Get Started Improving Your Philsci Archive Experience

…thing else? Enter your search keywords into Google, followed by this string: site:philsci-archive.pitt.edu This will return a Google search for your keywords, restricted to Philsci archive. Trust me, this is a real pain-reliever: for example, searching for “van fraassen” returns baloney on Philsci archive’s search engine, while Google returns hundreds of items. For more options, use Google’s advanced search to find what you want. Browse by Categor…

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Writing a book on time reversal

…the CPT theorem, their significance, and the extent to which CPT invariance may fail in future physical theories. Time reversal, antimatter, and the cosmos: The relationship between time reversal, CPT, and some puzzles of modern cosmology….

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New Directions in Foundations of Physics 2008

…with the help of Paul Teller’s now-legendary navigating abilities. As the talks got going, I couldn’t help but notice Charles Misner, another one of my physics-heros, sitting right next to me. The first talk, delivered by Laura Ruetsche, was the type of argument that only a philosopher of physics could give. Laura had drawn a very creative connection between the way in which we think about laws of nature, and the problem of unitarily inequivalent…

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Can Time Unfold in the Wrong Direction?

…f spatial regions. However, William and the astronaut will agree about the order in which time-like separated events occur: first Harold is crowned, and then Harold is slain. Figure 1: An observer on Earth and an astronaut traveling away with velocity c/2 will describe two different foliations of spacetime into space-like hypersurfaces of simultaneity. On the other hand, an accelerating observer will not generally agree about the order in which th…

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The physics of the 2015 Supertide in Western Europe

…New moon (sun and moon align — sometimes also causes eclipse) Stronger tide: New moon + Perigee (Perigean tide) Strongest tide: New moon + Perigee + Spring (Spring Perigean tide) The Supertide was just a Spring Perigean tide that occurred the day before the equinox. That is the main reason that it was so strong. It is also possible that it was augmented by the effects of global wind. In summary: the supertide in Western Europe was caused by the Ne…

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