Map of the Cosmic Acceleration Literature
Ten years ago, the physics community came to agree that the expansion of the Universe is experiencing a positive acceleration. The experts still disagree on why. Everything but the kitchen…
Read moreRotating Discs in GR: Part I
Introduction. Craig Callender (2001) and Jeremy Butterfield (2004) have recently suggested that the Rotating Disc Argument (RDA) fails in General Relativity. I argue that this conclusion is wrong: two recharged…
Read moreGet Started Learning General Relativity Online
General Relativity is the theory of gravitation introduced by Einstein in 1915, and developed throughout the 20th century. And you’ve decided you want to learn it. But why spend hundreds…
Read moreVisualize a Black Hole at the Event Horizon
This cute little animation shows the causal structure around a classical black hole in an interesting way. The perspective is that of a body orbiting just outside the event horizon:…
Read moreSolving the Black Hole Information "Paradox"
In January, Abhay Ashtekar posted a short preprint in which he (along with two collaborators) proposed a new solution to the so-called black hole information paradox in 1+1 dimensions. Their…
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