http://popups.lib.uliege.be/1373-5411/index.php?id=1261 Publications of Auteurs Branko Novakovic fr 0 http://popups.lib.uliege.be/1373-5411/index.php?id=3904 The notion of an alpha field has been associated to any potential field that can be presented by two dimensionless field parameters α and α'. The problem in this paper is to derive the generalized metrics in the Relativistic Alpha Field Theory (RAFT). In that sense, it is started with the new General Lorentz Transformation model in an alpha field (GLTα - model) derived by employing the well known group postulates and isotropy of the space. It follows the derivation of the general line element and the related general metric tensor in an alpha field both in the Minkowski and Riemannian metrics. The one section of the paper is devoted to derivation of a general diagonal form of a line element and metric tensor in an alpha field. It has been shown that there exists a simple coordinate transformation procedure in an alpha field that transforms the Riemannian metrics into the Minkowski one and vice versa. Tue, 01 Oct 2024 14:01:03 +0200 Tue, 01 Oct 2024 14:01:14 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=3904 http://popups.lib.uliege.be/1373-5411/index.php?id=2825 The problem is to explain the real physical source of the dark energy and what the value of the rate of the expansion is. In that sense, the analytical expression of Λ= (GM/r2c2)2 has been derived as the function of the universe mass M and radius r. Meanwhile, the Einstein's field equations require that A should be a constant. Therefore, the structure of the universe should include a new mass-radius balancing constant Kmr = M/r2, with the consequence that universe mass is producing proportional to r2. Related scalar field, determined by A, is the real physical source of the dark energy. The velocity and acceleration equations show the value of the rate of the accelerated expansion. Thus, this model solves the dark energy problem, the initial singularity problem and gives a unique solution: a closed universe. It should be verified by the observation data. Tue, 03 Sep 2024 14:58:01 +0200 Tue, 03 Sep 2024 14:58:12 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=2825 http://popups.lib.uliege.be/1373-5411/index.php?id=2378 The proposed model of the universe motion gives some new specific answers to the important questions of the cosmology: what occurred at the initial singularity?, how old is the universe?, how big is the universe?, and what is it's ultimate fate? This new approach is based on the new solution of the Einstein's field equations in a vacuum. This solution confirms that the so called cosmological constant, ʌ, is not really constant, but a function of the gravitational radius. As the consequence, the acceleration equation of the universe motion shows that the universe acceleration can be attractive (negative) or repulsive (positive). The repulsive acceleration gives rise to the accelerating expansion of the universe at the present time. The change from the contracting phase into the expanding one, takes place at the minimal radius,r=GM/2c². This could be the solution of the initial singularity. Fri, 02 Aug 2024 11:51:44 +0200 Fri, 02 Aug 2024 11:51:51 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=2378 http://popups.lib.uliege.be/1373-5411/index.php?id=1726 Because a scalar potential of a gravitational field has a unit of a specific energy (J/kg), the problem of unification of potential fields has been transformed into the problem of unification of specific potential energies of a particle in a multi-potential field. Consequently, the parameter α and α' of GLT model become the functions of a unified specific potential energy in a multi-potential field. Since all items like field tensors and Klein, Gordon and Fock equation are functions of parameters α and α', these items can be applied to multi-potential fields. Thus, a field tensor of a unified specific potential energy of a particle in central symmetric electromagnetic and gravitational fields in vacuum is derived. Finally, it has been shown that a momentum equation of photons will remain unchanged even if the photons may have the mass. Tue, 16 Jul 2024 14:18:53 +0200 Tue, 16 Jul 2024 14:19:03 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=1726 http://popups.lib.uliege.be/1373-5411/index.php?id=1255 A new General Lorentz Transformation model (GLT-model) derived by Novakovic ( 1999) for the particle motion in x-axis only, has been extended to the full form including y and z - axes. Starting with this transformation model, a general line element and a corresponding general metric tensor of GLT - model have been derived. The general line element and the metric tensor are functions of two free parameters α and α' , which are the functions of the space-time coordinates. The identification of two free parameters of GLT-model has been done for a weak and a strong gravitational field. The weak gravitational field solution of the two free parameters of GLT-model corresponds to the well-known Schwartzschild's metrics of the line element, for a spherically symmetric non-rotating body. It is very important to point out that the line element of GLT-model given in a non-diagonal form has got a very important property: non-singularity in a very strong gravitational field. Finally, a simple coordinate transformation procedure has been derived that transforms a general line element into diagonal one, with metric components (-1, 1, 1, 1), equal to the metrics in Special Relativity. Since the all items in SR and GR can be described as the functions of two free parameters of GLT-model, the possibilities of an unification of Einstein's Special and General Theories of Relativity, as well as a new unification of electromagnetic and gravitational fields are opened. Wed, 10 Jul 2024 09:47:56 +0200 Mon, 07 Oct 2024 15:44:23 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=1255