$\lambda \phi^4$ in dS

hep-th 2026-07 conditional novelty 8.0 of 10

The two-dimensional thermal Ising model on de Sitter provides exact cosmological correlators that stay finite at late times, with perturbative secular logarithms resummed into principal-series oscillations.

hep-th 2026-01 conditional novelty 8.0 of 10

The one-loop triangle in-in correlator of massless scalars in flat space is evaluated in closed form in terms of dilogarithms, with Landau analysis revealing its physical singularities and a partial-energy factorisati...

hep-th 2026-05 unverdicted novelty 7.0 of 10

Stochastic inflation is the leading infrared limit of a coarse-grained Schwinger–Keldysh effective theory, and the same Fokker–Planck dynamics follows from a Polchinski-type renormalization-group flow for the reduced ...

hep-th 2025-07 conditional novelty 7.0 of 10

The authors show that loop corrections do not alter tree-level time dependence in de Sitter correlators, so secular growth is a regularization artifact, not a physical effect.

hep-th 2025-07 conditional novelty 7.0 of 10

All-order necklace cosmological correlators are resummable only after a topology-dependent modification of analytic regularization, yielding a pole and a sign flip that are interpreted as non-perturbative large-N effects.

hep-th 2025-06 conditional novelty 7.0 of 10

At one loop and late time, the norm of the Hartle-Hawking no-boundary state vanishes as e^{S0}/(vol(SO(d,1)) S0^{d(d+1)/4}), and adding an observer stabilizes it to a large positive value.

hep-th 2025-05 conditional novelty 7.0 of 10

For holographic QFTs on constant-curvature manifolds, the spectrum is always discrete for negative curvature and always has a continuous component starting at m^2 = (9/4)α^{-2} for positive curvature.

hep-th 2024-12 conditional novelty 7.0 of 10

Matching in-in correlators between a full theory and its effective theory requires extra boundary terms in flat space, but those terms fade away in de Sitter space.

hep-th 2026-03 conditional novelty 6.0 of 10

SdSET is shown to renormalise and match like a flat-space EFT: tree-level trispectrum and six-point matching plus a one-loop power-spectrum match determine the SdSET couplings and initial-condition functions.

gr-qc 2025-12 conditional novelty 6.0 of 10

Relaxing the sharp cutoff or the Bunch-Davies initial state in stochastic inflation makes the noise colored, and relaxing the initial state also makes it non-Gaussian.

hep-th 2025-07 conditional novelty 6.0 of 10

Cosmological correlators in gravitationally constrained de Sitter states are conformally invariant and differ from QFT vacuum correlators, but relational observables with a heavy background state can reproduce QFT results.

hep-th 2025-07 conditional novelty 6.0 of 10

Stochastic inflation emerges from an open-quantum-system derivation, with a Lindblad master equation that reduces to and corrects Starobinsky's Fokker-Planck equation.

hep-th 2024-11 conditional novelty 6.0 of 10

The paper derives an inversion formula that defines de Sitter boundary operators as integrals of bulk fields against the bulk-to-boundary propagator, reproducing known two-point functions and perturbation theory.

hep-th 2024-11 conditional novelty 6.0 of 10

A new dimensional-regularization procedure extracts complete finite parts of inflationary loop integrals, yielding a regulator-independent one-loop tensor power spectrum in slow-roll inflation with no late-time divergence.

hep-th 2026-08 conditional novelty 5.0 of 10

Rare fluctuations in quantum walks are ruled by a measurement-induced relative entropy, and applying this to stochastic inflation yields a steady state that violates detailed balance.