Re: Quantum Computers

Bryan Moss (
Thu, 19 Aug 1999 20:29:36 +0100

John K Clark wrote:

> >Did I mention hidden variables? I guess 'limited knowledge' implies
> >hidden variables, but it doesn't have to, no sir.
> Your distinction between hidden variables and limited knowledge eludes me.

The many-worlds FAQ states that within the Copehagen interpretation,

"...the view has generally been adopted that the wavefunction associated with an object is not a real "thing", but merely represents our *knowledge* of the object."

It then objects to this view,

"This stance means that we can't answer questions about what's actually happening, all we can answer is what will be the probability of a particular result if we perform a measurement. This makes a lot of people very unhappy since it provides no model for the object."

Hidden variables and many-worlds both share the idea that there's something else to the theory that can be said to be "actually happening" and that the fact that our only answer is a probability "makes a lot of people very unhappy". Why are they unhappy? Because they believe that a probability provides "no model for the object". My interpretation would be that the probability is no less real than any other explanation.