lin-0281

Local-to-global, causal, and decision notation

Notation

Meaning

Role in lincs

\(\mathcal F(U)\)

sections over context \(U\)

Local predictions, arguments, evidence, or model fragments.

\(\rho ^U_V\)

restriction map

Transports a section on \(U\) to \(V\subseteq U\).

\(\check C^\bullet (\mathcal U,\mathcal F)\)

Cech complex of a cover

Records overlap compatibility and higher gluing information.

\(\delta _{\check C}\)

Cech coboundary

Measures failure of local data to agree on overlaps.

\(\operatorname {colim}\), \(\lim \)

colimit and limit

Universal aggregation and compatibility constructions.

\(P(Y\mid X=x)\)

observational conditional

Evidence obtained by conditioning, without an intervention claim.

\(P(Y\mid \operatorname {do}(X=x))\)

interventional distribution

A measure defined under a declared intervention mechanism.

\(D_{\mathrm{KL}}(P\Vert Q)\)

Kullback–Leibler divergence

Compares identified measures but does not certify causal identification.

\(V^\pi ,Q^\pi \)

value functions

Decision quantities under policy \(\pi \).

\(T^\pi \), \(T^\ast \)

Bellman operators

Policy and optimality factorizations used in decision and RL chapters.

\(\operatorname {Ran}_J(J^\ast \operatorname {Lan}_J F)\)

universal decision composite

Extension followed by consistency relative to the information made visible by \(J\).

Boundary Boundary: Typed notation

A symbol does not acquire causal, decision, or repair semantics from its shape alone. Its type, declaration, observer, and admission contract determine what the notation licenses in a particular application.