The Speed Of Light isn't the universal speed limit after all

[Smivs]

I'm not sure Walnuts can fall 50m sideways though. Do you have squirrels or similar?

[DaddyHoggy]

I'm not sure Walnuts can fall 50m sideways though. Do you have squirrels or similar?

I think it's no coincidence that Portal was also available for free download during the time of Eric's observations...

[Disembodied]

No fakedrives, just using gravity(which I believe is infinitely powerful) to pull the ship across the threshold of the speed of light. Are you saying that an object moving at the earth's escape velocity and moving towards it won't at any point have a velocity greater than the earth's escape velocity? My example was only to show that breaking the "light barrier" might be possible, if only for a brief moment. And if that's possible then a workaround could be found, eventually. Until we try, how can we know? Now, if only there were a way to break the "thought barrier" entrenched in nearly all learned men. I leave you with some words of wisdom from the master.

http://youtu.be/FDezrybpuO8

But there's no known way of inducing and projecting a gravity field unattached to a corresponding mass (let alone projecting one faster than light) – so a gravity sled which lets you travel FTL sounds pretty fake to me ...

An object moving towards the Earth at Earth escape velocity (25,000mph, give or take) will indeed experience acceleration under gravity and will end up moving faster than 25,000mph. But that's not the same thing at all as allowing acceleration past the speed of light. Photons (which by definition are moving at the speed of light) can and do fall into black holes (which have an escape velocity greater than the speed of light) – and yet those photons do not accelerate towards the black hole. They are already, effectively, moving infinitely fast.

Time slows down as acceleration increases: this has been demonstrated experimentally, and it matches Einstein's predictions. The faster you go, the less time you experience. Speed = distance/time. At the speed of light, there is no time: in other words, time = 0. Any number divided by 0 = infinity; therefore, over any distance you care to mention, if time = 0, then speed must = infinity. You can't go faster than infinity. It's a mathematical, even arithmetical, issue, not an engineering one. You can't engineer away a division by zero.

[DaddyHoggy]

It's even more mind-bendingly complicated than that.

Depending on your frame of reference, if you're on a 1km long spaceship that has a tunnel running up through the centre of it from nose to stern and you accelerate it up to 99.99% of the speed of light and then, stood at the back of the spaceship you shine a laser pointer down the tunnel towards the front of the ship, you, in the same frame of reference as the ship and the laser beam will "see" the laser beam arrive at the front of the spaceship in the "time" you'd expect (circa 1/300,000th of a second), but to the rest of the universe, you/the ship and the laser beam moving so slowly through time that the the laser beam still only travels at the speed of light and not c + 0.9999c

Having worked with some sub-atomic particles (sounds funny writing that, it's not like we went for a beer after work or anything) on ISIS that were near c and travelled far further in our frame of reference then they should have been able given how unstable they were because they were subject to a time dilation effect themselves.

[Disembodied]

It's even more mind-bendingly complicated than that.

I know, but I'm a medieval historian (worse, one who's recently back from the pub ...).

I can sort of wrap my head around time dilation ... it's the only way to keep S=D/T going where S is invariant, I suppose! There's a bit about it here which I think I might be understanding:
http://365daysofastronomy.org/2011/05/0 ... nd-slower/

Although that might be the unwarranted levels of self-confidence ... we'll see in the morning.

[Cody]

I know, but I'm a medieval historian (worse, one who's recently back from the pub... I can sort of wrap my head around time dilation

Semi-drunken medieval historians 1; Stone-cold sober contrabandistas 0;

Great thread!

[Eric Walch]

In all the comments about the phenomena, I only read about that they timed the starting-time, the end-time and distance. Nowhere I seem to read anything about correcting for the speed of the earth itself.

What if our galaxy speeds through the universe in a way that Palermo effectively moves to Geneve. That way you would expect that the particles arrive sooner.

And according to Astronews of 22 sept there are more reasons to doubt the current findings:

Neutrinos, however, there seem to care less and have an average of 60 billionths of a second before their destination. Although a rather simple measurement is concerned, outside of CERN physicists to keep in mind that their colleagues are the victims of a systematic measurement error. The weakest link is likely the generation of the neutrinos, for which a target-plate is shot with heavy particles (protons). This has some uncertainty in the timing of the neutrinos ejected. Ironically, this time is established using GPS measurements, a system that is accurate owes to the theory of relativity. We are now waiting for the results of similar measurements in the U.S. and Japan are held. Only when also showing that neutrinos move faster than light, scientists will really begin to doubt the theory of special relativity.

