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[Another]

No one serious was aiming at a rewrite. Principles and equations that work would continue to work regardless of this, just in a slightly more bounded region. But the tsunami wall of theoretical publications on why FTL neutrinos may be possible is quite noticeable. A simple sum of all proposed mechanisms would probably produce speed of 3 c.

[MaximumZero]

Extending this logic, a spacecraft going "faster than light" would be subjected to such high time-dilation in that it subjectively would arrive at the destination before it embarked.

Worse than that.  It's not negative time that will pass, but imaginary time.  Which is different.  And almost certainly no less weird.

Isn't all time imaginary?

[Loud Whispers]

Extending this logic, a spacecraft going "faster than light" would be subjected to such high time-dilation in that it subjectively would arrive at the destination before it embarked.

Worse than that.  It's not negative time that will pass, but imaginary time.  Which is different.  And almost certainly no less weird.

Isn't all time imaginary?

Nope, it's just relative.

[Another]

Time an distances are usually considered real values and it is the metric signature that has different signs for time and space to produce Minkowski 4-space in special or general relativity.

[Kogut]

Extending this logic, a spacecraft going "faster than light" would be subjected to such high time-dilation in that it subjectively would arrive at the destination before it embarked.

Worse than that.  It's not negative time that will pass, but imaginary time.  Which is different.  And almost certainly no less weird.

Isn't all time imaginary?

Well, 5 (and any other real number) is also imaginary number.

[Nadaka]

In other CERN news:

http://science.slashdot.org/story/12/02/22/2116251/faulty-cable-to-blame-for-superluminal-neutrino-results

And...

http://science.slashdot.org/story/12/02/25/0410256/a-small-glimmer-of-hope-for-faster-than-light-neutrinos

[Karnewarrior]

A question I've always had about FTL travel is: How will you see? Imagine how it would look if you were moving faster than the light around you; You'd only be able to see the light that impacted your eyes, which means only certain directions would be visible to you. Turn towards the back of the ship and you're blind, turn towards the front and you're bombarded by particles moving way, way faster and with more energy than they're supposed to, relative to you.

Bay12, how would you fix this?

[Knight of Fools]

Sunglasses.

[Loud Whispers]

Bay12, how would you fix this?

Light would appear to warp around you, so I'd read a book.

[Starver]

Well, 5 (and any other real number) is also imaginary number.

No.

But it is complex, just with a zero factor in the imaginary direction.  Is that what you're thinking of?

[Starver]

A question I've always had about FTL travel is: How will you see? Imagine how it would look if you were moving faster than the light around you; You'd only be able to see the light that impacted your eyes, which means only certain directions would be visible to you. Turn towards the back of the ship and you're blind, turn towards the front and you're bombarded by particles moving way, way faster and with more energy than they're supposed to, relative to you.

Bay12, how would you fix this?

Any practical method of FTL travel across normal space would (should? could?) require that the traveller be wrapped in what, for want of any better way of putting it, is like the Star Trek 'warp bubble'.  Normality of space acts within that (or at least approaching its inner edges, thereof).

Whether or not that space-warping mechanism also intrinsically deals with incoming particles, such that particles ploughed into get 'shifted' into a kind of 'normality' so that you can see forward (a method for which a Handwavium shielding system would doubtless be required, in the first place), there is if course still the problem of not being able to have any input to the rear.  Except, of course, for the particles that are heading in your direction (emanated from objects now behind you) that you overtake.  Which your Handwavium conversion shields might well allow to enter the centre of your normality bubble from the rear, as if being a 'proper' rear view.

One reason why I think FTL travel is more elegant not through moving warp bubbles at FTL speeds (not counting numerous relativity effects) but instead via 'short-cut links' of some kind.  Capital-'D' "Doors" in space that lead directly to other Doors.  No problem with travel, it's wormholes (X-treme!) or similar, all the way.

Noting that elegance is no guarantee of likelihood.  I know that, but it's a good start until shown otherwise.

[Another]

I would be quite satisfied with just any form of FTL communication as currently even that does not appear to be ever possible.

Even if we will have those FTL neutrinos in the end there will likely still be no even a theoretical way to transmit information at FTL with them.

Suppose you have something net-charged inside your warped-space bubble. It will still have non-zero EM field outside of it and the bubble as a whole will emit Cherenkov radiation and lose momentum and energy until it stops being superluminal, right? Unless it's total mass is negative or zero, in which case it would uncontrollably gain more [negative]energy. I think that could mean something about a possibility to wrap any charged particles into something like an Alcubierre drive.

If there for some reason was a short-cut in space-time - I bet it would locally warp the metric so much that it would be no weaker disturbance than a black hole of a comparable size. Not likely travellable trough or even send-some-particles-trough.

[Reelya]

Extending this logic, a spacecraft going "faster than light" would be subjected to such high time-dilation in that it subjectively would arrive at the destination before it embarked.

Worse than that.  It's not negative time that will pass, but imaginary time.  Which is different.  And almost certainly no less weird.

Isn't all time imaginary?

Well, 5 (and any other real number) is also imaginary number.

Only if you take a very vague English language use of "imaginary", rather than the precise mathematical definition.

Consider numbers with the form :

a + bi

Where i = square root of -1

Numbers are called "imaginary" when b is not = 0

That's because you can conceive of 5 apples, even -5 apples (a debt in apples), or 1.5 apples (1 and half apples).

You cannot conceive of an amount of apples "five times square root of negative 1".

[Putnam]

You mean when b=/=0, right? >_>

[Reelya]

Sorry was typo which i already corrected.