Definition 16 (Validity of an embedded formula) .

Global validity ( v l d 𝑣 𝑙 𝑑 vld italic_v italic_l italic_d ) of an embedded formula ϕ italic-ϕ \phi italic_ϕ of E in HOL is defined by the equation

𝑣𝑙𝑑 ϕ = z . ϕ z formulae-sequence 𝑣𝑙𝑑 italic-ϕ for-all 𝑧 italic-ϕ 𝑧 \text{vld}\,\lfloor\phi\rfloor=\forall z.\lfloor\phi\rfloor z vld ⌊ italic_ϕ ⌋ = ∀ italic_z . ⌊ italic_ϕ ⌋ italic_z

Definition A.2 (size of the each tree in the forest) .

Let

τ = k / ϵ , 𝜏 𝑘 italic-ϵ \displaystyle\tau=k/\epsilon, italic_τ = italic_k / italic_ϵ ,

assuming that k / ϵ n / 16 𝑘 italic-ϵ 𝑛 16 k/\epsilon\leq n/16 italic_k / italic_ϵ ≤ italic_n / 16 . The size of each tree in the forest is

q = n / τ = n ϵ / k 𝑞 𝑛 𝜏 𝑛 italic-ϵ 𝑘 \displaystyle q=n/\tau=n\epsilon/k italic_q = italic_n / italic_τ = italic_n italic_ϵ / italic_k

Definition 4.1 .

Let ( L , A , ρ ) 𝐿 𝐴 𝜌 (L,A,\rho) ( italic_L , italic_A , italic_ρ ) be a 3-Lie-Rinehart algebra, ( R , A ) 𝑅 𝐴 (R,A) ( italic_R , italic_A ) be a 3-Lie A 𝐴 A italic_A -algebra and β : L L D e r ( R ) normal-: 𝛽 normal-→ 𝐿 𝐿 𝐷 𝑒 𝑟 𝑅 \beta:L\wedge L\rightarrow Der(R) italic_β : italic_L ∧ italic_L → italic_D italic_e italic_r ( italic_R ) be an action of ( L , A , ρ ) 𝐿 𝐴 𝜌 (L,A,\rho) ( italic_L , italic_A , italic_ρ ) on ( R , A ) 𝑅 𝐴 (R,A) ( italic_R , italic_A ) . If an A 𝐴 A italic_A -linear mapping ψ : L R normal-: 𝜓 normal-→ 𝐿 𝑅 \psi:L\rightarrow R italic_ψ : italic_L → italic_R has the property: for all x , y , z L 𝑥 𝑦 𝑧 𝐿 x,y,z\in L italic_x , italic_y , italic_z ∈ italic_L ,

(38) ψ ( [ x , y , z ] ) = [ ψ ( x ) , ψ ( y ) , ψ ( z ) ] + β ( x , y ) ψ ( z ) + β ( y , z ) ψ ( x ) + β ( z , x ) ψ ( y ) , 𝜓 𝑥 𝑦 𝑧 𝜓 𝑥 𝜓 𝑦 𝜓 𝑧 𝛽 𝑥 𝑦 𝜓 𝑧 𝛽 𝑦 𝑧 𝜓 𝑥 𝛽 𝑧 𝑥 𝜓 𝑦 \psi([x,y,z])=[\psi(x),\psi(y),\psi(z)]+\beta(x,y)\psi(z)+\beta(y,z)\psi(x)+% \beta(z,x)\psi(y), italic_ψ ( [ italic_x , italic_y , italic_z ] ) = [ italic_ψ ( italic_x ) , italic_ψ ( italic_y ) , italic_ψ ( italic_z ) ] + italic_β ( italic_x , italic_y ) italic_ψ ( italic_z ) + italic_β ( italic_y , italic_z ) italic_ψ ( italic_x ) + italic_β ( italic_z , italic_x ) italic_ψ ( italic_y ) ,

then ψ 𝜓 \psi italic_ψ is called a 3-Lie-Rinehart derivation from ( L , A , ρ ) 𝐿 𝐴 𝜌 (L,A,\rho) ( italic_L , italic_A , italic_ρ ) to ( R , A ) 𝑅 𝐴 (R,A) ( italic_R , italic_A ) , and D e r β ( L , R ) 𝐷 𝑒 subscript 𝑟 𝛽 𝐿 𝑅 Der_{\beta}(L,R) italic_D italic_e italic_r start_POSTSUBSCRIPT italic_β end_POSTSUBSCRIPT ( italic_L , italic_R ) denotes all 3-Lie-Rinehart derivations from ( L , A , ρ ) 𝐿 𝐴 𝜌 (L,A,\rho) ( italic_L , italic_A , italic_ρ ) to ( R , A ) 𝑅 𝐴 (R,A) ( italic_R , italic_A ) .


Definition 1 .

(cf. Nomizu [ 96 ] ) A homogeneous space M = G / H 𝑀 𝐺 𝐻 M=G/H italic_M = italic_G / italic_H is reductive if the Lie algebra 𝔤 𝔤 {\mathfrak{g}} fraktur_g of G 𝐺 G italic_G may be decomposed into a vector space direct sum of the Lie algebra 𝔥 𝔥 {\mathfrak{h}} fraktur_h of H 𝐻 H italic_H and an Ad ( H ) Ad 𝐻 {\mbox{\rm{Ad}}}(H) Ad ( italic_H ) -invariant subspace 𝔪 𝔪 {\mathfrak{m}} fraktur_m , that is

(6.15a) 𝔤 = 𝔥 + 𝔪 , 𝔥 𝔪 = , formulae-sequence 𝔤 𝔥 𝔪 𝔥 𝔪 {\mathfrak{g}}={\mathfrak{h}}+{\mathfrak{m}},~{}{\mathfrak{h}}\cap{\mathfrak{m% }}=\emptyset, fraktur_g = fraktur_h + fraktur_m , fraktur_h ∩ fraktur_m = ∅ ,
(6.15b) Ad ( H ) 𝔪 𝔪 . Ad 𝐻 𝔪 𝔪 {\mbox{\rm{Ad}}}(H){\mathfrak{m}}\subset{\mathfrak{m}}. Ad ( italic_H ) fraktur_m ⊂ fraktur_m .
Condition ( 6.15b ) implies
(6.15c) [ 𝔥 , 𝔪 ] 𝔪 𝔥 𝔪 𝔪 [{\mathfrak{h}},{\mathfrak{m}}]\subset{\mathfrak{m}} [ fraktur_h , fraktur_m ] ⊂ fraktur_m

and, conversely, if H 𝐻 H italic_H is connected, then ( 6.15c ) implies ( 6.15b ). Note that H 𝐻 H italic_H is always connected if M 𝑀 M italic_M is simply connected. The decomposition ( 6.15a ) verifying ( 6.15b ) is called a H 𝐻 H italic_H -stable decomposition .


Definition 2.1 .

