Related papers: Equivalence Principle tests, Equivalence theorems …
There is a growing interest for the search of new light gauge bosons. The small mass of a new boson can turn various kinds of low-energy experiments to a new discovery machine, depending on their couplings to the standard model particles.…
Precision gauge coupling unification is one of the primary quantitative successes of low energy or split supersymmetry. Preserving this success puts severe restrictions on possible matter and gauge sectors that might appear at…
The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a…
If a new light boson existed, it would mediate a new force between ordinary fermions, like neutrons. In general such a new force is described by the Compton wavelength $\lambda_c$ of the associated boson and a set of dimensionless coupling…
These are notes on the square root of $4\times4$ identity matrix and associated quantum fields of spin one half. The method is illustrated by constructing a new mass dimension one bosonic field. The locality constraint for the field leads…
Interest has focussed recently on low energy implications of a nontrivial scale invariant sector of an effective field theory with an IR fixed point, manifest in terms of ``unparticles'' with peculiar properties. If unparticle stuff exists…
The exchange of light pseudoscalar quanta between fermions leads to long-range spin-dependent forces in order g^2, where g is the pseudoscalar-fermion coupling constant. We demonstrate that laboratory bounds on the Yukawa couplings of…
On the basis of the coincidence of the physical dimensions (in natural units $\hbar = c = 1$) of the Newton's gravitational constant $G_{N} $ and the phenomenological Fermi constant $G_{F} $ for weak interaction, it is suggested that there…
Hitherto unknown elementary particles can be searched for with atomic spectroscopy. We conduct such a search using a potential that results from the longitudinal polarization of a pseudovector particle. We show that such a potential,…
Higher-dimensional theories of the kind which may unify gravitation with particle physics can lead to significant modifications of general relativity. In five dimensions, the vacuum becomes non-standard, and the Weak Equivalence Principle…
We present a phenomenological constraint on a pseudovector light boson beyond the Standard Model, which can induce a long-range spin-dependent interaction $\alpha^{\prime\prime}({\bf s}_1\cdot{\bf s}_2)\,{\rm e}^{-\lambda r}/r$. In the…
Supersymmetric Grand Unified Theories have a rich spectrum of particles barely heavier than the intermediate vector bosons. As their non-supersymmetric counterparts, they lead to many relations among low energy observables. But the precise…
It is shown by the author that if gravitons are super-strong interacting particles and the low-temperature graviton background exists, the basic cosmological conjecture about the Dopplerian nature of redshifts may be false. In this case, a…
We consider the possibility of using measurements of anomalous magnetic moments of elementary particles as a possible test of the Einstein Equivalence Principle (EEP). For the class non-metric theories of gravity described by the \tmu…
Powerful general arguments allow only a few families of long-range interactions, exemplified by gauge field theories of electromagnetism and gravity. However, all of these arguments presuppose that massless fields have zero spin scale…
We consider the effect of a long range, flavor changing tensor interaction of possible gravitational origin. Neutrino mixing experiments provide the most sensitive probe to date for such forces---testing the equivalence principle at levels…
We study the effects of the tensor force, present in modern effective nucleon-nucleon interactions, in the spin instability of nuclear and neutron matter. Stability conditions of the system against certain very low energy excitation modes…
Charged spin 1 (vector) particles behave very differently from electrons or scalars in a Coulomb field. For an infinitely heavy point-like nucleus their bound state wave functions fall to the centre, and embedding the system in a…
The observation of a new particle in the search for the Standard Model (SM) Higgs boson at the LHC, reported by the ATLAS and CMS collaborations, is a milestone in the quest to understand electroweak symmetry breaking. The evidence at the…
We consider possible tests of the Einstein Equivalence Principle for physical systems in which quantum-mechanical vacuum energies cannot be neglected. Specific tests include a search for the manifestation of non-metric effects in Lamb-shift…