You end up with what is called a 'Bose-Einstein Condensate'. This is what happens to ordinary matter. For objects such as black holes, absolute zero is not relevant because there is no way that the physics inside the black hole can make itself known to we outsiders. There is nothing that you can assign the concept of energy to. Temperature is just another name for the average random kinetic energy of a collection of matter. If you lower this kinetic energy by essentially slowing the particles of a system down, the system often collapses into a denser state if it is the thermal pressure of the system that is supporting it.
A star, supported by thermal pressure, will collapse to a white dwarf or a black hole if its 'temperature' were reduced. But exotic objects such as black holes are different. The surface area of the black hole, according to Stephen Hawking and others in the mid-1970's can be thought of as a measure of its entropy, however, unlike for other systems upon cooling, the entropy of a black hole can never be decreased because the mass inside a black hole can never be reduced. If absolute zero represents a state of zero entropy, then a black hole can never reach this state EXCEPT by evaporating. This evaporation process takes 10^50 years or more, and no one really knows if the end state is a naked singularity or simply a quantum worm hole.
J ILA physicists have achieved a temperature far lower than has ever been produced before and created an entirely new state of matter predicted decades ago by Albert Einstein and Indian physicist Satyendra Nath Bose. Cooling rubidium atoms to less than 170 billionths of a degree above absolute zero caused the individual atoms to condense into a "superatom" behaving as a single entity. JILA is jointly operated by NIST and the University of Colorado at Boulder.
Results of the experiment were published in the July 14 issue of Science. Before photographing the superatom with a laser system, the physicists cooled the atoms to 20 billionths of a degree above absolute zero, the lowest temperature ever achieved. (Absolute zero, -273.15 C, is the theoretical point at which all atomic motion stops.) In the three dimensional graphic view above, color represents density; red is the least dense, followed by yellow, green, blue and white. As the temperature within the JILA atomic trap dropped, the rubidium atoms condensed from their normal state in the graphic on the far left to the blue-white "superatom" on the far right. The "superatom" is about 20 microns in diameter, or about one-fifth the thickness of a sheet of paper.
The trick to creating the superatom was to get a high enough density of atoms at a cold enough temperature. The JILA apparatus includes six diode lasers that slow the room temperature atoms down and an unusual magnetic trap that kicks the hottest atoms out of the trap, while preventing the coldest atoms from leaving. The 2,000 rubidium atoms forming the condensate are in a strange condition, existing in a kind of smeared-out, overlapping stew. While many theories have been offered, most of the experimental properties of the condensate are still a big unknown. The JILA researchers hope that superatoms will provide physicists with a new way to study quantum effects on a large scale.
Copyright 1997 Dr. Sten Odenwald
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