many-worlds fail

Originally posted by humy
But not confirmed with specifically having true randomness as opposed to only pseudo-randomness thus it still might be deterministic. Neither possibility (true randomness exists verses only pseudo-randomness exists) has yet validly been confirmed or refuted nor even shown to be very slightly more or less probable or improbable than the other.

What do you suppose would count as evidence of "true" probabilistic behavior? (I don't like the term "randomness" here - there is a crucial difference between those terms.)

Third time I've asked. Have you not seen it, or is the question bothersome?

Originally posted by apathist
Modern science has discovered, however, that quantum events are fundamentally indeterminate, or probabilistic.

Actually I don't think it has.

Originally posted by apathist
A person who says he cannot distinguish himself from others is either lying, insane, or perhaps a p-zombie.

And you are just a person who refuses to listen to explanations.

Tell me, if someone is in a room, then a moment later there is you and another person exactly like you, how do you know which of you is the real you and which is the copy?

In MWI there are no 'real' and 'copy' pairs. The original splits into two.

Originally posted by twhitehead
..
Tell me, if someone is in a room, then a moment later there is you and another person exactly like you, how do you know which of you is the real you and which is the copy?

The problem has not been to distinguish whether you are the original or the copy. The problem has been to determine which universe you are in.

If I'm in a room all alone, I may be a copy but I can still distinguish which person in that room is me!

One way to distinguish yourself from others is to notice you have (or are) a body. We are biological organisms, aren't we, with spatial location?

Stab all the bodies in the room with a knife. You'll recognize which body is yours when you feel a stabbing pain.

Originally posted by twhitehead...
In MWI there are no 'real' and 'copy' pairs. The original splits into two.[/b]

The original splits in two, yes.

And we are in one but not the other. See my post today to DeepThought. Your objection isn't working.

Originally posted by apathist
The original splits in two, yes.

And we are in one but not the other. See my post today to DeepThought. Your objection isn't working.

Is this many worlds deal just supposition to try to explain quantum physics?

Originally posted by twhitehead
And you are just a person who refuses to listen to explanations.

Tell me, if someone is in a room, then a moment later there is you and another person exactly like you, how do you know which of you is the real you and which is the copy?

In MWI there are no 'real' and 'copy' pairs. The original splits into two.

The answer to your question can be found in your question.... the 'real' you is the you who is cognizant of seeing the other 'you'.

Originally posted by apathist
The problem has not been to distinguish whether you are the original or the copy. The problem has been to determine which universe you are in.

If I'm in a room all alone, I may be a copy but I can still distinguish which person in that room is me!

One way to distinguish yourself from others is to notice you have (or are) a body. We are biological org ...[text shortened]... es in the room with a knife. You'll recognize which body is yours when you feel a stabbing pain.

I was going to say start pinching the 'other' you's until one of them says "Ouch", but there's always the risk that one them might be the real one... and you are not....

... ?

Originally posted by sonhouse
Is this many worlds deal just supposition to try to explain quantum physics?

That's a very real possibility. I don't think many people took the idea of other dimensions seriously until string theory came along... but today you can hear people talking about it as though it's an established fact.

Originally posted by lemon lime
The answer to your question can be found in your question.... the 'real' you is the you who is cognizant of seeing the other 'you'.

But the other you is also cognizant of seeing you.

Originally posted by apathist
The original splits in two, yes.

And we are in one but not the other.

I get that. But you seem to be under the impression that the one you are in, is in the same universe as the original and the other is not. This is not the case.

Originally posted by twhitehead
But the other you is also cognizant of seeing you.

Possibly, but I don't actually know that since I'm the only 'you' who I can be sure is cognizant of his own cognizance. But if you are correct, then the same would also be true of the one I'm observing.

If I look at a mirror I'm cognizant of my reflection. But how can I be sure I'm not the reflection and that what I'm seeing is not the 'real' me?

Originally posted by sonhouse
Is this many worlds deal just supposition to try to explain quantum physics?

Originally posted by apathist
The MWI fails to provide a deterministic resolution for the indeterminate quantum event.

Hence the word interpretation in the phrase Many Worlds Interpretation. The difficulty isn't what apathist is on about which misses the point - the purpose is to explain quantum mechanics in a way that makes sense not "to save determinism in physics". The problem with the Copenhagen Interpretation is that it simply does not explain why the wavefunction collapses, the Many Worlds Interpretation does and is complete in that sense. The problem with apathist's argument is that he's criticising it for succeeding in what it's setting out to do.

In the Many Worlds Interpretation determinism is preserved for an observer outside the universe - in other words there's a "God's eye view" from which it is deterministic and just an ensemble of universes evolving as one would expect by applying the Schrodinger equation. For an actual observer the outcome is not deterministic. An observer inside the universe is part of it so when the universe splits they do too, the indeterminism in physics is then due to the way we can only observe the parts of the global wavefunction that are coherent with our knowledge. So if we were to do the Schrodinger's cat experiment our measurement tells us that we are in the copy of the universe where the cat is alive, copies of us are in the dead cat universe but we no longer have access to them. I think up to here the concept works well. It succeeds in providing an account which explains the apparent indeterminism in physics in terms of partitioning of the wavefunction.

However, there's a problem. In something like the EPR experiment the two states are equally likely. So, we have the universe splitting into two equal parts. But, as is the case in most real world scenarios, what if the two or more outcomes are not equally likely? The account then has to provide an explanation as to why a universe has a weighting associated with it. I think that this is the real gap in MWI.

Originally posted by lemon lime
If I look at a mirror I'm cognizant of my reflection. But how can I be sure I'm not the reflection and that what I'm seeing is not the 'real' me?

There are relatively easy tests to tell whether or not your reflection is a concious entity. In the MWI, the other you would be a concious entity identical to you in every way except for one electron in one cell somewhere in your body.

Originally posted by DeepThought
Hence the word interpretation in the phrase Many Worlds Interpretation. The difficulty isn't what apathist is on about which misses the point - the purpose is to explain quantum mechanics in a way that makes sense not "to save determinism in physics". The problem with the Copenhagen Interpretation is that it simply does not explain why the wavefunction ...[text shortened]... to why a universe has a weighting associated with it. I think that this is the real gap in MWI.

It just seems to messy to have universes split up like that for every wave function collapse. I think the true situation will involve something we don't know about at this time. Maybe the universe is composed of foam where each bubble is a separate universe but I don't think that is what is really happening.

Some genius will sort this out if it takes a thousand years.