A Lie algebra over a field 𝔽 𝔽 \mathbb{F} blackboard_F , is a vector space 𝔤 𝔤 \mathfrak{g} fraktur_g over 𝔽 𝔽 \mathbb{F} blackboard_F , equipped with a skew-symmetric bilinear map [ , ] : 𝔤 × 𝔤 𝔤 normal-: normal-⋅ normal-⋅ normal-→ 𝔤 𝔤 𝔤 [\,\cdot\,,\,\cdot\,]:\mathfrak{g}\times\mathfrak{g}\rightarrow\mathfrak{g} [ ⋅ , ⋅ ] : fraktur_g × fraktur_g → fraktur_g , satisfying the Jacobi identity :

[ x , [ y , z ] ] + [ y , [ z , x ] ] + [ z , [ x , y ] ] = 0 , x , y , z 𝔤 . formulae-sequence 𝑥 𝑦 𝑧 𝑦 𝑧 𝑥 𝑧 𝑥 𝑦 0 for-all 𝑥 𝑦 𝑧 𝔤 [x,[y,z]]+[y,[z,x]]+[z,[x,y]]=0,\ \ \forall\,x,y,z\in\mathfrak{g}. [ italic_x , [ italic_y , italic_z ] ] + [ italic_y , [ italic_z , italic_x ] ] + [ italic_z , [ italic_x , italic_y ] ] = 0 , ∀ italic_x , italic_y , italic_z ∈ fraktur_g .

The element [ x , y ] 𝔤 𝑥 𝑦 𝔤 [x,y]\in\mathfrak{g} [ italic_x , italic_y ] ∈ fraktur_g is referred to as the Lie bracket (or the Lie product) of x 𝑥 x italic_x and y 𝑦 y italic_y in 𝔤 𝔤 \mathfrak{g} fraktur_g .


Definition 2.2 .

A negation map on a 𝒯 𝒯 \mathcal{T} caligraphic_T -module 𝒜 𝒜 \mathcal{A} caligraphic_A is a semigroup isomorphism ( - ) : 𝒜 𝒜 normal-: normal-→ 𝒜 𝒜 (-):\mathcal{A}\to\mathcal{A} ( - ) : caligraphic_A → caligraphic_A of order 2 , absent 2 \leq 2, ≤ 2 , written a ( - ) a maps-to 𝑎 𝑎 a\mapsto(-)a italic_a ↦ ( - ) italic_a , together with a map ( - ) (-) ( - ) of order 2 absent 2 \leq 2 ≤ 2 on 𝒯 𝒯 \mathcal{T} caligraphic_T which also respects the 𝒯 𝒯 \mathcal{T} caligraphic_T -action in the sense that

( ( - ) a ) b = ( - ) ( a b ) = a ( ( - ) b ) 𝑎 𝑏 𝑎 𝑏 𝑎 𝑏 ((-)a)b=(-)(ab)=a((-)b) ( ( - ) italic_a ) italic_b = ( - ) ( italic_a italic_b ) = italic_a ( ( - ) italic_b )

for a 𝒯 , 𝑎 𝒯 a\in\mathcal{T}, italic_a ∈ caligraphic_T , b 𝒜 . 𝑏 𝒜 b\in\mathcal{A}. italic_b ∈ caligraphic_A .

Definition 3.6 .

A (systemic) Morita context is a six-tuple ( 𝒜 , 𝒜 , , , τ , τ ) 𝒜 superscript 𝒜 normal-′ superscript normal-′ 𝜏 superscript 𝜏 normal-′ (\mathcal{A},\mathcal{A}^{\prime},\mathcal{M},\mathcal{M}^{\prime},\tau,\tau^{% \prime}) ( caligraphic_A , caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , caligraphic_M , caligraphic_M start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_τ , italic_τ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) where 𝒜 , 𝒜 𝒜 superscript 𝒜 normal-′ \mathcal{A},\mathcal{A}^{\prime} caligraphic_A , caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT are systems, \mathcal{M} caligraphic_M is an 𝒜 - 𝒜 𝒜 superscript 𝒜 normal-′ \mathcal{A}-\mathcal{A}^{\prime} caligraphic_A - caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT bimodule, superscript normal-′ \mathcal{M}^{\prime} caligraphic_M start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT is an 𝒜 - 𝒜 superscript 𝒜 normal-′ 𝒜 \mathcal{A}^{\prime}-\mathcal{A} caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT - caligraphic_A bimodule, and

τ : 𝒜 𝒜 , τ : 𝒜 𝒜 : 𝜏 subscript tensor-product superscript 𝒜 superscript 𝒜 superscript 𝜏 : subscript tensor-product 𝒜 superscript superscript 𝒜 \tau:\mathcal{M}\otimes_{\mathcal{A}^{\prime}}\mathcal{M}^{\prime}\to\mathcal{% A},\qquad\tau^{\prime}:\mathcal{M}^{\prime}\otimes_{\mathcal{A}}\mathcal{M}\to% \mathcal{A}^{\prime} italic_τ : caligraphic_M ⊗ start_POSTSUBSCRIPT caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT end_POSTSUBSCRIPT caligraphic_M start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT → caligraphic_A , italic_τ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT : caligraphic_M start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ⊗ start_POSTSUBSCRIPT caligraphic_A end_POSTSUBSCRIPT caligraphic_M → caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT

are homomorphisms, linear on each side over 𝒜 𝒜 {\mathcal{A}} caligraphic_A and 𝒜 superscript 𝒜 normal-′ {\mathcal{A}^{\prime}} caligraphic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT respectively, which satisfy the following equations, writing ( x , x ) 𝑥 superscript 𝑥 normal-′ (x,x^{\prime}) ( italic_x , italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) for τ ( x , x ) 𝜏 𝑥 superscript 𝑥 normal-′ \tau(x,x^{\prime}) italic_τ ( italic_x , italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) and [ x , x ] superscript 𝑥 normal-′ 𝑥 [x^{\prime},x] [ italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_x ] for τ ( x , x ) 𝜏 superscript 𝑥 normal-′ 𝑥 \tau(x^{\prime},x) italic_τ ( italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_x ) :

  1. (i)

    ( x , x ) y = x [ x , y ] . 𝑥 superscript 𝑥 𝑦 𝑥 superscript 𝑥 𝑦 (x,x^{\prime})y=x[x^{\prime},y]. ( italic_x , italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) italic_y = italic_x [ italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_y ] .

  2. (ii)

    x ( x , y ) = [ x , x ] y . superscript 𝑥 𝑥 superscript 𝑦 superscript 𝑥 𝑥 superscript 𝑦 x^{\prime}(x,y^{\prime})=[x^{\prime},x]y^{\prime}. italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_x , italic_y start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) = [ italic_x start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_x ] italic_y start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT .


Definition 2.1 .

Let 𝔽 𝔽 \mathbb{F} blackboard_F be a field and T 𝑇 T italic_T an 𝔽 𝔽 \mathbb{F} blackboard_F -vector space endowed with a symplectic form ( , ) : T × T 𝔽 fragments fragments ( , ) : T T F (\,,\,)\colon T\times T\to\mathbb{F} ( , ) : italic_T × italic_T → blackboard_F , and a triple product [ , , ] : T × T × T T fragments fragments [ , , ] : T T T T [\,,\,,\,]\colon T\times T\times T\to T [ , , ] : italic_T × italic_T × italic_T → italic_T . It is said that ( T , [ , , ] , ( , ) ) fragments ( T , fragments [ , , ] , fragments ( , ) ) (T,[\,,\,,\,],(\,,\,)) ( italic_T , [ , , ] , ( , ) ) is a symplectic triple system if satisfies

