Researchers representing the University of Texas at Austin, found that to create a coating that make large objects invisible in many ranges, it is hypothetically possible, but the creators of such a device to deal with a number of fundamental limitations. In particular, the “invisibility cloak”, without an external power source is unlikely to protect large objects from the short electromagnetic waves, including visible light.
Engineers who published their work in the journal Optica, tried to figure out what should be a cloaking device, with which the object will be impossible to detect visible, infrared, radio and microwave ranges. As it turned out, accurately mask the object in some of these bands is theoretically quite possible, however, the larger will be the body, the more difficult it will become to hide it from the several kinds of radiation simultaneously. As the researchers explain, according to the received data, to mask a small antenna from radio waves hypothetically quite possible, while to make a man or, especially, the tank is transparent to visible light waves, which are much shorter, almost impossible.
Experts note that in this case we are talking about composite materials with no external power source. Therefore, when creating a better “invisibility cloak” in all likelihood, the more effective will be the use of active camouflage, the operation of which requires more energy. However, as emphasized by engineers, such technologies are today developed to a lesser extent, and even with their help to achieve invisibility in all ranges, without violating the laws of physics, it would be very difficult.
It is worth noting that to date, scientists from time to time declare the creation of working prototypes “of invisibility cloaks”, which, however, are still cloaked object only for radio waves, not in the visible range. For example, in March this year a group of engineers representing the University of science and technology Iowa state, presented a new flexible and easily stretchable material – meta-skin”.Related posts: