The struggle to find the origins of time - Astronomy Magazine

What is time? Why is it so different from space? And where did it come from? Scientists are still stumped by these questions — but working harder than ever to answer them.

This spin foam is a 3+1-dimensional structure, where the 1 represents the direction along which the changes between spin networks occur. What is remarkable about spin foams is that although they seem… [+4474 chars]

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