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We present the interesting coincidence of cosmology and astrophysics thatpoints toward a dimensionless age of the universe H_0*t_0 that is close to one.Despite cosmic deceleration for 9 Gyr and acceleration since then, we findH_0t*_0 = 0.96 +/- 0.01 for the LCDM model that fits SN Ia data fromPan-STARRS, CMB power spectra, and baryon acoustic oscillations. Similarly,astrophysical measures of stellar ages and the Hubble constant derived fromredshifts and distances point to H_0*t ~ 1.0 +/- 0.1$. The wide range ofpossible values for H_0*t_0 realized during comic evolution means that we liveat what appears to be a special time. This "synchronicity problem" is notprecisely the same as the usual Coincidence problem because there arecombinations of Omega_Matter and Omega_Lambda for which the usual coincidenceproblem holds but for which H_0*t_0 is not close to 1.

The dimensionless age of the Universe: a riddle for our time