Definition .

Let φ 𝜑 \varphi italic_φ be as above. We say that φ 𝜑 \varphi italic_φ is a limiting Carleman weight (for the Laplacian) if

{ a , b } = 0 when a = b = 0 . formulae-sequence 𝑎 𝑏 0 when 𝑎 𝑏 0 \{a,b\}=0\quad\text{when }a=b=0. { italic_a , italic_b } = 0 when italic_a = italic_b = 0 . (24)

Definition 2

Two crossed modules μ : 𝔪 𝔫 normal-: 𝜇 normal-→ 𝔪 𝔫 \mu:{\mathfrak{m}}\to{\mathfrak{n}} italic_μ : fraktur_m → fraktur_n (with action η 𝜂 \eta italic_η ) and μ : 𝔪 𝔫 normal-: superscript 𝜇 normal-′ normal-→ superscript 𝔪 normal-′ superscript 𝔫 normal-′ \mu^{\prime}:{\mathfrak{m}}^{\prime}\to{\mathfrak{n}}^{\prime} italic_μ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT : fraktur_m start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT → fraktur_n start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT (with action η superscript 𝜂 normal-′ \eta^{\prime} italic_η start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) such that k e r ( μ ) = k e r ( μ ) = : V fragments k e r fragments normal-( μ normal-) k e r fragments normal-( superscript 𝜇 normal-′ normal-) normal-: V ker(\mu)\,=\,ker(\mu^{\prime})=:V italic_k italic_e italic_r ( italic_μ ) = italic_k italic_e italic_r ( italic_μ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) = : italic_V and c o k e r ( μ ) = c o k e r ( μ ) = : 𝔤 fragments c o k e r fragments normal-( μ normal-) c o k e r fragments normal-( superscript 𝜇 normal-′ normal-) normal-: g coker(\mu)\,=\,coker(\mu^{\prime})=:{\mathfrak{g}} italic_c italic_o italic_k italic_e italic_r ( italic_μ ) = italic_c italic_o italic_k italic_e italic_r ( italic_μ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) = : fraktur_g are called elementary equivalent if there are morphisms of Lie algebras ϕ : 𝔪 𝔪 normal-: italic-ϕ normal-→ 𝔪 superscript 𝔪 normal-′ \phi:{\mathfrak{m}}\to{\mathfrak{m}}^{\prime} italic_ϕ : fraktur_m → fraktur_m start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT and ψ : 𝔫 𝔫 normal-: 𝜓 normal-→ 𝔫 superscript 𝔫 normal-′ \psi:{\mathfrak{n}}\to{\mathfrak{n}}^{\prime} italic_ψ : fraktur_n → fraktur_n start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT such that they are compatible with the actions, meaning:

ϕ ( η ( n ) m ) = η ( ψ ( n ) ) ϕ ( m ) n 𝔫 m 𝔪 , formulae-sequence italic-ϕ 𝜂 𝑛 𝑚 superscript 𝜂 𝜓 𝑛 italic-ϕ 𝑚 for-all 𝑛 𝔫 for-all 𝑚 𝔪 \phi(\eta(n)\cdot m)\,=\,\eta^{\prime}(\psi(n))\cdot\phi(m)\,\,\,\,\,\,\,% \forall n\in{\mathfrak{n}}\,\,\,\forall m\in{\mathfrak{m}}, italic_ϕ ( italic_η ( italic_n ) ⋅ italic_m ) = italic_η start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_ψ ( italic_n ) ) ⋅ italic_ϕ ( italic_m ) ∀ italic_n ∈ fraktur_n ∀ italic_m ∈ fraktur_m ,

and such that the following diagram is commutative:


Definition 24 .

Let W 𝑊 W italic_W be any integer and let ( t , d ) ( / W ) 2 𝑡 𝑑 superscript 𝑊 2 (t,d)\in(\mathbb{Z}/W\mathbb{Z})^{2} ( italic_t , italic_d ) ∈ ( blackboard_Z / italic_W blackboard_Z ) start_POSTSUPERSCRIPT 2 end_POSTSUPERSCRIPT be any pair of integers modulo W 𝑊 W italic_W with d ( / W ) * 𝑑 superscript 𝑊 d\in(\mathbb{Z}/W\mathbb{Z})^{*} italic_d ∈ ( blackboard_Z / italic_W blackboard_Z ) start_POSTSUPERSCRIPT * end_POSTSUPERSCRIPT . Suppose that G G L 2 ( / W ) 𝐺 𝐺 subscript 𝐿 2 𝑊 G\subseteq GL_{2}(\mathbb{Z}/W\mathbb{Z}) italic_G ⊆ italic_G italic_L start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( blackboard_Z / italic_W blackboard_Z ) is any subgroup. We say that G 𝐺 G italic_G represents the pair ( t , d ) 𝑡 𝑑 (t,d) ( italic_t , italic_d ) if there is a matrix g G 𝑔 𝐺 g\in G italic_g ∈ italic_G satisfying

𝑡𝑟 ( g ) = t , det ( g ) = d . formulae-sequence 𝑡𝑟 𝑔 𝑡 𝑔 𝑑 \textrm{tr}\,(g)=t,\quad\det(g)=d. tr ( italic_g ) = italic_t , roman_det ( italic_g ) = italic_d .

