We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter (ψDM), described by the Schrödinger-Poisson (SP) equation with a particle mass ∼ 10 −22 eV. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass (Mc) and haloh , where a is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of a statistical sample of virialized halos that form in our 3D cosmological simulations, and by (ii) merging multiple solitons to create individual virialized objects. Sufficient simulation resolution is achieved by adaptive mesh refinement and graphic processing units acceleration. From this scaling relation, present dwarf satellite galaxies are predicted to have kpc sized cores and a minimum mass of ∼ 10 8 M⊙, capable of solving the small-scale controversies in the cold dark matter model. Moreover, galaxies of 2 × 10 12 M⊙ at z = 8 should have massive solitonic cores of ∼ 2 × 10 9 M⊙ within ∼ 60 pc. Such cores can provide a favorable local environment for funneling the gas that leads to the prompt formation of early stellar spheroids and quasars.PACS numbers: 03.75. Lm, 95.35.+d, 98.56.Wm, 98.62.Gq Accumulating evidences suggest that the Universe contains ∼ 26% dark matter [1] which interacts primarily through self-gravity. Dark matter comprising very light bosons with a mass m ψ ∼ 10 −22 eV has been recognized as a viable means of suppressing low mass galaxies and providing cored profiles in dark matter dominated galaxies [2,3]. Interestingly, this boson mass scale can naturally arise in a non-QCD axion model [4], lending support for the very light boson. The relative deficiency of the observed number of low-mass galaxies is a major problem for standard cold dark matter (CDM) [5][6][7], for which a steeply rising mass function is predicted [8]. Furthermore, the dwarf spheroidal galaxies [9-20] and low surface brightness galaxies [21,22] are generally inferred to have large flat cores of dark matter, at odds with the singular cores required by standard CDM [23,24]. Complicated baryonic physics such as supernova feedback is required to solve both issues in the CDM paradigm [25][26][27][28][29][30][31][32][33][34].Extremely light bosonic dark matter can be assumed to be non-thermally generated and described by a single coherent wave function [2,[35][36][37][38], which we term ψDM. Here solutions to both the missing-satellite and ...

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It is the common consensus that the expansion of a universe always slows down if the gravity provided by the energy sources therein is attractive and accordingly one needs to invoke dark energy as a source of anti-gravity for understanding the cosmic acceleration. To examine this point we find counter-examples for a spherically symmetric dust fluid described by the Lemaitre-TolmanBondi solution without singularity. Thus, the validity of this naive consensus is indeed doubtful and the effects of inhomogeneities should be restudied. These counter-intuitive examples open a new perspective on the understanding of the evolution of our universe.

As stimulated by earlier attempts for obtaining the rtNN and rrNA form factors from the deep inelastic lepton scattering data, we extend the analysis by taking into account effects of additional mesons including p, o9, o-, K, and K*, with the coupling constants fixed by the lowenergy nucleon-nucleon and hyperon-nucleon scattering data. Contrary to an earlier claim that the lr NN and 7rNA form factor must be very soft (e.g., with the cutoff mass less than 500 MeV in the monopole form), we find, for example, that with all form factors parametrized in the dipole form, a universal cutoff mass of 1150 MeV in the

In light of the recent observations of type Ia supernovae suggesting an accelerating expansion of the Universe, we wish in this paper to point out the possibility of using a complex scalar field as the quintessence to account for the acceleration. In particular, we extend the idea of Huterer and Turner in deriving the reconstruction equations for the complex quintessence, showing the feasibility of making use of a complex scalar field (instead of a real scalar field) while maintaining the uniqueness feature of the reconstruction for two possible situations, respectively. We discuss very briefly how future observations may help to distinguish the different quintessence scenarios, including the scenario with a positive cosmological constant.Comment: 9 pages, LaTeX, final versio

We need to make a correction to our earlier work [1], namely a critical error in the relative sign between the lowest-dimensional term and the leading nonperturbative contribution. By correcting the sign error and evaluating an additional contribution which we omitted earlier, we conclude that our new prediction on the weak pion-nucleon coupling f πN N is in the vincinity of 3 × 10 −7 , and is stable.The main idea of our approach is that both the strong and parity-violating pionnucleon couplings, g πN N and f πN N , respectively, are given by the lowest dimensional diagram and by a pion vacuum susceptibility, χ π . Therefore, by using the known value of g πN N one can determine χ π and thereby predict the value of f πN N . Using definitions for the susceptibilities given in Ref.[1], the QCD sum rule for the strong πNN coupling

The QCD spectral sum rules in the presence of the external electromagnetic field F µν is used to calculate the magnetic moment of Σ c and Λ c . Our result