The Real No-Boundary Wave Function in Lorentzian Quantum Cosmology

Abstract

It is shown that the standard no-boundary wave function has a natural expression in terms of a Lorentzian path integral with its contour defined by Picard-Lefschetz theory. The wave function is real, satisfies the Wheeler-DeWitt equation and predicts an ensemble of asymptotically classical, inflationary universes with nearly-Gaussian fluctuations and with a smooth semiclassical origin.

1 + 10.5 + 2.5 pages, 2 figures. v2: minor changes and added references

References in corpus (20)

• Non-Gaussian features of primordial fluctuations in single field inflationary models
• Analytic Continuation Of Chern-Simons Theory
• Holography for Cosmology
• Lorentzian Quantum Cosmology
• The Classical Universes of the No-Boundary Quantum State
• The No-Boundary Measure of the Universe
• No smooth beginning for spacetime
• The Wave Function of Vasiliev's Universe - A Few Slices Thereof
• Holographic No-Boundary Measure
• Real-time Feynman path integral with Picard--Lefschetz theory and its applications to quantum tunneling
• The Origin of Time Asymmetry
• Probabilities in Quantum Cosmological Models: A Decoherent Histories Analysis Using a Complex Potential
• The Power of Perturbation Theory
• Quantum Probabilities for Inflation from Holography
• The No-Boundary Measure in the Regime of Eternal Inflation
• Quantum Transitions Between Classical Histories: Bouncing Cosmologies
• Quantum Transitions Through Cosmological Singularities
• Arrows of Time in the Bouncing Universes of the No-boundary Quantum State
• Holographic Tunneling Wave Function
• Hand-waving Refined Algebraic Quantization

Cited by in corpus (79)

• A Primer on Resurgent Transseries and Their Asymptotics
• No smooth beginning for spacetime
• Euclidean wormholes, baby universes, and their impact on particle physics and cosmology
• No Rescue for the No Boundary Proposal
• Tunneling wave function of the universe
• Review of the No-Boundary Wave Function
• Cauchy Slice Holography: A New AdS/CFT Dictionary
• The No-Boundary Proposal as a Path Integral with Robin Boundary Conditions
• Damped perturbations in the no-boundary state
• F-theory and Dark Energy
• Pixelated Dark Energy
• What is the No-Boundary Wave Function of the Universe?
• No-boundary prescriptions in Lorentzian quantum cosmology
• A Safe Beginning for the Universe?
• Tunneling wave function of the universe II: the backreaction problem
• Uses of Complex Metrics in Cosmology
• Loops rescue the no-boundary proposal
• Quantum Incompleteness of Inflation
• Cosmological consequences of a principle of finite amplitudes
• Pre-inflation and Trans-Planckian Censorship
• Observations in Quantum Cosmology
• The no-boundary proposal in biaxial Bianchi IX minisuperspace
• Lessons for quantum cosmology from anti-de Sitter black holes
• Lorentzian quantum cosmology goes simplicial
• Complex Saddles and Euclidean Wormholes in the Lorentzian Path Integral
• Complex, Lorentzian, and Euclidean simplicial quantum gravity: numerical methods and physical prospects
• Unstable no-boundary fluctuations from sums over regular metrics
• The Kontsevich-Segal Criterion in the No-Boundary State Constrains Inflation
• de Sitter at all loops: the story of the Schwinger model
• The no-boundary wave function for loop quantum cosmology
• The Universe as an Oscillator
• Spinor driven cosmic bounces and their cosmological perturbations
• The Wave Function of the Universe and CMB Fluctuations
• Loop quantum gravity, signature change, and the no-boundary proposal
• No-boundary Wave Function, Wheeler-DeWitt Equation and Path Integral Analysis of the Bouncing `Quantum' Cosmology
• Solving the flatness problem with an anisotropic instanton in Hořava-Lifshitz gravity
• Lorentzian path integral for quantum tunneling and WKB approximation for wave-function
• Vacuum decay in the Lorentzian path integral
• Constraints on non-minimal coupling from quantum cosmology
• A higher-dimensional view on quantum cosmology
• Suppression of spacetime singularities in quantum gravity
• No Smooth Spacetime in Lorentzian Quantum Cosmology and Trans-Planckian Physics
• Gravitational Decoupling and Picard-Lefschetz
• Gravitational waves in dark bubble cosmology
• De Sitter horizon entropy from a simplicial Lorentzian path integral
• Lorentzian quantum cosmology from effective spin foams
• Resurgence in Lorentzian quantum cosmology: No-boundary saddles and resummation of quantum gravity corrections around tunneling saddle points
• Configuration space for quantum gravity in a locally regularized path integral
• Wavefunction of the universe: Reparametrization invariance and field redefinitions of the minisuperspace path integral
• Probability distribution for the quantum universe
• Tunneling wavefunction proposal with loop quantum geometry effects
• Quantum cosmology of pure connection general relativity
• Complex degenerate metrics in general relativity: a covariant extension of the Moore-Penrose algorithm
• Unimodular Hartle-Hawking wave packets and their probability interpretation
• Cosmic eggs to relax the cosmological constant
• Hartle-Hawking No-boundary Proposal and Hořava-Lifshitz Gravity
• Truly Lorentzian quantum cosmology
• Simulating 0+1 Dimensional Quantum Gravity on Quantum Computers: Mini-Superspace Quantum Cosmology and the World Line Approach in Quantum Field Theory
• Path Integrals in Quadratic Gravity
• How to Create Universes with Internal Flux
• Initial wave-function of the universe is arbitrary
• Holographic (Eternal) Inflation
• Wavefunction for the Universe Circa the Beginning with Dynamically Determined Unique Initial Conditions
• Alternative route towards the change of metric signature
• Quantum cosmology of the flat universe via closed real-time path integral
• Jackiw-Teitelboim Gravity and Lorentzian Quantum Cosmology
• No smooth spacetime: Exploring primordial perturbations in Lorentzian quantum cosmology
• Remote Hawking-Moss instanton and the Lorentzian path integral
• Dissipative Emergence of Inflation from Quasi-Cyclic Universe
• Exact path integrals on half-line in quantum cosmology with a fluid clock and aspects of operator ordering ambiguity
• Summing over Non-singular Paths in Quantum Cosmology
• Measures of distance in quantum mechanics
• On the geometry of no-boundary instantons in loop quantum cosmology
• Gravitational thermodynamics without the conformal factor problem: Partition functions and Euclidean saddles from Lorentzian Path Integrals
• Wheeler-DeWitt Universe Wave Function in the presence of stiff matter
• Fuzzy instantons in landscape and swampland: review of the Hartle-Hawking wave function and several applications
• Wave function of the Universe as a sum over eventually inflating universes
• Tunneling in Quantum Cosmology and Holographic SYM theory
• Wave function of the universe in the presence of trans-Planckian censorship