A one-parameter family of α-attractor potentials interpolates between exponential and polynomial attractor predictions, letting n_s scan the range preferred by CMB+DESI.
Polynomial $\alpha$-attractors
7 Pith papers cite this work. Polarity classification is still indexing.
abstract
Inflationary $\alpha$-attractor models can be naturally implemented in supergravity with hyperbolic geometry. They have stable predictions for observables, such as $n_s=1-{2/ N_e} $, assuming that the potential in terms of the original geometric variables, as well as its derivatives, are not singular at the boundary of the hyperbolic disk, or half-plane. In these models, the potential in the canonically normalized inflaton field $\varphi$ has a plateau, which is approached exponentially fast at large $\varphi$. We call them exponential $\alpha$-attractors. We present a closely related class of models, where the potential is not singular, but its derivative is singular at the boundary. The resulting inflaton potential is also a plateau potential, but it approaches the plateau polynomially. We call them polynomial $\alpha$-attractors. Predictions of these two families of attractors completely cover the sweet spot of the Planck/BICEP/Keck data. The exponential ones are on the left, the polynomial are on the right.
citation-role summary
citation-polarity summary
years
2026 7roles
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background 3representative citing papers
Inflaton-gluon coupling induces early QCD confinement to suppress axion isocurvature perturbations and enable axion dark matter production in alpha-attractor inflation models.
The paper introduces new exponential and polynomial supergravity ξ-attractor models in the Jordan frame with non-minimal coupling and shows that Palatini gravity with independent affine connection has no supergravity embedding.
New ξ-attractors with non-minimal coupling and non-canonical kinetics yield Einstein-frame exponential and polynomial potentials whose ns spans 1-2/N to 1-1/N and r can reach zero as ξ grows, fitting Planck, BICEP/Keck, ACT, SPT, and DESI data, plus a supergravity realization.
Polynomial α-attractor P-models of inflation accommodate Planck and Planck+ACT CMB data for ranges of reheating temperatures when decays and fragmentation are included.
Two minimal single-parameter extensions of the α-Starobinsky model shift ns into the 1σ ACT DR6 region while keeping r < 0.038 and yielding T_re ~ 10^9 GeV for N_k in [50,65].
Gravity-mediated production of scalar and vector dark radiation yields Planck 2018 constraints on reheating temperature T_RH and background equation of state w_Φ, with comparisons to right-handed neutrinos, ALPs, and a generic spin-2 mediator.
citing papers explorer
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Unification of polynomial and exponential cosmological attractors
A one-parameter family of α-attractor potentials interpolates between exponential and polynomial attractor predictions, letting n_s scan the range preferred by CMB+DESI.
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Phenomenology of Inflaton-Driven Early QCD Confinement and Solution to Axion Isocurvature Problem
Inflaton-gluon coupling induces early QCD confinement to suppress axion isocurvature perturbations and enable axion dark matter production in alpha-attractor inflation models.
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Jordan Frame in Supergravity and Cosmology
The paper introduces new exponential and polynomial supergravity ξ-attractor models in the Jordan frame with non-minimal coupling and shows that Palatini gravity with independent affine connection has no supergravity embedding.
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New Exponential and Polynomial $\xi$-attractors
New ξ-attractors with non-minimal coupling and non-canonical kinetics yield Einstein-frame exponential and polynomial potentials whose ns spans 1-2/N to 1-1/N and r can reach zero as ξ grows, fitting Planck, BICEP/Keck, ACT, SPT, and DESI data, plus a supergravity realization.
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Testing $\alpha$-attractor P-model of inflation by Cosmic Microwave Background radiation
Polynomial α-attractor P-models of inflation accommodate Planck and Planck+ACT CMB data for ranges of reheating temperatures when decays and fragmentation are included.
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Minimal Extensions of the $\alpha$-Starobinsky Model: Reconciling ACT DR6 and Reheating Constraints
Two minimal single-parameter extensions of the α-Starobinsky model shift ns into the 1σ ACT DR6 region while keeping r < 0.038 and yielding T_re ~ 10^9 GeV for N_k in [50,65].
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CMB signatures of gravity-mediated dark radiation in $\mathbf{\Delta N_{\rm eff}}$
Gravity-mediated production of scalar and vector dark radiation yields Planck 2018 constraints on reheating temperature T_RH and background equation of state w_Φ, with comparisons to right-handed neutrinos, ALPs, and a generic spin-2 mediator.