A. B. Kaganovich

Dynamical measure and field theory models free of the cosmological constant problem

Summary of abstract Field theory models including gauge theories with SSB are presented where the energy density of the true vacuum state (TVS) is zero without fine tuning. The above models are constructed in the gravitational theory where a measure of integration \Phi in the action is not necessarily \sqrt{-g} but it is determined dynamically through additional degrees of freedom. The ratio \Phi/\sqrt{-g} is a scalar field which can be solved in terms of the matter degrees of freedom due to the existence of a constraint. We study a few explicit field theory models where it is possible to combine the solution of the cosmological constant problem with: 1) possibility for inflationary scenario for the early universe; 2) spontaneously broken gauge unified theories (including fermions). The models are free from the well known problem of the usual scalar-tensor theories in what is concerned with the classical GR tests. The only difference of the field equations in the Einstein frame from the canonical equations of the selfconsistent system of Einsteins gravity and matter fields, is the appearance of the effective scalar field potential which vanishes in TVS without fine tuning.

Principle of nongravitating vacuum energy and some of its consequences.

For Einsteins General Relativity (GR) or the alternatives suggested up to date

String and brane models with spontaneously or dynamically induced tension

the vacuum energy gravitates. We present a model where a new measure is introduced for integration of the total action in the D-dimensional space-time. This measure is built from D scalar fields

Gravitational Theory Without the Cosmological Constant Problem

\varphi_{a}

Asymptotically de Sitter and anti-de Sitter Black Holes with Confining Electric Potential

. As a consequence of such a choice of the measure, the matter lagrangian

Variable-tension lightlike brane as a gravitational source of traversable Misner–Wheeler-type wormholes

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Einstein–Rosen “bridge” needs lightlike brane source

can be changed by adding a constant while no gravitational effects, like a cosmological term, are induced. Such Non-Gravitating Vacuum Energy (NGVE) theory has an infinite dimensional symmetry group which contains volume-preserving diffeomorphisms in the internal space of scalar fields

Absence of the fifth force problem in a model with spontaneously broken dilatation symmetry

\varphi_{a}

EXOTIC LOW DENSITY FERMION STATES IN THE TWO MEASURES FIELD THEORY: NEUTRINO DARK ENERGY

. Other symmetries contained in this symmetry group, suggest a deep connection of this theory with theories of extended objects. In general {\em the theory is different from GR} although for certain choices of

Weyl-conformally-invariant lightlike p-brane theories: New aspects in black hole physics and Kaluza-Klein dynamics

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