25 lines
764 B
Markdown
25 lines
764 B
Markdown
A Partial observation is, as the name implies, only an observation of a partial aspect of the result.
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First, we need to distinguish between alternatives we want to look at.
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Each alternative is a set A of deterministic possibilities.
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Partial observation yields for each alternative A the probability that the system is in a state in A.
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![[Pasted image 20260729122658.png]]
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We will often use this, less precise, definition however:
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![[Pasted image 20260729122833.png]]
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A partial observation of a classical probabilistic system does not change it.
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An example for this:
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![[Pasted image 20260729122952.png]]
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![[Pasted image 20260729123015.png]]
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## Partially measuring a quantum system
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![[Pasted image 20260729123551.png]]
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![[Pasted image 20260729123600.png]]
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