3 ms·

It's like you and a friend have a deck of cards. You each take a card from the deck, and then travel a million miles away. Then, at the crack of noon (synchro

It's like you and a friend have a deck of cards. You each take a card from the deck, and then travel a million miles away. Then, at the crack of noon (synchronized to GST, of course), you both look at your cards. Your card is the 3 of Clubs. You travel back to meet your friend, and discover that his card (which he measured at noon, just like you) was the 7 of Diamonds. You repeat this experiment a gazillion times and are amazed!! No matter how many times you run it, you and your friend never get the same card!!! It's as if the cards are sending spooky signals to each other! And after you double check that you and your friend are both looking only at 1200 GST, you realize that this spooky signal travels faster than the speed of light (since the it takes no time to "travel" a million miles). It's like magic, eh? Not really. The fact there is one of each card means it's impossible for you and your friend to have the same card. No magical spooky signals are being sent. (The real question is whether the quantum mechanical case is analogous to this contrived example. I think it is. The important difference in quantum mechanics it that you really don't know what card you have until you look at it. However, that doesn't mean that your card is sending a faster-than-light spooky signal to tell the other card what to be. And you certainly can't use it for signalling or anything useful.)

Filligree 14y ago
What you're describing is a hidden-variable theory, which has been ruled out by Bell's Theorem. Sorry.
- tedsanders 14y ago
  No need to be sorry. :) The point of my post is to convey the sense that this article headline has when it says that "spooky action" has a speed. Then, in the last paragraph, I ask whether the example I gave is actually analogous to quantum mechanics. I think it is, particularly if you see things through the many-worlds interpretation. In the many-worlds interpretation, you and your card exist in a superposition of 52 states, 1 for each possible card. When you look at your card, your wavefunction separates into 52 different experiences and that effect propagates out into the universe at a speed less than the speed of light. Nonetheless, when you compare your results with your friend, you find that you never got the same card, even though you looked at the same time. Nitpick: Bell's Theorem doesn't rule out hidden variable theories. Only local hidden variable theories.

Filligree 14y ago

What you're describing is a hidden-variable theory, which has been ruled out by Bell's Theorem. Sorry.

tedsanders 14y ago
No need to be sorry. :) The point of my post is to convey the sense that this article headline has when it says that "spooky action" has a speed. Then, in the last paragraph, I ask whether the example I gave is actually analogous to quantum mechanics. I think it is, particularly if you see things through the many-worlds interpretation. In the many-worlds interpretation, you and your card exist in a superposition of 52 states, 1 for each possible card. When you look at your card, your wavefunction separates into 52 different experiences and that effect propagates out into the universe at a speed less than the speed of light. Nonetheless, when you compare your results with your friend, you find that you never got the same card, even though you looked at the same time. Nitpick: Bell's Theorem doesn't rule out hidden variable theories. Only local hidden variable theories.