(1) [ x , y , z ] = [ y , x , z ] , 𝑥 𝑦 𝑧 𝑦 𝑥 𝑧 \displaystyle[x,y,z]=[y,x,z], [ italic_x , italic_y , italic_z ] = [ italic_y , italic_x , italic_z ] ,
(2) - [ x , z , y ] = ( x , z ) y - ( x , y ) z + 2 ( y , z ) x , 𝑥 𝑧 𝑦 𝑥 𝑧 𝑦 𝑥 𝑦 𝑧 2 𝑦 𝑧 𝑥 \displaystyle-[x,z,y]=(x,z)y-(x,y)z+2(y,z)x, - [ italic_x , italic_z , italic_y ] = ( italic_x , italic_z ) italic_y - ( italic_x , italic_y ) italic_z + 2 ( italic_y , italic_z ) italic_x ,
(3) ] = [ [ x , y , u ] , v , w ] + [ u , [ x , y , v ] , w ] + [ u , v , [ x , y , w ] ] , fragments ] [ fragments [ x , y , u ] , v , w ] [ u , fragments [ x , y , v ] , w ] [ u , v , fragments [ x , y , w ] ] , \displaystyle]=[[x,y,u],v,w]+[u,[x,y,v],w]+[u,v,[x,y,w]], ] = [ [ italic_x , italic_y , italic_u ] , italic_v , italic_w ] + [ italic_u , [ italic_x , italic_y , italic_v ] , italic_w ] + [ italic_u , italic_v , [ italic_x , italic_y , italic_w ] ] ,
(4) ( [ x , y , u ] , v ) = - ( u , [ x , y , v ] ) , 𝑥 𝑦 𝑢 𝑣 𝑢 𝑥 𝑦 𝑣 \displaystyle([x,y,u],v)=-(u,[x,y,v]), ( [ italic_x , italic_y , italic_u ] , italic_v ) = - ( italic_u , [ italic_x , italic_y , italic_v ] ) ,

for any x , y , z , u , v , w T 𝑥 𝑦 𝑧 𝑢 𝑣 𝑤 𝑇 x,y,z,u,v,w\in T italic_x , italic_y , italic_z , italic_u , italic_v , italic_w ∈ italic_T .


Definition V.1 .

A fuzzy vector u n 𝑢 superscript 𝑛 u\in\mathcal{F}^{n} italic_u ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT is skew if it cannot be written as the sum of a fuzzy vector and a non-trivial symmetric fuzzy vector; that is, if

u = v w 𝑢 direct-sum 𝑣 𝑤 u=v\oplus w italic_u = italic_v ⊕ italic_w

for some v n 𝑣 superscript 𝑛 v\in\mathcal{F}^{n} italic_v ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT and w 𝗌 n 𝑤 subscript superscript 𝑛 𝗌 w\in\mathcal{F}^{n}_{\sf s} italic_w ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT start_POSTSUBSCRIPT sansserif_s end_POSTSUBSCRIPT , then w = 0 ~ 𝑤 ~ 0 w=\tilde{0} italic_w = ~ start_ARG 0 end_ARG .

Definition V.2 .

A fuzzy vector v n 𝑣 superscript 𝑛 v\in\mathcal{F}^{n} italic_v ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT is a Mareš core of a fuzzy vector u n 𝑢 superscript 𝑛 u\in\mathcal{F}^{n} italic_u ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT if v 𝑣 v italic_v is skew and

u = v w 𝑢 direct-sum 𝑣 𝑤 u=v\oplus w italic_u = italic_v ⊕ italic_w

for some symmetric fuzzy vector w 𝗌 n 𝑤 subscript superscript 𝑛 𝗌 w\in\mathcal{F}^{n}_{\sf s} italic_w ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT start_POSTSUBSCRIPT sansserif_s end_POSTSUBSCRIPT .

Definition VI.1 .

Fuzzy vectors u , v n 𝑢 𝑣 superscript 𝑛 u,v\in\mathcal{F}^{n} italic_u , italic_v ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT are Mareš equivalent , denoted by u M v subscript similar-to 𝑀 𝑢 𝑣 u\sim_{M}v italic_u ∼ start_POSTSUBSCRIPT italic_M end_POSTSUBSCRIPT italic_v , if there exist symmetric fuzzy vectors w , w 𝗌 n 𝑤 superscript 𝑤 subscript superscript 𝑛 𝗌 w,w^{\prime}\in\mathcal{F}^{n}_{\sf s} italic_w , italic_w start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ∈ caligraphic_F start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT start_POSTSUBSCRIPT sansserif_s end_POSTSUBSCRIPT such that

u w = v w . direct-sum 𝑢 𝑤 direct-sum 𝑣 superscript 𝑤 u\oplus w=v\oplus w^{\prime}. italic_u ⊕ italic_w = italic_v ⊕ italic_w start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT .

Definition 3.13 .

An element a L 𝑎 𝐿 a\in L italic_a ∈ italic_L is said to have the left CL-property if for all y C L ( x ) 𝑦 subscript 𝐶 𝐿 𝑥 y\in C_{L}(x) italic_y ∈ italic_C start_POSTSUBSCRIPT italic_L end_POSTSUBSCRIPT ( italic_x ) and x L 𝑥 𝐿 x\in L italic_x ∈ italic_L ,

[ [ x , a ] , y ] = 0 , 𝑥 𝑎 𝑦 0 \displaystyle[[x,a],y]=0, [ [ italic_x , italic_a ] , italic_y ] = 0 ,
[ [ a , x ] , y ] = 0 . 𝑎 𝑥 𝑦 0 \displaystyle[[a,x],y]=0. [ [ italic_a , italic_x ] , italic_y ] = 0 .

An element a L 𝑎 𝐿 a\in L italic_a ∈ italic_L is said to have the right CL-property if for all y C L ( x ) 𝑦 subscript 𝐶 𝐿 𝑥 y\in C_{L}(x) italic_y ∈ italic_C start_POSTSUBSCRIPT italic_L end_POSTSUBSCRIPT ( italic_x ) and x L 𝑥 𝐿 x\in L italic_x ∈ italic_L , we have

[ [ x , a ] , y ] = 0 , 𝑥 𝑎 𝑦 0 \displaystyle[[x,a],y]=0, [ [ italic_x , italic_a ] , italic_y ] = 0 ,
[ y , [ a , x ] ] = 0 . 𝑦 𝑎 𝑥 0 \displaystyle[y,[a,x]]=0. [ italic_y , [ italic_a , italic_x ] ] = 0 .

Definition 3.1

A cone is a commutative monoid C 𝐶 C italic_C together with a scalar multiplication by nonnegative real numbers satisfying the same axioms as for vector spaces; that is, C 𝐶 C italic_C is endowed with an addition ( x , y ) x + y : C × C C normal-: maps-to 𝑥 𝑦 𝑥 𝑦 normal-→ 𝐶 𝐶 𝐶 (x,y)\mapsto x+y\colon C\times C\to C ( italic_x , italic_y ) ↦ italic_x + italic_y : italic_C × italic_C → italic_C which is associative, commutative and admits a neutral element 0 0 , and with a scalar multiplication ( r , x ) r x : + × C C normal-: maps-to 𝑟 𝑥 normal-⋅ 𝑟 𝑥 normal-→ subscript 𝐶 𝐶 (r,x)\mapsto r\cdot x\colon\mathbb{R}_{+}\times C\to C ( italic_r , italic_x ) ↦ italic_r ⋅ italic_x : blackboard_R start_POSTSUBSCRIPT + end_POSTSUBSCRIPT × italic_C → italic_C satisfying the following axioms for all x , y C 𝑥 𝑦 𝐶 x,y\in C italic_x , italic_y ∈ italic_C and all r , s ¯ + 𝑟 𝑠 subscript normal-¯ r,s\in\overline{\mathbb{R}}_{+} italic_r , italic_s ∈ ¯ start_ARG blackboard_R end_ARG start_POSTSUBSCRIPT + end_POSTSUBSCRIPT :

