Cosmic acceleration with a negative cosmological constant in higher dimensions

Kei-ichi Maeda; Nobuyoshi Ohta

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Cosmic acceleration with a negative cosmological constant in higher dimensions

Kei-ichi Maeda, Nobuyoshi Ohta

High Energy Physics - Theory · Submitted 2 Apr 2014

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim Namely de Sitter solution in the present system is stable if the cosmological constant is negative.

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What the abstract itself states, as probabilities: claims first 0.03 · states limitation 0.78 · human participants 0.01 · controlled comparison 0.02 · randomized assignment 0.01 · states quantitative result 0.09 · compares with prior results 0.09 · mentions code or data availability 0.01.

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arXiv listing abstract v2. Results and the main claim are underlined; show every role.

We study gravitational theories with a cosmological constant and the Gauss-Bonnet curvature squared term and analyze the possibility of de Sitter expanding spacetime with a constant internal space. We find that there are two branches of the de Sitter solutions: Both the curvature of the internal space and the cosmological constant are (1) positive and (2) negative. From the stability analysis, we show that the de Sitter solution of the case (1) is unstable, while that in the case (2) is stable. Namely de Sitter solution in the present system is stable if the cosmological constant is negative. We extend our analysis to the gravitational theories with higher-order Lovelock curvature terms. Although the existence and the stability of the de Sitter solutions are very complicated and highly depend on the coupling constants, there exist stable de Sitter solutions similar to the case (2). We also find de Sitter solutions with Hubble scale much smaller than the scale of a cosmological constant, which may explain a discrepancy between an inflation energy scale and the Planck scale.

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What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	We study gravitational theories with a cosmological constant and the Gauss-Bonnet curvature squared term and analyze the possibility of de Sitter expanding spacetime with a constant internal space.	contribution 0.98	0.91	0.04	asserted 0.42
s1	We find that there are two branches of the de Sitter solutions: Both the curvature of the internal space and the cosmological constant are (1) positive and (2) negative.	result 1.00	0.96	0.13	asserted 1.00
s2	From the stability analysis, we show that the de Sitter solution of the case (1) is unstable, while that in the case (2) is stable.	result 1.00	0.95	0.36	asserted 1.00
s3	Namely de Sitter solution in the present system is stable if the cosmological constant is negative.	result 0.94	0.94	0.76	asserted 1.00
s4	We extend our analysis to the gravitational theories with higher-order Lovelock curvature terms.	contribution 0.95	0.91	0.03	asserted 0.94
s5	Although the existence and the stability of the de Sitter solutions are very complicated and highly depend on the coupling constants, there exist stable de Sitter solutions similar to the case (2).	result 0.94	0.93	0.15	asserted 0.95
s6	We also find de Sitter solutions with Hubble scale much smaller than the scale of a cosmological constant, which may explain a discrepancy between an inflation energy scale and the Planck scale.	result 0.53	0.95	0.06	hedged possibility 0.84

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 1.00.

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The paper

Original abstract

We study gravitational theories with a cosmological constant and the Gauss-Bonnet curvature squared term and analyze the possibility of de Sitter expanding spacetime with a constant internal space. We find that there are two branches of the de Sitter solutions: Both the curvature of the internal space and the cosmological constant are (1) positive and (2) negative. From the stability analysis, we show that the de Sitter solution of the case (1) is unstable, while that in the case (2) is stable. Namely de Sitter solution in the present system is stable if the cosmological constant is negative. We extend our analysis to the gravitational theories with higher-order Lovelock curvature terms. Although the existence and the stability of the de Sitter solutions are very complicated and highly depend on the coupling constants, there exist stable de Sitter solutions similar to the case (2). We also find de Sitter solutions with Hubble scale much smaller than the scale of a cosmological constant, which may explain a discrepancy between an inflation energy scale and the Planck scale.

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References

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4 arXiv papers cite this in 4 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 3 sentences without a confident label

Cites it as background 1 paper

In this direction, a more natural way to achieve compactified extra dimensions is dynamical cementification (see Refs. [ref] involving different approaches and setups).

Growth of perturbations in higher dimensional Gauss-Bonnet FRW cosmology · Introduction · 0.80

What it cites · 14 sentences without a confident label

Compares with 1 paper

In another work [ref] , Wheeler-De Wit equation was studied semiclassically with a similar result.

Accelerated Expansion from Negative \Lambda · Introduction · 0.93

Cites as background 4 papers

One possibility is the brane inflation models [ref] , in which we assume test branes and do not take into account the back reactions.

Hierarchies from Fluxes in String Compactifications · Introduction · 0.82
One possibility is the brane inflation models [ref] , in which we assume test branes and do not take into account the back reactions.

Brane Inflation : String Theory viewed from the Cosmos · Introduction · 0.82
Earlier references on related subjects include [ref] – [ref] .

Realizing Scale-invariant Density Perturbations in Low-energy Effective String Theory · Introduction · 0.99

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