Nuprl Lemma : face_lattice-1-join-irreducible

I:fset(ℕ). ∀x,y:Point(face_lattice(I)).
  (x ∨ 1 ∈ Point(face_lattice(I)) ⇐⇒ (x 1 ∈ Point(face_lattice(I))) ∨ (y 1 ∈ Point(face_lattice(I))))


Proof




Definitions occuring in Statement :  face_lattice: face_lattice(I) lattice-1: 1 lattice-join: a ∨ b lattice-point: Point(l) fset: fset(T) nat: all: x:A. B[x] iff: ⇐⇒ Q or: P ∨ Q equal: t ∈ T
Definitions unfolded in proof :  all: x:A. B[x] face_lattice: face_lattice(I) iff: ⇐⇒ Q and: P ∧ Q implies:  Q member: t ∈ T prop: uall: [x:A]. B[x] subtype_rel: A ⊆B bdd-distributive-lattice: BoundedDistributiveLattice so_lambda: λ2x.t[x] so_apply: x[s] uimplies: supposing a rev_implies:  Q or: P ∨ Q
Lemmas referenced :  or_wf equal_wf lattice-point_wf face-lattice_wf names_wf names-deq_wf subtype_rel_set bounded-lattice-structure_wf lattice-structure_wf lattice-axioms_wf bounded-lattice-structure-subtype bounded-lattice-axioms_wf uall_wf lattice-meet_wf lattice-join_wf lattice-1_wf bdd-distributive-lattice_wf face-lattice-1-join-irreducible iff_wf face_lattice_wf fset_wf nat_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation sqequalHypSubstitution cut independent_pairFormation hypothesis introduction extract_by_obid isectElimination thin hypothesisEquality because_Cache applyEquality sqequalRule instantiate lambdaEquality productEquality cumulativity universeEquality independent_isectElimination setElimination rename addLevel productElimination impliesFunctionality dependent_functionElimination independent_functionElimination

Latex:
\mforall{}I:fset(\mBbbN{}).  \mforall{}x,y:Point(face\_lattice(I)).    (x  \mvee{}  y  =  1  \mLeftarrow{}{}\mRightarrow{}  (x  =  1)  \mvee{}  (y  =  1))



Date html generated: 2017_10_05-AM-01_10_05
Last ObjectModification: 2017_07_28-AM-09_29_41

Theory : cubical!type!theory


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