r ( x + y ) = r x + r y 𝑟 𝑥 𝑦 𝑟 𝑥 𝑟 𝑦 \displaystyle r\cdot(x+y)=r\cdot x+r\cdot y italic_r ⋅ ( italic_x + italic_y ) = italic_r ⋅ italic_x + italic_r ⋅ italic_y ( r s ) x = r ( s x ) 𝑟 𝑠 𝑥 𝑟 𝑠 𝑥 \displaystyle(rs)\cdot x=r\cdot(s\cdot x) ( italic_r italic_s ) ⋅ italic_x = italic_r ⋅ ( italic_s ⋅ italic_x ) 0 x = 0 0 𝑥 0 \displaystyle 0\cdot x=0 0 ⋅ italic_x = 0
( r + s ) x = r x + s x 𝑟 𝑠 𝑥 𝑟 𝑥 𝑠 𝑥 \displaystyle(r+s)\cdot x=r\cdot x+s\cdot x ( italic_r + italic_s ) ⋅ italic_x = italic_r ⋅ italic_x + italic_s ⋅ italic_x 1 x = x 1 𝑥 𝑥 \displaystyle 1\cdot x=x 1 ⋅ italic_x = italic_x r 0 = 0 𝑟 0 0 \displaystyle r\cdot 0=0 italic_r ⋅ 0 = 0

We shall often write r x 𝑟 𝑥 rx italic_r italic_x instead of r x normal-⋅ 𝑟 𝑥 r\cdot x italic_r ⋅ italic_x for r + 𝑟 subscript r\in\mathbb{R}_{+} italic_r ∈ blackboard_R start_POSTSUBSCRIPT + end_POSTSUBSCRIPT and x C 𝑥 𝐶 x\in C italic_x ∈ italic_C .

A semitopological cone is a cone with a T 0 subscript 𝑇 0 T_{0} italic_T start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT topology that makes + + + and normal-⋅ \cdot separately continuous.

A topological cone is a cone with a T 0 subscript 𝑇 0 T_{0} italic_T start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT topology that makes + + + and normal-⋅ \cdot jointly continuous.


Definition 16 .

Let T 0 subscript 𝑇 0 T_{0} italic_T start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT denote the tree consisting of a single vertex. In the following four cases we define a partial block b 𝑏 b italic_b , its length which we denote length ( b ) normal-length 𝑏 \mathrm{length}(b) roman_length ( italic_b ) , and its R m subscript 𝑅 𝑚 R_{m} italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT -expression R m ( b ) subscript 𝑅 𝑚 𝑏 R_{m}(b) italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) . The expression R m ( b ) subscript 𝑅 𝑚 𝑏 R_{m}(b) italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) will be a monomial in x i subscript 𝑥 𝑖 x_{i} italic_x start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT and ( - a i a m ) ± 1 superscript subscript 𝑎 𝑖 subscript 𝑎 𝑚 plus-or-minus 1 (-\frac{a_{i}}{a_{m}})^{\pm 1} ( - divide start_ARG italic_a start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT end_ARG start_ARG italic_a start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT end_ARG ) start_POSTSUPERSCRIPT ± 1 end_POSTSUPERSCRIPT . We define b 𝑏 b italic_b to be:

1. A triple of integers

b = ( i , k , h ) 𝑏 𝑖 𝑘 b=(i,k,h) italic_b = ( italic_i , italic_k , italic_h )

where 1 h m - 1 1 𝑚 1 1\leq h\leq m-1 1 ≤ italic_h ≤ italic_m - 1 ; 2 k h + 1 2 𝑘 1 2\leq k\leq h+1 2 ≤ italic_k ≤ italic_h + 1 ; and h - ( k - 2 ) i m - 1 𝑘 2 𝑖 𝑚 1 h-(k-2)\leq i\leq m-1 italic_h - ( italic_k - 2 ) ≤ italic_i ≤ italic_m - 1 . Define

length ( b ) = k length 𝑏 𝑘 \mathrm{length}(b)=k roman_length ( italic_b ) = italic_k

and

R m ( b ) = x i ( - a m - 1 a m ) k - 2 - h ( - a m - 1 - h a m ) . subscript 𝑅 𝑚 𝑏 subscript 𝑥 𝑖 superscript subscript 𝑎 𝑚 1 subscript 𝑎 𝑚 𝑘 2 subscript 𝑎 𝑚 1 subscript 𝑎 𝑚 R_{m}(b)=x_{i}(-\frac{a_{m-1}}{a_{m}})^{k-2-h}(-\frac{a_{m-1-h}}{a_{m}}). italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) = italic_x start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT ( - divide start_ARG italic_a start_POSTSUBSCRIPT italic_m - 1 end_POSTSUBSCRIPT end_ARG start_ARG italic_a start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT end_ARG ) start_POSTSUPERSCRIPT italic_k - 2 - italic_h end_POSTSUPERSCRIPT ( - divide start_ARG italic_a start_POSTSUBSCRIPT italic_m - 1 - italic_h end_POSTSUBSCRIPT end_ARG start_ARG italic_a start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT end_ARG ) .

2. The triple

b = ( T 0 , k , k - 1 ) 𝑏 subscript 𝑇 0 𝑘 𝑘 1 b=(T_{0},k,k-1) italic_b = ( italic_T start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT , italic_k , italic_k - 1 )

where k 2 𝑘 2 k\geq 2 italic_k ≥ 2 . Define

length ( b ) = k length 𝑏 𝑘 \mathrm{length}(b)=k roman_length ( italic_b ) = italic_k

and

R m ( b ) = - a m - 1 - ( k - 1 ) a m . subscript 𝑅 𝑚 𝑏 subscript 𝑎 𝑚 1 𝑘 1 subscript 𝑎 𝑚 R_{m}(b)=-\frac{a_{m-1-(k-1)}}{a_{m}}. italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) = - divide start_ARG italic_a start_POSTSUBSCRIPT italic_m - 1 - ( italic_k - 1 ) end_POSTSUBSCRIPT end_ARG start_ARG italic_a start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT end_ARG .

3. For 0 i m - 1 0 𝑖 𝑚 1 0\leq i\leq m-1 0 ≤ italic_i ≤ italic_m - 1 , the 1 1 1 1 -tuple

b = ( i ) . 𝑏 𝑖 b=(i). italic_b = ( italic_i ) .

Define

length ( b ) = 1 length 𝑏 1 \mathrm{length}(b)=1 roman_length ( italic_b ) = 1

and

R m ( b ) = x i . subscript 𝑅 𝑚 𝑏 subscript 𝑥 𝑖 R_{m}(b)=x_{i}. italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) = italic_x start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT .

4. The 1-tuple

b = ( T 0 ) . 𝑏 subscript 𝑇 0 b=(T_{0}). italic_b = ( italic_T start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT ) .

