Cryogenics: Ultra-Low Temperature Physics; Implications
Because the universe is thought to have never been colder than the observed 2.7 K of the microwave background radiation—an idea based on modern cosmology—it is believed that Bose-Einstein condensates, along with other phenomena that occur below 2.7 K (superfluid helium, helium-3/helium-4 phase separation, adiabatic demagnetization of paramagnetic molecules, Fermi melting point of helium-3, Bose melting point of bosonic atomic gases, etc.) exist nowhere else in the universe other than in the laboratories here on Earth.
I argue that this may be a crucial error. For example, there has been observed at least one place in the universe that is colder than 2.7 K.
A brief history:
Important contributions to physics were introduced by Einstein in 1907 regarding the application of the quantum theory to the theory of specific heats, and concerning the quantum theory of gases in 1924-25 when he completed work on a new type of statistics known as Bose-Einstein statistics in which the existence of a new state of matter (a new category of statistics) was predicted called Bose-Einstein Condensates—a remarkable phenomenon discovered only in the last few years. The implications of these fundamental ideas have not yet been fully interpreted, evaluated, developed or theoretically submitted to application in the quest to illuminate the mysteries of the large and small-scale structures of the universe.
According to the fundamental laws of quantum mechanical processes that govern conditions in the micro-universe what we usually term a particle can sometimes behave as a wave. This is well known. Waves may likewise behave as particles. This may not be as well known. L. de Broglie (1924) hypothesized the existence of matter waves and expressed their wavelength in terms of the of momentum of the particles p: where h is Planck's constant. The more slowly the particle moves the less its momentum and the longer the de Broglie wavelength. According to the kinetic theory of gases low particle (or wave) velocities correspond to low temperatures. If a sufficiently dense gas of cold atoms can be produced, the matter wavelengths of the particles will be of the same order of magnitude as the distance that separates them. It is at this point that the diverse waves of matter can 'feel' one another and co-ordinate their state. This is called Bose-Einstein condensation. It is often said that a "superatom" arises since the whole composite arrangement is described by one single wave function exactly as in a single atom. We can also speak of coherent light in the case of a laser in the same way as of coherent matter.
An Indian physicist, Bose, (in 1924) made significant theoretical calculations concerning particles of light. He sent his findings to Einstein who broadened the theory to a particular type of atom. Einstein expected that if a gas of such atoms were cooled to an extremely low temperature all the atoms would abruptly congregate in the lowest possible energy state. The development is comparable to when drops of liquid form from a gas, therefore the term condensation—or like tiny droplets of water that form on a cold window when warm air comes into contact with it (but certainly not the same).
In 1995 the 2001 Nobel Laureates succeeded in attaining this extreme state of matter, Bose-Einstein condensate (BEC). Eric A. Cornell and Carl E. Wieman then produced a pure condensate of about 2000 rubidium atoms at 20 nK (nanokelvin), i.e., 0.00000002 degrees above absolute zero. Collective excitations and vortex formations have since been observed in condensates. Manifestations of Bose-Einstein condensation have previously been observed in more complex systems: condensation of paired electrons in superconductors (where loss of all electrical resistance occurs) and superfluidity or suprafluidity (loss of internal friction in fluids); both of which manifestations occur at very low temperatures.
BEC has also been attained in the most ubiquitous element in the universe:
Bose-Einstein Condensation of Atomic Hydrogen, Dale G. Fried, Thomas C. Killian, Lorenz Willmann, David Landhuis, Stephen C. Moss, Daniel Kleppner, and Thomas J. Greytak, Department of Physics and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (Received 11 September 1998).
But there is more. Due to Poincaré resonances, dynamical processes at higher temperatures also lead to long-range correlations, despite the short-range character of forces between particles—an essential fact that leads to asymmetry and permits evolutionary patterns in agreement with the thermodynamic description of nature.
The primary aim of this thread is to discuss the latest developments in the field of cryogenics (particulary below 2.7 K), in the hopes of gaining a better understanding of nature.
This frosty discourse should reveal certain alignments between the scientific stance and the artist who advocates non-objectivity: a common naturalism together with a common belief in the individual’s subjective capacity to transform appearances or concepts (particularly in cosmology). This dialogue, however, should also reveal a crucial difference. In one case, it is believed that after an intensely hot energetic phase of annihilation and separation a process began where undifferentiated matter gravitationally collapsed as the temperature of the universe drops during expansion. And the other, where that may not be the case.
“Mathematics, rightly viewed, posses not only truth, but supreme beauty; a beauty cold and austere, like that of sculpture”
(Bertrand Russell)
“Life always gets harder toward the summit - the cold increases, the responsibility increases”
(Friedrich Nietzsche)
CC
