Albert Polman and colleagues at the Institute of Atomic and Molecular Physics in Amsterdam, the Netherlands, did something that seems impossible.They created a device in which light behaves as if traveling at a speed no more and no less than infinite.Of course, as usual, they begin alerting you that your device does not contradict anything in Einstein’s theories – nor is the mechanism that lack that our spaceships traveling at warp speed .
But how to reconcile an “infinite speed” of light with the universal speed limit imposed by Einstein?Admittedly, it has been demonstrated that exceed the speed of light is mathematically possible , in addition to several experiments have “tricked” the physics to create superluminal pulses that travel faster than light.
But “infinite speed” of light is unheard of.
Refractive index = 0
In space, light travels at 299,792,458 meters per second. In other materials – in water or in glass, for example – it travels more slowly.The ratio between the speed of light in vacuum and the material in question defines the refractive index of the material, which is typically greater than 1.
However, scientists have discovered ways to manipulate the interactions between light and matter to create negative index of refraction – which is done using artificial materials known as metamaterials .Polman and colleagues created a kind of nanoscale tunnel where the index of refraction of light is zero – so the light waves of a specific wavelength move at infinite speed.
The device consists of a rectangular bar, measuring 2000 nanometers long and 85 nanometers thick, made of silicon dioxide – which is insulative – coated with silver.Technically this is a waveguide, a light guiding chamber.
Light with infinite speed
Light behaves differently within this waveguide because the electromagnetic fields must obey precise conditions at the ends of the device.The light with shorter wavelengths is reflected between the ends of the waveguide, and the peaks and valleys of the light that is going to overlap with the peaks and valleys of the light is coming, creating an interference band, a standard of light and dark like a barcode – brightness increases where the waves add up and disappears where the waves cancel each other out.
Above a certain wavelength “cutting” light does not spread further.And it is exactly that wavelength cutoff that things get interesting.Rather than producing an interference band – the alternation of light and dark – the entire wavelength glows.
This means that instead of behaving like waves with peaks equally spaced light waves behave as if their peaks were moving infinitely fast.
Thus, light oscillates in synchronization throughout the device, being literally along its entire length simultaneously.
Professor Nader Engheta, team member, explains that it does not violate relativity because the light has two speeds.A “phase velocity” describes how quickly the waves of a certain wavelength move, while the “group velocity” describes the rate at which carries the light energy – or information.
Only the group velocity must obey the universal speed limit, says Engheta, and it occurs inside the waveguide that he and his colleagues built.
The researcher adds that technology may have numerous uses, for example, as an antenna that emits light waves “formatted” with precision for use in optical logic circuits, ie processors based on light.The team also did not rule out the possibility of making a metamaterial of macroscopic dimensions with zero index of refraction.