Define

length ( b ) = 1 length 𝑏 1 \mathrm{length}(b)=1 roman_length ( italic_b ) = 1

and

R m ( b ) = - a m - 1 a m . subscript 𝑅 𝑚 𝑏 subscript 𝑎 𝑚 1 subscript 𝑎 𝑚 R_{m}(b)=-\frac{a_{m-1}}{a_{m}}. italic_R start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT ( italic_b ) = - divide start_ARG italic_a start_POSTSUBSCRIPT italic_m - 1 end_POSTSUBSCRIPT end_ARG start_ARG italic_a start_POSTSUBSCRIPT italic_m end_POSTSUBSCRIPT end_ARG .

Definition 2.6 .

For a 3 3 3 3 -dimensional terminal quotient singularity 𝗉 V 𝗉 𝑉 \mathsf{p}\in V sansserif_p ∈ italic_V of type 1 r ( 1 , a , r - a ) 1 𝑟 1 𝑎 𝑟 𝑎 \frac{1}{r}(1,a,r-a) divide start_ARG 1 end_ARG start_ARG italic_r end_ARG ( 1 , italic_a , italic_r - italic_a ) , we define

wp ( 𝗉 ) = a ( r - a ) wp 𝗉 𝑎 𝑟 𝑎 \operatorname{wp}(\mathsf{p})=a(r-a) roman_wp ( sansserif_p ) = italic_a ( italic_r - italic_a )

and call it the weight product of 𝗉 V 𝗉 𝑉 \mathsf{p}\in V sansserif_p ∈ italic_V .


Definition C.1 .

A function f : d m normal-: 𝑓 normal-→ superscript 𝑑 superscript 𝑚 f:{\mathbb{R}^{d}}\to\mathbb{R}^{m} italic_f : blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT → blackboard_R start_POSTSUPERSCRIPT italic_m end_POSTSUPERSCRIPT is called positively homogeneous, if for all α > 0 𝛼 0 \alpha>0 italic_α > 0 and all x d 𝑥 superscript 𝑑 x\in{\mathbb{R}^{d}} italic_x ∈ blackboard_R start_POSTSUPERSCRIPT italic_d end_POSTSUPERSCRIPT we have

f ( α x ) = α f ( x ) . 𝑓 𝛼 𝑥 𝛼 𝑓 𝑥 f(\alpha x)=\alpha f(x)\,. italic_f ( italic_α italic_x ) = italic_α italic_f ( italic_x ) .

Definition 1 (K-cooperativity)

Let 𝒦 n 𝒦 superscript 𝑛 \mathcal{K}\subseteq\mathbb{R}^{n} caligraphic_K ⊆ blackboard_R start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT be a pointed, solid, convex cone. A system x ˙ = f ( x ) normal-˙ 𝑥 𝑓 𝑥 \dot{x}=f(x) ˙ start_ARG italic_x end_ARG = italic_f ( italic_x ) is (strictly) K-cooperative if any trajectory ( x ( ) , δ x ( ) ) 𝑥 normal-⋅ 𝛿 𝑥 normal-⋅ (x(\cdot),\delta x(\cdot)) ( italic_x ( ⋅ ) , italic_δ italic_x ( ⋅ ) ) of the prolonged system

x ˙ = f ( x ) δ x ˙ = f ( x ) δ x , formulae-sequence ˙ 𝑥 𝑓 𝑥 ˙ 𝛿 𝑥 𝑓 𝑥 𝛿 𝑥 \dot{x}=f(x)\qquad\dot{\delta x}=\partial f(x)\delta x, ˙ start_ARG italic_x end_ARG = italic_f ( italic_x ) ˙ start_ARG italic_δ italic_x end_ARG = ∂ italic_f ( italic_x ) italic_δ italic_x , (4)

satisfies:

0 δ x ( 0 ) 𝒦 δ x ( t ) 𝑖𝑛𝑡 ( 𝒦 ) for t > 0 . 0 𝛿 𝑥 0 𝒦 𝛿 𝑥 𝑡 𝑖𝑛𝑡 𝒦 for 𝑡 0 0\neq\delta x(0)\in\mathcal{K}\implies\delta x(t)\in\mbox{int}(\mathcal{K})% \mbox{ for }t>0\ .\vspace{1mm} 0 ≠ italic_δ italic_x ( 0 ) ∈ caligraphic_K ⟹ italic_δ italic_x ( italic_t ) ∈ int ( caligraphic_K ) for italic_t > 0 . (5)

Definition 8

We say that ( ω , ϕ ) 𝜔 italic-ϕ (\omega,\phi) ( italic_ω , italic_ϕ ) are continuous if for all states s : { } + : 𝑠 s:\mathbb{N}\to\{\ast\}+\mathbb{N} italic_s : blackboard_N → { ∗ } + blackboard_N (which encode M , f 𝑀 𝑓 M,f italic_M , italic_f ) there exists some L 𝐿 L italic_L such that for any other input state s superscript 𝑠 s^{\prime} italic_s start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , if [ s ] ( L ) = [ s ] ( L ) delimited-[] 𝑠 𝐿 delimited-[] superscript 𝑠 𝐿 [{s}]({L})=[{s^{\prime}}]({L}) [ italic_s ] ( italic_L ) = [ italic_s start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ] ( italic_L ) then

( ω , ϕ ) ( s ) = ( ω , ϕ ) ( s ) . 𝜔 italic-ϕ 𝑠 𝜔 italic-ϕ superscript 𝑠 (\omega,\phi)(s)=(\omega,\phi)(s^{\prime}). ( italic_ω , italic_ϕ ) ( italic_s ) = ( italic_ω , italic_ϕ ) ( italic_s start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) .

Definition 4.1 (Weak Solution) .

A weak solution of equation ( 5 ) with the initial condition ρ 0 + ( [ 0 , 1 ) ) subscript 𝜌 0 superscript 0 1 \rho_{0}\in\mathcal{M}^{+}([0,1)) italic_ρ start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT ∈ caligraphic_M start_POSTSUPERSCRIPT + end_POSTSUPERSCRIPT ( [ 0 , 1 ) ) and the boundary condition μ + ( ( 0 , T ] ) 𝜇 superscript 0 𝑇 \mu\in\mathcal{M}^{+}((0,T]) italic_μ ∈ caligraphic_M start_POSTSUPERSCRIPT + end_POSTSUPERSCRIPT ( ( 0 , italic_T ] ) is a function ρ : [ 0 , T ] + ( [ 0 , 1 ) ) normal-: 𝜌 normal-→ 0 𝑇 superscript 0 1 \rho:[0,T]\to\mathcal{M}^{+}([0,1)) italic_ρ : [ 0 , italic_T ] → caligraphic_M start_POSTSUPERSCRIPT + end_POSTSUPERSCRIPT ( [ 0 , 1 ) ) , such that W : [ 0 , T ] ρ t ( [ 0 , 1 ) ) normal-: 𝑊 maps-to 0 𝑇 subscript 𝜌 𝑡 0 1 W\colon[0,T]\mapsto\rho_{t}([0,1)) italic_W : [ 0 , italic_T ] ↦ italic_ρ start_POSTSUBSCRIPT italic_t end_POSTSUBSCRIPT ( [ 0 , 1 ) ) is integrable and such that for every τ [ 0 , T ] 𝜏 0 𝑇 \tau\in[0,T] italic_τ ∈ [ 0 , italic_T ] and for every φ Ψ 𝜑 normal-Ψ \varphi\in\Psi italic_φ ∈ roman_Ψ that satisfies