Definition 4.2

A generalized function u 𝒢 ( d ) 𝑢 𝒢 superscript 𝑑 u\in\mathcal{G}(\mathbb{R}^{d}) italic_u ∈ caligraphic_G ( blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT ) (resp. 𝒢 ( d { 0 } ) 𝒢 superscript 𝑑 0 \mathcal{G}(\mathbb{R}^{d}\setminus\{0\}) caligraphic_G ( blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT ∖ { 0 } ) ) is called homogeneous of degree α 𝛼 \alpha italic_α , if for each λ + 𝜆 superscript \lambda\in\mathbb{R}^{+} italic_λ ∈ blackboard_R start_POSTSUPERSCRIPT + end_POSTSUPERSCRIPT ,

u ( λ x ) = λ α u ( x ) 𝑢 𝜆 𝑥 superscript 𝜆 𝛼 𝑢 𝑥 u(\lambda x)=\lambda^{\alpha}u(x) italic_u ( italic_λ italic_x ) = italic_λ start_POSTSUPERSCRIPT italic_α end_POSTSUPERSCRIPT italic_u ( italic_x ) (4.4)

holds in 𝒢 ( d ) 𝒢 superscript 𝑑 \mathcal{G}(\mathbb{R}^{d}) caligraphic_G ( blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT ) ( normal-( ( ( resp. 𝒢 ( d { 0 } ) ) fragments G fragments normal-( superscript 𝑑 fragments normal-{ 0 normal-} normal-) normal-) \mathcal{G}(\mathbb{R}^{d}\setminus\{0\})) caligraphic_G ( blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT ∖ { 0 } ) ) .


Definition 3.1 .

A vertex algebroid is a septuple 𝒜 = ( A , T , Ω , , γ , , , c ) fragments A fragments ( A , T , Ω , , γ , fragments , , c ) \mathcal{A}=(A,T,\Omega,\partial,\gamma,\langle,\rangle,c) caligraphic_A = ( italic_A , italic_T , roman_Ω , ∂ , italic_γ , ⟨ , ⟩ , italic_c ) where A 𝐴 A italic_A is a commutative algebra, T 𝑇 T italic_T is a Lie algebra acting by derivations on A 𝐴 A italic_A and equipped with the structure of an A 𝐴 A italic_A -module, Ω Ω \Omega roman_Ω is an A 𝐴 A italic_A -module equipped with the structure of a module over the Lie algebra T 𝑇 T italic_T , : A Ω : 𝐴 Ω \partial:A\to\Omega ∂ : italic_A → roman_Ω is an A 𝐴 A italic_A -derivation and a morphism of T 𝑇 T italic_T -modules, , : ( T Ω ) × ( T Ω ) A fragments fragments , : fragments ( T direct-sum Ω ) fragments ( T direct-sum Ω ) A \langle,\rangle:(T\oplus\Omega)\times(T\oplus\Omega)\to A ⟨ , ⟩ : ( italic_T ⊕ roman_Ω ) × ( italic_T ⊕ roman_Ω ) → italic_A is a symmetric bilinear pairing which is zero on Ω × Ω Ω Ω \Omega\times\Omega roman_Ω × roman_Ω , c : T × T Ω : 𝑐 𝑇 𝑇 Ω c:T\times T\to\Omega italic_c : italic_T × italic_T → roman_Ω is a skew symmetric bilinear pairing and γ : A × T Ω : 𝛾 𝐴 𝑇 Ω \gamma:A\times T\to\Omega italic_γ : italic_A × italic_T → roman_Ω is a bilinear map such that the following properties are satisfied for any a , b A 𝑎 𝑏 𝐴 a,b\in A italic_a , italic_b ∈ italic_A , τ , τ i , ν T 𝜏 subscript 𝜏 𝑖 𝜈 𝑇 \tau,\tau_{i},\nu\in T italic_τ , italic_τ start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT , italic_ν ∈ italic_T and ω Ω 𝜔 Ω \omega\in\Omega italic_ω ∈ roman_Ω :

