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Related papers: Reconciling the local void with the CMB

200 papers

We use updated Type Ia Pantheon+ supernova, baryon acoustic oscillation, and Hubble parameter (now also accounting for correlations) data, as well as new reverberation-measured C IV quasar data, and quasar angular size, H II starburst…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-19 Shulei Cao , Bharat Ratra

The standard cosmological model, LCDM, provides an excellent fit to Cosmic Microwave Background (CMB) data. However, the model has well known problems. For example, the cosmological constant, is fine-tuned to 1 part in 10^100 and the cold…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 T. Shanks , R. W. F. Johnson , J. A. Schewtschenko , J. R. Whitbourn

We perform a cosmographic analysis using several cosmological observables such as the luminosity distance moduli, the volume distance, the angular diameter distance and the Hubble parameter. These quantities are determined using different…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jun-Qing Xia , Vincenzo Vitagliano , Stefano Liberati , Matteo Viel

We investigate early dark energy models in the context of the lensing anomaly by considering two different Cosmic Microwave Background (CMB) datasets: a complete Planck, and a second one primarily based on SPTPol and Planck temperature…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-20 Balakrishna S. Haridasu , Hasti Khoraminezhad , Matteo Viel

In a recent article, a simple `spherical bubble' toy model for a spatially varying vacuum energy density was introduced, and type Ia supernovae data was used to constrain it. Here we generalize the model to allow for the fact that we may…

Astrophysics · Physics 2009-11-06 P. P. Avelino , A. Canavezes , J. P. M. de Carvalho , C. J. A. P. Martins

The $\Lambda$CDM model is the current standard model in cosmology thanks to its ability to reproduce the observations. Its first observational evidence appeared from the type Ia supernovae (SNIa) Hubble diagram. However, there has been some…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-01 Isaac Tutusaus , Brahim Lamine , Alain Blanchard

Holographic dark energy (HDE) describes the vacuum energy in a cosmic IR region whose total energy saturates the limit of avoiding the collapse into a black hole. HDE predicts that the dark energy equation of the state transiting from…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Wei-Ming Dai , Yin-Zhe Ma , Hong-Jian He

Despite the many efforts, our theoretical understanding of the ultimate nature of the dark energy component of the universe still lags well behind the astounding experimental evidence achieved from the increasingly sophisticated…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Adria Gomez-Valent , Joan Sola , Spyros Basilakos

New Early Dark Energy (NEDE) is a component of vacuum energy at the electron volt scale, which decays in a first-order phase transition shortly before recombination [arXiv:1910.10739]. The NEDE component has the potential to resolve the…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-23 Florian Niedermann , Martin S. Sloth

Recently there have been suggestions that the Type Ia supernova data can be explained using only general relativity and cold dark matter with no dark energy. In "Swiss cheese" models of the Universe, the standard Friedmann-Robertson-Walker…

Astrophysics · Physics 2008-11-26 R. Ali Vanderveld , Eanna E. Flanagan , Ira Wasserman

The accelerated expansion of the Universe was proposed through the use of Type-Ia SNe as standard candles. The standardization depends on an empirical correlation between the stretch/color and peak luminosity of the light curves. The use of…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Rachid Ouyed , Nico Koning , Denis Leahy , Jan E. Staff , Daniel T. Cassidy

Recently there have been claims on model-independent evidence of dynamical dark energy. Herein we consider a fairly general class of cosmological models with a time-evolving cosmological term of the form $\Lambda(H)=C_0+C_H H^2+C_{\dot{H}}…

General Relativity and Quantum Cosmology · Physics 2015-10-08 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-27 Sarath Nelleri , Gopi Krishna , Navaneeth Poonthottathil

We present updated observational constraints on the spatially flat $\phi$CDM model, where dark energy is described by a minimally coupled scalar field $\phi$ with an inverse power-law potential $V=V_0 \phi^{-\alpha}$. Using Planck 2018 CMB…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Chan-Gyung Park , Bharat Ratra

Currently available Type Ia distant supernovae observed data seem to support evidence that the cosmic expansion of the universe is accelerating. This unexpected result is beyond any standard model of modern cosmology. The new concept…

Astrophysics · Physics 2008-03-21 D. C. Choudhury

We perform unbiased tests for the clumpiness of universe by confronting the Zel'dovich-Kantowski-Dyer-Roeder luminosity distance which describes the effect of local inhomogeneities on the propagation of light with the observational one…

General Relativity and Quantum Cosmology · Physics 2015-04-28 Zhengxiang Li , Xuheng Ding , Zong-Hong Zhu

How does a smooth cosmic distance ladder emerge from observations made from a single location in a lumpy Universe? Distances to Type Ia supernovae in the Hubble flow are anchored on local distance measurements to sources that are very…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-24 Obinna Umeh

The $\Lambda$CDM concordance cosmological model provides a remarkably successful description of the formation and evolution of structure in the Universe. However, a growing discrepancy between measurements of the expansion rate $H_0$ from…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-10 Isaque Dutra , Colin J. Burke , Priyamvada Natarajan , Weixiang Yu