φ ( t , 1 ) = 0 , for all t [ 0 , τ ] , formulae-sequence 𝜑 𝑡 1 0 for all 𝑡 0 𝜏 \varphi(t,1)=0,\mbox{ for all }t\in[0,\tau], italic_φ ( italic_t , 1 ) = 0 , for all italic_t ∈ [ 0 , italic_τ ] , (37)

one has

( 0 , τ ] [ 0 , 1 ) ( t φ ( t , x ) + α ( W ( t ) ) x φ ( t , x ) ) 𝑑 ρ t ( x ) 𝑑 t + ( 0 , τ ] φ ( t , 0 ) 𝑑 μ ( t ) subscript 0 𝜏 subscript 0 1 subscript 𝑡 𝜑 𝑡 𝑥 𝛼 𝑊 𝑡 subscript 𝑥 𝜑 𝑡 𝑥 differential-d subscript 𝜌 𝑡 𝑥 differential-d 𝑡 subscript 0 𝜏 𝜑 𝑡 0 differential-d 𝜇 𝑡 \displaystyle\int_{(0,\tau]}\int_{[0,1)}\left(\partial_{t}\varphi(t,x)+\alpha(% W(t))\partial_{x}\varphi(t,x)\right)\,d\rho_{t}(x)\,dt+\int_{(0,\tau]}\varphi(% t,0)\,d\mu(t) ∫ start_POSTSUBSCRIPT ( 0 , italic_τ ] end_POSTSUBSCRIPT ∫ start_POSTSUBSCRIPT [ 0 , 1 ) end_POSTSUBSCRIPT ( ∂ start_POSTSUBSCRIPT italic_t end_POSTSUBSCRIPT italic_φ ( italic_t , italic_x ) + italic_α ( italic_W ( italic_t ) ) ∂ start_POSTSUBSCRIPT italic_x end_POSTSUBSCRIPT italic_φ ( italic_t , italic_x ) ) italic_d italic_ρ start_POSTSUBSCRIPT italic_t end_POSTSUBSCRIPT ( italic_x ) italic_d italic_t + ∫ start_POSTSUBSCRIPT ( 0 , italic_τ ] end_POSTSUBSCRIPT italic_φ ( italic_t , 0 ) italic_d italic_μ ( italic_t )
- [ 0 , 1 ) φ ( τ , x ) 𝑑 ρ τ ( x ) + [ 0 , 1 ) φ ( 0 , x ) 𝑑 ρ 0 ( x ) = 0 . subscript 0 1 𝜑 𝜏 𝑥 differential-d subscript 𝜌 𝜏 𝑥 subscript 0 1 𝜑 0 𝑥 differential-d subscript 𝜌 0 𝑥 0 \displaystyle-\int_{[0,1)}\varphi(\tau,x)\,d\rho_{\tau}(x)+\int_{[0,1)}\varphi% (0,x)\,d\rho_{0}(x)=0. - ∫ start_POSTSUBSCRIPT [ 0 , 1 ) end_POSTSUBSCRIPT italic_φ ( italic_τ , italic_x ) italic_d italic_ρ start_POSTSUBSCRIPT italic_τ end_POSTSUBSCRIPT ( italic_x ) + ∫ start_POSTSUBSCRIPT [ 0 , 1 ) end_POSTSUBSCRIPT italic_φ ( 0 , italic_x ) italic_d italic_ρ start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT ( italic_x ) = 0 . (38)

Definition 2.1 .

For any non-degenerate quadratic space ( V , q ) 𝑉 𝑞 (V,q) ( italic_V , italic_q ) of dimension m 𝑚 m italic_m over F 𝐹 F italic_F , put

( v , v ) = 1 2 ( q ( v + v ) - q ( v ) - q ( v ) ) . 𝑣 superscript 𝑣 1 2 𝑞 𝑣 superscript 𝑣 𝑞 𝑣 𝑞 superscript 𝑣 (v,v^{\prime})=\tfrac{1}{2}(q(v+v^{\prime})-q(v)-q(v^{\prime})). ( italic_v , italic_v start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) = divide start_ARG 1 end_ARG start_ARG 2 end_ARG ( italic_q ( italic_v + italic_v start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) - italic_q ( italic_v ) - italic_q ( italic_v start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) ) . (2.2)

Then we define the determinant det ( V ) 𝑉 \det(V) roman_det ( italic_V ) and the discriminant disc ( V ) normal-disc 𝑉 \operatorname{disc}(V) roman_disc ( italic_V ) of ( V , q ) 𝑉 𝑞 (V,q) ( italic_V , italic_q ) by

det ( V ) 𝑉 \displaystyle\det(V) roman_det ( italic_V ) = det ( ( a i , a j ) i , j ) ( mod ( F × ) 2 ) , absent subscript subscript 𝑎 𝑖 subscript 𝑎 𝑗 𝑖 𝑗 mod superscript superscript 𝐹 2 \displaystyle=\det((a_{i},a_{j})_{i,j})\ \left(\mathrm{mod}(F^{\times})^{2}% \right), = roman_det ( ( italic_a start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT , italic_a start_POSTSUBSCRIPT italic_j end_POSTSUBSCRIPT ) start_POSTSUBSCRIPT italic_i , italic_j end_POSTSUBSCRIPT ) ( roman_mod ( italic_F start_POSTSUPERSCRIPT × end_POSTSUPERSCRIPT ) start_POSTSUPERSCRIPT 2 end_POSTSUPERSCRIPT ) ,
disc ( V ) disc 𝑉 \displaystyle\operatorname{disc}(V) roman_disc ( italic_V ) = ( - 1 ) ( m - 1 ) m 2 det ( V ) ( mod ( F × ) 2 ) , absent superscript 1 𝑚 1 𝑚 2 𝑉 mod superscript superscript 𝐹 2 \displaystyle=(-1)^{\frac{(m-1)m}{2}}\det(V)\ \left(\mathrm{mod}(F^{\times})^{% 2}\right), = ( - 1 ) start_POSTSUPERSCRIPT divide start_ARG ( italic_m - 1 ) italic_m end_ARG start_ARG 2 end_ARG end_POSTSUPERSCRIPT roman_det ( italic_V ) ( roman_mod ( italic_F start_POSTSUPERSCRIPT × end_POSTSUPERSCRIPT ) start_POSTSUPERSCRIPT 2 end_POSTSUPERSCRIPT ) ,

where { a i } subscript 𝑎 𝑖 \{a_{i}\} { italic_a start_POSTSUBSCRIPT italic_i end_POSTSUBSCRIPT } is a basis of V 𝑉 V italic_V . These are elements of F × / ( F × ) 2 superscript 𝐹 superscript superscript 𝐹 2 F^{\times}/(F^{\times})^{2} italic_F start_POSTSUPERSCRIPT × end_POSTSUPERSCRIPT / ( italic_F start_POSTSUPERSCRIPT × end_POSTSUPERSCRIPT ) start_POSTSUPERSCRIPT 2 end_POSTSUPERSCRIPT and independent of the choice of a basis.


Definition 3.5 .

