Observing a Quantum Measurement
- URL: http://arxiv.org/abs/2105.00061v1
- Date: Fri, 30 Apr 2021 19:47:13 GMT
- Title: Observing a Quantum Measurement
- Authors: Jay Lawrence
- Abstract summary: We show that a superposition of both paths may be observed compatibly with properties attributed to state collapse.
Nondestructive measurements of a set of compatible joint observables can be performed.
A novel perspective is given as to why, within unitary quantum theory, ordinary measurements are blind to such superpositions.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: With the example of a Stern-Gerlach measurement on a spin-1/2 atom, we show
that a superposition of both paths may be observed compatibly with properties
attributed to state collapse - for example, the singleness (or mutual
exclusivity) of outcomes. This is done by inserting a quantum two-state system
(an ancilla) in each path, capable of responding to the passage of the atom,
and thus acting as a virtual detector. We then consider real measurements on
the compound system of atomic spin and two ancillae. Nondestructive
measurements of a set of compatible joint observables can be performed, one for
a superposition and others for collapse properties. A novel perspective is
given as to why, within unitary quantum theory, ordinary measurements are blind
to such superpositions. Implications for the theory of measurement are
discussed.
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