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Exploration of near-infrared photoactive organic molecules based on sulfone rosamine derivatives
No full text3次元リーマン多様体の等質構造
No full textWe determine all homogeneous Riemannian structures and homogeneous space representations on S2 × R, H2 × R and 3-dimensional Riemannian Lie groups. This work together with previous results yields a complete classification of all homogeneous Riemannian structures and homogeneous space representations on 3-dimensional homogeneous Riemannian manifolds: R3, H3, S3, S2 × R, H2 × R and the 3-dimensional Riemannian Lie groups
物理定数の時間変化と余剰成分に関する宇宙観測制限
No full textLambda Cold Dark Matter (ΛCDM) model, which predicts the cosmological constant Λ as dark energy and cold dark matter (CDM), has successfully explained various properties and observations of the univers. It not only explains the current accelerated expansion of the universe revealed by local observations but also explains early universe phenomena such as the Cos-mic Microwave Background (CMB) and Big Bang Nucleosynthesis (BBN), effectively describing 13.7 billion years of the universe history. However, as observational precision has improved, a discrepancy exceeding 4σ has been reported between the direct measurement of the Hubble constant from local observations and the value derived from distant observations assuming the ΛCDM model. The shorten sound horizon scale at the recombination epoch by intro-ducing the time-varying fundamental constant, extra radiation, or early dark energy (EDE) is a simple approach to this discrepancy (so-called the Hubble tension). We examine them with paying attention to the fit to BBN. We find that a smaller electron mass is preferred in BBN era because the greater electron mass leads to a larger helium mass fraction. We also find that a fit to BBN in EDE models also is somewhat poorer than that in the ΛCDM model, because the increased inferred baryon asymmetry leads to smaller deuterium abundance. Another important cosmological measurement is baryon acoustic oscilla-tion (BAO). The results of the latest BAO measurements by Dark Energy Spectroscopic Instrument (DESI) survey have been reported. We present constraints on the varying electron mass model and early dark energy mod-els in new DESI data as well as cosmic microwave background by Planck and the conventional BAO data from 6dF, MGS, and DR12 and supernovae light curve data into analysis. Since new DESI BAO data indicate a slightly longer sound horizon rdh than the other BAO observations, for the two models, we find a higher Hubble constant is indicated
