What is the biggest number? Is the universe infinite? How did the universe begin? Might every event repeat again and again and again and again… Is the Earth just one of uncountable copies, tumbling through an unending void? Your intuition is no use here. Faith alone can’t save you.
Mathematicians have discovered there are infinitely many infinities, each one infinitely bigger than the last. And if the universe goes on forever, the consequences are even more bizarre. In an infinite universe, there are infinitely many copies of the Earth and infinitely many copies of you. Older than time, bigger than the universe and stranger than fiction. This is the story of infinity.
In How Long is a Piece of String?, they enlist standup-comic-turned-physics-enthusiast Alan Davies in answering the seemingly simple question of the film’s title, only to find in it a lens — a very blurry lens — on the very fabric of reality. Along the way, Davies asks some of the world’s top scientists to measure his piece of string, gets repeatedly discombobulated by mathematician Marcus du Sautoy (he of The Number Mysteries fame), and turns to quantum mechanics to try to work out where the individual atoms and particles that make up the string actually are. The result is as enlightening as it is entertaining.
Your string does not actually possess a length. Somehow, by measuring it, we create a length for the string.
The matter of everybody in the world, the whole of the human race, amounts to a sugar cube. The rest is just space.
Reality, in some sense, does not exist unless we’re actually observing it. And it’s our act of observation that makes things real.
When Feynman faces a problem, he’s unusually good at going back to being like a child, ignoring what everyone else thinks… He was so unstuck — if something didn’t work, he’d look at it another way.” ~ Marvin Minsky, MIT
At around minute 39, Feynman gives a fantastic analogy-turned-explanation that captures what’s essentially the heart of the scientific process:
In the case of the chess game, the rules become more complicated as you go along, but in the physics, when you discover new things, it looks more simple. It appears, on the whole, to be more complicated because we learn about a greater experience — that is, we learn about more particles and new things — and so the laws look more complicated again. But if you realize all the time, what’s kind of wonderful is as we expand our experience into wilder and wilder regions of experience, every once in a while we have these integrations in which everything is pulled together in a unification, which turns out to be simpler than it looked before.”
Tender and intelligent, the film reveals some of Feynman’s defining qualities: his intense cross-disciplinary curiosity and determination (he taught himself to be a skillful artist, studying drawing like he studied science); his thoughtful, caring character (the anecdote Joan, Feynman’s younger sister, recounts at about 9:04 is just about the most poetic expression of nerd-affection I’ve ever encountered); and, perhaps above all, the remarkable blend of humility and genius that made him able to see error and wrongness as an essential piece of intellectual inquiry and truth itself.
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