Henri Bergson was one of the most celebrated philosophers of the early 20th century, and his very public conflict with Albert Einstein over "the nature of time" was considered the reason that Einstein's 1921 Nobel Prize was NOT awarded specifically for his Theory of Relativity. Ouch.
Why Time Flies: A visualization by Maximilian Kiener of philosopher Paul Janet's theory of why time seems to pass more quickly as one gets older. As Wonkblog explains it, The apparent length of a period of time is proportional to our life span itself.
In a Multiverse, What Are the Odds? "Testing the multiverse hypothesis requires measuring whether our universe is statistically typical among the infinite variety of universes. But infinity does a number on statistics." (previously) [more inside]
It took me nine minutes to notice that the shape of the boy’s ear precisely echoes that of the ruff along the squirrel’s belly—and that Copley was making some kind of connection between the animal and the human body and the sensory capacities of each. It was 21 minutes before I registered the fact that the fingers holding the chain exactly span the diameter of the water glass beneath them. It took a good 45 minutes before I realized that the seemingly random folds and wrinkles in the background curtain are actually perfect copies of the shapes of the boy’s ear and eye, as if Copley had imagined those sensory organs distributing or imprinting themselves on the surface behind him. And so on. What this exercise shows students is that just because you have looked at something doesn’t mean that you have seen it.
The Nature of Computation - Intellects Vast and Warm and Sympathetic: "I hand you a network or graph, and ask whether there is a path through the network that crosses each edge exactly once, returning to its starting point. (That is, I ask whether there is a 'Eulerian' cycle.) Then I hand you another network, and ask whether there is a path which visits each node exactly once. (That is, I ask whether there is a 'Hamiltonian' cycle.) How hard is it to answer me?" (via) [more inside]
"It doubtless seems highly paradoxical to assert that Time is unreal, and that all statements which involve its reality are erroneous. ... I believe that time is unreal. But I do so for reasons which are not, I think, employed by any of the philosophers whom I have mentioned, and I propose to explain my reasons in this paper." ~McTaggart, The Unreality of Time, 1908. (Bonus: The Kant Song.)
The cable clock. This clocks tells time, just like any other clock, but the movement of the hands is hypnotic and beautiful. To physicists, time is defined by quantum mechanics. A photon with energy h (Planck's constant) behaves as though it were oscillating once per second. For Philosphers, time is less concrete, and they love to talk about it. Western society lives by the clock - does it make a difference if this is the kind of clock that you live by? After all, everyone knows that time is money. If you have to be a clock watcher, does it help if the clock is as calming as the Cable Clock is?
Timehunt. Time, philosophy, alchemy, tons of interactive puzzles and great flash. I can't tell you more, I'm still figuring it out.