Now the real photons can be created from the virtual ones by implementing scientific technology. So lets see what it is !
Scientists at Chalmers have succeeded in creating light from vacuum – observing an effect first predicted over 40 years ago. The experiment is based on one of the most counterintuitive, yet, one of the most important principles in quantum mechanics: that vacuum is by no means empty nothingness. In fact, the vacuum is full of various particles that are continuously fluctuating in and out of existence. They appear, exist for a brief moment and then disappear again. Since their existence is so fleeting, they are usually referred to as virtual particles. A perfect vacuum is impossible to achieve, at least in theory. As anyone with any interest in quantum physics would know, the vacuum is full of various particles that fluctuate in and out of existence. These "virtual" particles have been the focus of scientist, Christopher Wilson. Working with his team at Sweden's Chalmers University of Technology, Wilson has succeeded in producing real photons from these virtual photons. Which, in layman's terms, means that they have created measurable light from nothing.
Creating light from nothing is possible by the Casimir effect. The static Casimir effect can be demonstrated by placing two mirrors both parallel and close together. If the gap is smaller than the wavelength of the virtual particles you can expect to see the mirrors push together as the virtual particles are excluded. We know this to be true, and it has been seen before.The dynamic Casimir effect is trickier as it involves moving said mirrors through space at relativistic speeds. At slower speeds it is easy enough for the virtual particles to adapt and remain paired until they disappear. At high speeds, however, the pairs are separated and therefore do not entirely disappear, instead they become real photons and cause the mirror to shine a light..Since it’s not possible to get a mirror to move fast enough,for the scientists they developed another method for achieving the same effect. Instead of varying the physical distance to a mirror, they varied the electrical distance to an electrical short circuit that acts as a mirror for microwaves.The “mirror” consists of a quantum electronic component referred to as a SQUID (Superconducting quantum interference device), which is extremely sensitive to magnetic fields. By changing the direction of the magnetic field several billions of times a second the scientists were able to make the “mirror” vibrate at a speed of up to 25 percent of the speed of light.
The result was that photons appeared in pairs from the vacuum, which we were able to measure in the form of microwave radiation. The scientists were also able to establish that the radiation had precisely the same properties that quantum theory says it should have when photons appear in pairs in this way. The “mirror” transfers some of its kinetic energy to virtual photons, which helps them to materialise. According to quantum mechanics, there are many different types of virtual particles in vacuum, as mentioned earlier. Göran Johansson, Associate Professor of Theoretical Physics, the reason why photons appear in the experiment is that they lack mass. Relatively little energy is therefore required in order to excite them out of their virtual state. In principle, one could also create other particles from vacuum, such as electrons or protons, but that would require a lot more energy.The scientists find the photons that appear in pairs in the experiment interesting to study in closer detail. They can perhaps be of use in the research field of quantum information, which includes the development of quantum computers.
However, the main aim of the experiment is that it increases the understanding of basic physical concepts, such as vacuum fluctuations – the constant appearance and disappearance of virtual particles in vacuum. It is believed that vacuum fluctuations may have a connection with “dark energy” which drives the accelerated expansion of the universe. So lets wait and see what more this experiment can do!
[via:Physorg]
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