Is it true that electric signals can be transmitted at least four times faster than the speed of light??

Question

I read an article that said electric signals can be transmitted at least four times faster than the speed of light. In an experiment the peak of an electric wave could be transmitted at 4 billion km/h (if i m not mistaken) but Einstein's theory would be preserved because it says that "no information could travel faster than light" (???) I don't understand this! Isn't "information" that electric signal that goes faster than light??

One of this articles is here:
http://www.newscientist.com/article.ns?id=dn2796

Can anyone please make clear what that stuff about "information" is??

Answer 1

It is like your shadow on a wall that moves faster than yourself when you move in front of a candle in a dark room--simply because of distance projections.

The two different-frequency waves make a composite group that may have its peak envelope moving faster than either component wave. A part of this group of waves reflects back and forth at impedance continuity points of the two types of coax cables. Those two effects combine may make an image of a random composite group to have a peak that appears on the oscilloscope as moving faster than the speed of light. However, that peak's movement is but an image of the beating together of multiple forward and reflected energy packets and not an energy packet propagating by itself.

Answer 2

Quoting from the article you referenced -- "...While the peak moves faster than light speed, the total energy of the pulse does not..."
It's strength variations in the energy that contains any information. A crude analogy would be an AM (..amplitude modulated..) radio signal where the information like words and music is contained. The peak is more just a kind of reference point around which variations swing.

Another key quote from your referenced website -- "...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..."

Answer 3

This is about the difference between group velocity and phase velocity.

Imagine you take a wave of a particular freuqnecy. This will clearly travel with the normal - or phase velocity - what we usually understand as the speed of light.

Now to encode information onto the wave you make it wiggle up and down in amplitude or make small changes to its frequency. This imposes another waveform on top of the carrier - its how radio, tv, mobile phone, internet etc ALL work.

This wave travels at a different speed - called the group velocity. And this speed may be lower or in some cases higher than the phase velocity.

But now thinl about sending me a message. You turn your transmitter on and the message is modulating on the carrier at a group velocity faster than light. However, the carrier CANNOT reach me faster than the speed of light, because it travels at the phase velocity.

So no rules are broken.

Answer 4

No. Light is the fastest known thing in the universe. Electronic signals would travel similarly to that of soundwaves. Information is really just a bunch of 0 and 1's according to an electronic device. That gets transmitted as a tiny electronic pulse for each. Light goes a little over 1 billion km/h. Nothing known to mn can go faster.

Answer 5

gotta go with the first two answers....speed of light is max....if we ever can break einstein's theory, and develop "warp" drive....all bets are off...