[ τ , a ν ] = a [ τ , ν ] + τ ( a ) ν 𝜏 𝑎 𝜈 𝑎 𝜏 𝜈 𝜏 𝑎 𝜈 [\tau,a\nu]=a[\tau,\nu]+\tau(a)\nu [ italic_τ , italic_a italic_ν ] = italic_a [ italic_τ , italic_ν ] + italic_τ ( italic_a ) italic_ν
( a τ ) ( b ) = a τ ( b ) 𝑎 𝜏 𝑏 𝑎 𝜏 𝑏 (a\tau)(b)=a\tau(b) ( italic_a italic_τ ) ( italic_b ) = italic_a italic_τ ( italic_b )
τ , a = τ ( a ) 𝜏 𝑎 𝜏 𝑎 \langle\tau,\partial a\rangle=\tau(a) ⟨ italic_τ , ∂ italic_a ⟩ = italic_τ ( italic_a )
τ ( a ω ) = τ ( a ) ω + a τ ( w ) 𝜏 𝑎 𝜔 𝜏 𝑎 𝜔 𝑎 𝜏 𝑤 \tau(a\omega)=\tau(a)\omega+a\tau(w) italic_τ ( italic_a italic_ω ) = italic_τ ( italic_a ) italic_ω + italic_a italic_τ ( italic_w )
( a τ ) ( ω ) = a τ ( ω ) + τ , ω a 𝑎 𝜏 𝜔 𝑎 𝜏 𝜔 𝜏 𝜔 𝑎 (a\tau)(\omega)=a\tau(\omega)+\langle\tau,\omega\rangle\partial a ( italic_a italic_τ ) ( italic_ω ) = italic_a italic_τ ( italic_ω ) + ⟨ italic_τ , italic_ω ⟩ ∂ italic_a
τ ( ν , ω ) = [ τ , ν ] , ω + ν , τ ( ω ) 𝜏 𝜈 𝜔 𝜏 𝜈 𝜔 𝜈 𝜏 𝜔 \tau(\langle\nu,\omega\rangle)=\langle[\tau,\nu],\omega\rangle+\langle\nu,\tau% (\omega)\rangle italic_τ ( ⟨ italic_ν , italic_ω ⟩ ) = ⟨ [ italic_τ , italic_ν ] , italic_ω ⟩ + ⟨ italic_ν , italic_τ ( italic_ω ) ⟩
γ ( a , b τ ) = γ ( a b , τ ) - a γ ( b , τ ) - τ ( a ) b - τ ( b ) a 𝛾 𝑎 𝑏 𝜏 𝛾 𝑎 𝑏 𝜏 𝑎 𝛾 𝑏 𝜏 𝜏 𝑎 𝑏 𝜏 𝑏 𝑎 \gamma(a,b\tau)=\gamma(ab,\tau)-a\gamma(b,\tau)-\tau(a)\partial b-\tau(b)\partial a italic_γ ( italic_a , italic_b italic_τ ) = italic_γ ( italic_a italic_b , italic_τ ) - italic_a italic_γ ( italic_b , italic_τ ) - italic_τ ( italic_a ) ∂ italic_b - italic_τ ( italic_b ) ∂ italic_a
a τ 1 , τ 2 = a τ 1 , τ 2 + γ ( a , τ 1 ) , τ 2 - τ 1 τ 2 ( a ) 𝑎 subscript 𝜏 1 subscript 𝜏 2 𝑎 subscript 𝜏 1 subscript 𝜏 2 𝛾 𝑎 subscript 𝜏 1 subscript 𝜏 2 subscript 𝜏 1 subscript 𝜏 2 𝑎 \langle a\tau_{1},\tau_{2}\rangle=a\langle\tau_{1},\tau_{2}\rangle+\langle% \gamma(a,\tau_{1}),\tau_{2}\rangle-\tau_{1}\tau_{2}(a) ⟨ italic_a italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ = italic_a ⟨ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ + ⟨ italic_γ ( italic_a , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ) , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ - italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( italic_a )
c ( a τ 1 , τ 2 ) = a c ( τ 1 , τ 2 ) + γ ( a , [ τ 1 , τ 2 ] ) γ ( τ 2 ( a ) , τ 1 ) + τ 2 ( γ ( a , τ 1 ) ) 𝑐 𝑎 subscript 𝜏 1 subscript 𝜏 2 𝑎 𝑐 subscript 𝜏 1 subscript 𝜏 2 𝛾 𝑎 subscript 𝜏 1 subscript 𝜏 2 𝛾 subscript 𝜏 2 𝑎 subscript 𝜏 1 subscript 𝜏 2 𝛾 𝑎 subscript 𝜏 1 c(a\tau_{1},\tau_{2})=ac(\tau_{1},\tau_{2})+\gamma(a,[\tau_{1},\tau_{2}])% \gamma(\tau_{2}(a),\tau_{1})+\tau_{2}(\gamma(a,\tau_{1})) italic_c ( italic_a italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) = italic_a italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) + italic_γ ( italic_a , [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ] ) italic_γ ( italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( italic_a ) , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ) + italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( italic_γ ( italic_a , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ) )
- 1 2 τ 1 , τ 2 a + 1 2 τ 1 τ 2 ( a ) - 1 2 τ 2 , γ ( a , τ 1 ) 1 2 subscript 𝜏 1 subscript 𝜏 2 𝑎 1 2 subscript 𝜏 1 subscript 𝜏 2 𝑎 1 2 subscript 𝜏 2 𝛾 𝑎 subscript 𝜏 1 -\frac{1}{2}\langle\tau_{1},\tau_{2}\rangle\partial a+\frac{1}{2}\partial\tau_% {1}\tau_{2}(a)-\frac{1}{2}\partial\langle\tau_{2},\gamma(a,\tau_{1})\rangle - divide start_ARG 1 end_ARG start_ARG 2 end_ARG ⟨ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ ∂ italic_a + divide start_ARG 1 end_ARG start_ARG 2 end_ARG ∂ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( italic_a ) - divide start_ARG 1 end_ARG start_ARG 2 end_ARG ∂ ⟨ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_γ ( italic_a , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ) ⟩
[ τ 1 , τ 2 ] , τ 3 + τ 2 , [ τ 1 , τ 3 ] = τ 1 ( τ 2 , τ 3 ) - 1 2 τ 2 ( τ 1 , τ 3 ) - 1 2 τ 3 ( τ 1 , τ 2 ) subscript 𝜏 1 subscript 𝜏 2 subscript 𝜏 3 subscript 𝜏 2 subscript 𝜏 1 subscript 𝜏 3 subscript 𝜏 1 subscript 𝜏 2 subscript 𝜏 3 1 2 subscript 𝜏 2 subscript 𝜏 1 subscript 𝜏 3 1 2 subscript 𝜏 3 subscript 𝜏 1 subscript 𝜏 2 \langle[\tau_{1},\tau_{2}],\tau_{3}\rangle+\langle\tau_{2},[\tau_{1},\tau_{3}]% \rangle=\tau_{1}(\langle\tau_{2},\tau_{3}\rangle)-\frac{1}{2}\tau_{2}(\langle% \tau_{1},\tau_{3}\rangle)-\frac{1}{2}\tau_{3}(\langle\tau_{1},\tau_{2}\rangle) ⟨ [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ + ⟨ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ] ⟩ = italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ( ⟨ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ ) - divide start_ARG 1 end_ARG start_ARG 2 end_ARG italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( ⟨ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ ) - divide start_ARG 1 end_ARG start_ARG 2 end_ARG italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ( ⟨ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ )
+ τ 2 , c ( τ 1 , τ 3 ) + τ 3 , c ( τ 1 , τ 2 ) subscript 𝜏 2 𝑐 subscript 𝜏 1 subscript 𝜏 3 subscript 𝜏 3 𝑐 subscript 𝜏 1 subscript 𝜏 2 +\langle\tau_{2},c(\tau_{1},\tau_{3})\rangle+\langle\tau_{3},c(\tau_{1},\tau_{% 2})\rangle + ⟨ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) ⟩ + ⟨ italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT , italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) ⟩
d Lie c ( τ 1 , τ 2 , τ 3 ) = - 1 2 { [ τ 1 , τ 2 ] , τ 3 + [ τ 1 , τ 3 ] , τ 2 - [ τ 2 , τ 3 ] , τ 1 - τ 1 ( τ 2 , τ 3 ) fragments subscript 𝑑 Lie c fragments ( subscript 𝜏 1 , subscript 𝜏 2 , subscript 𝜏 3 ) 1 2 fragments { fragments fragments [ subscript 𝜏 1 , subscript 𝜏 2 ] , subscript 𝜏 3 fragments fragments [ subscript 𝜏 1 , subscript 𝜏 3 ] , subscript 𝜏 2 fragments fragments [ subscript 𝜏 2 , subscript 𝜏 3 ] , subscript 𝜏 1 subscript 𝜏 1 fragments ( fragments subscript 𝜏 2 , subscript 𝜏 3 ) d_{\textrm{Lie}}c(\tau_{1},\tau_{2},\tau_{3})=-\frac{1}{2}\partial\{\langle[% \tau_{1},\tau_{2}],\tau_{3}\rangle+\langle[\tau_{1},\tau_{3}],\tau_{2}\rangle-% \langle[\tau_{2},\tau_{3}],\tau_{1}\rangle-\tau_{1}(\langle\tau_{2},\tau_{3}\rangle) italic_d start_POSTSUBSCRIPT Lie end_POSTSUBSCRIPT italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) = - divide start_ARG 1 end_ARG start_ARG 2 end_ARG ∂ { ⟨ [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ + ⟨ [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ⟩ - ⟨ [ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ⟩ - italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ( ⟨ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ )
+ τ 2 ( τ 1 , τ 3 ) - 2 τ 3 , c ( τ 1 , τ 2 ) } fragments subscript 𝜏 2 fragments ( fragments subscript 𝜏 1 , subscript 𝜏 3 ) 2 fragments subscript 𝜏 3 , c fragments ( subscript 𝜏 1 , subscript 𝜏 2 ) } +\tau_{2}(\langle\tau_{1},\tau_{3}\rangle)-2\langle\tau_{3},c(\tau_{1},\tau_{2% })\rangle\} + italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ( ⟨ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ⟩ ) - 2 ⟨ italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT , italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) ⟩ }

