Is still echoing in the air of the results of a recent survey, evil "translated" by the press in General as a "proof" of the impossibility of time travel.
To further confuse things, two independent groups of researchers have just demonstrate two different ways to make light pulses to travel at a speed higher than the 300,000 km/h set by Einstein's special theory of relativity.
Oddly enough, the conclusions of these new studies do not dispute that work of time travel and not tip the theory of relativity, but can have practical results, allowing real increases in the speed of information transmission by optical fibres.
Ways to see the light
Surpassing other jobs that have already demonstrated photons traveling faster than light and claimed particles, physicists now managed to make "a lot of light" seems to travel faster than would be allowed.
In the experiments, the light emerges from the other side even before you have entered material in front of that material.
All the confusion with these experiments emerges from the many ways in which the light can be "seen" and interpreted.
A pulse of light, for example, can be seen as a kind of electromagnetic radiation wave chispando by space. So, if you make a graph of the intensity of this pulse, it will start at zero, climbing gently to form a single peak, and then declining again to zero.
But one can also imagine that as a collection of waves with different wavelengths. What was once a single peak a single pulse of light, is the result of the sum of a series of waves oscillating up and down and overlapping on each other.
In the center of the wrist, the various waves align and reinforce each other, unlike the ascent and descent of the pulse, where the waves are out of sync and end up canceling.
The team from the universities of California (USA) and Imperial College London (Great Britain), author of the first study, adopted this point of view and built a hybrid material capable of reducing the speed of some wavelengths of light more than others.
This changed the way waves line up and shifted that peak-the point where the various waves reinforce doing peak jump ahead at a speed greater than the speed of light.
The material is a sandwich containing a copper perforated plate placed between two layers of Teflon 0.79 mm. These two layers keep the brightness and the direction of light waves, while the pattern of holes in the metal strengthens these waves.
The result was that the peak of the pulse of light emerged from the other side of the sandwich before entering the sandwich itself.
While the earlier experiments were less than 1% of pulses of light breaking the cosmic speed limit, the interaction between the metal and the teflon allowed up to 10% of the light to reach the other side 100 picoseconds before than they would if obeyed traffic rules cosmic.
Interpretation of relativity
But this doesn't violate the theory of relativity because this would require that the individual waves travel at a speed exceeding the exactly 299,792,458 meters per second.
Today, physicists interpret the relativity of a slightly more subtle: they consider that the theory of relativity States that the information cannot be transmitted faster than light.
And is the front of the first waves overlap-and not the exact position of the peak pulse of light-that determines the speed at which information can flow. This is why this experiment does not dispute the result of recent research which showed that the precursor of a photon optical does not exceed the speed of light.