• T ∼ 10−4 eV, t ∼ 1010 yr: today; baryons and the CMB are entirely decoupled, stars and galaxies have been around a long time, and clusters of galaxies (gravitationally bound systems of ∼ 1000s of galaxies) are becoming common. • T ∼ 10−3 eV, t ∼ 109 yr; the first stars and (small) galaxies begin to form. • T ∼ 10−1−2 eV, t ∼ millions of years: baryon drag ends; at earlier times, the baryons a...

This paper presents data from the BIMA interferometer showing spatially resolved absorption spectra of the gravitationally lensed quasar PKS 1830-211. High-resolution (1.2 km s) spectra were taken in two spectral windows centered on the redshifted frequencies of the HCO(2 ← 1) and HCN(2 ← 1) molecular transitions. There is no molecular absorption in the northeast image but the southwest image r...

We construct a family of semi-analytic models for young open clusters, including a gaseous component and varying assumptions about the distribution function for the stellar component. The parameters of these models are informed by observed open clusters and general theoretical considerations regarding cluster formation. We use this framework to estimate the fraction F∗ of the stellar component ...

In the present paper we show how obtain the energy distribution f(E) in our vicinity starting fromWIMP density profiles in a self consistent way by employing the Eddington approach and adding reasonable angular momentum dependent terms in the expression of the energy. We then show how we can obtain the velocity dispersions and the asymmetry parameter ]beta in terms of the parameters describing ...

We investigate the ratio of gravitational binding energy to rest mass in general relativity. For N pointlike masses, an upper bound on the magnitude of this ratio can be derived using the second law of black hole dynamics. Only as N approaches infinity can the ratio approach one. A configuration that saturates the N = ∞ bound is a thin spherical shell as its radius is taken to zero. This system...

We investigate the ratio of gravitational binding energy to rest mass in general relativity. For N pointlike masses, an upper bound on the magnitude of this ratio can be derived using the second law of black hole dynamics. Only as N approaches infinity can it approach one. A configuration that saturates the N = ∞ bound is a thin spherical shell as its radius is taken to zero. This system provid...

In this paper, we discuss a possibility to improve constraints on spin-dependent short-range interactions in the range of 1 – 200μm significantly. For such interactions, our constraints are without competition at the moment. They were obtained through the observation of gravitationally bound states of ultracold neutrons. We are going to improve these constraints by about three orders of magnitu...

Previous studies of gravitationally bound states of ultracold neutrons showed the quantization of energy levels, and confirmed quantum mechanical predictions for the average size of the two lowest energy states wave functions. Improvements in position-like measurements can increase the accuracy by an order of magnitude only. We therefore develop another approach, consisting in accurate measurem...

Abstract. A dynamically preferred quasi-local definition of gravitational energy is given in terms of the Hamiltonian of a ‘2+2’ formulation of general relativity. The energy is well-defined for any compact orientable spatial 2-surface, and depends on the fundamental forms only. The energy is zero for any surface in flat spacetime, and reduces to the Hawking mass in the absence of shear and twi...

It is well-known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special...