where d Lie c ( τ 1 , τ 2 , τ 3 ) = τ 1 c ( τ 2 , τ 3 ) - τ 2 c ( τ 1 , τ 3 ) + τ 3 c ( τ 1 , τ 2 ) - c ( [ τ 1 , τ 2 ] , τ 3 ) + c ( [ τ 1 , τ 3 ] , τ 2 ) - c ( [ τ 2 , τ 3 ] , τ 1 ) subscript 𝑑 Lie 𝑐 subscript 𝜏 1 subscript 𝜏 2 subscript 𝜏 3 subscript 𝜏 1 𝑐 subscript 𝜏 2 subscript 𝜏 3 subscript 𝜏 2 𝑐 subscript 𝜏 1 subscript 𝜏 3 subscript 𝜏 3 𝑐 subscript 𝜏 1 subscript 𝜏 2 𝑐 subscript 𝜏 1 subscript 𝜏 2 subscript 𝜏 3 𝑐 subscript 𝜏 1 subscript 𝜏 3 subscript 𝜏 2 𝑐 subscript 𝜏 2 subscript 𝜏 3 subscript 𝜏 1 d_{\textrm{Lie}}c(\tau_{1},\tau_{2},\tau_{3})=\tau_{1}c(\tau_{2},\tau_{3})-% \tau_{2}c(\tau_{1},\tau_{3})+\tau_{3}c(\tau_{1},\tau_{2})-c([\tau_{1},\tau_{2}% ],\tau_{3})+c([\tau_{1},\tau_{3}],\tau_{2})-c([\tau_{2},\tau_{3}],\tau_{1}) italic_d start_POSTSUBSCRIPT Lie end_POSTSUBSCRIPT italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) = italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT italic_c ( italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) - italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) + italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT italic_c ( italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) - italic_c ( [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ) + italic_c ( [ italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT ) - italic_c ( [ italic_τ start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT , italic_τ start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT ] , italic_τ start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT ) . (cf. [GMS1] 1.1, 1.4)


