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Loop Quantum Gravity and Recent Progress. Yi Ling ( 凌 意) ITP, Chinese Academy of Sciences Dec.27, 2003. Loop Quantum Gravity and Recent Progress. Brief history of loop quantum gravity Ashtekar-Sen variables Spin networks Applications and recent progress
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Loop Quantum Gravity and Recent Progress Yi Ling (凌 意) ITP, Chinese Academy of Sciences Dec.27, 2003
Loop Quantum Gravity and Recent Progress • Brief history of loop quantum gravity • Ashtekar-Sen variables • Spin networks • Applications and recent progress • Isolated horizon and entropy of black holes • Loop quantum cosmology • Positive cosmological constant and Chern-Simons states
Quantum mechanics +special relativity Quantum field theory Electromagnetic interaction (QED) Weak interaction Strong interaction (QCD) Renormalizable • Quantum field theory +general relativity Quantum gravity Gravitational interaction Non-renormalizable
Advices From Dirac • How then do they manage with these incorrect equation? These equations lead to infinities when one tries to solve them; These infinities ought not to be there. They remove them artificially… ------ The inadequacies of quantum filed theory.
General Relativity +Quantum Mechanics • 3+1 decomposition
General Relativity +Quantum Mechanics • Wheeler-Dewitt equation
Ashtekar-Sen Variables • Ashtekar-Sen variables a: SU(2) index
Constraints • 3+1 decomposition
SU(2) Diff(M) H ? Solutions to These Equations • Three steps
Loop States • Holonomy • Multi-loop states
Spin Networks • Spin networks j 1 j 2 v j 1 3
Discreteness of Quantum Geometry • Microscopic version of space
Discreteness of Quantum Geometry • Area spectrum j
Dynamics • Causal spin networks and spin foams t 3 t 2 t 1
Recent Progress in Loop Quantum Gravity • Isolated horizons and dynamical black holes • Quantum gravity with positive cosmological constant • The absence of singularity in loop quantum cosmology • Extending it to supergravity and M theory
Isolated Horizons and Statistical Entropy of Black Holes • Bekenstein-Hawking entropy
A Quick Review on Isolated Horizons • Motivations • Origin of black hole entropy • Physical laws of general black holes The zeroth and first law: Stationary black holes • (Quasi)local quantities on the horizon The mass, angular momentum and charges: Global concepts
A Quick Review on Isolated Horizons • Weakly isolated horizons • SO(3) (non-rotating) • Axi-symmetry(rotating) • Distortion • Dynamical horizons
Boundary Theory on Isolated Horizons • Self-dual action
Boundary Theory on Isolated Horizons • Consequences of boundary conditions on horizon
Boundary Theory on Isolated Horizons • Quantization
Boundary Theory on Isolated Horizons • From quantum general relativity • From quantum Chern-Simons theory
Boundary Theory on Isolated Horizons • Hilbert space
Boundary Theory on Isolated Horizons • Topological quantum field theory
Discrete Horizons From Quantum Geometry • The most probable distribution • The area of discrete horizon
Counting the Number of Microstates of Quantum Gravity • The entropy of discrete horizon
Fixing the Immirzi Parameter • Quasinormal modes of black holes • Bohr’s correspondence principle
Fixing the Immirzi Parameter • Quantum GR • Loop quantization of N=1 supergravity
Some Progress in Loop Quantum Cosmology • The absence of singularity in loop quantum cosmology Closed universe with k=1, Scale factor Originated from a big-bang
Some Progress in Loop Quantum Cosmology Quantum Mechanically We would expect Thus, is a classical relation.
Some Progress in Loop Quantum Cosmology Quantum geometry
Some Progress in Loop Quantum Cosmology • Positive cosmological and Chern-Simons states
Some Progress in Loop Quantum Cosmology • Kodama state • Problem of time • Energy-momentum relations(Lorentz Violation)
M theory Loop Quantum GR String theory D=11 Supergravity D=10 Supergravity D=4,N=1,2 Supergravity D=4,N=8 Supergravity Extend It to supergravity and M Theory