구조 성장(RSD)

Realistic forecast: reconstructed Geff/G and fsigma8 for two modified-gravity scenarios (bump and dip). Both rule out GR at more than 2sigma around z approx 1. — Realistic forecast: reconstructed $G_\mathrm{eff}/G$ and $f\sigma_8$ for two modified-gravity scenarios (bump and dip). Both rule out GR at more than $2\sigma$ around $z \approx 1$ .

2023 · Phys. Rev. D 108 (2023) 023504

Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions. II. Modified gravity and massive neutrinos

Calderón, R., L'Huillier, B., Polarski, D., Shafieloo, A., Starobinsky, A. A.

We reconstruct the effective gravitational coupling $G_\mathrm{eff}(z)$ as a Gaussian process from forecast stage-IV growth data. DESI-like surveys could detect departures from General Relativity if dark energy is well determined; massive neutrinos do not change this, but assuming a ΛCDM expansion biases the inferred $\Omega_\mathrm{m}$ and $\sigma_8$ .

DOI · arXiv:2301.00640

수정 중력 구조 성장(RSD)가우시안 과정

Joint reconstructions of the effective gravitational coupling, H(z) and fsigma8(z) for three fiducial cosmologies; dashed lines show the truth. — Joint reconstructions of the effective gravitational coupling, $H(z)$ and $f\sigma_8(z)$ for three fiducial cosmologies; dashed lines show the truth.

2022 · Phys. Rev. D 106 (2022) 083513

Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions I: dark energy beyond $\Lambda$

Calderón, R., L'Huillier, B., Polarski, D., Shafieloo, A., Starobinsky, A. A.

Gaussian processes reconstruct the dark energy density from forecast stage-IV supernova, BAO and redshift-space-distortion data, assuming only a flat FLRW universe that becomes matter-dominated at high redshift, which also yields the growth history. Several dark energy models can be distinguished from ΛCDM at $2\sigma$ or more.

DOI · arXiv:2206.13820

암흑에너지 Ia형 초신성 중입자 음향 진동(BAO)구조 성장(RSD)가우시안 과정

Reconstructions of Omegade(z) (left) and the growth index gamma(z) (right) that fit the growth data better than ΛCDM, for three cases. — Reconstructions of $\Omega_\mathrm{de}(z)$ (left) and the growth index $\gamma(z)$ (right) that fit the growth data better than ΛCDM, for three cases.

2020 · MNRAS 494 (2020) 819

Defying the laws of Gravity I: model-independent reconstruction of the Universe expansion from growth data

L'Huillier, B., Shafieloo, A., Polarski, D., Starobinsky, A. A.

From redshift-space distortion data alone, we reconstruct the growth history with crossing statistics and Gaussian processes, derive the expansion history from it, and fit supernovae to constrain $\Omega_{\mathrm{m},0}$ and $\sigma_{8,0}$ . The results are consistent with flat ΛCDM and General Relativity.

DOI · arXiv:1906.05991

수정 중력 구조 성장(RSD)Ia형 초신성 가우시안 과정 제1저자

Theta(z) (top) and Ok(z) (bottom) from supernovae and BOSS/eBOSS BAO. A flat FLRW universe gives Theta = 1. — $\Theta(z)$ (top) and $\mathcal{O}_k(z)$ (bottom) from supernovae and BOSS/eBOSS BAO. A flat FLRW universe gives $\Theta = 1$ .

2018 · Phys. Rev. D 98 (2018) 083526

Falsifying ΛCDM: model-independent tests of the concordance model with eBOSS DR14Q and Pantheon

Shafieloo, A., L'Huillier, B.*, Starobinsky, A. A.

Combining model-independent expansion reconstructions from Pantheon supernovae and BAO, we test the FLRW metric and flatness, and use eBOSS DR14Q growth data to constrain $\Omega_\mathrm{m}$ , $\gamma$ and $\sigma_8$ . Everything is consistent with a flat FLRW universe, General Relativity and $\Lambda$ , with some tension at $z > 1$ .

DOI · arXiv:1804.04320

주요 논문 곡률과 FLRW 계량 수정 중력 Ia형 초신성 중입자 음향 진동(BAO)구조 성장(RSD)반복 평활법

Model-independent regions allowed by growth data (blue) compared with ΛCDM (red), at fixed gamma = 0.55 (left) and fixed sigma8 = 0.8 (right). — Model-independent regions allowed by growth data (blue) compared with ΛCDM (red), at fixed $\gamma = 0.55$ (left) and fixed $\sigma_8 = 0.8$ (right).

2018 · MNRAS 476 (2018) 3263

Model-independent cosmological constraints from growth and expansion

L'Huillier, B., Shafieloo, A., Kim, H.†

We reconstruct the expansion history from supernovae and fit growth-rate data to constrain $\Omega_\mathrm{m}$ , the growth index $\gamma$ and $\sigma_8$ without a dark energy model. The results agree with ΛCDM in General Relativity, and requiring a positive dark energy density tightens them further.

DOI · arXiv:1712.04865

주요 논문 수정 중력 Ia형 초신성 구조 성장(RSD)제1저자 지도 학생과 함께

논문

Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions. II. Modified gravity and massive neutrinos

Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions I: dark energy beyond Λ\LambdaΛ

Defying the laws of Gravity I: model-independent reconstruction of the Universe expansion from growth data

Falsifying ΛCDM: model-independent tests of the concordance model with eBOSS DR14Q and Pantheon

Model-independent cosmological constraints from growth and expansion

Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions I: dark energy beyond $\Lambda$