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Related papers: MACHO Messages from the Big Bang

200 papers

The Cosmic Microwave Background Radiation (CMBR) is the radiation left over from the hot Big Bang. Its blackbody spectrum and small anisotropy provide clues about the origin and early evolution of the Universe. In particular, the spectrum…

Astrophysics · Physics 2007-05-23 Edward L. Wright

An initial state for the observable universe consisting of a finite region with a large vacuum energy will break-up due to near horizon quantum critical fluctuations. This will lead to a Friedmann-like early universe consisting of an…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-04 George Chapline

We consider the production of primordial micro black holes (MBH) remnants in the early universe. These objects induce the universe to be in a matter-dominated era before the onset of inflation. Effects of such an epoch on the CMB power…

General Relativity and Quantum Cosmology · Physics 2011-03-22 Fabio Scardigli , Christine Gruber , Pisin Chen

We study black hole MACHO binary formation through three-body interactions in the early universe at $t\sim 10^{-5}$s. The probability distribution functions of the eccentricity and the semimajor axis of binaries as well as of the…

Astrophysics · Physics 2009-10-30 Kunihito Ioka , Takeshi Chiba , Takahiro Tanaka , Takashi Nakamura

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic…

In this paper, we show that the initial clustering of supermassive primordial black holes (SMPBHs) beyond a Poisson distribution can efficiently enhance the matter power spectrum, and thus the halo mass function. As a result, the population…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-23 Hai-Long Huang , Jun-Qian Jiang , Yun-Song Piao

Seven observations point towards the existence of primordial black holes (PBH), constituting the whole or an important fraction of the dark matter in the Universe: the mass and spin of black holes detected by Advanced LIGO/VIRGO, the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-30 Sebastien Clesse , Juan García-Bellido

Earth-mass dark matter microhalos with size of ~100 AUs are the first structures formed in the universe, if the dark matter of the Universe are made of neutralino. Here, we report the results of ultra-high-resolution simulations of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-09 Tomoaki Ishiyama , Junichiro Makino , Toshikazu Ebisuzaki

Most of the mass density in the Universe---and in the halo of our own galaxy---exists in the form of dark matter. Overall, the contribution of luminous matter (in stars) to the mass density of the Universe is less than 1\%; primordial…

Astrophysics · Physics 2009-09-25 Michael S. Turner

Neutralino dark matter leads to the formation of numerous earth mass dark matter haloes at redshifts z\approx 60 (Diemand et al. 2005). These abundant CDM micro-haloes have cuspy density profiles that can easily withstand the Galactic tidal…

Astrophysics · Physics 2007-05-23 Ben Moore , Juerg Diemand , Joachim Stadel , Thomas Quinn

The emerging empirical picture of galaxy stellar mass (Ms) assembly shows that galaxy population buildup proceeds from top to down in Ms. By connecting galaxies to LCDM halos and their histories, individual (average) Ms growth tracks can be…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-01 V. Avila-Reese , C. Firmani

Recently the French EROS collaboration and the American-Australian MACHO collaboration have reported the observation of altogether three possible microlensing events by monitoring over several years the brightness of millions of stars in…

Astrophysics · Physics 2009-10-22 Philippe Jetzer , Eduard Masso

The recent detection by Advanced LIGO of gravitational waves (GW) from the merging of a binary black hole system sets new limits on the merging rates of massive primordial black holes (PBH) that could be a significant fraction or even the…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-03 Sebastien Clesse , Juan García-Bellido

We address the issue of the cosmological bias between matter and galaxy distributions, looking at dark-matter haloes as a first step to characterize galaxy clustering. Starting from the linear density field at high redshift, we follow the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Anna Elia , Suchita Kulkarni , Cristiano Porciani , Massimo Pietroni , Sabino Matarrese

It is argued that the data presented by Hubble Space Telescope and James Webb Space Telescope, that seem to be at odds with the canonical big bang cosmology, find simple explanation if galaxy formation is seeded by massive primordial black…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-07 A. D. Dolgov

Modified matter power spectra with approximately Gaussian bump on sub-Mpc scales can be a result of a complex inflation. We consider five spectra with different Gaussian amplitudes $A$ and locations $k_0$ and run N-body simulations in a…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-15 M. V. Tkachev , S. V. Pilipenko , E. V. Mikheeva , V. N. Lukash

The French collaboration EROS and the American-Australian collaboration MACHO have reported the observation of altogether $\sim$ 10 microlensing events by monitoring during several years the brightness of millions of stars in the Large…

Astrophysics · Physics 2011-04-15 Philippe Jetzer

In this letter, we report precise and robust observational constraints on dark matter-dark energy scattering cross section, using the latest data from cosmic microwave background (CMB) Planck temperature and polarization, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-06 Suresh Kumar , Rafael C. Nunes

Even if massive ($10\,M_\odot \lesssim M \lesssim 10^4 M_\odot$) primordial black holes (PBHs) can only account for a small fraction of the dark matter (DM) in the universe, they may still be responsible for a sizable fraction of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-27 Pasquale D. Serpico , Vivian Poulin , Derek Inman , Kazunori Kohri

Ultracompact minihalos have recently been proposed as a new class of dark matter structure. These minihalos would be produced by phase transitions in the early Universe or features in the inflaton potential, and constitute non-baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Pat Scott , Sofia Sivertsson