State
A marked item, with its query bill
One candidate the check accepts, together with the number of queries it took and the probability the answer is right — or, at a stated confidence, the report that the domain holds none. What is uncertain differs between the routes that arrive here, and the object carries which: Grover samples at the end and is right with probability greater than a half, while the wildcard recovery ends every stage on an oracle answer confirming its guess, so there the bill is the random quantity and the answer is not.
A state is an object you can be holding, named once so that two routes reaching the same thing are drawn as reaching the same thing. It says nothing about how you got here or where you can go next — that is entirely in the processes below.
This is a kind of
This state is not recorded as a kind of anything else. It stands on its own in the vocabulary.
Narrower kinds of this
No state in the vocabulary is recorded as a narrower kind of this one.
Records that are this object
Nothing in the catalogue has been joined to this state. That is a gap in the join rather than a claim that no such object exists; the shelf on /repository lists what is joined and what is not, with the reason.
Work that arrives here
- Find the item a check accepts
Given a way to test candidates and nothing else — no order on the domain, no structure to exploit — return one candidate the test accepts, in fewer queries than looking at them all.
- Search by state discrimination
When one query can test a partial guess rather than a whole candidate, the answer is recovered by discriminating quantum states instead of by rotating amplitude. One query turns knowledge of positions into knowledge of of them, and the measurement that does it is the one that minimises the error — though a stage costs more than that one query, because the guess it produces has to be checked and repaired.
- Walk a graph to the vertex you want
When candidates sit on a graph and the work done at one vertex is still worth something at its neighbour, walk the graph instead of sampling it — and pay per move rather than per candidate.
Work that starts here
No recorded process takes this as its input. Nothing in this graph leaves from here.