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The one thing I agree with Einstein on:

Quick question:

What is meant by the use of the word "information" in the phrase "Information cannot travel faster than the speed of light"?

*Remembers bizarre Franko/wraith posts*
 
Yahweh said:
Quick question:

What is meant by the use of the word "information" in the phrase "Information cannot travel faster than the speed of light"?

*Remembers bizarre Franko/wraith posts*
Click to expand...


which states that no mass, pulse of information, or energy can travel faster than the speed of light. But nobody was really sure how this revised theory would affect the speed limit of a simple wave.

Wang had not claimed to have transmitted information faster than light. In fact, physicists had never clocked the maximum speed of an information-carrying beam of light.
Click to expand...

They are calling energy information in this instance?
 
Anything that can be detected could be information. Even if you took a four light-year long stick, and pointed it at alpha centauri, then twisted it, it would take four years for the other end to turn.

I never believed in time travel anyway. Time DILATION, however, has been proven. In other words, time seems to speed up and slow down, but moving through time? I don't think so.

Grandfather paradox. Anything that lets you do something impossible is impossible to make.
 
This is a case where the distinction between group velocity and phase velocity becomes important. The phase velocity is simply c/n, where n is the refractive index. If n is less than 1, which is possible, the phase of the pulse will propagate at faster than the speed of light.

Here's how I had it explained to me, and I'll try to rehash it here. A medium with n>1 disperses the multiple frequencies of the light as a fuction of their frequency. The lower the frequency, the greater the change, and conversely, for high frequency components the velocity doesn't change at all, or it is decreased. Now assuming you have a pulse or anything that can carry information, this would require a discontinuity in the electric field. The beginning of this discontinuity requires the superposition of an infinite number of high frequency modes, which as I stated above, travel at the speed of light or lower. The lower frequency modes are free to travel faster than the speed of light, but the part of the pulse that actually carries the information is the discontinuity.

Try thinking of it light this, you have a perfect triangular wave pulse (lets say it's equilateral). As the pulse propogates, the higher phase velocity of the lower frequency modes will distort the pulse, pushing the peak further forward, making it look more like a right triangle. However, it can't push past the discontinuity at the beginning, which travels at the speed of light, and actually carries the information.
 
Reminds me of a woo-woo study by some physics prof ( who musta had extremely safe tenure) about FTL information exchange a few years ago . It was on the order of cold fusion and warm superconductors.

The setup was a transfer of information, Beethoven as I remember, thru an IR emitter detector set and some weird microwave horn pair thingy. Both the outputs of the IR detector and the microwave device were fed to an oscilloscope and the weird horn thing's trace of the music preceded. proving FTL information exchange.

When ask about the mechanism that caused this behavior he sited the transitional state of the excited electron that shed energy and then reappeared at the lower energy state (orbit ) without a transitional journey, which is in the example the particular case. There are so many factors that affect most parts of this experiment that it appeared to me that it would be something one would find in the back pages of Popular Mechanics and not as a published report from a tenured prof funded by a major university but hey that's just me =)

There is however a macroscale device that does exhibit this behavior , when I saw the TV bit I immediately thought of it ..A Tunnel diode. The electrons appear on one side of the device disappear from one electrode only to reappear on the other side with no delay, there is no mechanical connection so the view is that they "tunnel" to the other side

The device works on the widely known "quantum-confinement effect " and is not fiction , but it just shows to go ya the false idea can be wrapped up just enough fact to make it appear to be plausible, like a pill to an unsuspecting dog wrapped in bacon.
The particulars are from memory so I'm sure I got details wrong , but the substance is solid.
 
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