Einstein's theory 'may be wrong'. Sweet

[marshal zhukov]

GREAT NEWS, everybody ( I think )

I read this article at BBC, and the article talks about a proposition made by Australian phisicists that the speed of light was faster 6 to 10 billion years ago.
The site below has the details of the phisicist's suggestion.
http://news.bbc.co.uk/2/hi/science/nature/2181455.stm
Quoted from the article.
"Australian physicists propose that it may have slowed over the course of billions of years.
The theoretical physicist believes the speed of light was faster six to 10 billion years ago than its current value - 300,000 km (186,300 miles) per second. "

I still don't understand his theory, but if his theory is correct traveling at the speed of light will never be possible.
This new suggestion offers a possibility of traveling even faster than the speed of light without having to slow time and all that.
At least that is what my understanding of the article.
All I know is that traveling faster than light is vital for the future space exploration.

Why can't the speed of light be passed ? Meaning why is it such a barrier ?

 

[Sh3kel]

Because travelling at the speed of light would compress you to death.

 

[Eli]

The theoretical physicist believes the speed of light was faster six to 10 billion years ago than its current value - 300,000 km (186,300 miles) per second

Nah... It's just a photonic quantum fluctuation in our main deflector array.

Oh wait, we're not in Star Trek.

 

[redtom]

Some nerd told me that Eistein Theory Of Relativity is wrong in another matter, tell me if i'm wrong but according to the theory:

as object travels at the speed of light it will need infinite power in order to contain the infinite energy it will need to infinite in size therefore everytime a light particle travels at the speed of light it would absorb the entire universe and then some. This is only a given if light particle has a mass at first. Its a piece of matter so it must have weight nomatter how infinitely small.

Another point, light does change speed in certain conditions, apparently some American scientist in (I think) Colorado Uni. slowed some light particles down to about 30 mph.

Also, I read somewhere that they managed to make a light particle travel back in time.

 

[Eli]

Originally posted by redtom

Another point, light does change speed in certain conditions, apparently some American scientist in (I think) Colorado Uni. slowed some light particles down to about 30 mph.

Light speed can definitely slow, it depends on the matter is passes through. But I think the article is saying that it's the light speed in vacuum that was faster than it is now.

 

[anarchywrksbest]

Of course light can slow down, like when it passes through water - refraction - rainbows and stuff.

And isn't right that you have to have a mass of absolute zero to travel at the speed of light?

 

[insurgent]

Originally posted by redtom
Another point, light does change speed in certain conditions, apparently some American scientist in (I think) Colorado Uni. slowed some light particles down to about 30 mph.

Hey, that was a Danish scientist in the US! I don't remember her name, but she was the first to ever slow light and she managed to get the speed down to 6 km/h IIRC...

 

[CivMonger]

there is a physics formula I learned in grade 11 physics, that I have now forgotten that states travelling at light speed is impossible. Something about the faster you go the heavier you get so the more fuel you need to propel you which makes you even heavier or something like that.

 

[IceBlaZe]

Well according to Einsteins relativity theory e=mc^2 right?.

That means, that Energy and Mass are actually the same thing in a different measure.
Just like, for example, Inch and Meter are the same thing only a different measure.

So, based on that theory, the coefficient of the formula is the speed of light square.

It is known therfor that the faster we go, the heavier (well, the mass increases but let's not aruge about tangentials) we get.

If a baseball player throws a ball at 100mph, the ball will get heavier, even if only a bit heavier.

The closer we get to the speed of light, the heavier we get, and the slower our perception of time is because even the neurons in our brain get heavier, etc.

Now, if a certain machine keeps accelerating the closer it's speed gets to the speed of light the much heavier it will get, the more energy it will need, etc etc.

It comes to a situation where you just keep getting heavier and heavier for every slight increase in speed and speed of light is unachievable or something.

I can explain it better and more precisely, but im too lazy.

 

[The Troquelet]

If I remember correctly, light NEVER slows down. Light isn't matter, it's energy. When we speak of light "particles", that would be "photons" which is just a convenient way of splitting up light which acts not only like a particle but also in some respects like a wave [like Xrays, which are the same thing as light only more compacted, both are "EMR" electromagnetic radiation, or radiant energy].

Matter, of course, also acts not only in particles, but can be said to act like a wave, according to Heisenberg I think. Of course, the waves of ordinary matter are so compact we can treat it like a particle, if I understand correctly.

Anyway, LIGHT NEVER SLOWS DOWN, refraction, the effect of water on light, is a DEFLECTION of light not a ******ATION of light, IIRC.

Also, FTL [fasterthanlight] particles have been discovered, they are called tycons, or typhons or something like that, they are tiny quark like particles, and apparently move at greater than light speeds while moving backwards relative to us in time [they go back in time]. Wierd.

