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CITY SPINE · CANONICAL LINCHPIN
Kartekeya is the City’s operator-skeleton for turning a declared spectral law into an invariant citizen, a lawful projector, a reproducible contraction, and a routed civic record.
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The City contains many districts, dialects, proofs, simulations, archives, and application routes. Kartekeya is the common operation that lets them remain one City rather than a stack of unrelated exhibits:
$K\longrightarrow\ker K\longrightarrow P\longrightarrow H:=I-P\longrightarrow x_\infty=Px_0.$
It answers five questions every borough must answer:
That chain is the City’s vertebral column. Foundations supplies the operator. Representation Theory identifies the spectrum. Spectral Theory isolates the kernel. Python reconstructs it. Verification certifies it. Correction Borough preserves failed variants. The Monorail transports the manifest. The Citadel broadcasts the certified state. The Observatory receives everything not yet closed.
Let $K:\mathcal H\to\mathcal H$ be a linear operator and define
$E:=\ker K,\qquad P:=P_E,\qquad H:=I-P.$