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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Integrable spin chain for the SL(2,R)/U(1) black hole sigma model
Yacine Ikhlef1, Jesper Lykke Jacobsen, Hubert Saleur
1Section Mathématiques, Université de Genève, Genève 4, Switzerland. yacine.ikhlef@unige.ch
Physical Review Letters
|April 3, 2012
Summary
Researchers developed a non-Hermitian spin chain, linking it to the SL(2,R)/U(1) black hole conformal field theory. This provides a physical measurement of the reflection amplitude, confirming theoretical predictions.
Area of Science:
- Quantum mechanics
- High-energy physics
- Conformal field theory
Background:
- Spin chains are fundamental in quantum mechanics.
- Non-Hermitian Hamiltonians are crucial for studying open quantum systems.
- Conformal field theories (CFTs) describe critical phenomena in physics.
Purpose of the Study:
- To introduce and analyze a novel spin chain model with a non-Hermitian Hamiltonian.
- To establish a connection between this spin chain and a specific CFT.
- To provide a physical interpretation and measurement of theoretical quantities.
Main Methods:
- Utilizing finite-dimensional spin-1/2 SU(2) representations.
- Employing analytical techniques to study the low-energy behavior of the spin chain.
- Comparing the calculated density of states with established theoretical formulas.
Main Results:
- The spin chain is described at low energies by the SL(2,R)/U(1) Euclidean black hole conformal field theory.
- The noncompact spectrum of the system was identified.
- The density of states was calculated and found to agree with predictions from Maldacena et al. and Hanany et al.
Conclusions:
- The study establishes a direct link between a non-Hermitian spin chain and a black hole CFT.
- This provides a concrete physical realization and measurement of theoretical concepts in quantum gravity and string theory.
- The findings validate existing theoretical frameworks and offer new avenues for research in these fields.
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