中文
相关论文

相关论文: $Om$ Diagnostic for Dilaton Dark Energy

200 篇论文

As an update on the initial findings of DESI, the new results provide the first hint of potential deviations from a cosmological constant ($\omega=-1$), which, if confirmed with significance $>(2-4)\sigma$, would challenge the validity of…

宇宙学与河外天体物理 · 物理学 2025-12-18 Vipin kumar Sharma , Himanshu Chaudhary , Sanved Kolekar

This study investigates the cosmological implications of $f(R,\Sigma,T)$ gravity by reconstructing the Hubble parameter from a logarithmic parameterization of the $O_m(z)$ diagnostic. Our approach offers a model-independent way to probe the…

广义相对论与量子宇宙学 · 物理学 2026-05-12 N. Myrzakulov , Anirudh Pradhan , Anil Kumar Yadav , S. H. Shekh

A cosmological model with an energy transfer between dark matter (DM) and dark energy (DE) can give rise to comparable energy densities at the present epoch. The present work deals with the perturbation analysis, parameter estimation and…

宇宙学与河外天体物理 · 物理学 2021-07-02 Srijita Sinha

The equation of state (EOS) of the dark energy is the key parameter to study the nature of the dark energy from the observation. Though the dark energy is found to be well consistent with the cosmological constant with a constant EOS of…

宇宙学与河外天体物理 · 物理学 2015-09-24 Shi Qi

Gravitational waves from supermassive black hole binary mergers along with an electromagnetic counterpart have the potential to shed `light' on the nature of dark energy in the intermediate redshift regime. Accurate measurement of dark…

宇宙学与河外天体物理 · 物理学 2020-12-15 Pratyusava Baral , Soumendra Kishore Roy , Supratik Pal

We investigate the impact of non-linear corrections on dark energy parameter estimation from weak lensing probes. We find that using halofit expressions, suited to LCDM models, implies substantial discrepancies with respect to results…

宇宙学与河外天体物理 · 物理学 2011-03-18 Luciano Casarini , Giuseppe La Vacca , Luca Amendola , Silvio A. Bonometto , Andrea V. Macciò

Using a specific model for the expansion rate of the Universe as a function of scale factor, it is demonstrated that the equation of state of the dark energy cannot be determined uniquely from observations at redshifts $z\lesssim{\rm a…

天体物理学 · 物理学 2009-11-07 Ira Wasserman

We have run Monte Carlo simulations, for quasar clustering redshift distortions in the Two-Degree Field QSO Redshift Survey (2QZ), in order to elicit the power of redshift distortions (geometric Alcock-Paczynski and linear kinematic) to…

天体物理学 · 物理学 2007-05-23 M. O. Calvao , J. R. T de Mello Neto , I. Waga

Interacting dark energy models have been suggested as alternatives to the standard cosmological model, $\Lambda$CDM. We focus on a phenomenologically interesting class of dark scattering models that is characterised by pure momentum…

宇宙学与河外天体物理 · 物理学 2023-02-08 Maria Tsedrik , Chiara Moretti , Pedro Carrilho , Federico Rizzo , Alkistis Pourtsidou

Weak lensing convergence statistics is a powerful tool to probe dark energy. Dark energy plays an important role to the structure formation and the effects can be detected through the convergence power spectrum, bi-spectrum etc. One of the…

宇宙学与河外天体物理 · 物理学 2017-09-26 Bikash R. Dinda

We reconstruct dark energy properties from two complementary supernova datasets -- the newly released Gold+HST sample and SNLS. The results obtained are consistent with standard $\Lambda$CDM model within $2\sigma$ error bars although the…

天体物理学 · 物理学 2010-10-27 Ujjaini Alam , Varun Sahni , Alexei A. Starobinsky

A puzzling implication of current data interpreted in the $\Lambda$CDM cosmology is the preference for a negative sum of neutrino masses. Moving to $w_0w_a$CDM brings an appreciable fraction of the neutrino mass posterior back to positive…

宇宙学与河外天体物理 · 物理学 2026-03-17 Weiqiang Yang , Eleonora Di Valentino , Eric V. Linder , Sibo Zhang , Supriya Pan

We propose a dark matter model in which the signal in direct detection experiments arises from electromagnetic, not nuclear, energy deposition. This can provide a novel explanation for DAMA while avoiding many direct detection constraints.…

高能物理 - 唯象学 · 物理学 2011-01-14 Brian Feldstein , Peter W. Graham , Surjeet Rajendran

We present logistic dark energy model (LDEM), where the dark energy density follows a logistic function for the scale factor. The equation of state parameter of dark energy ($w_D$) transitioned from $-1$ in the distant past to its current…

宇宙学与河外天体物理 · 物理学 2024-06-27 Sarath Nelleri , Gopi Krishna , Navaneeth Poonthottathil

In this letter we argue that the CPL parameterisation for the dark energy equation of state is biased towards preferring such model over the constant $w$ while the latter bounds are still compatible with LCDM. For that we compare…

宇宙学与河外天体物理 · 物理学 2025-01-27 Ziad Sakr

We propose a novel dark-energy equation-of-state parametrization, with a single parameter $\eta$ that quantifies the deviation from $\Lambda$CDM cosmology. We first confront the scenario with various datasets, from Hubble function (OHD),…

广义相对论与量子宇宙学 · 物理学 2024-06-04 J. K. Singh , Preeti Singh , Emmanuel N. Saridakis , Shynaray Myrzakul , Harshna Balhara

Lyman-$\alpha$ forest data are known to be a good probe of the small scale matter power. In this paper, we explore the redshift evolution of the observable effective optical depth $\tau_{\rm eff} (z)$ from the Lyman-$\alpha$ data as a…

宇宙学与河外天体物理 · 物理学 2021-11-03 Anjan Kumar Sarkar , Kanhaiya L. Pandey , Shiv K. Sethi

DESI has reported a dynamical dark energy (DE) signal based on the $w_0 w_a$CDM model that is in conflict with Hubble tension. Recalling that the combination of DESI DR1 BAO and DR1 full-shape (FS) modeling are consistent with $\Lambda$CDM,…

宇宙学与河外天体物理 · 物理学 2026-03-20 Eoin Ó Colgáin , Saeed Pourojaghi , M. M. Sheikh-Jabbari , Lu Yin

In this paper, we study several models and parameterizations of dynamical dark energy (DE) that have been studied already in the past, in conjunction with the recently proposed model $w$XCDM, the running vacuum model (RVM) with and without…

宇宙学与河外天体物理 · 物理学 2026-03-03 Javier de Cruz Pérez , Adrià Gómez-Valent , Joan Solà Peracaula

We elaborate on a model of conformal dark energy (dynamical dark energy measured by the conformal age of the universe) recently proposed in [H. Wei and R.G. Cai, arXiv:0708.0884] where the present-day dark energy density was taken to be…

高能物理 - 理论 · 物理学 2008-11-26 Ishwaree P. Neupane