Alphabeta Math
LemmaStatement: Literature-sourcedProof: AI-generatedPipeline-generatedprecheck passjudge pass (gpt-6-luna)verified 2026-11-04 (gpt-6.1-sol)
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

Higher Zhu action on the Omega spaces of an arbitrary weak module

Statement

Let V be a vertex operator algebra with finite-dimensional nonnegative integral state grades, allowing V0 larger than C1, and let M be any weak left V-module. For an integer N≥0 define ΩN(M)={w∈M: a(m)w=0 whenever a is homogeneous and m≥wt(a)+N}. For homogeneous a of weight r put o(a)=a(r−1), extending linearly in a. Every o(a) preserves ΩN(M), every element of ON(V) acts by zero, and o(a∗Nb)w=o(a)o(b)w,o(1)w=w. When V is of CFT type, the linked associative-quotient theorem consequently makes ΩN(M) a unital left AN(V)−module. The preservation, ON−annihilation and multiplicativity identities themselves hold in the full nonnegative scope just stated. No grading, local finiteness or semisimplicity of L(0) on M is assumed. This is the forward action; no converse rationality criterion is asserted.

Facts & Assumptions

Given: The full non-super conformal state-field setup and weak module in the Statement. Here the broader term “vertex operator algebra” means the following data, without the CFT-type condition V0=C1.

[F1]

V is a complex vector space with vacuum 1∈V0, translation T, and state-field map Y(a,z)=∑j∈Za(j)z−j−1 satisfying the lower-truncation, vacuum/creation, translation-covariance, and locality axioms of Vertex algebra in the state–field convention. It has a conformal vector ω∈V2 with Y(ω,z)=∑j∈ZL(j)z−j−2 and central charge c∈C, where [L(m),L(n)]=(m−n)L(m+n)+c12(m3−m)δm+n,0id⁡V for all m,n∈Z, and L(−1)=T. The operator L(0) is diagonalizable and V=⨁r≥0Vr, where Vr={a:L(0)a=ra} is finite dimensional. No condition V0=C1 is imposed. A weak left module M is a complex vector space with a lower-truncated field map YM(a,z)=∑m∈Za(m)Mz−m−1, vacuum action, and the full module Jacobi identity of Module for an ordinary vertex algebra; it has no grading or L(0)-semisimplicity assumption. For homogeneous a∈Vr, write wt(a)=r.

[F2]

Taking the two residues of the module Jacobi identity in [F1] gives, for all integers m,n, [a(m)M,b(n)M]=∑j≥0(mj)(a(j)b)(m+n−j)M,(a(m)b)(n)M=∑t≥0(−1)t(mt)(a(m−t)Mb(n+t)M−(−1)mb(m+n−t)Ma(t)M). The first sum is finite by state truncation; on each fixed vector the two terms of the iterate sum are separately finite by rightmost-mode truncation. For negative integer upper indices, (mt)=m(m−1)⋯(m−t+1)/t!. Translation covariance and the conformal-vector residues give (Ta)(m)M=−ma(m−1)M, [LM(0),a(m)M]=(r−m−1)a(m)M, and wt(a(j)b)=r+wt(b)−j−1 when the state product is nonzero. These are consequences of the stated Jacobi axioms; they do not require V0=C1.

[F3]

For homogeneous a∈Vr and b∈V, and each N≥0, the formulas used here are a∘Nb=∑j=0r+N(r+Nj)a(j−2N−2)b,a∗Nb=∑p=0N(−1)p(N+pN)∑j=0r+N(r+Nj)a(j−N−p−1)b, Da=(T+L(0))a=Ta+ra,ON(V)=span⁡C{a∘Nb,  Da:a,b∈V}, where the circle expression is extended linearly over homogeneous first inputs. This is the full nonnegative-grade convention used locally; in the CFT-type case it agrees with Higher Zhu quotients and candidate products, and Associative structure of the higher Zhu quotients separately proves associativity and descent of the quotient product.

Proof

1.1givenF2algebra

Let a have weight r and b have weight s. For m≥s+N, commuting bm past ar−1 gives terms (bja)m+r−1−j with coefficient binom(m,j). Their state weight is s+r-j-1 and their mode index is at least this weight plus N. Each kills w in ΩN(M), as does ar−1bm w. The commutator sum is finite by state truncation. Thus o(a) preserves ΩN(M). Vacuum acts identically by the module vacuum identity.

1.2F1F2algebra

The zero mode of a circle generator is ∑j=0r+N(r+Nj)(a(j−2N−2)b)(r+s+2N−j). Apply the iterate identity. In every first term the b index is r+s+2N−j+t≥s+N, so that term kills w. In the second terms the b index is the fixed r+s-2-t. Values t≥r+N kill w through at. For each remaining t<r+N, the summed coefficient is a scalar multiple of ∑j=0r+N(−1)j(r+Nj)(j−2N−2t)=0, the finite difference of order r+N of a polynomial in j of degree t. Thus every circle generator acts by zero. All sums can be exchanged here: j ranges over a finite set; in the first iterate sum br+s+2N−j+tw is zero for all large t, and in the second at w is zero for all large t. Also o(Ta+ra)=−rar−1+rar−1=0. Therefore o(ON(V))=0. This includes r+N=0, where the second surviving t range is empty.

2.1F1F2step 1.2algebra

Expand o(a∗Nb) using F1 and the iterate identity. For a fixed outer star index p, the second iterate terms again have b index r+s-2-t independent of j. They vanish for t≥r+N, and for t<r+N their sum over j is the finite difference of the degree-t polynomial binom(j-N-p-1,t), hence zero. In the first terms put the a index k=j−N−p−1−t. Its b index is r+s-2-k. The Omega cutoff on b eliminates k≤r−N−2. The inequalities j≤r+N and t≥0 give k≤r−1. Thus the only possible terms are a(r−1−a)b(s−1+a)w,0≤a≤N. Write l=r+N−j. Then t=a−p−l, so their coefficient is exactly Ca=∑p=0a(−1)p(N+pN)∑l=0a−p(r+Nl)(−1)a−p−l(r−p−l−1a−p−l). This expression accounts for every surviving first term; it uses no cancellation of unknown infinite sums.

3.1F1step 1.1step 1.2step 2.1algebra∎

The inner sum is the coefficient of xa−p in (1−x)r−p−1(1+x1−x)r+N=(1−x)−N−p−1. It therefore equals binom(N+a,a-p). Consequently Ca=∑p=0a(−1)p(N+pN)(N+aa−p)=(N+aa)∑p=0a(−1)p(ap)={1a=0,0a>0. Only o(a)o(b)w remains, proving multiplicativity. Step 1.1 and step 1.2 give the claimed full-scope identities. In the CFT-type case F1 then gives the claimed unital AN(V)−action. No existence/induction theorem or nonresonance of conformal-weight differences was used.

Depends on

Dependency tree · 2 levels

Sources