Posted: April 9, 2009 
Researchers use 3dimensional crystals to decode quantum information in black holes 
(Nanowerk News) Hirosi Ooguri and Masahito Yamazaki of the Institute for the Physics and Mathematics of the Universe (IPMU) developed a new method to use crystal melting models in three dimensions to identify quantum states of black holes in superstring theory. The result of this study will appear in the science journal Physical Review Letters.

In 1974, Stephen Hawking showed that black holes, though they are completely dark as classical solutions to the Einstein equation, emit heat and evaporate by quantum effects. If this phenomenon obeys the laws of statistical mechanics, there must be an enormous amount of quantum information stored in a black hole *).


The IPMU researchers have shown that each quantum state of a particular class of black holes in string theory corresponds onetoone to a molten crystal in three dimensions. For example, an ice is a crystal of water molecules. When it melts, it starts losing molecules from its corners. Similarly, the spacetime without a black hole is a perfect crystal. As the crystal loses molecules, the black hole grows larger. In the thermodynamic limit, where the size of individual atoms becomes negligible, they showed that smooth spacetime emerges and Hawking’s prediction is reproduced.

*) According to Hawking's computation, a black hole of M kg has exp(1016 M2) quantum states. For example, a typical astrophysical black hole formed by stellar collapse weighs about 1031 kg and carries as many as states.