Let 𝒜 X 𝒜 𝑋 \mathcal{A}\subseteq\partial X caligraphic_A ⊆ ∂ italic_X and Y 𝑌 \mathcal{B}\subseteq\partial Y caligraphic_B ⊆ ∂ italic_Y be subsets. A map f : 𝒜 : 𝑓 𝒜 f\colon\mathcal{A}\rightarrow\mathcal{B} italic_f : caligraphic_A → caligraphic_B is Möbius if f 4 ( 𝒜 ( X ) 𝒜 4 ) 𝒜 ( Y ) superscript 𝑓 4 𝒜 𝑋 superscript 𝒜 4 𝒜 𝑌 {f^{4}(\mathscr{A}(X)\cap\mathcal{A}^{4})\subseteq\mathscr{A}(Y)} italic_f start_POSTSUPERSCRIPT 4 end_POSTSUPERSCRIPT ( script_A ( italic_X ) ∩ caligraphic_A start_POSTSUPERSCRIPT 4 end_POSTSUPERSCRIPT ) ⊆ script_A ( italic_Y ) and, for each ( x , y , z , w ) 𝒜 ( X ) 𝒜 4 𝑥 𝑦 𝑧 𝑤 𝒜 𝑋 superscript 𝒜 4 (x,y,z,w)\in\mathscr{A}(X)\cap\mathcal{A}^{4} ( italic_x , italic_y , italic_z , italic_w ) ∈ script_A ( italic_X ) ∩ caligraphic_A start_POSTSUPERSCRIPT 4 end_POSTSUPERSCRIPT , we have

cr ( f ( x ) , f ( y ) , f ( z ) , f ( w ) ) = cr ( x , y , z , w ) . cr 𝑓 𝑥 𝑓 𝑦 𝑓 𝑧 𝑓 𝑤 cr 𝑥 𝑦 𝑧 𝑤 \mathrm{cr}(f(x),f(y),f(z),f(w))=\mathrm{cr}(x,y,z,w). roman_cr ( italic_f ( italic_x ) , italic_f ( italic_y ) , italic_f ( italic_z ) , italic_f ( italic_w ) ) = roman_cr ( italic_x , italic_y , italic_z , italic_w ) .

The latter happens if and only if crt ( f ( x ) , f ( y ) , f ( z ) , f ( w ) ) = crt ( x , y , z , w ) crt 𝑓 𝑥 𝑓 𝑦 𝑓 𝑧 𝑓 𝑤 crt 𝑥 𝑦 𝑧 𝑤 \mathrm{crt}(f(x),f(y),f(z),f(w))=\mathrm{crt}(x,y,z,w) roman_crt ( italic_f ( italic_x ) , italic_f ( italic_y ) , italic_f ( italic_z ) , italic_f ( italic_w ) ) = roman_crt ( italic_x , italic_y , italic_z , italic_w ) for all 4-tuples ( x , y , z , w ) 𝒜 ( X ) 𝒜 4 𝑥 𝑦 𝑧 𝑤 𝒜 𝑋 superscript 𝒜 4 {(x,y,z,w)\in\mathscr{A}(X)\cap\mathcal{A}^{4}} ( italic_x , italic_y , italic_z , italic_w ) ∈ script_A ( italic_X ) ∩ caligraphic_A start_POSTSUPERSCRIPT 4 end_POSTSUPERSCRIPT .


Definition 2.4 .

Let ( 𝔤 , [ , ] 𝔤 , ϕ 𝔤 ) 𝔤 subscript 𝔤 subscript italic-ϕ 𝔤 (\mathfrak{g},[\cdot,\cdot]_{\mathfrak{g}},\phi_{{}_{\mathfrak{g}}}) ( fraktur_g , [ ⋅ , ⋅ ] start_POSTSUBSCRIPT fraktur_g end_POSTSUBSCRIPT , italic_ϕ start_POSTSUBSCRIPT start_FLOATSUBSCRIPT fraktur_g end_FLOATSUBSCRIPT end_POSTSUBSCRIPT ) be a Hom-Lie algebra. Two representations ( V , β , ρ ) 𝑉 𝛽 𝜌 (V,\beta,\rho) ( italic_V , italic_β , italic_ρ ) and ( V , β , ρ ) superscript 𝑉 superscript 𝛽 superscript 𝜌 (V^{\prime},\beta^{\prime},\rho^{\prime}) ( italic_V start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_ρ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) are called equivalent if there exists a linear isomorphism φ : V V : 𝜑 𝑉 superscript 𝑉 \varphi:V\rightarrow V^{\prime} italic_φ : italic_V → italic_V start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT such that

(2.4) φ ρ ( x ) = ρ ( x ) φ , β φ ( x ) = φ β ( x ) , x 𝔤 . formulae-sequence 𝜑 𝜌 𝑥 superscript 𝜌 𝑥 𝜑 formulae-sequence superscript 𝛽 𝜑 𝑥 𝜑 𝛽 𝑥 for-all 𝑥 𝔤 \varphi\rho(x)=\rho^{\prime}(x)\varphi,\;\;\beta^{\prime}\varphi(x)=\varphi% \beta(x),\forall x\in\mathfrak{g}. italic_φ italic_ρ ( italic_x ) = italic_ρ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_x ) italic_φ , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT italic_φ ( italic_x ) = italic_φ italic_β ( italic_x ) , ∀ italic_x ∈ fraktur_g .

Definition 1

A metric d : 𝔽 2 n × 𝔽 2 n normal-: 𝑑 normal-→ superscript subscript 𝔽 2 𝑛 superscript subscript 𝔽 2 𝑛 d:\mathbb{F}_{2}^{n}\times\mathbb{F}_{2}^{n}\to\mathbb{R} italic_d : blackboard_F start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT × blackboard_F start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT → blackboard_R is said to be translation-invariant if

d ( 𝐱 + 𝐳 , 𝐲 + 𝐳 ) = d ( 𝐱 , 𝐲 ) 𝑑 𝐱 𝐳 𝐲 𝐳 𝑑 𝐱 𝐲 d(\mathbf{x}+\mathbf{z},\mathbf{y}+\mathbf{z})=d(\mathbf{x},\mathbf{y}) italic_d ( bold_x + bold_z , bold_y + bold_z ) = italic_d ( bold_x , bold_y )

for every 𝐱 , 𝐲 , 𝐳 𝔽 2 n 𝐱 𝐲 𝐳 superscript subscript 𝔽 2 𝑛 \mathbf{x},\mathbf{y},\mathbf{z}\in\mathbb{F}_{2}^{n} bold_x , bold_y , bold_z ∈ blackboard_F start_POSTSUBSCRIPT 2 end_POSTSUBSCRIPT start_POSTSUPERSCRIPT italic_n end_POSTSUPERSCRIPT .


Definiton 2.3 .

A solution of τ α , p u = λ u subscript 𝜏 𝛼 𝑝 𝑢 𝜆 𝑢 \tau_{\alpha,p}u=\lambda u italic_τ start_POSTSUBSCRIPT italic_α , italic_p end_POSTSUBSCRIPT italic_u = italic_λ italic_u which satisfies at a point l [ a , b ] \ { p } 𝑙 normal-\ 𝑎 𝑏 𝑝 l\in[a,b]\backslash\{p\} italic_l ∈ [ italic_a , italic_b ] \ { italic_p } the boundary condition

u ( l ) c o s θ + u ( l ) s e n θ = 0 , θ [ 0 , π ) formulae-sequence 𝑢 𝑙 𝑐 𝑜 𝑠 𝜃 superscript 𝑢 𝑙 𝑠 𝑒 𝑛 𝜃 0 𝜃 0 𝜋 u(l)cos\theta+u^{\prime}(l)sen\theta=0,\qquad\theta\in[0,\pi) italic_u ( italic_l ) italic_c italic_o italic_s italic_θ + italic_u start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ( italic_l ) italic_s italic_e italic_n italic_θ = 0 , italic_θ ∈ [ 0 , italic_π )

will be denoted by u l , α ( λ ) subscript 𝑢 𝑙 𝛼 𝜆 u_{l,\alpha}(\lambda) italic_u start_POSTSUBSCRIPT italic_l , italic_α end_POSTSUBSCRIPT ( italic_λ ) .