[m4r35n357]

The conclusion that the ability to move faster than light would bugger up causality, of course, isn't a guarantee that you can't go faster than light... straightforward acceleration seems to be out, given the whole mass-increase thing, but maybe there are ways around that ...

Since you mentioned straightforward acceleration, you might find this interesting . . .

http://math.ucr.edu/home/baez/physics/R ... ocket.html

The technological hurdles are still immense bordering on impossible, but it's better than "no way" I reckon.

[Thargoid]

"We don't allow faster than light particles in here, get out!" said the bartender.

A neutrino walks into a bar.

[Disembodied]

The technological hurdles are still immense bordering on impossible, but it's better than "no way" I reckon.

Ultimately though one major issue with FTL in "real space" – i.e. no wormholes or space warps – is that travel at lightspeed is instantaneous, from the traveller's frame of reference. As soon as you hit lightspeed, you get to wherever you want to go, whether that's Pluto, Alpha Centauri or the edge of the observable universe 14 billion light-years away, immediately. In the frame of reference of an observer on Earth, your journey is taking 5 hours, 4 years or 14 billion years, but as far as the ship's crew is concerned, it takes no time at all. So travelling in "real space" faster than light means reaching your destination sooner than instantaneously ... which is a bit of a logical conundrum to add onto the technological and technical hurdles (like the vast amounts of shielding required to protect the ship from the effects of ploughing through the interstellar medium at even fairly modest fractions of c).

[CommonSenseOTB]

"We don't allow faster than light particles in here, get out!" said the bartender.

A neutrino walks into a bar.

Hehe!

[m4r35n357]

Ultimately though one major issue with FTL in "real space" – i.e. no wormholes or space warps – is that travel at lightspeed is instantaneous, from the traveller's frame of reference. As soon as you hit lightspeed, you get to wherever you want to go, whether that's Pluto, Alpha Centauri or the edge of the observable universe 14 billion light-years away, immediately. In the frame of reference of an observer on Earth, your journey is taking 5 hours, 4 years or 14 billion years, but as far as the ship's crew is concerned, it takes no time at all. So travelling in "real space" faster than light means reaching your destination sooner than instantaneously ... which is a bit of a logical conundrum to add onto the technological and technical hurdles (like the vast amounts of shielding required to protect the ship from the effects of ploughing through the interstellar medium at even fairly modest fractions of c).

Well I think you understand that I believe that nothing with rest mass will EVER reach light speed, and I don't have the slightest problem with that
But some eternal optimists are clinging to the hope that some way will be found . . . it won't.
The relativistic rocket is a great way of understanding the fundamental limitations of space travel, like say Shannon's limit in communications.
Seriously folks, read the article, and discover how to get to Andromeda in less than 30 years WITHOUT breaking the "light barrier"!

[DaddyHoggy]

"We don't allow faster than light particles in here, get out!" said the bartender.

A neutrino walks into a bar.

Brilliant!

[Disembodied]

Well I think you understand that I believe that nothing with rest mass will EVER reach light speed, and I don't have the slightest problem with that
But some eternal optimists are clinging to the hope that some way will be found . . . it won't.
The relativistic rocket is a great way of understanding the fundamental limitations of space travel, like say Shannon's limit in communications.
Seriously folks, read the article, and discover how to get to Andromeda in less than 30 years WITHOUT breaking the "light barrier"!

It's an interesting article, definitely! There's a lot more of that kind of material on the Atomic Rockets webpage:
http://www.projectrho.com/rocket/

Everything from rockets to torchships to reactionless drives to FTL of various flavours. Really useful for writing SF if you want to try to create a world that – while not necessarily 100% "hard" – at least hangs together so that all you need from the readers is a willing suspension of disbelief.

To get to the other side.
Why did the neutrino cross the Alps?

[m4r35n357]

There's a lot more of that kind of material on the Atomic Rockets webpage:
http://www.projectrho.com/rocket/

To get to the other side.
Why did the neutrino cross the Alps?

Oh dear Thanks for the link though.