Small 7B reasoning models were fine-tuned on synthetic and curated QFT problems using RL and SFT, yielding performance gains, error analysis, and public release of data and traces.
Canonical reference
The Cosmological Constant Problem: Why it's hard to get Dark Energy from Micro-physics
Canonical reference. 80% of citing Pith papers cite this work as background.
abstract
These notes present a brief introduction to `naturalness' problems in cosmology, and to the Cosmological Constant Problem in particular. The main focus is the `old' cosmological constant problem, though the more recent variants are also briefly discussed. Several notions of naturalness are defined, including the closely related ideas of technical naturalness and `t Hooft naturalness, and it is shown why these naturally arise when cosmology is embedded within a framework --- effective field theories --- that efficiently captures what is consistent with what is known about the physics of smaller distances. Some care is taken to clarify conceptual issues, such as the relevance or not of quadratic divergences, about which some confusion has arisen over the years. A set of minimal criteria are formulated against which proposed solutions to the problem can be judged, and a brief overview made of the general limitations of most of the approaches. A somewhat more in-depth discussion is provided of what I view as the most promising approach. These notes are aimed at graduate students with a basic working knowledge of quantum field theory and cosmology, but with no detailed knowledge of particle physics.
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background 5representative citing papers
First-year DESI BAO data are consistent with flat LambdaCDM and, when combined with CMB, show a 2.5-3.9 sigma preference for evolving dark energy (w0 > -1, wa < 0) that strengthens with certain supernova datasets.
Stable flat solutions in scale-invariant scalar-tensor theories carry a non-vanishing cosmological constant unless the quartic coupling vanishes, and this vanishing is not radiatively protected, making a residual CC generic.
A lapse function in a 5D anisotropic gravity theory generates a global constraint that cancels Standard Model vacuum energy radiative corrections at all orders in the 4D effective theory.
Dynamical systems analysis of a Palatini k-essence model identifies fixed points for quasi-de-Sitter epochs, scaling solutions, and quintessence phases connected by heteroclinic orbits in flat FLRW cosmology.
Hybrid redshift model with postulated quantum correction fits Pantheon+SH0ES data to recover Planck-consistent expansion H_Λ and eliminates apparent drift in inferred Hubble parameter across bins.
QFT in FLRW spacetime yields a running vacuum energy density ρ_vac(H) that unifies mild dynamical dark energy today with H^4 inflation without an inflaton field.
String theory imposes constraints on dark energy but permits various construction attempts for de Sitter vacua and single-field exponential quintessence models despite obstructions.
citing papers explorer
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Fine-Tuning Small Reasoning Models for Quantum Field Theory
Small 7B reasoning models were fine-tuned on synthetic and curated QFT problems using RL and SFT, yielding performance gains, error analysis, and public release of data and traces.
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DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations
First-year DESI BAO data are consistent with flat LambdaCDM and, when combined with CMB, show a 2.5-3.9 sigma preference for evolving dark energy (w0 > -1, wa < 0) that strengthens with certain supernova datasets.
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The unavoidable de Sitter fate of a scale-invariant Universe
Stable flat solutions in scale-invariant scalar-tensor theories carry a non-vanishing cosmological constant unless the quartic coupling vanishes, and this vanishing is not radiatively protected, making a residual CC generic.
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A Lapse in the Cosmological Constant Problem
A lapse function in a 5D anisotropic gravity theory generates a global constraint that cancels Standard Model vacuum energy radiative corrections at all orders in the 4D effective theory.
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Dynamical system analysis of the cosmological phases in Palatini $k$-essence gravity
Dynamical systems analysis of a Palatini k-essence model identifies fixed points for quasi-de-Sitter epochs, scaling solutions, and quintessence phases connected by heteroclinic orbits in flat FLRW cosmology.
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Redshift Duality with Pantheon+SH0ES in a Planck-anchored Flat $\Lambda$CDM Framework: Implications for Hubble Tension and Observational Inference
Hybrid redshift model with postulated quantum correction fits Pantheon+SH0ES data to recover Planck-consistent expansion H_Λ and eliminates apparent drift in inferred Hubble parameter across bins.
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Running Vacuum in the expanding Universe: a unified QFT paradigm for Inflation and Dark Energy
QFT in FLRW spacetime yields a running vacuum energy density ρ_vac(H) that unifies mild dynamical dark energy today with H^4 inflation without an inflaton field.
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Dark energy from string theory: an introductory review
String theory imposes constraints on dark energy but permits various construction attempts for de Sitter vacua and single-field exponential quintessence models despite obstructions.