The glue ledger at a cut the subset misses #
RS21's bookkeeping (14) compares the circuit count of the composed graph with the two fragments' counts and the number of components of the union of their matchings. In the flag model the composition is built one interface pair at a time, and each step moves those quantities together: the circuit count and the number of components of the union.
GlueChord carries that ledger across a glue whose edge the subset
uses. This file carries it across the glues the subset misses —
where the interface edge is not in the subset, and where a closed cut
is left out of it. There nothing moves at all: the used labels are
the same on both sides, the chord matching is unchanged, and so is
the circuit count.
The ledger reads only the matching #
Both quantities the ledger tracks — the circuit count and the chord matching's pairing — are read off the transition system's matching alone, so two systems that match alike carry the same ledger. That is what lets the ledger be stated in whichever direction a glue happens to construct its system.
The chord matching reads only the matching.
The cut matching's pairing reads only the matching.
The ledger reads only the matching.
An open glue whose edge the subset misses #
Neither glued label is used when the interface edge is out of the subset.
At a cut the subset misses, the second glued flag is not a boundary flag of the lift.
The chord matching is unchanged across a glue whose edge the subset misses: no chain reaches the cut, so no chain is rerouted.
The used labels are the same across a glue whose edge the subset misses.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The glued cut matching's pairing is the lifted one's across a glue whose edge the subset misses.
A glue whose edge the subset misses moves nothing. The circuit count and the number of components of the union are both unchanged.
One stage of the interface recursion at an open cut the subset misses.
A closed glue whose edge the subset leaves out #
At a closed cut the subset has a free choice: the closed-off edge is
in it or not. When it is not, the two glued labels are unused, the
chord matching simply transports, and the circuit count is
unchanged — so nothing moves here either. (When it is, one component
disappears; that is GlueChord's closed ledger.)
Neither glued label is used when the closed-off edge is left out of the subset.
The same at a closed cut the subset misses.
The used labels are the same across a closed glue whose edge the subset leaves out.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The glued cut matching's pairing is the lifted one's across a closed glue whose edge the subset leaves out.
A closed glue whose edge the subset leaves out moves nothing. The circuit count and the number of components of the union are both unchanged.
The closed glue, in the direction the recursion runs #
The interface recursion is given the fragment before the glue and
builds the one after it, so it wants its transition system built the
same way round. RelTransitionSystem.glueClosed does that, and the
ledger transports to it because the round trip leaves the matching
alone.
The ledger transports to the forward glue. Ungluing the forward glue returns a system matching like the original, so the two carry the same ledger.
A closed glue whose edge the subset carries drops one component, stated at the forward glue.
One stage of the interface recursion at a closed cut the subset carries, stated at the forward glue.
A closed glue whose edge the subset leaves out moves nothing, stated at the forward glue.
One stage of the interface recursion at a closed cut the subset leaves out, stated at the forward glue.