Speed of light broken with basic lab kit

NewScientist.com news service ^ | 10:03 16 September 02 | Charles Choi

[decimon]

Speed of light broken with basic lab kit

10:03 16 September 02

NewScientist.com news service

Electric signals can be transmitted at least four times faster than the speed of light using only basic equipment that would be found in virtually any college science department.

Scientists have sent light signals at faster-than-light speeds over the distances of a few metres for the last two decades - but only with the aid of complicated, expensive equipment. Now physicists at Middle Tennessee State University have broken that speed limit over distances of nearly 120 metres, using off-the-shelf equipment costing just $500.

Jeremy Munday and Bill Robertson made a 120-metre-long cable by alternating six- to eight-metre-long lengths of two different kinds of coaxial cable, each with a different electrical resistance. They hooked this hybrid cable up to two signal generators, one of which broadcast a fast wave, the other a slow one. The waves interfere with each other to produce electric pulses, which can be watched using an oscilloscope.

Any pulse, whether electrical, light or sound, can be imagined as a group of tiny intermingled waves. The energy of this "group pulse" rises and falls over space, with a peak in the middle. The different electrical resistances in the hybrid cable cause the waves in the pulse's rear to reflect off each other, accelerating the pulse's peak forward.

Four billion km/h

By using the oscilloscope to trace the pulse's strength and speed, the researchers confirmed they sent the signal's peak tunnelling through the cable at more than four billion kilometres per hour.

"It really is basement science," Robertson said. The apparatus is so simple that Robertson once assembled the setup from scratch in 40 minutes.

While the peak moves faster than light speed, the total energy of the pulse does not. This means Einstein's relativity is preserved, so do not expect super-fast starships or time machines anytime soon.

Signals also get weaker and more distorted the faster they go, so in theory no useful information can get transmitted at faster-than-light speeds, though Robertson hopes his students and others can now rigorously and cheaply test those ideas.

Physicist Alain Hache at the University of Moncton in Canada adds that it may be possible to use this reflection technique to boost electrical signal speeds in computers and telecommunications grids by more than 50 per cent.

Electrons usually travel at about two-thirds of light speed in wires, slowed down as they bump into atoms. Hache says it may be possible to send usable electrical signals to near light speed.

Charles Choi

[decimon]

You won't get there any faster but you can know you were there before you arrive. Or something like that.

[TomServo]

Posted Here.

[Illbay]

"Cap'n, she's doin' Warrrrp Six! I canna give ye any more'n that without losin' the SHIP!"

[decimon]

Searched on "speed", "light" and "Einstein." Didn't come up.

[MonroeDNA]

I bought Richard Fenyman's, "QED," but had to put it down after the first few chapters.

He was a brilliant man, but nothing he said convinced me that light is particles, not waves. He kept going back to the particle counter. But from what I understand, the particle counter can be explained by wave theory, too.

No PhD here, but did ace EE school, which is tougher than physics at the undergrad level. An early fundamental principle we learned is that waves broadcast their arrival, long before the peak energy arrives.

Starts as tiny ripples...just like any wave in the ocean. Then the ripples get bigger and bigger, and finally the big one comes...then more ripples, well after it.

The hard part is sensing the early ripples. Quantum Mechanics won't pick them up. But chasing and amplifying all those in the back, will send a massive signal upfront, amplifying the early ripples.

But hey, I'm just an ex-auto mechanic.

[Arkinsaw]

Did they use an east-west vortex or a north-south vortex? I'm also wondering if they got some of the moon crystals.

[LasVegasMac]

Searched on "speed", "light" and "Einstein." Didn't come up.

If you would have searched on, "arrive before you leave" - or - "got there before I left" you would have found it.

Amazing stuff.

LVM

[realpatriot71]

Amazing stuff.

You know I've often wondered about this. I'm no physicist, but have always been a bit of an armchair philosopher. I don't understand how you can "exist" in two places at once, at least not in a "finite," particle built universe. My position is that you only exist in one place at any given time, so I'm not sure you would see yourself leaving, as the time relative to you is your actual existance.

Am I making any sense or just babbling nonesense? :-)

[decimon]

If you would have searched on, "arrive before you leave" - or - "got there before I left" you would have found it.

Sounds like a Vegas thing. :-)

[decimon]

Did they use an east-west vortex or a north-south vortex? I'm also wondering if they got some of the moon crystals.

If a Moon Pie leaving Little Rock in an east-west vortex passes a Moon Pie...

[lelio]

I think this boils down to that you're passing a "signal" and not any data.
Say that you have a flashlight and shine it against a wall that's a long way away.
Put an object in front of the light so that it casts a shadow. Note: this shadow is magnified a lot since the light from the flashlight spreads out.
Now move around that object. The speed of the shadow moving will be amplified just because the shadow is bigger than the object.
Repeat with larger distances and quicker movements till the shadow moves faster than light.
I believe this is all okay as there isn't "data" in the shadow and a signal is just moving around.

[decimon]

But hey, I'm just an ex-auto mechanic.

Didn't Einstein say he'd have been a plumber if he had it to do over again?

[flying Elvis]

Heck, just post a news crew outside of Congress and you'll see Dems moving at the speed of light so they can pontificate on tv.

[mikegi]

This is bogus. It's just a particular resonance effect, not FTL. All of these FTL experiments are misinterpreted. The one last year used an amplifying medium for the em waves ("Gain-assisted superluminal light propagation") which greatly amplified the rising part of the pulse then saturated. The resulting output appeared similar to the input pulse.

When one of these experiments makes a random input move FTL, then you can get interested.

[TomServo]

Odd - I did a search on "'light" and it worked just fine.

[FreedomFarmer]

Speed of light broken...

It must be true. Yesterday's thread on this went over 100 posts.

[2Trievers]

FYI ... for BOTH threads. Lab kits? Hehe &;-)

[Parley Baer]

HMMMM. Let's see if I have this straight. They sent light faster then "the speed of light". Sounds like the "speed of light" done need some adjusten there. ;) Parley

[Arkinsaw]

Depends if you have a trans-rotational Royal Crown Cola at the other end.

[expatpat]

You're correct that all the behavior of light can be explained in terms of waves. However, for some effects, where it most behaves like a particle, the wave explanation is pretty tortuous.