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The recent robust and homogeneous analysis of the worlds supernova distance-redshift data, together with cosmic microwave background and baryon acoustic oscillation data, provides a powerful tool for constraining cosmological models. Here we examine particular classes of scalar field, modified gravity, and phenomenological models to assess whether they are consistent with observations even when their behavior deviates from the cosmological constant Lambda. Some models have tension with the data, while others survive only by approaching the cosmological constant, and a couple are statistically favored over LCDM. Dark energy described by two equation of state parameters has considerable phase space to avoid Lambda and next generation data will be required to constrain such physics.
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In this paper, we have investigated $Lambda$CDM type cosmological model in Heckmann-Schucking space-time, by using 287 high red shift ($ .3 leq z leq 1.4$ ) SN Ia data of observed absolute magnitude along with their possible error from Union 2.1 compilation. We have used $chi^{2}$ test to compare Union 2.1 compilation observed data and corresponding theoretical values of apparent magnitude $(m)$. It is found that the best fit value for $(Omega_{m})_0$, $(Omega_{Lambda})_0$ and $(Omega_{sigma})_0$ are $0.2940$, $0.7058$ and $0.0002$ respectively and the derived model represents the features of accelerating universe which is consistent with recent astrophysical observations.
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This paper explores new evaluation perspectives for image captioning and introduces a noun translation task that achieves comparative image caption generation performance by translating from a set of nouns to captions. This implies that in image captioning, all word categories other than nouns can be evoked by a powerful language model without sacrificing performance on n-gram precision. The paper also investigates lower and upper bounds of how much individual word categories in the captions contribute to the final BLEU score. A large possible improvement exists for nouns, verbs, and prepositions.
Any new neutrino physics at the TeV scale must include a suppression mechanism to keep its contribution to light neutrino masses small enough. We review some seesaw model examples with weakly broken lepton number, and comment on the expected effects at large colliders and in neutrino oscillations.
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