Definition 4 .

The double Livernet–Loday operad L L 𝐿 subscript 𝐿 Planck-constant-over-2-pi {\mathrsfs{L}\!\mathrsfs{L}_{\hbar}} italic_L italic_L start_POSTSUBSCRIPT roman_ℏ end_POSTSUBSCRIPT is a quadratic operad over 𝕜 [ [ ] ] 𝕜 delimited-[] delimited-[] Planck-constant-over-2-pi \mathbbold{k}[[\hbar]] blackboard_k [ [ roman_ℏ ] ] generated by a commutative operation a , b a b maps-to 𝑎 𝑏 𝑎 𝑏 a,b\mapsto a\cdot b italic_a , italic_b ↦ italic_a ⋅ italic_b and a skew-commutative operation a , b [ a , b ] maps-to 𝑎 𝑏 𝑎 𝑏 a,b\mapsto[a,b] italic_a , italic_b ↦ [ italic_a , italic_b ] satisfying the identities


Definition 3.5 .

Let T V 𝑇 𝑉 T\subset V italic_T ⊂ italic_V be an open cone, x 𝑥 x italic_x be in T 𝑇 \partial T ∂ italic_T , and h h italic_h be a function from T 𝑇 T italic_T to \mathbb{R} blackboard_R satisfying

h ( ( 1 - λ ) x + λ y ) = log λ + h ( y ) 1 𝜆 𝑥 𝜆 𝑦 𝜆 𝑦 h((1-\lambda)x+\lambda y)=\log\lambda+h(y) italic_h ( ( 1 - italic_λ ) italic_x + italic_λ italic_y ) = roman_log italic_λ + italic_h ( italic_y ) (8)

whenever y 𝑦 y italic_y and ( 1 - λ ) x + λ y 1 𝜆 𝑥 𝜆 𝑦 (1-\lambda)x+\lambda y ( 1 - italic_λ ) italic_x + italic_λ italic_y are in T 𝑇 T italic_T and λ > 0 𝜆 0 \lambda>0 italic_λ > 0 . We define the extension of h h italic_h to τ ( T , x ) 𝜏 𝑇 𝑥 \tau(T,x) italic_τ ( italic_T , italic_x ) by

h | τ ( T , x ) ( y ) := - log λ y + h ( ( 1 - λ y ) x + λ y y ) , for all y τ ( T , x ) , fragments h superscript | 𝜏 𝑇 𝑥 fragments ( y ) assign subscript 𝜆 𝑦 h fragments ( fragments ( 1 subscript 𝜆 𝑦 ) x subscript 𝜆 𝑦 y ) , for all y τ ( T , x ) , h|^{\tau(T,x)}(y):=-\log\lambda_{y}+h((1-\lambda_{y})x+\lambda_{y}y),\qquad% \text{for all $y\in\tau(T,x),$} italic_h | start_POSTSUPERSCRIPT italic_τ ( italic_T , italic_x ) end_POSTSUPERSCRIPT ( italic_y ) := - roman_log italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT + italic_h ( ( 1 - italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT ) italic_x + italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT italic_y ) , for all italic_y ∈ italic_τ ( italic_T , italic_x ) ,

