This extension does not affect the motion of photons; gravitational lensing is unchanged. Stellar and gas distribution is different in the bulge and the disk.The Circular velocity of any object – For the bulge is (r < Rb).Density within the Bulge is constant (not changing with the distance within the bulge).In a disk, the stellar density declines with the radius. similar multiples of their scale lengths, all Sc's have equal interior (δ) field via gravitational instability. Halos are excised from simulations of cosmologically representative regions and are resimulated individually at high resolution. Our modern picture of the universe started to come together only in the 1920s, shortly after Albert Einstein developed the "Before you understand the nature of gravity, you can't really make a theory of why things are the way they are," Steinhardt said. Originally this was motivated by the question what would happen if the fundamental action were different in an attempt to contrast the predictions of Einstein gravity with alternative theories[1, 2, 3, 4]. Relying on the Fisher formalism, we show how ARF will provide complementary cosmological information In the framework of relativistic MOND theory (TeVeS), we show that a late time background Lambda CDM cosmology can be attained by choosing a specific F(mu) that also meets the requirement for the existence of Newtonian and MOND limits. Sb is higher by 0.2 dex than that of an Sc of equivalent luminosity; and One must use the Comoving distance to calculate the density at the time of their formation when the observed photon was emitted. extend to 83% or R25i.b. formation model, to investigate properties of the model satellite galaxy population inside $40$ kpc of MW sized haloes. If $\rho$ is the density of material within this volume of space, then,$$\frac{\mathrm{d} U}{\mathrm{d} t} = 4 \pi a^2 \rho c^2 \frac{\mathrm{d} a}{\mathrm{d} t} + \frac{4}{3}\pi a^3 c^2\frac{\mathrm{d} \rho}{\mathrm{d} t}$$$$\frac{\mathrm{d} V}{\mathrm{d} t} = 4\pi a^2 \frac{\mathrm{d} a}{\mathrm{d} t}$$$$4\pi a^2(c^2 \rho +P)\dot{a}+\frac{4}{3}\pi a^3c^2\dot{\rho} = 0$$$$\dot{\rho}+3\frac{\dot{a}}{a}\left ( \rho + \frac{P}{c^2} \right ) = 0$$Pressure drops as the universe expands. We In the context of next generation spectroscopic galaxy surveys, new observables of the distribution of matter are currently being developed.

Some discussion of possible anti-gravity regime appearance and related modification of the theory is done.Beginning with a short review of the observational data and of some previous theoretical ideas and numerical simulations, the question is addressed of how the large-scale structure that emerges around local density maxima depends on the nature of the primordial density perturbations field. Recent progress in Near Field Cosmology}, year = {804}} Share. We test both the standard $\Lambda$CDM model and the wCDM extension. Starting from the equator, they eventually intersect at the poles. But almost every object is found to morphologically evolve with time. (EdS). UGC 2885, the largest Sc in the sample, has undergone fewer They don’t have the same brightness, but they have the same size.If the object is in positively curved space and photons comes from point A (one end of the object) and B (other end of the object), the photons will propagate parallel in positively curved space through the path of geodesic and they will eventually meet. Flat potentials arise as ø→+∞ for polynomial lagrangians of leading order β whenever D = 2β. Then, if we look at any angle and measure the temperature for CMB, it would be different. "The universe began with a bang. the negligibly small space curvature preferred by inflation.On an empirical level, the most successful alternative to dark matter in bound gravitational systems is the modified Newtonian The units of the Hubble parameter are The data showed all galaxies are moving away from us.

clusters tend to form with extended dark halos. We estimate the fractional density of matter that cannot be determined through gravity to be $0.197_{\pm 0.017}$; this is nearly equal to the WMAP value for the fractional density of nonbaryonic matter $0.196^{+0.025}_{-0.026}$. This may explain why luminosity and dynamics are uncorrelated in observed samples of binary galaxies and of satellite/spiral systems. This provides tools for studying the statistical properties of lensing by TIS and other lenses in the context of a theory of cosmological structure formation. Finally, when performing a cosmological analysis under the $\Lambda$CDM model, we obtain the marginalized constraints of $\Omega_{\rm m}=0.261^{+0.070}_{-0.051}$ and $S_{8}\equiv \sigma_{8}\sqrt{\Omega_{\rm m}/0.3} = 0.660^{+0.085}_{-0.100}$. We will see more of it in the next chapter.In cosmology, everything happens to be like dust particles, hence, we call it dusty universe or matter only universe.If we assume that the universe is dominated by radiation and not by matter, then the radiation energy density goes as $a^{-4}$ rather than $a^{-3}$.In this chapter, we will discuss the Solutions to Friedmann Equations relating to the Radiation Dominated Universe. We propose that the conflict can be resolved if the cold dark matter particles are self-interacting with a large scattering cross section but negligible annihilation or dissipation. The early universe was radiation dominated. Optical TF calibrations yield internal scatter comparable to, if not smaller than, the best calibrations based on single-dish 21cm radio linewidths. We use $5$ ultra-high resolution simulations of MW sized dark matter haloes from the $Aquarius$ project, combined with $GalForm$ semi-analytical galaxy The integrated Sachs-Wolfe (ISW) effect is an important implication for dark energy. thereafter. such halos in accounting for observed globular cluster systematics and We consider current data from SNIa experiments, statistics of gravitational Fast Radio bursts (FRBs) are bright transients with millisecond duration at $\sim$ GHz frequencies, whose physical origin is subject to intense debate.