Related papers: The failure of testing for cosmic opacity via the …
The cosmic distance-duality relation (CDDR), $d_L(z) (1 + z)^{2}/d_{A}(z) = \eta$, where $\eta = 1$ and $d_L(z)$ and $d_A(z)$ are, respectively, the luminosity and the angular diameter distances, holds as long as the number of photons is…
We compare distance measurements obtained from two distance indicators, Super- novae observations (standard candles) and Baryon acoustic oscillation data (standard rulers). The Union2 sample of supernovae with BAO data from SDSS, 6dFGS and…
In this paper, we present a cosmological model-independent test for the cosmic opacity at high redshifts ($z\sim5$). We achieve this with the opacity-dependent luminosity distances derived from nonlinear relation between X-ray and UV…
We investigate whether a violation of the distance duality relation (DDR), $D_L(z) = (1+z)^2 D_A(z)$, connecting the angular diameter and luminosity distances, can explain the Hubble tension and alter the evidence for dynamical dark energy…
The luminosity-angular distance relation for an expanding universe is given by $D_L=D_A(1+z)^2$. This relation is commonly proven by geometrical considerations from the source point of view assuming an expanding universe. In this note, the…
We test the distance--duality relation $\eta \equiv d_L / [ (1 + z)^2 d_A ] = 1$ between cosmological luminosity distance ($d_L$) from the JLA SNe Ia compilation (arXiv:1401.4064) and angular-diameter distance ($d_A$) based on Baryon…
Many new strong gravitational lensing (SGL) systems have been discovered in the last two decades with the advent of powerful new space and ground-based telescopes. The effect of the lens mass model (usually the power-law mass model) on…
Recent cosmological observations indicate that the present universe is flat and dark energy dominated. In such a universe, the calculation of the luminosity distance, d_L, involve repeated numerical calculations. In this paper, it is shown…
The basic cosmological distances are linked by the Etherington cosmic distance duality relation, $\eta (z) = D_{L}(z)(1+z)^{-2}/D_{A}(z) \equiv 1$, where $D_{L}$ and $D_{A}$ are, respectively, the luminosity and angular diameter distances.…
The luminosity distance-redshift relation is one of the fundamental tools of modern cosmology. We compute the luminosity distance-redshift relation in a perturbed flat matter-dominated Universe, taking into account the presence of…
In this paper we analyse the implications of the latest cosmological data sets to test the Etherington's distance duality relation (DDR), which connects the luminosity distance $D_L$ and angular diameter distance $D_A$ at the same redshift.…
In this study, we used geometric distances at high redshifts (both luminosity and angular) to perform a cosmographic analysis with the Pad\'e method, which stabilizes the behaviour of the cosmographic series in this redshift regime.…
In metric theories of gravity with photon number conservation, the luminosity and angular diameter distances are related via the Etherington relation, also known as the distance-duality relation (DDR). A violation of this relation would…
We present a joint test of cosmic curvature, $\Omega_{k0}$, and the cosmic distance-duality relation (CDDR) using the Etherington relation, which connects the luminosity and angular diameter distances at the same redshift. In this work, we…
In this letter we propose a new and model-independent cosmological test for the distance-duality (DD) relation, \eta=D_{L}(z)(1+z)^{-2}/D_{A}(z)=1, where D_{L} and D_{A} are, respectively, the luminosity and angular diameter distances. For…
We present a model independent method to test the consistency between cosmological measurements of distance and age, assuming the distance duality relation. We use type Ia supernovae, baryon acoustic oscillations, and observational Hubble…
As an exact result required by the Etherington reciprocity theorem, the cosmic distance duality relation (CDDR), $\eta(z)=D_L(z)(1+z)^{-2}/D_A(z)=1$ plays an essential part in modern cosmology. In this paper, we present a new method…
The most recent cosmological observations indicate that the present universe is flat and vacuum dominated. In such a universe, the distance measurements are always difficult and involve numerical computations. In this paper, it is shown…
The nature of the dark matter in the Universe is one of the hardest unsolved problems in modern physics. Indeed, on one hand, the overwhelming indirect evidence from astrophysics seems to leave no doubt about its existence; on the other…
A validation of the cosmic distance-duality relation (CDDR) is crucial because any observational departure from it could be a signal of new physics. In this work, we explore the potentialities of luminosity distance data from the…