Posted: Jun 12, 2011 12:37 am
Paul Almond wrote:Teuton wrote:
Functions are abstract mathematical entities, so the quantum wave function cannot be the basis of physical reality, which must itself be a concrete physical entity (a quantum field?). It can at most represent that basis mathematically.
That sounds like a semantics issue to me, really …
No, that's a relevant ontological issue—really!
Paul Almond wrote:…- about whether we can use the word "function" or whether we are being lazy with semantics and ontology: what is being claimed by MWI is that "something" exists and that the "something" is described by the quantum wave function, and that that "something" can explain both quantum mechanics and the appearance of separate events to us.
You may say that the QWF describes, models, represents the physical basis of physical reality; but my point is that it is different from that basis, belonging to another ontological category. (Being a mathematical fictionalist, I don't believe in the real existence of abstract mathematical entities such as functions anyway.)
Paul Almond wrote:
The term "quantum wave function" is used by both advocates and detractors of MWI without too much issue - and I think they all understand what they mean.
I'm not so sure. Sometimes, physicists mix up concrete physical reality and abstract mathematical "reality".