0.2: Physical Observables
- Page ID
- 20858
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Physical observables are represented by linear, hermitian operators that act on the vectors of the Hilbert space. If A is such an operator, and 
is an arbitrary vector in the Hilbert space, then A might act on to produce a vector 
, which we express as
Since is representable as a column vector, A is representable as a matrix with components
The condition that A must be hermitian means that
or
