相关论文: Is Cold Dark Matter Baryonic? Alternative Opinion
Several lines of evidence suggest that some of the dark matter may be non-baryonic: the non-detection of various plausible baryonic candidates for dark matter inferred, e.g., from galaxy rotation curves and from cluster of galaxy velocity…
We know from cosmological and astrophysical observations that more than 80% of the matter density in the Universe is non-luminous, or dark. This non-baryonic dark matter could be composed of neutral, heavy particles, which were…
Motivated by inflation, the theory of big-bang nucleosynthesis and the quest for a deeper understanding of the fundamental forces and particles, a very successful paradigm for the development of structure in the Universe has evolved. It…
The Hot Big Bang is often considered as the origin of all matter and radiation in the Universe. Primordial nucleosynthesis (BBN) provides strong evidence that the early Universe contained a hot plasma of photons and baryons with a…
More than 90% of matter in the Universe could be composed of heavy particles, which were non-relativistic, or 'cold', when they froze-out from the primordial soup. I will review current searches for these hypothetical particles, both via…
The dark matter problem is almost a century old. Since the 1930s evidence has been growing that our cosmos is dominated by a new form of non-baryonic matter, that holds galaxies and clusters together and influences cosmic structures up to…
Cosmological nucleosynthesis calculations imply that there should be both non-baryonic and baryonic dark matter. Recent data suggest that some of the non-baryonic dark matter must be "hot" (i.e. massive neutrinos) and there may also be…
Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious "dark matter" component, which does not interact via electromagnetism and thus neither…
It is proposed that when the era of the big-bang nucleosynthesis ended, almost all of the 75 percent of the observed total baryonic matter remained in the form of hydrogen and continued to exist in the form of protons and electrons. They…
In currently popular cosmological scenarios -- all variants of the cold dark matter (CDM) cosmogony -- some time beyond a redshift of 15, stars within the numerous small halos that condense with virial temperatures ~1e4 K created the first…
Matter in the universe has become ``dark'' or ``missing'' through misconceptions about the fluid mechanics of gravitational structure formation. Gravitational condensation occurs on non-acoustic density nuclei at the largest Schwarz length…
Big-Bang nucleosynthesis (BBN) represents one of the earliest phenomena that can lead to observational constraints on the early Universe properties. It is well-known that many important mechanisms and phase transitions occurred before BBN.…
The nature of the dark matter in the Universe is one of the outstanding questions in astrophysics. In this talk, I address possible stellar baryonic contributions to the 50-90% of our Galaxy that is made of unknown dark matter. First I show…
The recently observed Deuterium abundance in a low- metallicity high-redshift hydrogen cloud, which is about ten times larger than that observed in the near interstellar medium, is that expected from the Standard Big Bang Nucleosynthesis…
One of the greatest mysteries in astrophysics and cosmology is the nature and the origin of cold dark matter, which represents more than 84% of the mass in the universe. Dark matter reacts on and produces gravitational forces and governs…
Observations of quasar microlensing by Schild 1996 show the baryonic dark matter BDM of galaxies is micro-brown-dwarfs, primordial hydrogen-helium planets formed at the plasma to gas transition 10^13 seconds, in trillion-planet clumps…
Dark matter appears in two forms as a consequence of the fluid mechanics of self-gravitational condensation. Condensation occurs primarily on non-acoustic nuclei rather than on the acoustic nuclei of the Jeans (1902) criterion, leading to a…
[A brief review intended for a general physics colloquium audience.] Astrophysicists now know that 80% of the matter in the universe is `dark matter', composed of neutral and weakly interacting elementary particles that are not part of the…
The evidence for the existence of dark matter in the universe is reviewed. A general picture emerges, where both baryonic and non-baryonic dark matter is needed to explain current observations. In particular, a wealth of observational…
There are multiple examples of gravitational losses in neutron stars and black holes. Protons and neutrons have been found to have enormous repulsive pressures that highly squeezed collapsing matter cannot overcome. The case against…