V19·Act IV · Quantum

The context web

Contexts as nodes on a sphere of possible questions, with incompatible ones visibly unable to be answered at once.

The relation on screen

[A^, B^] \neq = 0 \Rightarrow no joint record

Incompatible reads have no common refinement, which is Kochen-Specker obstruction as a property of the record set.

Symbols

$A^, B^$: two measurement contexts
$[\cdot, \cdot]$: failure of joint refinability

loading contexts

what to look for · Contexts overlap pairwise but do not close into a global assignment.

Consensus to physics

01eight measurement contexts are defined on the same record carrier
02some share an effect and commute, others do not
03a single global assignment of outcomes to all contexts does not exist
04outcomes are therefore relative to the context that was measured, and carry no value before it

In standard physics

Kochen-Specker contextuality, the Bloch sphere

What separates the model from a hidden-variable account: the record does not carry an answer to every question in advance, only to the question actually asked.

boundary · Not a full Kochen-Specker no-go proof on this carrier. It is the context web the committed operation defines, and the phase operation within it is declared.

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