Tags » Mathematical Physics
Often, the study of the natural world reveals unexpected connections between seemingly disparate topics, and researchers can find themselves working in an area very far removed from their usual work. 825 more words
Quantities are not a human invention.
Early humans saw that things existed in various quantities, and named the various quantities.
When a single thing of a class of things – whether it’s pebbles, people, protons, pears or any other class of physical object – humans name that quantity ‘one’. 529 more words
We consider the causal structure of generalized uncharged McVittie spacetimes with increasing central mass $m (t)$ and positive Hubble factor $H (t)$. Under physically reasonable conditions, namely, a big bang singularity in the past, a positive cosmological constant and an upper limit to the central mass, we prove that the patch of the spacetime described by the cosmological time and areal radius coordinates is always geodesically incomplete, which implies the presence of event horizons in the spacetime. 67 more words