Reversibility and the Laws of Physics

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Time Reversal in Particle Physics
Explore advances in physics since Newton's time that reveal exceptions to the rule that interactions between moving particles are fully reversible. Could irreversible reactions between elementary particles explain the arrow of time? Weigh the evidence for and against this view.
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Can physics shed light on human aspects of the arrow of time such as memory, cause and effect, and free will? Learn that everyday features of experience that you take for granted trace back to the low entropy state of the universe at the big bang, 13.7 billion years ago.
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Consider Newton's laws in cases of two and three dimensions. For example, how fast does a rollercoaster have to travel at the top of a loop to keep passengers from falling out? Is there a force pushing passengers up as the coaster reaches the top of its arc? The answer…
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Symmetries don't only apply to geometrical objects. They apply to the laws of physics themselves. In this lecture, you may feel your mind twist in asymmetrical ways as you explore how symmetry governs the known forces of nature and how it helped form a wild theory that an as-yet-undiscovered particle--the…