The Cosmological Constant and the String Landscape

Abstract

Theories of the cosmological constant fall into two classes, those in which the vacuum energy is fixed by the fundamental theory and those in which it is adjustable in some way. For each class we discuss key challenges. The string theory landscape is an example of an adjustment mechanism. We discuss the status of this idea, and future directions.

35 pages, 2 figures. Rapporteur talk at the 23rd Solvay Conference in Physics, December, 2005. v2: Small changes. Author notes that this is not a review article but a discussion of a few specific issues

References in corpus (9)

• The Anthropic Landscape of String Theory
• Non-Local Modification of Gravity and the Cosmological Constant Problem
• Computational complexity of the landscape I
• Landskepticism: or Why Effective Potentials Don't Count String Models
• Anthropic Distribution for Cosmological Constant and Primordial Density Perturbations
• Some Thoughts on the Quantum Theory of Stable de Sitter Space
• Probabilities in the landscape
• AdS and dS Entropy from String Junctions
• Supersplit Supersymmetry

Cited by in corpus (26)

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• Dark Energy and Dark Gravity
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• Properties of the scale factor measure
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• Scaling Solutions to 6D Gauged Chiral Supergravity
• On the Conformal Field Theory Duals of type IIA AdS_4 Flux Compactifications
• Dark Energy from Brane-world Gravity
• The Landscape "avant la lettre"
• Holographic Cosmological Constant and Dark Energy
• Arrow of Time in String Theory
• The Cosmological Constant Problem and Inflation in the String Landscape
• A Curvature Principle for the interaction between universes
• Gauge sector statistics of intersecting D-brane models
• A Renormalization Group Approach to the Cosmological Constant Problem
• Experimental constraints on the free fall acceleration of antimatter
• Degravitation, Inflation and the Cosmological Constant as an Afterglow
• Vacuum driven accelerated expansion
• Self-accelerated brane Universe with warped extra dimension
• Unitarity at Infinity and Topological Holography
• Horizon Complementarity and Casimir Violations of the Null Energy Condition
• Orbifold Branes in the $M_D\times M_{d^{+}}\times M_{d^{-}}$ Compactification of type II string on $S^1/Z_2$ and their cosmological applications
• Precision Cosmology and the Landscape
• A note on vacuum energy from the de Sitter spectrum
• Universe Decay, Inflation and the Large Eigenvalue of the Cosmological Constant Seesaw