Scientists Mess with the Speed of Light (breaking the speed limit, sort of)

pure energy systems ^ | 19 aug 05 | Ker Than

[Brilliant]

The phase velocity is not the velocity of light. It's sort of like when you see those old movies of an automobile rolling down the street and it looks like the wheels are moving backwards. They aren't really of course.

[lepton]

Although information can be channeled through fiber optics at the speed of light, it can’t be processed at this speed because with current technologies, light signals must be transformed into much slower electrical signals before they are useful.

Much slower electrical signals? Hardly. The problem with electrical signals is not their speed, but the capacitance slowing down clear transitions, and the resistance at high frequency.

[AntiGuv]

This certainly doesn't amount to much of it's own accord, but I find it quite intriguing how researchers have been nudging at the edges of the theory of relativity. What it all means ultimately, I wouldn't dare venture to guess (oh, alright, I'm unconvinced that the speed of light is an unbreakable barrier - I am convinced that it certainly appears to be so in our current understanding - my contraryness is probably just wishful thinking). As for a ping list, I think it's great that you keep it from spinning out of control; your judgment is good enough for me!

[Izzy Dunne]

a popular misconception is that, according to Einstein’s special theory of relativity, nothing in the universe can travel faster than this speed.

Somebody 'splain to me where this 'misconception' is, because I was pretty sure that one of Einstein's laws is exactly that.

[Izzy Dunne]

186,000 miles per second.
It's not just a good idea. It's the law.

Actually, you can go up to 186,282 MPH without getting a ticket.

[Prime Choice]

Actually, you can go up to 186,282 MPH without getting a ticket.

Only because the radar guns max out at 185,500. Nyack!

[Reaganghost]

That's alright; some of us won't read it until yesterday.

[PatrickHenry]

As for a ping list, I think it's great that you keep it from spinning out of control; your judgment is good enough for me!

I probably take my ping list "responsibilities" too seriously. But I'd rather not have people dropping out because they get bothered by too many pings to trivial stuff. No one ever drops out because of too few pings.

[PatrickHenry]

Somebody 'splain to me where this 'misconception' is [according to Einstein’s special theory of relativity, nothing in the universe can travel faster than this speed], because I was pretty sure that one of Einstein's laws is exactly that.

I'm not sure what Arkie2 had in mind, but the inflationary big bang model has the universe briefly expanding FTL. I've seen various explanations as to why this doesn't create a problem, but it's probably because it doesn't involve any possible causality contradictions. Undoubtedly, an expert will pop in to show where I've botched this up. If so, I welcome the information.

[AntiGuv]

Exactly. I've dropped ping lists before because the flood of pings is just too overwhelming.

[leftcoaster]

Actually, you can go up to 186,282 MPH without getting a ticket.

That would be MPS. (And you wanted to be MY latex physicist...)

[Fester Chugabrew]

I probably take my ping list "responsibilities" too seriously . . .

You have a ping list?

[Izzy Dunne]

Uhh, well my statement is still true ;->
Of course you could also go faster, as in 186282 MPS.

[Arkie2]

If you'll look at the title of the article the note in parenthesis is mine. I'm aware nothing mentioned here violates Einstein's theories but it's intweresting from a technical viewpoint.

Actually, the most amusing aspect of this article is the note that scientists have slowed light to zero. If only it were true we would never have to worry about Hillary being elected prez!

[NY.SS-Bar9]

It's not just a good idea. It's the law.

That's what the said about the sound barrier.

[frgoff]

The velocity they are talking about isn't anything real. It's the speed at which the interference patterns between the different light frequencies pass.

Think of it this way: Say you have two fans spinning at different speeds and you put one in front of the other in front of a light source. As the fans spin, you'll see a shifting pattern of light and dark as the fan blades interfere with each other in transmitting the background light. The speed at which these patterns change can be much faster than the spinning speed of the fans, but it's not a real velocity.

Likewise, when you put multiple frequencies of light together, you get a similar effect. Bands of interference will move in the same direction as the light, but can move much faster than the light itself.

Unfortunately, the moment you try to analyze the information carried by the interference patterns, you are once again restricted to the speed of light because you have to wait for a certain number of patterns to pass by, and amazingly, that number is just enough to slow the whole thing back down to the speed of light again.

[frgoff]

The misconception is not being able to travel faster than light.

Actually, the relativity equations say no such thing. What they say is that you can't travel AT the speed of light, unless you are massless.

Once you get past the speed of light, the equations work again, except that a number of them have an imaginary component (sqrt-1).

A superluminary universe has some interesting properties according to relativity theory. Rest mass is at 2sqrt(2)c, doppler shifts are reversed, it takes infinite energy to slow DOWN to the speed of light, etc.

[Prime Choice]

That's what the said about the sound barrier.

The sound barrier didn't require near-zero mass to break.

[BootsOnTheGround]

"Actually, you can go up to 186,282 MPH without getting a ticket."

But it is one massive ticket.

[IronJack]

A superluminary universe has some interesting properties according to relativity theory. Rest mass is at 2sqrt(2)c, doppler shifts are reversed, it takes infinite energy to slow DOWN to the speed of light, etc.

Yeah, that makes sense. It's like approaching a limit from the "other side."