us. The OPERA detector has a mass of 1.766 ktons. Getting something like that to such ultrarelativistic velocity may very well be out of reach of humanity for the remaining of Solar system life out of general physical principles. Do not count on it for the next 200 years.

[thobal]

If we can harness it, possibly a way to send messages backwards in time

It doesn't work that way. Approaching faster-than-light speed wouldn't allow you to travel backward in time.

If you could, however, reach a star 4 light years away from the Earth in a second, theoretically you would be able to view Earth as it was 4 years before.

Bears repeating.

However, to an outside observer it might appear this way.

Take the example of one object moving towards the observer faster than the speed of light. Essentially, it would look like it was in two places at once. Now remembering that gravity travels at the speed of light...

[Criptfeind]

Now remembering that gravity travels at the speed of light...

Lol wut?

[Osmosis Jones]

If we can harness it, possibly a way to send messages backwards in time

It doesn't work that way. Approaching faster-than-light speed wouldn't allow you to travel backward in time.

If you could, however, reach a star 4 light years away from the Earth in a second, theoretically you would be able to view Earth as it was 4 years before.

Actually, yes it does;

In short, for any signal sent FTL in one frame of reference, another frame of reference can be found in which that signal actually traveled backwards in time, thus violating causality in that frame.

That means that if we shoot a couple of neutronino (herp a derp) sources and recievers off into space at an appreciable fraction of c (possible with project orion style rockets) and pass messages from us to one source to the next source and then back to us, we actually could send messages back in time. NOTE: We ourselves are not going back in time; only our messages are.

I should also point out, it would be insanely difficult if the best signal speed we can get is only 1.00002c. If we can get faster than that, then it gets a lot easier.

Trust me, I'm a scientist 

Spoiler (click to show/hide)

Formally mass can be only either pure real or pure imaginary. In the complex case you have to be prepared to deal with complex length and time distances. In the simplest case of purely imaginary mass - the less energy a particle has - the higher it's speed. Neutrinos from supernova of 1987 had energy of about 1000 times less than CERN-OPERA ones and were travelling at a speed much closer to C than what is reported in this experiment. So it rules out the case of neutrinos having just some imaginary mass. (Common modern astrophysical models also favour cold relic neutrinos being slower than relativistic.)

By the way one of the interesting open problems with neutrino masses is that it can has Dirac mass, Majorana mass or contribution from both. Unfortunately it is too complex to explain here.

One of the minimum requirements to send backwards-in-time messages with a particle that is 1/100000 faster than C in all reference frames is to have one of the detectors travelling at γ=1/(1-v²/c²)^1/2>100000 relative to us. The OPERA detector has a mass of 1.766 ktons. Getting something like that to such ultrarelativistic velocity may very well be out of reach of humanity for the remaining of Solar system life out of general physical principles. Do not count on it for the next 200 years.

Yeah, a couple of the neutrino eigenstates are actually imaginary, and would thus yield a ftl velocity. My favourite explanation so far (I expect experimental error, of course, but I can dream) is that the ftl effects observed are because of the short distances involved. Assuming the neutrinos can flip between eigenstates (I believe they can, but particle physics isn't my area of expertise), on a long trip the few ftl eigenstates are averaged out by all the sub-ftl ones, giving a mean speed less than c. By contrast, in the short flight from CERN to Grasso, the neutrinos in imaginary states stay so long enough to yield a predominantly ftl signal. That said... in hindsight that's probably unlikely; it would result in a stretching of the signal which, while maybe not evident in the old data, should definitely have been revealed in the latest batch of experiments.

Now remembering that gravity travels at the speed of light...

Lol wut?

The information from a gravitational event (in short, gravity waves) are believed to travel at c.

[Darvi]

IOW, if the sun suddenly collapsed into a black hole, it'd take a bit over 8 minutes until the Earth began plummeting into its doom.

[Osmosis Jones]

IOW, if the sun suddenly collapsed into a black hole, it'd take a bit over 8 minutes until the Earth began plummeting into its doom.

Nah, it would take a few billion years; the effective gravitational field from earth's perspective would be identical (ignoring all the traumatic gravity waves from the actual transformation of course). All the lights would go out at the 8 min mark though.

[MetalSlimeHunt]

IOW, if the sun suddenly collapsed into a black hole, it'd take a bit over 8 minutes until the Earth began plummeting into its doom.

Nah, it would take a few billion years; the effective gravitational field from earth's perspective would be identical (ignoring all the traumatic gravity waves from the actual transformation of course). All the lights would go out at the 8 min mark though.

And (they actually did a projection to see how long this would take if the Sun vanished) humans would go extinct in about a week as the whole planet freezes over. The last un-iced areas would be the centers of the oceans, which have enough stored heat to last about a month without outside input before falling to the freeze.

That would actually be a cool idea for a game: "The Last Week on Earth"

[Darvi]

And (they actually did a projection to see how long this would take if the Sun vanished) humans would go extinct in about a week as the whole planet freezes over. The last un-iced areas would be the centers of the oceans, which have enough stored heat to last about a month without outside input before falling to the freeze.

That would actually be a cool idea for a game: "The Last Week on Earth"

Fund it!

[Starver]

Quantum mechanics, because it's a matter of probabilities, however, would re-roll the dice (so to speak) each time you had an interaction, and so any given calculation would diverge from the previous barring a statistical fluke of astronomic proportions.

I must admit that I'm still of the opinion that below the available resolution of measurement (Planck-distance/time) there's a fully deterministic system that remains hidden to us but means that the seemingly strange dice-throws would always be those same seemingly strange dice-throws.  And to a GUT that is worthy of the title (and a probably impossible amount of information, of course) things like wave/particle dualities, slit experiments, quantum tunnelling, etc, etc are.

Of course, even if we knew what we needed to know, it'd be easier at low levels just to work on the probabilistic methods that we have (or shall continue to develop), entirely from QM, just as we deal with reletivistic.

I consider it a point of failure that I am so melded to the Deterministic/Hidden Variable view of the universe, for I know it might not be, but I just prefer a certain type of elegance in it.  And, so far, have not fully understood (or, rather, accepted) an apparent proof against this worldview that a certain experiment was supposed to have provided.


I also have this thing about looking for a PRNG that (in common with the Universe) is fully capable of giving the situation that a coin-toss comes up heads 100 times in a row, albeit so rarely...  of course, for this to be possible (and yet not certain) in the same ratio as Real Life, it needs to be a PRNG with an internal state having vastly more than 2¹⁰⁰ possible values through which to cycle in order to accommodate both this sequence and every other possible sequence of equal length at some point in its Pseudorandomness.  But that's more Information Theory than Physics, I put it here just as another example of my inane idealisms.