By way of example, consider the following quote from the Wikipedia article on Schrodinger:
Schrödinger's famous thought experiment poses the question, when does a quantum system stop existing as a mixture of states and become one or the other?
This is the same as saying:
Schrödinger's famous thought experiment poses the question, when does a quantum system stop existing as a one or the other and become one or the other?
If you don't believe these two statements are equivalent, follow the link which clarifys "mixture" and you will see that my substitute of "one or the other" for "mixture" is an entirely appropriate substitute.
Perhaps you disagree that my substitute has the same meaning as the concluding "one or the other" - but what does the concluding phrase mean if not what the former means?
There isn't any other meaning. Schrodinger's question - like Wikipedia's paraphrasing - is a completely silly question. No wonder nobody can answer it.
Wednesday, September 2, 2009
Semantics
Are the previous posts just a semantic argument?
Well it depends on what is meant by "semantic argument". The fundamental substance of any theory are the words (or their equivalent, eg. mathematical symbols) in which that theory is constructed. If not with words (or their equivalents, eg. pictures) then what theory would we be talking about? Or rather - not talking about - as the case would then be.
Answer that question silently if you think that will make any difference.
Well it depends on what is meant by "semantic argument". The fundamental substance of any theory are the words (or their equivalent, eg. mathematical symbols) in which that theory is constructed. If not with words (or their equivalents, eg. pictures) then what theory would we be talking about? Or rather - not talking about - as the case would then be.
Answer that question silently if you think that will make any difference.
Parallel Universe
The parallel universe model of quantum theory is based on Schrodinger's mis-interpretation of quantum theory. David Deutsch champions the same mis-interpretation.
Schrodinger uses the word "and" rather than "or" to describe his cat in the box (to describe his problem with quantum theory). He thinks of the cat as in some sense both alive and dead.
Confronted with this same artificial problem, subsequent thinkers have then tried to solve it by proposing a multiple universe theory, eg. in one universe the cat is alive and in another universe the cat is dead.
However the problem can also be solved by not constructing it in the first place. We can say there is one universe (or one part of the universe) in which the state of the cat is unknown - or more specifically: we can say the cat is alive or dead.
And in another part of the universe (eg. at a later time) the cat is then observed to be dead. Or (ie. quantum theoretically) the cat is then observed to be alive.
Schrodinger uses the word "and" rather than "or" to describe his cat in the box (to describe his problem with quantum theory). He thinks of the cat as in some sense both alive and dead.
Confronted with this same artificial problem, subsequent thinkers have then tried to solve it by proposing a multiple universe theory, eg. in one universe the cat is alive and in another universe the cat is dead.
However the problem can also be solved by not constructing it in the first place. We can say there is one universe (or one part of the universe) in which the state of the cat is unknown - or more specifically: we can say the cat is alive or dead.
And in another part of the universe (eg. at a later time) the cat is then observed to be dead. Or (ie. quantum theoretically) the cat is then observed to be alive.
Quantum Bits and Schrodinger
Quantum theory establishes some concepts that are apparently difficult to express in everyday language. One of the apparently difficult ones is the concept of Complimentarity.
Schrodinger once suggested that the complimentary aspect of quantum theory was absurd insofar as it implied that, prior to observation, a metaphorical cat (in a box) was both alive and dead at the same time.
However I think Schrodinger was wrong in this respect. It appears to me that quantum theory does not suggest the cat is both alive and dead at the same time. On the contrary, it appears to me that the theory is suggesting the cat is alive or dead (at the same time).
In other words - the theory speaks in exactly the same way in which we would normally speak about an unobserved cat.
The real problem is that we can't adequately describe the classical concept of an unobserved cat. How do we make a valid classical statement such as: the cat is dead before we know whether that statement is correct, ie. before we know whether the cat is dead. And even more distressingly - how do we make such a statement without our statement being just one example of two equally possible statements?
In other words how can we not make a quantum theoretcial statement? We can't. The quantum theoretical approach is actually the default method of articulation.
Quantum computation.
In classical computation a bit can be a one (1) or a zero (0) - but not at the same time. This is the limitation of classical computation. It is alien to the way in which we normally think and speak about the unknown state of things. It is this aspect of classical computation which is fundamentally flawed.
Unlike in classical computation, in quantum computation a bit (called a qbit) can be a one or zero at the same time. And it is this capacity of qbits to mirror the way in which we actually think and speak about the unknown state of things that makes quantum computation potentially very powerful.
Carl Looper
Schrodinger once suggested that the complimentary aspect of quantum theory was absurd insofar as it implied that, prior to observation, a metaphorical cat (in a box) was both alive and dead at the same time.
However I think Schrodinger was wrong in this respect. It appears to me that quantum theory does not suggest the cat is both alive and dead at the same time. On the contrary, it appears to me that the theory is suggesting the cat is alive or dead (at the same time).
In other words - the theory speaks in exactly the same way in which we would normally speak about an unobserved cat.
The real problem is that we can't adequately describe the classical concept of an unobserved cat. How do we make a valid classical statement such as: the cat is dead before we know whether that statement is correct, ie. before we know whether the cat is dead. And even more distressingly - how do we make such a statement without our statement being just one example of two equally possible statements?
In other words how can we not make a quantum theoretcial statement? We can't. The quantum theoretical approach is actually the default method of articulation.
Quantum computation.
In classical computation a bit can be a one (1) or a zero (0) - but not at the same time. This is the limitation of classical computation. It is alien to the way in which we normally think and speak about the unknown state of things. It is this aspect of classical computation which is fundamentally flawed.
Unlike in classical computation, in quantum computation a bit (called a qbit) can be a one or zero at the same time. And it is this capacity of qbits to mirror the way in which we actually think and speak about the unknown state of things that makes quantum computation potentially very powerful.
Carl Looper
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