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It is commonly believed that the vacuum energy problem points to the need for (1) a radically new formulation of gravitational physics and (2) a new principle which forces the vacuum stress-energy tensor (as measured by gravity) to be nearly zero. Here we point out that a new fundamental theory contains both features: (1) In this theory the vierbein is interpreted as the "superfluid velocity" associated with the order parameter for a GUT-scale Higgs condensate. (2) The vacuum stress-energy tensor is exactly zero in the vacuum state, because the action is extremalized with respect to variations in the order parameter. With inhomogeneously-distributed matter present, the vacuum stress-energy tensor is shifted away from zero., Comment: 3 pages; to be published in the proceedings of the 20th Texas Symposium on Relativistic Astrophysics, edited by J. C. Wheeler and H. Martel (published by A.I.P.) The treatment in this paper is superseded by that in hep-th/0110208: Although the vacuum energy is viewed from a very different perspective in the present theory, it remains just as big a mystery as in standard field theory and superstring/M theory. (The extremum considered in this paper is not a true extremum with respect to variations in the metric tensor.)

A new cosmological model makes the following predictions: (1) The deceleration parameter $q_{0}$ is approximately zero. (2) The mass density parameter $\Omega_{m}$ is less than 1. (3) The universe is spatially closed, but is asymptotically flat as $t\to\infty$, regardless of its matter content. (4) The age of the universe is approximately 15 Gyr if the Hubble parameter $h$ is approximately 0.65., Comment: 4 pages. 2 minor changes to reconcile with the printed version

A new cosmological model leads to testable predictions that are different from those of both standard cosmology and models with a cosmological constant. The prediction that q_0=0 is the same as in other ``coasting universe'' models, but arises without the need for any exotic form of matter or other ad hoc assumptions., Comment: 4 pages, LaTeX (figure also in LaTeX). Submitted for the proceedings of PASCOS-98 (Sixth International Symposium on Particles, Strings and Cosmology; Northeastern University, Boston; March 22-27, 1998)

A new cosmological model implies that dR/dt is constant for both t > t_c and t goes to 0, and that dR^2/dt is proportional to n_s^-1 for t_c > t > 0. Here R(t) is the cosmic scale factor, t_c is a crossover time defined in the text, and n_s is approximately constant near t_c. The behavior at intermediate times is consistent with big-bang nucleosynthesis. The behavior at short and long times offers a solution to the smoothness, monopole, and flatness problems. In addition, the long-time behavior yields a comfortably large age for the universe and predicts that the deceleration parameter q_0 is exactly zero., Comment: A better picture is given in astro-ph/9902042: The dominant contribution to R(t) in the late universe is from the cosmological instanton, but Einstein gravity dominates in the early universe. This basic picture was already implicit in the original treatment of Ref. 1, hep-th/9612041