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Entropy enhancement and black hole microstates
Iosif Bena1, Nikolay Bobev, Clément Ruef
1IPhT, CEA Saclay, 91191 Gif sur Yvette, France.
Physical Review Letters
|January 15, 2011
Summary
Entropy of fluctuating supertubes increases significantly in strong magnetic fields due to effective charges. This suggests smooth, horizonless configurations may explain black hole-like entropy.
Area of Science:
- String theory
- Quantum gravity
- Black hole physics
Background:
- Supertubes are fundamental objects in string theory.
- Microstate solutions describe black hole interiors.
- Entropy quantifies the number of possible states in a system.
Purpose of the Study:
- To investigate the entropy of fluctuating supertubes in specific microstate solutions.
- To explore the impact of magnetic fields on supertube entropy.
- To propose a mechanism for black hole entropy from smooth, horizonless geometries.
Main Methods:
- Analysis of fluctuating two-charge supertubes.
- Examination of three-charge scaling microstate solutions.
- Calculation of entropy dependence on effective charges in strong magnetic fields.
Main Results:
- Entropy is significantly enhanced by effective charges, exceeding naive expectations.
- Effective charges can be much larger than actual charges in strong magnetic fields.
- Fluctuating supertubes generate smooth geometries in certain duality frames.
Conclusions:
- An entropy enhancement mechanism is proposed.
- This mechanism may account for black hole-like entropy from smooth, horizonless configurations.
- This occurs in the parameter regime where classical black holes exist.
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