Add Up Every Number From One To Infinity, And You Get...
Obviously, if you stop this series at any point before infinity, it will produce a very large number. But if you use certain methods of summation that can apply to divergent series, you will get a non-infinite answer of -1/12. Laboratory testing has proved this conclusion, and physicists all over the world have come across the result in string theory equations.
Key Facts In This Video
The result of the infinite sum (1 + 2 + 3 + 4...) is used in string theory. (0:37)
The result of the infinite sum (1 - 1 + 1 - 1 + 1...) is 1/2. (1:54)
It's hard to conceive of an intuitive reason for why the infinite sum (1 + 2 + 3 + 4...) produces its strange result without writing out the proof. (6:38)