where λ y > 0 subscript 𝜆 𝑦 0 \lambda_{y}>0 italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT > 0 is chosen so that ( 1 - λ y ) x + λ y y 1 subscript 𝜆 𝑦 𝑥 subscript 𝜆 𝑦 𝑦 (1-\lambda_{y})x+\lambda_{y}y ( 1 - italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT ) italic_x + italic_λ start_POSTSUBSCRIPT italic_y end_POSTSUBSCRIPT italic_y is in T 𝑇 T italic_T .


Définition 2 .

Un fibré E 𝐸 E italic_E est dit c 𝑐 c italic_c -réel s’il existe une involution antilinéaire de E 𝐸 E italic_E dans E 𝐸 E italic_E relevant c 𝑐 c italic_c . Dans ce cas, on désigne par κ : Γ ( E ) Γ ( E ) normal-: 𝜅 normal-→ normal-Γ 𝐸 normal-Γ 𝐸 \kappa:\Gamma(E)\to\Gamma(E) italic_κ : roman_Γ ( italic_E ) → roman_Γ ( italic_E ) l’involution sur l’espace des sections de E 𝐸 E italic_E induite par c ^ normal-^ 𝑐 \hat{c} ^ start_ARG italic_c end_ARG :

κ ( s ) = c ^ - 1 s c . 𝜅 𝑠 superscript ^ 𝑐 1 𝑠 𝑐 \kappa(s)=\hat{c}^{-1}\circ s\circ c. italic_κ ( italic_s ) = ^ start_ARG italic_c end_ARG start_POSTSUPERSCRIPT - 1 end_POSTSUPERSCRIPT ∘ italic_s ∘ italic_c .

Une section s 𝑠 s italic_s de E 𝐸 E italic_E est dite symétrique si κ ( s ) = s 𝜅 𝑠 𝑠 \kappa(s)=s italic_κ ( italic_s ) = italic_s .


Definition 7.1

5.1 By ordering σ 𝜎 \sigma italic_σ we mean an enriched permutation it the following sense. Given d 𝑑 d italic_d positive real numbers n 1 , , n d subscript 𝑛 1 normal-⋯ subscript 𝑛 𝑑 n_{1},\cdots,n_{d} italic_n start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT , ⋯ , italic_n start_POSTSUBSCRIPT italic_d end_POSTSUBSCRIPT , σ 𝜎 \sigma italic_σ acts by a permutation on the indices so that n σ ( 1 ) n σ ( d ) subscript 𝑛 𝜎 1 normal-⋯ subscript 𝑛 𝜎 𝑑 n_{\sigma(1)}\leq\cdots\leq n_{\sigma(d)} italic_n start_POSTSUBSCRIPT italic_σ ( 1 ) end_POSTSUBSCRIPT ≤ ⋯ ≤ italic_n start_POSTSUBSCRIPT italic_σ ( italic_d ) end_POSTSUBSCRIPT . The permutation is enriched in the following way. It keep track whether after the permutation two consecutive numbers are equal. To set the notation, given 5 5 5 5 numbers, if

σ = ( 5 ( 31 ) 24 ) 𝜎 5 31 24 \sigma=(5(31)24) italic_σ = ( 5 ( 31 ) 24 )

then

n 5 < n 3 = n 1 < n 2 < n 4 . subscript 𝑛 5 subscript 𝑛 3 subscript 𝑛 1 subscript 𝑛 2 subscript 𝑛 4 n_{5}<n_{3}=n_{1}<n_{2}<n_{4}. italic_n start_POSTSUBSCRIPT 5 end_POSTSUBSCRIPT < italic_n start_POSTSUBSCRIPT 3 end_POSTSUBSCRIPT = italic_n start_POSTSUBSCRIPT 1 end_POSTSUBSCRIPT < italic_n start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT < italic_n start_POSTSUBSCRIPT 4 end_POSTSUBSCRIPT .

Also, σ ( 1 ) = 5 𝜎 1 5 \sigma(1)=5 italic_σ ( 1 ) = 5 , σ ( 2 ) = 3 𝜎 2 3 \sigma(2)=3 italic_σ ( 2 ) = 3 , σ ( 3 ) = 1 𝜎 3 1 \sigma(3)=1 italic_σ ( 3 ) = 1 , σ ( 4 ) = 2 𝜎 4 2 \sigma(4)=2 italic_σ ( 4 ) = 2 , σ ( 5 ) = 2 𝜎 5 2 \sigma(5)=2 italic_σ ( 5 ) = 2 . And

( 5 ( 31 ) 24 ) = ( 5 ( 13 ) 24 ) . 5 31 24 5 13 24 (5(31)24)=(5(13)24). ( 5 ( 31 ) 24 ) = ( 5 ( 13 ) 24 ) .

