We are surrounded by objects of familiar sizes; we know how large our body is; we are sure: one chair is comfortable for one person only. In the micro-quantum world, in the world of microscopic things, everything seems less prosaic: a chair, reduced by a couple of hundred billion times and having taken the size of an atom, will lose its clear boundaries, like any object so reduced. Moreover, all objects can fit in one space, while not interfering with each other. Why? In the quantum world, objects are waves that penetrate each other, so five people, ten, and twenty may well sit on one chair. Such waves are called coherent waves.
Coherence means interconnectedness, coherence (cohaerens - binding, in communication). Coherent waves, respectively, have the same frequencies, the same amplitudes, the same phase difference. Monochromatic waves, unlimited neither in time nor in space, correspond to these signs.
In order to feel the coherence of waves experimentally, things (objects) not only need to be reduced, but also very cooled, i.e. underestimate the chaotic motion of atoms. And the question here is not just about the “minus”, but about billionths of a degree Kelvin. The wave properties of the same chair should become noticeable at an unimaginably low temperature: - 45 K.
An interesting feature of waves is the ability to coherently fold, i.e. in an orderly and consistent manner. For example, coherent waves in time are music. Yes, yes, music! Each sound of a sounding melody, its duration, its frequency, its pitch - strict ordering and conformity. The weakening of coherence is perceived by us as a false sound, and the loss of coherence is perceived as noise. It is coherence that distinguishes music from incoherent and sometimes annoying sounds.
In the same way as objects of the quantum world, coherence gives new qualities that are so valuable for creating and obtaining completely new materials, sometimes radically changing existing technologies.
It is no coincidence that more than 40% of the Nobel Prizes in the last two decades are connected precisely with coherent phenomena: cold atoms, liquid helium, and superconductors.
Methods for obtaining coherent waves:
- instrumental acquisition (dividing one wave from the source into two);
- division of the front.
The decimeter-millimeter ranges of electromagnetic waves are used primarily in communications and electronics. But over the past 15-20 years, their use has increased in non-traditional areas, and mainly in biology and medicine. And shorter wavelength ranges were used even earlier, from the moment of discovery of the source of coherent oscillations.
Have you heard of physiotherapy? Yes, of course. This is the first area of use of coherent waves in medicine. Warming up the tissues allowed (and now allows) to accelerate reactions (both chemical and biochemical), which determined the physiotherapeutic effect. Waves are able to penetrate deep into the body, directly into those tissues into which they are directed.
And how valuable is the discovery of hyperthermia! Back in the sixties of the last century it was established: coherent waves are capable of destroying malignant tumors.
No one is surprised today by laser surgery, which uses the same coherent waves, but only in very narrow beams that can destroy both soft and bone tissues. Various lasers are applicable here, with different frequencies, depending on the nature of the operations and tissues. Almost "bloodless" operations, after which the patient recovers much faster.
An analysis of new directions in the application of wave coherence suggests that both medicine and biology will soon become the main areas of their application.