 

[Akka]

I'll try to keep it as simple as possible. It will probably be somehow oversimplification, but well...

It's plain obvious that if you want to speed up, you need to use more energy. The faster you want to go, the more energy you need.
Reaching the light speed would require infinite energy. As nothing can produce "inifinite" energy, you can't go as fast as light.

 

[anarchywrksbest]

Not if you create a 'bubble' of subspace around FTL vessel. This will mean your ship is always in a place with different rules and so you won't be affected by the regular laws of phyics...... I either heard that on Star Trek or my physics teacher, probably Star Trek.....

 

[jpowers]

The Internet is slow enough already - do we really need light moving at 6 km/hr? Talk about a long time to download...

 

[Akka]

Originally posted by The Troquelet
If I remember correctly, light NEVER slows down. Light isn't matter, it's energy.

Energy and matter are the same thing under two different forms.

When we speak of light "particles", that would be "photons" which is just a convenient way of splitting up light which acts not only like a particle but also in some respects like a wave [like Xrays, which are the same thing as light only more compacted, both are "EMR" electromagnetic radiation, or radiant energy].

Matter, of course, also acts not only in particles, but can be said to act like a wave, according to Heisenberg I think. Of course, the waves of ordinary matter are so compact we can treat it like a particle, if I understand correctly.

Anyway, LIGHT NEVER SLOWS DOWN, refraction, the effect of water on light, is a DEFLECTION of light not a ******ATION of light, IIRC.

I'm sorry, but light CAN be slowed down. You just need the appropriate force applied on it. Gravitation can do it (see the black holes).

Also, FTL [fasterthanlight] particles have been discovered, they are called tycons, or typhons or something like that, they are tiny quark like particles, and apparently move at greater than light speeds while moving backwards relative to us in time [they go back in time]. Wierd.

"tachyon"
If I remember well, they were purely theorical "particles" that could have existed.
I don't know if they were proven right, wrong, or if the idea is still waiting a conclusion.

 

[Akka]

Originally posted by jpowers
The Internet is slow enough already - do we really need light moving at 6 km/hr? Talk about a long time to download...

Computer does not use light/photons, they use electricity/electrons

 

[JuicyCivNewbie]

Tachyons have not yet been discovered, and there is some debate about weather they can actually be detected at all, IIRC. Tachyons would need to have 'imaginary' mass, to travel FTL. Photons, and anything else with 0 mass, always travel at light speed in a vacuum. Heavier things can't ever reach light speed, although if they could, they would have to have infinite mass, and yet zero length for outside observers.

 

[insurgent]

Found at American Institute of Physics
LIGHT HAS BEEN SLOWED TO A SPEED OF 17 METERS/SECOND by passing it through a Bose- Einstein condensate (BEC) of sodium atoms at nK temperatures. In general light is slowed in certain materials, a property exploited in making optical lenses. As the index of refraction of these materials gets higher, however, absorption increasingly takes its toll on the light beam. In an experiment at the Rowland Institute of Science, (Lene Vestergaard Hau, hau@rowland.org), physicists have used a BEC as the optical medium, but with the following important modification. They contrived a system of laser beams whose pattern of interference created an effect called electromagnetically induced transparency, allowing light to propagate unabsorbed but at greatly reduced speeds, in this case a factor of twenty million compared to the speed of light in vacuum; greater light-speed slow downs are expected, to as low as cm/sec. The researchers also observed unprecedentedly large intensity-dependent light transmission. Such an extreme nonlinear effect can perhaps be used in a number of opto-electronic components (switches, memory, delay lines) and in converting light from one wavelength to another. (Hau et al., Nature, 18 February 1999.)

Lene Vestergaard Hau is a Dane, and a very Danish name! [dance]

So, light has been slowed...

 

[Pongui]

Maybe light isn't magically special, after all. What if Einstein had not used the speed of light as a constant, but chosen "speed of snails"? Could anything then travel faster than a snail?

 

[Akka]

Originally posted by Sean Lindstrom
Maybe light isn't magically special, after all. What if Einstein had not used the speed of light as a constant, but chosen "speed of snails"? Could anything then travel faster than a snail?

You fail to understand the concept. It's not that someone suddendly and arbitrarily chosen the speed of light to be absolute limite. It's just that light is massless (or at least has no measurable mass), hence it's able to reach a speed that nothing having a mass can equal.

 

[insurgent]

OK, if we consider what would happen if we travelled faster than the speed of light, what would happen (assuming it is possible, therefore purely hypothetical)?

If we travel faster than light, then we would be invisible, right? if not, then we would be seen after we had passed, right?

Would we be seeing into the future, if we had windows in whatever craft we were in? Would everything be black, since our speed simply would stop us from seeing anything?

Would time stand still, since time slows the faster we go? If we travelled faster than light, would we then also be travelling back in time?

What do you think?

(fascinating subject...)