Definition 2.1 .

A germ of a curve singularity in characteristic 2 absent 2 \neq 2 ≠ 2 is called an A n subscript 𝐴 𝑛 A_{n} italic_A start_POSTSUBSCRIPT italic_n end_POSTSUBSCRIPT -singularity if it is formally isomorphic to

y 2 - x n + 1 = 0 , superscript 𝑦 2 superscript 𝑥 𝑛 1 0 y^{2}-x^{n+1}=0, italic_y start_POSTSUPERSCRIPT 2 end_POSTSUPERSCRIPT - italic_x start_POSTSUPERSCRIPT italic_n + 1 end_POSTSUPERSCRIPT = 0 ,

(see Artin [ 4 ] , and Greuel and Kröning [ 8 ] .)


Definition 12

For any integer h > 1 1 h>1 italic_h > 1 we define the map ϕ : 2 h 2 2 h - 1 normal-: italic-ϕ normal-→ subscript superscript 2 superscript subscript 2 superscript 2 1 \phi:\mathbb{Z}_{2^{h}}\to\mathbb{Z}_{2}^{2^{h-1}} italic_ϕ : blackboard_Z start_POSTSUBSCRIPT 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT end_POSTSUBSCRIPT → blackboard_Z start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT start_POSTSUPERSCRIPT 2 start_POSTSUPERSCRIPT italic_h - 1 end_POSTSUPERSCRIPT end_POSTSUPERSCRIPT as follows. If 0 a 2 h - 1 0 𝑎 superscript 2 1 0\leq a\leq 2^{h-1} 0 ≤ italic_a ≤ 2 start_POSTSUPERSCRIPT italic_h - 1 end_POSTSUPERSCRIPT , the image ϕ ( a ) italic-ϕ 𝑎 \phi(a) italic_ϕ ( italic_a ) is the binary word ( 000 111 ) 000 normal-⋯ 111 (000\cdots 111) ( 000 ⋯ 111 ) with Hamming weight equal to a 𝑎 a italic_a . If 2 h - 1 < a < 2 h superscript 2 1 𝑎 superscript 2 2^{h-1}<a<2^{h} 2 start_POSTSUPERSCRIPT italic_h - 1 end_POSTSUPERSCRIPT < italic_a < 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT , the image ϕ ( a ) italic-ϕ 𝑎 \phi(a) italic_ϕ ( italic_a ) is the binary word ( 111 000 ) 111 normal-⋯ 000 (111\cdots 000) ( 111 ⋯ 000 ) with Hamming weight equal to 2 h - a superscript 2 𝑎 2^{h}-a 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT - italic_a . We also define the maps β , γ : 2 h 2 2 h - 2 normal-: 𝛽 𝛾 normal-→ subscript superscript 2 superscript subscript 2 superscript 2 2 \beta,\gamma:\mathbb{Z}_{2^{h}}\to\mathbb{Z}_{2}^{2^{h-2}} italic_β , italic_γ : blackboard_Z start_POSTSUBSCRIPT 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT end_POSTSUBSCRIPT → blackboard_Z start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT start_POSTSUPERSCRIPT 2 start_POSTSUPERSCRIPT italic_h - 2 end_POSTSUPERSCRIPT end_POSTSUPERSCRIPT such that for each a 2 h 𝑎 subscript superscript 2 a\in\mathbb{Z}_{2^{h}} italic_a ∈ blackboard_Z start_POSTSUBSCRIPT 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT end_POSTSUBSCRIPT

ϕ ( a ) = ( β ( a ) , γ ( a ) ) . italic-ϕ 𝑎 𝛽 𝑎 𝛾 𝑎 \phi(a)=(\beta(a),\gamma(a)). italic_ϕ ( italic_a ) = ( italic_β ( italic_a ) , italic_γ ( italic_a ) ) .

Finally the maps ϕ italic-ϕ \phi italic_ϕ , β 𝛽 \beta italic_β , and γ 𝛾 \gamma italic_γ are extended in the obvious way to act on words in 2 h n superscript subscript superscript 2 𝑛 \mathbb{Z}_{2^{h}}^{n} blackboard_Z start_POSTSUBSCRIPT 2 start_POSTSUPERSCRIPT italic_h end_POSTSUPERSCRIPT end_POSTSUBSCRIPT start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT .


Definition 2.1 .

