We all experience the passage of time. This is not an illusion. We agree on the serial delivery of moments, and it is very hard to dislocate us from this…
Read moreGet Started Playing Ehrenfeucht-Fraisse Games
Ehrenfeucht-Fraisse games are a very useful method in logic, when you’re trying to figure out if two models are elementarily (logically) equivalent or not. This may be of special interest…
Read moreAnother Unexpectedly Simple Failure of Determinism
Here’s a simple Newtonian system that fails to determine a unique Cauchy evolution, in the spirit of Norton’s dome. In the system I will describe, one begins with a mass…
Read moreWhy does matter follow geodesics?
In the very first lessons on General Relativity, we learn that free particles follow geodesics — the equivalent of straight lines in curved spacetimes. Why? Well, it’s easy to show…
Read morePossible Positions on the Passage of Time
Presentism The present exists; the past and the future do not. Block The past, present and future all exist. Growing Block The past and present exist; the future is coming…
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