32,078 research outputs found
Non-dopplerian cosmological redshift parameters in a model of graviton-dusty universe
Possible effects are considered which would be caused by a hypothetical
superstrong interaction of photons or massive bodies with single gravitons of
the graviton background. If full cosmological redshift magnitudes are caused by
the interaction, then the luminosity distance in a flat non-expanding universe
as a function of redshift is very similar to the specific function which fits
supernova cosmology data by Riess et al. From another side, in this case every
massive body, slowly moving relatively to the background, would experience a
constant acceleration, proportional to the Hubble constant, of the same order
as a small additional acceleration of Pioneer 10, 11.Comment: 5 pages. It was presented: at SIGRAV'2000 Congress, Italy (this
version); in Proc. of the Int. Symp. "FFP 4" (9-13 Dec 2000, Hyderabad,
India), Sidharth& Altaisky, Eds., Kluwer Academic/Plenum, 2001;in Proc. of
the 4th Edoardo Amaldi Conference on GW (Perth, W. Australia, 8-13 July 2001
On kaonic deuterium. Quantum field theoretic and relativistic covariant approach
We study kaonic deuterium, the bound K^-d state A_(K d). Within a quantum
field theoretic and relativistic covariant approach we derive the energy level
displacement of the ground state of kaonic deuterium in terms of the amplitude
of K^-d scattering for arbitrary relative momenta. Near threshold our formula
reduces to the well-known DGBT formula. The S-wave amplitude of K^-d scattering
near threshold is defined by the resonances Lambda(1405), Sigma(1750) and a
smooth elastic background, and the inelastic channels K^- d -> NY and K^- d ->
NY pion, with Y = Sigma^(+/-), Sigma^0 and Lambda^0, where the final-state
interactions play an important role. The Ericson-Weise formula for the S-wave
scattering length of K^-d scattering is derived. The total width of the energy
level of the ground state of kaonic deuterium is estimated using the
theoretical predictions of the partial widths of the two-body decays A_(Kd) ->
NY and experimental data on the rates of the NY-pair production in the
reactions K^-d -> NY. We obtain Gamma_{1s} = (630 +/-100) eV. For the shift of
the energy level of the ground state of kaonic deuterium we predict
epsilon_(1s) = (353 +/-60)eV.Comment: 73 pages,10 figures, Latex, We have slightly corrected the
contribution of the double scattering. The change of the S-wave scattering
length of K^-d scattering does not go beyond the theoretical uncertainty,
which is about 18
Systematic treatment of non-linear effects in Baryon Acoustic Oscillations
In this contribution we will discuss the non-linear effects in the baryon
acoustic oscillations and present a systematic and controllable way to account
for them within time-sliced perturbation theory.Comment: 8 pages, 5 figures; to appear in the Proceedings of the 19th
International Seminar on High Energy Physics QUARKS-2016, Pushkin, Russia, 29
May - 4 June, 201
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