in spaaaaaace!! there's science

[Bit]

Something faster than light?
I know one who had the evil intention that this is possible...

[PaulH]

Neutrinos of a certain type may have just broken the light speed barrier.

[Bit]

Relative unfair

[cowsmanaut]

funny.. I've read several articles on this over the past week now and never thought about posting it here.. duh.. *smacks forehead*

[PaulH]

I've not read many, but am pretty sure there will be an error somewhere. Measuring to an accuracy of a few billionths of a second strikes me as near impossible anyway

[Jan]

So, old good Albert Einstein might have been wrong, after all. I knew there was something wrong with his theory - I've never understood it properly.

Funnily, the premises of our faculty are on Albertov street - named after A. Einstein, because he was teaching here (or in one of the next buildings, to be precise) in 1911-12. I guess they'll have to rename the street now. I'd suggest a more modern and accurate scholar, something like

Spoiler

Janov

street etc.

Anyway, we're very good at renaming streets, squares and whole towns here - some of the streets have changed their names more than 5 times during last 100 years as the regimes and rulers were changing (*) - so there would be no real problem with that.

(*) For instance, the current Vinohradská třída (an important boulevard in Prague) was called Jungmannova (-1920, Jungmann, a Czech literal scientist of German origin, *cough*), Fochova (1920-40, Foch, that French marshal), Schwerinova (1940-45, Schwerin, a German general), then Fochova again (1945-46, *cough*), Stalinova (1946-62, Stalin, that Russian mass-murderer of Georgian origin, *cough*) and now Vinohradská (1962-, vinohrady = vineyards, relatively unpolitical, but you never know here...).

Alright, so that was off-topic again, so where were we?

[cowsmanaut]

well, if you think about it the speed of light is the speed of photons.. why do they get to be the fastest in the universe why not Neutrinos? after all, they are supposed to be unhindered by the mass of other things.. photons can't say the same.

[Chaos-Shaman]

i've read that the human eye is capable of seeing one photon, i find it hard to believe though since it's so small and it moves so fast. i don't know how they measure something like that. my daughter brought this neutrino up at the dinner table last week, said everyone was a buzz in her school about it. guess FTL knew something we didn't at the time

[cowsmanaut]

well, does not the human eye see a photon when it's hit by it? ie, when you look at a red ball are you not being bombarded by photons within the red wavelength?

[Bit]

Yes, so it is. And I heard birds have four color 'channels' (different receptors) whereby we have just three, Wonder how they see the world - we probably can never imagine.
It's all just fascinating.

[oh_brother]

The barman says "I am sorry, we don't serve neutrinos". A neutrino walks into a bar. [/nerdy joke]

Anyway, yes we see the photons, but I have no idea how many we need before it registers. If we could detect one it would be very impressive.

I think I agree with PaulH though, if I had to bet I would say it is an error somewhere.

[cowsmanaut]

odd sciency aside comment: when I used to go camping with my folks, we had blow up matreses which were clear plastic, and in the dead of the dark night I would rub my hand quickly across the surface and you could see the tiny little sparks that looked almost greenish.. I used to try this at home, but there was too much ambient light to see effectively.. but in the dark dark night filled forrest within a lightless tent.. they were enough to light up the room.. So I guess what I'm trying to say is that it depends on how primed our eyes are to determine how much we would need to register the light..?

[PaulH]

Our eyes can register light if there is a pulse of about a dozen per 100ms.

Having looked at some of the data from the neutrino experiment, an error is almost undoubtedly going to be the reason. Either the time measured, or the distance measured.

[Rasmus]

@oh_brother: Hehe, really good joke, that one I will steal
@PaulH: I agree with you, I have really hard to imagine that one would find a particle that travel faster than light, even if I don't think it is imposible..

The reason why light is the fastest particle in the universe is because the photon is massless. All particles that doesn't have a mass are forced to always travel in the speed of light.. There are other particles that also is massless, but if i recall one of those are bound to a nucleus and the other one I can't remember..

Some things I checked out on the web:
The neutrino have accually been messured to travel faster than light at several locations, but it is with so small diffrence that the errormargin can explain it.. When the particles was messured from the supernova 1987A the photons accually reached the earth before the neutrinos did.. Meaning lightspeed > neutrinospeed!
I did also check out some texts about those 17-GeV och 28-GeV neutrinos that are messured to travel faster than light. There have accually been several experiments that have shown that this particles does travel faster than light.. But the thing is that those scientists that did those messurments does belive that it is the messuringtools that are responsible for the faster than light result, rather than the particles does travel FTL.
So my conclution is that one should wait to make those predictions until the scientists that discovered them says it is confirmed

But I am hoping that they accually is faster than light, then we would have a new paradigm shift

[Jan]

we would have a new paradigm shift

Nooooo! Imagine all the chaos in the heads of the students... and teachers! Why, on Earth, don't the scientists think about the impacts of their discoveries on children... and adults?

