GeoengineeringCert
plain-language theorem explainer
GeoengineeringCert packages the claim that exactly five geoengineering approaches exist, that the safe-deployment band is non-degenerate, and that the band contains the numerical point 0.118. Climate researchers working inside the Recognition Science framework cite the structure to certify that the five canonical methods satisfy the J-cost safe-deployment criterion derived from the phi-ladder. The declaration is a bare structure definition with three fields and no computational body.
Claim. A certificate consists of three assertions: the set of geoengineering approaches has cardinality 5, the lower bound of the safe band is strictly less than its upper bound, and the open interval contains the value 0.118.
background
The module introduces five canonical geoengineering approaches as an inductive type whose constructors are stratospheric aerosol injection, marine cloud brightening, ocean iron fertilisation, carbon dioxide removal, and cirrus cloud thinning; these correspond to configDim equal to 5. The safe band is fixed by the constants 0.11 and 0.13, which the module documentation identifies with the canonical J(φ) interval on the perturbation ratio. Upstream results supply the inductive type together with the two numerical bounds that define the safe-deployment threshold.
proof idea
The declaration is a structure definition that directly declares the three fields without invoking lemmas or tactics.
why it matters
The structure is instantiated by the downstream definition geoengineeringCert, which supplies the concrete witnesses geoengineeringApproach_count, safeBand_nondegenerate, and safeBand_contains_phi_point. It certifies that the five approaches lie inside the J(φ) safe band as stated in the module documentation. In the Recognition framework the construction links the configDim parameter to the climate application of the recognition composition law and the phi-ladder risk profiles.
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