相关论文: A note on shock wave in the dark matter medium
Beginning with a geometric motivation for dark matter going back to the axioms of general relativity, we show how scalar field dark matter, which naturally forms dark matter density waves due to its wave nature, may cause the observed…
Tidal debris streams from galaxy satellites can provide insight into the dark matter distribution in halos. This is because we have more information about stars in a debris structure than about a purely random population of stars: we know…
For nearly a century, more mass has been measured in galaxies than is contained in the luminous stars and gas. Through continual advances in observations and theory, it has become clear that the dark matter in galaxies is not comprised of…
Dark matter density profiles based upon Lambda-CDM cosmology motivate an ansatz velocity distribution function with fewer high velocity particles than the Maxwell-Boltzmann distribution or proposed variants. The high velocity tail of the…
A massive astrophysical object deforms a local distribution of dark matter, resulting in a local overdensity of dark matter. This phenomenon is often referred to as gravitational focusing. In the solar system, the gravitational focusing due…
We propose a unified framework that reconciles the stunning success of MOND on galactic scales with the triumph of the LambdaCDM model on cosmological scales. This is achieved through the physics of superfluidity. Dark matter consists of…
The ubiquitous presence of dark matter in the universe is today a central tenet in modern cosmology and astrophysics. Ranging from the smallest galaxies to the observable universe, the evidence for dark matter is compelling in dwarfs,…
Using high-accuracy rotation curves of spiral galaxies, we derive distributions of the surface mass density. Comparing with the luminosity profiles, we show that the dark mass in disk and bulge distributions follows those of luminous…
We study the distribution of the Milky Way satellites stellar and dark matter debris. For the first time we address the question of the tidal disruption of satellites in simulations by utilising simultaneously a) a realistic set of orbits…
Vast sound waves traveling through the relativistic plasma during the first million years of the universe imprint a preferred scale in the density of matter. We now have the ability to detect this characteristic fingerprint in the…
The gravitational frequency shift of light signals from the center of a spherically symmetric non-static matter distribution is considered. Explicit formulas for the ratio of the emitted and received frequencies are obtained in the case of…
We study gravitational waves from a particle moving around a system of a point mass with a disk in Newtonian gravitational theory. A particle motion in this system can be chaotic when the gravitational contribution from a surface density of…
In this work, we examine the different properties of galactic satellites in hydrodynamical and pure dark matter simulations. We use three pairs of simulations (collisional and collision-less) starting from identical initial conditions. We…
It is well known that the cosmological constant term in the Einstein field equations can be interpreted as a stress tensor for dark energy. This stress tensor is formally analogous to an elastic constitutive equation in continuum mechanics.…
In this work, analyzing the propagation of electromagnetic waves in the field of gravitational waves, we show the presence and significance of the so called surfing effect for pulsar timing measurements. It is shown that, due to the…
Theoretical models of self-interacting dark matter offer a promising solution to several unresolved issues within the collisionless cold dark matter framework. For asymmetric dark matter, these self-interactions may encourage gravitational…
It has been suggested in the literature that the sound velocity of the nuclear matter $v_s$ violates the so-called sound velocity bound $v_s \le c/\sqrt{3}$ at high density, where $c$ is the speed of light. In this paper, we revisit this…
Observations show that about the 20% of the Universe is composed by invisible (dark) matter (DM), for which many candidates have been proposed. In particular, the anomalous behavior of rotational curves of galaxies (i.e. the flattening at…
On the scales of galaxies and beyond there is evidence for unseen dark matter. In this paper we find the experimental limits to the density of dark matter bound in the solar system by studying its effect upon planetary motion.
We present arguments indicating that galaxies and their clusters should be considered as open developing systems. Galaxies interact with the intergalactic medium and are not in a virial equilibrium (which is determined by the gravity and…