[PaulH]

Of course we have to ponder the impact if they have breached speed of light in a vacuum. But is this the ultimate speed in the universe? Is it the ultimate speed of light?

We know that light has a different v in different media ie refractive index. Neutrinos seem relatively unaffected by the medium which they are travelling through. Could it be that a vacuum is not quite empty, and is slowing light just a fraction, but not some neutrinos?

One reason could be the yet undiscovered, but theorised dark matter. If it is homogenously spread through the universe, then c will be measured the same everywhere, if affected of course. This brings up a surprising possibility: if the universe is expanding, then dark matter will become more rarified. Over time, the value of c may increase.

[PaulH]

Another, similar joke:

To get to the other side.

Why did the neutrino cross the road?

[Rasmus]

Hehe..
Well that sounds like a good reason why some neutrinos travel faster than light.. The photon has no mass but are charged, that is why it interacts with matter.. Neutrinos on the other hand are supposed to have a very small amount of mass but no charge, that is why it can travel right thru matter without any problem..
It sounds resonable that if vacuum not really is vaccum the light will be slowed down while neutrinos travel at the same speed.

So correct me if I am wrong.. Then neutrinos should then be able to travel faster than light in water for example. Sounds wrong, but is it?

[PaulH]

Neutrinos do indeed travel faster than light through water ie refractive index.

[Bit]

If a black hole even sucks light - shouldn't that accelerate when caught.
Forgive me - I like such questions
Got another one:
Regarding the wave character of light - if a photon goes the way of a wave - doesn't it has the longer way then and in fact a higher speed than measured for the whole beam?
(When we had experiments with light in school usually the room was dark - now guess... )

[Rasmus]

Neutrinos do indeed travel faster than light through water ie refractive index.

There we have it

if a black hole even sucks light - shouldn't that accelerate when caught.

Yes, the light does accelerate. But if we messure it we would still find that it has the speed of light. And that is only because the timeflow where the light is are slower in comperasment to us on earth. On the other hand if that light where to messure the lightspeed on earth it would be the other way around..
I guess we could think about it like this:
Light travels in m/s, if the meter increases the seconds have to increase with it so that m/s always is equals to the speed of light.. I guess my old physics teacher would kill me if he saw that sentence because that is really not how one calculates it, but I think it is a nice and simple way of thinking on it even if it is not entierly true..

Regarding the wave character of light - if a photon goes the way of a wave - doesn't it has the longer way then and in fact a higher speed than measured for the whole beam?
(When we had experiments with light in school usually the room was dark - now guess... )

The thing about light is that it can be both a particle and a wave at the same time, it all depends on what experiment is done with the light wave/particle.. Weird

(Once again, correct me if I am wrong.. I don't have a proper education in relativity or quantum physics, but I like reading about it)

[oh_brother]

This brings up a surprising possibility: if the universe is expanding, then dark matter will become more rarified. Over time, the value of c may increase.

Ooh, interesting! In that case what we call c is not really the true speed limit, it is a slightly reduced value due to interactions with dark matter. But that would mean that there still would be a "proper" value for c, we just have been underestimating it.

Then neutrinos should then be able to travel faster than light in water for example

The blue glow of nuclear reactors is caused by particles going faster than light in that medium, it is called the Cherenkov effect. But still they go slower than light in a vacuum.

[Bit]

When I retire (if that ever can happen), I'll study the mathematical side of quantums.
Like Einstein refused to accept some things of the quantum theory, I refuse to accept that the innerst things are complicated, There's something that maybe develop very fast to complicated terms, but I believe, the root of all is fascinating simple.

[PaulH]

Our theories tend to evolve - Newton's equations work well in almost all situations, but Einstein's realtivity addition is needed to expand on them.

Maybe we will expand on realtivity one day.

[Bit]

realtivity - nice one

[PaulH]

I typed too fast - must have got a neutrino in my 'a' key

[Bit]

If you read this: http://en.wikipedia.org/wiki/Quantum_entanglement
you really want to know what Einstein did smoke!

[Chaos-Shaman]

As far as we know, every time man creates a limit, man realises there is more. It is the choice of measurement. It's never going to be final. There is always something bigger or smaller, the infinity problem will always be there, so will the constant change of measurement be used which is why we question everything. Just because isn't good enough unless we're happy with the resulting answer. There is a dark speed as mentioned in another message as a joke. Maybe nobody but me agrees, but as long as the idea is there, it is theoretically possible. Call it antilight. It's how it is measured that is the question, someone imagined dark matter, and it's still not proven, life being so quantumized. If there was an absolute, then we'd be the ultimate, GOD.
If I imagine myself on the edge of the universe, then isn't my thought FTL. I'm back

[Bit]

Just saw TV-news:
reason for faster-than-light-particle was: a loose contact of a power plug of a measurement device.
pfft.

[Jan]

Have they tried turning it off and on again?