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Evolution Equation for Non-linear Cosmological Perturbations

Cosmology and Nongalactic Astrophysics · Submitted 23 May 2011

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

The authors' main claim Our approach can therefore reproduce the main features of the renormalized perturbation theory and (time)-renormalization group approaches to the study of non-linear cosmological perturbations.

how it is stated · hedged possibility 0.64 read the record →

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arXiv ID1105.4411 (version 1)
Pith IDWURDEIYP, Pith's permanent record of this paper and its review
CitationAntonio Riotto, Ram Brustein. "Evolution Equation for Non-linear Cosmological Perturbations." arXiv:1105.4411 (2011). https://pith.science/paper/WURDEIYP
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The paper's own sentences, arranged. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

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Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 5,605 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.21 · states limitation 0.40 · human participants 0.01 · controlled comparison 0.10 · randomized assignment 0.01 · states quantitative result 0.07 · compares with prior results 0.97 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; .

We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. Starting from the perturbed Einstein equations, we integrate out the non-relativistic degrees of freedom of the cosmic fluid and obtain a single closed equation for the gravitational potential. We then verify the validity of the new equation by comparing its approximate solutions to known results in the theory of non-linear cosmological perturbations. First, we show explicitly that the perturbative solution of our equation matches the standard perturbative solutions. Next, using the mean field approximation to the equation, we show that its solution reproduces in a simple way the exponential suppression of the non-linear propagator on small scales due to the velocity dispersion. Our approach can therefore reproduce the main features of the renormalized perturbation theory and (time)-renormalization group approaches to the study of non-linear cosmological perturbations. We conclude by a preliminary discussion of the nature of the full solutions of the equation and their significance.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#sentencerolethe authors' own workstates the main conclusionstrength
s0 We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. contribution 1.00 0.94 0.11 asserted 1.00
s1 Starting from the perturbed Einstein equations, we integrate out the non-relativistic degrees of freedom of the cosmic fluid and obtain a single closed equation for the gravitational potential. method 0.96 0.96 0.07 asserted 1.00
s2 We then verify the validity of the new equation by comparing its approximate solutions to known results in the theory of non-linear cosmological perturbations. method 0.82 0.95 0.08 asserted 0.98
s3 First, we show explicitly that the perturbative solution of our equation matches the standard perturbative solutions. result 0.76 0.94 0.07 asserted 1.00
s4 Next, using the mean field approximation to the equation, we show that its solution reproduces in a simple way the exponential suppression of the non-linear propagator on small scales due to the velocity dispersion. result 0.95 0.95 0.12 asserted 1.00
s5 Our approach can therefore reproduce the main features of the renormalized perturbation theory and (time)-renormalization group approaches to the study of non-linear cosmological perturbations. interpretation 0.85 0.80 0.47 hedged possibility 0.64
s6 We conclude by a preliminary discussion of the nature of the full solutions of the equation and their significance. future work 0.77 0.69 0.16 unclear 0.79

What kind of paper the classifier reports this is: method or tool 0.63 · evidence from proof or derivation 1.00.

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  • references and citing sentences
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Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

The paper
Original abstract

We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. Starting from the perturbed Einstein equations, we integrate out the non-relativistic degrees of freedom of the cosmic fluid and obtain a single closed equation for the gravitational potential. We then verify the validity of the new equation by comparing its approximate solutions to known results in the theory of non-linear cosmological perturbations. First, we show explicitly that the perturbative solution of our equation matches the standard perturbative solutions. Next, using the mean field approximation to the equation, we show that its solution reproduces in a simple way the exponential suppression of the non-linear propagator on small scales due to the velocity dispersion. Our approach can therefore reproduce the main features of the renormalized perturbation theory and (time)-renormalization group approaches to the study of non-linear cosmological perturbations. We conclude by a preliminary discussion of the nature of the full solutions of the equation and their significance.

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References
How the literature uses it

8 arXiv papers cite this in 9 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 · 5 sentences without a confident label

Uses its method or tool 1 paper
Compares with it 2 papers
Cites it as background 1 paper

What it cites · 2 sentences without a confident label

Compares with 1 paper
Cites as background 1 paper
  • With these assumptions, the relevant Einstein equations are (see, for instance, Ref. [ref] ) (00): 3^̋2+ 2∇^2 Ψ= ρ u_0^2 , (i0): ∇_i Ψ'+ ∇̋_iΨ= 1/2 ρ u_0 u_i , (ij): (2 Ψ”+6Ψ̋' -2 (^̋2-2 a”/a)Ψ+ (∇Ψ)^2-∇^2(Ψ-Φ))δ_ij +∇_i∇_j(Ψ-Φ)-2∇_iΨ∇_jΨ= ρ u_i u_j .

    Non-Gaussianity and the Cosmic Microwave Background Anisotropies · The non-perturbative equation for the gravitational potential · 0.87

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