query: Explanation: $H^{-1}$ is the time-scale over which the universe changes by $\mathcal{O}(1)$
positive_passages.docid: 62168
positive_passages.text: Hubble time, the age of the Universe and expansion rate
negative_passages.docid: 154529
negative_passages.text: Redshift and conformal time
negative_passages.docid: 72416
negative_passages.text: The universe appears to have a lower bound in the time dimension, why not an upper bound?
negative_passages.docid: 112452
negative_passages.text: Why does dark energy produce positive space-time curvature?
negative_passages.docid: 42584
negative_passages.text: Curved space-time VS change of coordinates in Minkowski space
negative_passages.docid: 40338
negative_passages.text: Ordinary Differential Equations used in Cosmology
negative_passages.docid: 140576
negative_passages.text: Time reversal symmetry and T^2 = -1
negative_passages.docid: 9463
negative_passages.text: What is the proof that the universal constants ($G$, $\hbar$, $\ldots$) are really constant in time and space?
negative_passages.docid: 138729
negative_passages.text: What happens when $\lvert\omega\rvert =1$?
negative_passages.docid: 141447
negative_passages.text: Inverse Square Law and extra space dimensions
negative_passages.docid: 53952
negative_passages.text: What does $\frac{1}{\sqrt{1 - \frac{v^2}{c^2}}}$ mean with respect to special relativity?
negative_passages.docid: 131519
negative_passages.text: intuition on the fundamental group of $S^1$
negative_passages.docid: 76853
negative_passages.text: Interpretation of $\mathbf{y}^T(\mathbf{I}-\mathbf{H})\mathbf{y}$ in OLS
negative_passages.docid: 92427
negative_passages.text: Geodesic equation from the proper time integral
negative_passages.docid: 35298
negative_passages.text: A question about the higher-order Weyl variation for the geodesic distance
negative_passages.docid: 69667
negative_passages.text: What is the equation for the scale factor of the universe, a(t), for the best fit of data to the $\Lambda CDM$ Model of Cosmology?
negative_passages.docid: 56592
negative_passages.text: The Sobolev Space $H^{1/2}$