An algebra L 𝐿 L italic_L over a field F 𝐹 F italic_F is called a Leibniz algebra if the Leibniz identity

[ x , [ y , z ] ] = [ [ x , y ] , z ] - [ [ x , z ] , y ] 𝑥 𝑦 𝑧 𝑥 𝑦 𝑧 𝑥 𝑧 𝑦 [x,[y,z]]=[[x,y],z]-[[x,z],y] [ italic_x , [ italic_y , italic_z ] ] = [ [ italic_x , italic_y ] , italic_z ] - [ [ italic_x , italic_z ] , italic_y ]

holds for any x , y , z L , 𝑥 𝑦 𝑧 𝐿 x,y,z\in L, italic_x , italic_y , italic_z ∈ italic_L , where [ , ] fragments normal-[ normal-, normal-] [\ ,\ ] [ , ] is the multiplication in L . 𝐿 L. italic_L .


Definition 1 .

A group G 𝐺 G italic_G acting faithfully on the tree X * superscript 𝑋 X^{*} italic_X start_POSTSUPERSCRIPT * end_POSTSUPERSCRIPT is said to be self-similar if for every g G 𝑔 𝐺 g\in G italic_g ∈ italic_G and every x X 𝑥 𝑋 x\in X italic_x ∈ italic_X there exist h G 𝐺 h\in G italic_h ∈ italic_G and y X 𝑦 𝑋 y\in X italic_y ∈ italic_X such that

g ( x w ) = y h ( w ) 𝑔 𝑥 𝑤 𝑦 𝑤 g(xw)=yh(w) italic_g ( italic_x italic_w ) = italic_y italic_h ( italic_w )

for all w X * 𝑤 superscript 𝑋 w\in X^{*} italic_w ∈ italic_X start_POSTSUPERSCRIPT * end_POSTSUPERSCRIPT .


Definition .

Let 𝖠 𝖠 \mathsf{A} sansserif_A be a C * superscript 𝐶 C^{*} italic_C start_POSTSUPERSCRIPT * end_POSTSUPERSCRIPT -algebra with representations ( π , 𝗁 ) 𝜋 𝗁 (\pi,\mathsf{h}) ( italic_π , sansserif_h ) and ( π , 𝗁 ) superscript 𝜋 superscript 𝗁 (\pi^{\prime},\mathsf{h}^{\prime}) ( italic_π start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , sansserif_h start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) . A map δ : 𝖠 B ( 𝗁 ; 𝗁 ) : 𝛿 𝖠 𝐵 𝗁 superscript 𝗁 \delta:\mathsf{A}\to B(\mathsf{h};\mathsf{h}^{\prime}) italic_δ : sansserif_A → italic_B ( sansserif_h ; sansserif_h start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) is called a ( π , π ) superscript 𝜋 𝜋 (\pi^{\prime},\pi) ( italic_π start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_π ) - derivation if it satisfies

δ ( a b ) = δ ( a ) π ( b ) + π ( a ) δ ( b ) ; 𝛿 𝑎 𝑏 𝛿 𝑎 𝜋 𝑏 superscript 𝜋 𝑎 𝛿 𝑏 \delta(ab)=\delta(a)\pi(b)+\pi^{\prime}(a)\delta(b); italic_δ ( italic_a italic_b ) = italic_δ ( italic_a ) italic_π ( italic_b ) + italic_π start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_a ) italic_δ ( italic_b ) ;

it is inner if it is implemented by an operator T B ( 𝗁 ; 𝗁 ) 𝑇 𝐵 𝗁 superscript 𝗁 T\in B(\mathsf{h};\mathsf{h}^{\prime}) italic_T ∈ italic_B ( sansserif_h ; sansserif_h start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) in the sense that

δ : a π ( a ) T - T π ( a ) . : 𝛿 𝑎 superscript 𝜋 𝑎 𝑇 𝑇 𝜋 𝑎 \delta:a\to\pi^{\prime}(a)T-T\pi(a). italic_δ : italic_a → italic_π start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_a ) italic_T - italic_T italic_π ( italic_a ) .

Definition 3.7 .

Let B 𝐵 B italic_B be a G 𝐺 G italic_G -algebra and 𝕄 𝕄 \mathbb{M} blackboard_M a functor of \mathcal{B} caligraphic_B -modules. We say that 𝕄 𝕄 \mathbb{M} blackboard_M is a G 𝐺 {\mathcal{B}}G caligraphic_B italic_G -module if it has a G 𝐺 G italic_G -module structure which is compatible with the \mathcal{B} caligraphic_B -module structure, that is,

g ( b m ) = g ( b ) g ( m ) 𝑔 𝑏 𝑚 𝑔 𝑏 𝑔 𝑚 g(b\cdot m)=g(b)\cdot g(m) italic_g ( italic_b ⋅ italic_m ) = italic_g ( italic_b ) ⋅ italic_g ( italic_m )

for every g G 𝑔 𝐺 g\in G italic_g ∈ italic_G , b 𝑏 b\in{\mathcal{B}} italic_b ∈ caligraphic_B and m 𝕄 𝑚 𝕄 m\in\mathbb{M} italic_m ∈ blackboard_M .