A clock field interacting with matter in a Riemannian 4D space creates emergent Lorentzian patches, replacing the Big Bang singularity with a smooth signature-flip boundary and allowing an almost de Sitter early phase.
Canonical reference
The Emergent Universe: inflationary cosmology with no singularity
Canonical reference. 100% of citing Pith papers cite this work as background.
abstract
Observations indicate that the universe is effectively flat, but they do not rule out a closed universe. The role of positive curvature is negligible at late times, but can be crucial in the early universe. In particular, positive curvature allows for cosmologies that originate as Einstein static universes, and then inflate and later reheat to a hot big bang era. These cosmologies have no singularity, no "beginning of time", and no horizon problem. If the initial radius is chosen to be above the Planck scale, then they also have no quantum gravity era, and are described by classical general relativity throughout their history.
citation-role summary
citation-polarity summary
roles
background 5polarities
background 5representative citing papers
Affine ANEC obstructs non-static flat and open FRW from being null geodesically complete while ANEC-satisfying, but allows explicit scalar-field realizations for closed FRW with NEC-respecting matter.
A no-go theorem proves flat and open FRW universes cannot be nonsingular, geodesically complete and ANEC-consistent while closed universes can, with positive curvature mimicking phantom dark energy at the 1% level.
Constructs an explicit closed FRW curvature-supported bounce-inflation model with a canonical scalar field that remains geodesically complete, NEC-compliant, and yields standard slow-roll predictions.
Improved GUP deformations applied to FLRW cosmology with Ashtekar-Barbero variables produce a non-singular emergent universe coasting from constant volume without a bounce and with a universal maximum energy density.
Phantom Chaplygin gas forces the Einstein-frame lapse to change sign smoothly while the causal-frame lapse stays positive, yielding a robust non-singular bounce even with extra matter.
Quantum deformation of projective phase-space geometry induces a conformally deformed FLRW metric whose time-dependent corrections modify inflationary background equations, slow-roll parameters, and perturbations in a covariant manner.
This review traces the history of dynamical dark energy, presents the no-go theorem against single-field crossing of w = -1, and surveys viable Quintom constructions including multi-field models and modified gravity in light of DESI DR2 hints.
A review arguing that current DESI/DES data favor Quintom-B dark energy, where the equation of state crosses w=-1 from below to above, with applications to bounces and CMB birefringence.
citing papers explorer
-
The emergent Big Bang scenario
A clock field interacting with matter in a Riemannian 4D space creates emergent Lorentzian patches, replacing the Big Bang singularity with a smooth signature-flip boundary and allowing an almost de Sitter early phase.
-
Affine ANEC selects the closed FRW branch for geodesically complete cosmology
Affine ANEC obstructs non-static flat and open FRW from being null geodesically complete while ANEC-satisfying, but allows explicit scalar-field realizations for closed FRW with NEC-respecting matter.
-
Open case for a closed universe
A no-go theorem proves flat and open FRW universes cannot be nonsingular, geodesically complete and ANEC-consistent while closed universes can, with positive curvature mimicking phantom dark energy at the 1% level.
-
Geodesically Complete Curvature-Bounce Inflation
Constructs an explicit closed FRW curvature-supported bounce-inflation model with a canonical scalar field that remains geodesically complete, NEC-compliant, and yields standard slow-roll predictions.
-
Effective Improved-GUP Cosmology: Emergent FLRW Universe without a Bounce
Improved GUP deformations applied to FLRW cosmology with Ashtekar-Barbero variables produce a non-singular emergent universe coasting from constant volume without a bounce and with a universal maximum energy density.
-
Geodesic completion of big bangs from emergent geometry
Phantom Chaplygin gas forces the Einstein-frame lapse to change sign smoothly while the causal-frame lapse stays positive, yielding a robust non-singular bounce even with extra matter.
-
Quantum-Deformed Phase-Space Geometry and Emergent Inflation in Effective Four-Dimensional Spacetime
Quantum deformation of projective phase-space geometry induces a conformally deformed FLRW metric whose time-dependent corrections modify inflationary background equations, slow-roll parameters, and perturbations in a covariant manner.
-
The Quintom theory of dark energy after DESI DR2
This review traces the history of dynamical dark energy, presents the no-go theorem against single-field crossing of w = -1, and surveys viable Quintom constructions including multi-field models and modified gravity in light of DESI DR2 hints.
-
A short review on Quintom dark energy theory
A review arguing that current DESI/DES data favor Quintom-B dark energy, where the equation of state crosses w=-1 from below to above, with applications to bounces and CMB birefringence.