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Entanglement of Socks

Entanglement of Socks

We're sitting at a table. On the table are two brown paper bags, a black sock and a white sock.

We both close our eyes, grab a sock, put it in a paper bag and close the bag.

Then we open our eyes. Neither one of us has any idea which sock is in our bag.

Then you say to me..

"Tell me exactly which sock is in my bag but without opening the bag."

My first reaction is that's impossible. So I say the content of your bag is a supposition of a black and white sock. Which is just a fancy way of saying I have no clue.

But then it occurs to me..

I can find out what's in your bag by opening my bag.

I open my bag, find a white sock, and tell you your bag contains a black sock.

No observation of any kind has been made on your bag. It's still sitting on the table unopened. But now we both know the content.

What is this saying about the nature of information?

Content written and posted by Ken Abbott