State
History state
The solution at every recorded time step, superposed in one register with a clock. Reading one time out of it costs a measurement that lands on the others too.
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
Anything that asks for one of these will accept this, because it is narrower. The reverse does not hold.
- State you can prepare
Not the state itself but the routine that makes it — which is the useful form, because a routine can be run again, controlled, and inverted, and a state that has already collapsed can do none of those.
- Answer about the solution
Whatever a route hands back about the state of the system at the end — a state you can measure, a history over the whole interval, or a single number. Which of the three you get is a real difference between routes, so each is its own kind below this one.
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
No recorded process returns this. Either it is where a reader starts — a problem, a matrix, a machine — or it is an object this graph names and no route yet reaches.
Work that starts here
No process asks for this by name. The ones below ask for something broader, and this is a kind of it — so they take it as it stands.
Also accepted where something broader is wanted
These ask for an object this one is a kind of. Narrowing composes in that direction and only that direction: handing on something broader than a process asks for would be a skipped conversion.
- Estimate an observable
Given the ability to prepare and a description of an observable , return a classical scalar within of at confidence . The state is never returned; only the number is.