Jonathan Osterman was a nuclear physicist who developed his research in the area of \u200b\u200bthe intrinsic fields of the subject during the decade of the twentieth century 50. In an unfortunate accident, is trapped in the chamber in his laboratory and suffers the total removal of their own "intrinsic field" (sic), disintegrating completely. Officially given up for dead, miraculously manages to rebuild its atomic structure, under a new guise and endowed with amazing superpowers. Naked, excellently equipped and surrounded by a bluish glow, from then on be known around the world as Dr. Manhattan, a member of the Watchmen, the superhero stars of the graphic novel by Alan Moore and Updated by Dave Gibbons brought recently hand film Zack Snyder Watchmen ( Watchmen , 2009). James Kakalios Account in his book The Amazing Story of Quantum Mechanics the blue Dr. Manhattan did it occur to Dave Gibbons for simple disposal. Apparently, on one hand, the red color to the character made her seem to be surrounded by flames, while the green color it resembled too much the Hulk. On the other hand, the rest of the tonal range would seem that his skin was normal, when what was intended was the opposite, given the special circumstances of the ordeal experienced by Osterman. So, we decided to give bright blue tone we all know. And according to the same Kakalios, perhaps the choice was, at last, after all, the most appropriate. Why? Let's see.
Since early last century it was known that certain transparent media such as glass, water or some crystalline substances emitted a faint blue-white glow when placed in the vicinity of intense radioactive sources. Marie Curie It had come to report on the observation of the phenomenon in his famous bottles containing radium salts, shining in the darkness of his laboratory in Paris. Overshadowed by the intrinsic importance of the discoveries in the field of radioactivity at the time and because, in principle, attributed its origin to a kind of fluorescence , the previous phenomenon went unnoticed until 1929 when a Frenchman named L. Mallet discovered the effect is now known by the name of Cherenkov radiation. His name has passed into history because their work did not provide a theoretical explanation of the observations made.
basic investigations were conducted from 1934 to 1938 by the experimental physicist Pavel A. Cherenkov, while under the supervision of Professor Sergei I. Vavilov. In 1937, two theoretical physicists, both members of the Academy of Sciences of the USSR Ilya Frank and Igor Tamm provided the theoretical basis. Cherenkov both as to the latter two were awarded the Nobel prize in 1958 for their contributions.
What we know as Vavilov-Cherenkov radiation, or simply Cherenkov radiation, is an optical phenomenon similar to the famous boom produced by supersonic flying objects when they exceed the speed of sound. Also you can see a similar phenomenon when a ship moves rapidly through the water. If the boat is quiet and disturb the surface of the water (dropping a stone, for example) will observe a group of concentric circular waves (The center coincides with the point where we threw the stone) that are moving away gradually. In contrast, if the boat starts moving, the waves are no longer concentric with increasing speed, tend to concentrate near the point where the bow. Exceeding the speed with which the waves propagate in the water, they come to form two wave fronts (one on each side of the boat) that are seen to leave a trace in the form of V , in which the apex of the letter coincides with the bow. In the air there is a phenomenon quite similar, only in three dimensions, forming a conical surface whose axis coincides with the direction that moves the flying object.
The analog optical (electromagnetic) to the two previous effects (mechanical and acoustic) is known as Cherenkov effect and occurs when an electrically charged particle moving through a transparent medium with a speed exceeding the speed of light ( electromagnetic waves) in the same medium. And you must understand this as a violation of the precepts of Einstein's special relativity. Indeed, the speed that no material object (equipped with mass) can be overcome is that of light in a vacuum (299,792, 458 km / s). What happens is that light travels at different speeds in different media, always depending on the particular value of refractive index thereof. Thus, in the water, the speed of light is 33% slower than in vacuum because the refractive index is 1.33 instead of 1. Not surprisingly, then, to find certain radioactive substances capable of emitting electrons (beta radiation ) and that these relatively easily exceed the speed of light in the medium in which they are specific.
Suppose we have an electron (that is any electrically charged particle) in a straight line passing through a sheet of glass. In regions close to the passage of electron polarization occurs , ie the electron clouds of atoms in glass is offset from the positions previously occupied due to Coulomb repulsion caused by the electron travel, resulting in structures called dipoles. If the charged particle velocity does not exceed that of light in the glass, the dipole given sufficient time arranged symmetrically with respect to the instantaneous position of the electron. In this way, do not emit any radiation. However, if the speed exceeds the speed of light in the glass, the scenario is completely different. Now, the arrangement of the dipoles is asymmetric, because they have no time to follow the electron blooming. The dipoles begin to emit radiation all in a single angle with respect to the original direction of the particle that passes through the middle (hence, all emissions form a conical surface whose axis coincides with the direction of motion). The radiation from each dipole interfere constructively and produce a coherent light similar to that of a laser. This light is Cherenkov radiation, and in the case of water or glass, the emission cone angle is about 41 º. For air, only slightly more than 1 º.
The work of Frank and Tamm to suggest that the amount energy that accompanies the Cherenkov radiation varies inversely with the square of the wavelength of the same, ie focuses on blue-violet region of the visible spectrum. And this is the same bright blue tint seen in the water of the swimming pool of a nuclear reactor. Where else do you know? Exactly! In the skin of Dr. Manhattan. Do you produce then, somehow, the quirky doctor, electrically charged particles at high speed emitting Cherenkov radiation? So ask your artist, Dave Gibbons, who first chose the color of bloody chance, right? He'll know ...
Sources:
Cherenkov Radiation: its Origin, Properties and Applications . Jelley JV. The Physics Teacher. Vol I (5), 203-209. November 1963.
The Amazing Story of Quantum Mechanics . James Kakalios . Gotham Books. 2010.
My fucking brain, Sergio L. Palacios (Ph. D.), Journal of Mental intelects Tara and absolutely superior, Vol 69, p. 69-96. November 2010.
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