Second-order Cosmological Perturbations Engendered by Point-like Masses

Brilenkov, Ruslan; Eingorn, Maxim

doi:10.3847/1538-4357/aa81cd

Cited by 20 publications

(39 citation statements)

References 36 publications

(77 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…therein). Being based on our results, it is quite possible to construct similarly an appropriate second-order scheme for arbitrary scales (see [23] for the case of the standard ΛCDM components without supplementary fluids) and investigate the backreaction effects. This feasible scheme would be at an advantage over the second-order extension of the linear relativistic perturbation theory (see, e.g., [33] for the application of the latter to observable quantities), since all relevant small-scale effects would be properly taken into account.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Perfect fluids withω=constas sources of scalar cosmological perturbations

Eingorn

Brilenkov

2017

Physics of the Dark Universe

Self Cite

View full text Add to dashboard Cite

We make a generalization of a self-consistent first-order perturbation scheme, being suitable for all (sub-horizon and super-horizon) scales, which has been recently constructed for the concordance cosmological model and discrete presentation of matter sources, to the case of extended models with extra perfect fluids and continuous presentation. Namely, we derive a single equation determining the scalar perturbation and covering the whole space as well as define the corresponding universal Yukawa interaction range. We also demonstrate explicitly that the structure growth is suppressed at distances exceeding this fundamental range.

show abstract

Section: Resultsmentioning

confidence: 99%

“…In other words, we strive for finding such expressions for δε I , I = M, R, X, which would conform with the precision inherent in Eqs. (13)- (15) and have no second-order trace (see [12,23] for additional confirmative reasoning regarding the M-component). From (20) we get…”

Section: Cosmological Perturbation Theory Revisitedmentioning

confidence: 99%

Perfect fluids withω=constas sources of scalar cosmological perturbations

Eingorn

Brilenkov

2017

Physics of the Dark Universe

Self Cite

View full text Add to dashboard Cite

show abstract

“…where F , Z, A, G i are given by (53), (55), (57), and (61), all depending on the 59 initial values at τ 0 , and the 2nd metric perturbations in Poisson gauge are …”

Section: ⊥(2)mentioning

confidence: 99%

“…In ΛCDM framework, Ref. [53] calculated 2nd-order scalar and vector perturbations in the Poisson gauge.…”

Section: −16mentioning

confidence: 99%

Second-order cosmological perturbations. I. Produced by scalar-scalar coupling in synchronous gauge

Wang¹,

Zhang²

2017

Phys. Rev. D

View full text Add to dashboard Cite

We present a systematic study of the 2nd-order scalar, vector and tensor metric perturbations in the Einstein-de Sitter Universe in synchronous coordinates. For the scalar-scalar coupling between 1st-order perturbations, we decompose the 2nd-order perturbed Einstein equation into the respective field equations of 2nd-order scalar, vector, and tensor perturbations, and obtain their solutions with general initial conditions. In particular, the decaying modes of solution are included, the 2nd-order vector is generated even if the 1st-order vector is absent, and the solution of the 2nd-order tensor corrects that in literature. We perform general synchronous-to-synchronous gauge transformations up to 2nd-order generated by a 1st-order vector field ξ (1)µ and a 2nd-order ξ (2)µ . All the residual gauge modes of 2nd-order metric perturbations and density contrast are found, and their number is substantially reduced when the transformed 3-velocity of dust is set to zero. Moreover, we show that only ξ (2)µ is effective in carrying out 2nd order transformations that we consider, because ξ(1)µ has been used in obtaining the 1st-order perturbations. Holding the 1st-order perturbations fixed, the transformations by ξ (2)µ on the 2nd-order perturbations have the same structure as those by ξ(1)µ on the 1st-order perturbations.PACS numbers: 98.80.Hw, 04.25.Nx

show abstract

“…Meanwhile, the underlying physical reasons and resulting screening ranges are different in [6] and [7]. The scheme of [6] (see additionally [18,19]) is rooted in the so-called discrete cosmology studying how discrete gravitating masses interact in the expanding Universe. The finite interaction range arises in [6] and subsequent papers owing to the interpretation of the mass density fluctuation as the scalar perturbation source.…”

mentioning

confidence: 99%

Duel of cosmological screening lengths

Canay

Eingorn

2020

Physics of the Dark Universe

Self Cite

View full text Add to dashboard Cite

Two distinct perturbative approaches have been recently formulated within General Relativity, arguing for the screening of gravity in the ΛCDM Universe. In this paper we compare them and show that the offered screening concepts, each characterized by its own interaction range, can peacefully coexist. Accordingly, we advance a united scheme, determining the gravitational potential at all scales, including regions of nonlinear density contrasts, by means of a simple Helmholtz equation with the effective cosmological screening length. In addition, we claim that cosmic structures may not grow at distances above this Yukawa range and confront its current value with dimensions of the largest known objects in the Universe.As the science rapidly progresses, higher and higher accuracy of observations is achieved. For instance, such a future space mission as Euclid [3,4,5] is designed to probe the Universe expansion with unprecedented precision and impose new restrictions on dark energy, dark matter, and various cosmological parameters. In this connection, the legitimate demand for an advanced theory soars up too. In particular, it is quite natural to expect that Newtonian gravity is modified at large distances and ultimately reconciled with the standard relativistic perturbation theory. By dint of our narration, we aim at sparking interest in two distinct approaches [6,7] relying on General Relativity, which argue that gravity is actually screened, ceasing to be longrange far enough from its every single source. Hereinafter this Yukawa-type screening is sometimes called "cosmological" or "cosmic", since it originates from the presence of the cosmological background.Both cosmic screening approaches have been formulated in the framework of the standard ΛCDM (Λ cold dark matter) model, which is consistent with the observational data [8], though it is noteworthy that currently there is tension between the direct local measurement of the Hubble constant and the value of this very constant following from the Planck data on cosmic microwave background temperature and polarization (see, e.g., [9,10,11]). Furthermore, both original papers [6,7] focus on the matter-and Λ-dominated stages of the Universe evolution, so radiation and relativistic neutrinos are disregarded (though the results of [6] have been subsequently generalized to the case of additional perfect fluids with linear and nonlinear equations of state [12,13,14], as well as to the cases of nonzero spatial curvature [15], f (R) gravity [16] and the phantom braneworld model [17]).From the mathematical point of view, the cosmological Yukawa screening inevitably comes into play when the Einstein equation for the gravitational potential (scalar perturbation) is reduced to the Helmholtz equation, which replaces its popular rival of Poisson type. Meanwhile, the underlying physical reasons and resulting screening ranges are different in [6] and [7]. The scheme of [6] (see additionally [18,19]) is rooted in the so-called discrete cosmology studying how discrete gravitating mass...

show abstract

Second-order Cosmological Perturbations Engendered by Point-like Masses

Cited by 20 publications

References 36 publications

Perfect fluids withω=constas sources of scalar cosmological perturbations

Perfect fluids withω=constas sources of scalar cosmological perturbations

Second-order cosmological perturbations. I. Produced by scalar-scalar coupling in synchronous gauge

Duel of cosmological screening lengths

Contact Info

Product

Resources

About