Definition 2.1 .

[ 3 ] [ 3 ] {}^{\@@cite[cite]{[\@@bibref{}{Scheunert}{}{}]}} start_FLOATSUPERSCRIPT end_FLOATSUPERSCRIPT Let Γ normal-Γ \Gamma roman_Γ be an abelian group. A bi-character on Γ normal-Γ \Gamma roman_Γ is a map ϵ : Γ × Γ 𝕂 \ { 0 } normal-: italic-ϵ normal-→ normal-Γ normal-Γ normal-\ 𝕂 0 \epsilon:\Gamma\times\Gamma\rightarrow\mathbb{K}\backslash\{0\} italic_ϵ : roman_Γ × roman_Γ → blackboard_K \ { 0 } satisfying

( 1 ) ϵ ( α , β ) ϵ ( β , α ) = 1 , 1 italic-ϵ 𝛼 𝛽 italic-ϵ 𝛽 𝛼 1 \displaystyle(1)~{}~{}\epsilon(\alpha,\beta)\epsilon(\beta,\alpha)=1, ( 1 ) italic_ϵ ( italic_α , italic_β ) italic_ϵ ( italic_β , italic_α ) = 1 ,
( 2 ) ϵ ( α , β + γ ) = ϵ ( α , β ) ϵ ( α , γ ) , 2 italic-ϵ 𝛼 𝛽 𝛾 italic-ϵ 𝛼 𝛽 italic-ϵ 𝛼 𝛾 \displaystyle(2)~{}~{}\epsilon(\alpha,\beta+\gamma)=\epsilon(\alpha,\beta)% \epsilon(\alpha,\gamma), ( 2 ) italic_ϵ ( italic_α , italic_β + italic_γ ) = italic_ϵ ( italic_α , italic_β ) italic_ϵ ( italic_α , italic_γ ) ,
( 3 ) ϵ ( α + β , γ ) = ϵ ( α , γ ) ϵ ( β , γ ) , 3 italic-ϵ 𝛼 𝛽 𝛾 italic-ϵ 𝛼 𝛾 italic-ϵ 𝛽 𝛾 \displaystyle(3)~{}~{}\epsilon(\alpha+\beta,\gamma)=\epsilon(\alpha,\gamma)% \epsilon(\beta,\gamma), ( 3 ) italic_ϵ ( italic_α + italic_β , italic_γ ) = italic_ϵ ( italic_α , italic_γ ) italic_ϵ ( italic_β , italic_γ ) ,

for any α , β Γ 𝛼 𝛽 normal-Γ \alpha,\beta\in\Gamma italic_α , italic_β ∈ roman_Γ .

Definition 2.2 .

[ 3 ] [ 3 ] {}^{\@@cite[cite]{[\@@bibref{}{Scheunert}{}{}]}} start_FLOATSUPERSCRIPT end_FLOATSUPERSCRIPT A Lie color algebra is a triple ( L , [ , ] , ε ) 𝐿 normal-⋅ normal-⋅ 𝜀 (L,[\cdot,\cdot],\varepsilon) ( italic_L , [ ⋅ , ⋅ ] , italic_ε ) consisting of a Γ normal-Γ \Gamma roman_Γ -graded space L 𝐿 L italic_L , an even bilinear mapping [ , ] : L × L L normal-: normal-⋅ normal-⋅ normal-→ 𝐿 𝐿 𝐿 [\cdot,\cdot]:L\times L\rightarrow L [ ⋅ , ⋅ ] : italic_L × italic_L → italic_L , and a bi-character ε 𝜀 \varepsilon italic_ε on Γ normal-Γ \Gamma roman_Γ satisfying the following conditions,

[ x , y ] = - ε ( x , y ) [ y , x ] , 𝑥 𝑦 𝜀 𝑥 𝑦 𝑦 𝑥 \displaystyle[x,y]=-\varepsilon(x,y)[y,x], [ italic_x , italic_y ] = - italic_ε ( italic_x , italic_y ) [ italic_y , italic_x ] ,
ε ( z , x ) [ x , [ y , z ] ] + ε ( x , y ) [ y , [ z , x ] ] + ε ( y , z ) [ z , [ x , y ] ] = 0 , 𝜀 𝑧 𝑥 𝑥 𝑦 𝑧 𝜀 𝑥 𝑦 𝑦 𝑧 𝑥 𝜀 𝑦 𝑧 𝑧 𝑥 𝑦 0 \displaystyle\varepsilon(z,x)[x,[y,z]]+\varepsilon(x,y)[y,[z,x]]+\varepsilon(y% ,z)[z,[x,y]]=0, italic_ε ( italic_z , italic_x ) [ italic_x , [ italic_y , italic_z ] ] + italic_ε ( italic_x , italic_y ) [ italic_y , [ italic_z , italic_x ] ] + italic_ε ( italic_y , italic_z ) [ italic_z , [ italic_x , italic_y ] ] = 0 ,

for any x , y , z L 𝑥 𝑦 𝑧 𝐿 x,y,z\in L italic_x , italic_y , italic_z ∈ italic_L .


Definition .

Let : n × n n : subscript 𝑛 subscript 𝑛 subscript 𝑛 \hbox to 7.0pt{\hrulefill}\cdot\hbox to 7.0pt{\hrulefill}\colon\mathscr{F}_{n}% \times\partial\mathscr{F}_{n}\to\partial\mathscr{F}_{n} ⋅ : script_F start_POSTSUBSCRIPT italic_n end_POSTSUBSCRIPT × ∂ script_F start_POSTSUBSCRIPT italic_n end_POSTSUBSCRIPT → ∂ script_F start_POSTSUBSCRIPT italic_n end_POSTSUBSCRIPT be the map given by

(4.10) x [ ω ] = [ x ω ] , 𝑥 delimited-[] 𝜔 delimited-[] 𝑥 𝜔 x\cdot[\omega]=[x\omega], italic_x ⋅ [ italic_ω ] = [ italic_x italic_ω ] ,

where x ω : n : 𝑥 𝜔 subscript 𝑛 x\omega\colon\mathbb{N}\to\mathscr{F}_{n} italic_x italic_ω : blackboard_N → script_F start_POSTSUBSCRIPT italic_n end_POSTSUBSCRIPT is given by ( x ω ) ( n ) = x ω ( n ) 𝑥 𝜔 𝑛 𝑥 𝜔 𝑛 (x\omega)(n)=x\omega(n) ( italic_x italic_ω ) ( italic_n ) = italic_x italic_ω ( italic_n )


Definition 2.1 .

For a Borel probability measure μ 𝜇 \mu italic_μ , we denote its Lebesgue decomposition by

μ = μ pp + μ sc + μ ac , 𝜇 superscript 𝜇 pp superscript 𝜇 sc superscript 𝜇 ac \mu=\mu^{\mathrm{pp}}+\mu^{\mathrm{sc}}+\mu^{\mathrm{ac}}, italic_μ = italic_μ start_POSTSUPERSCRIPT roman_pp end_POSTSUPERSCRIPT + italic_μ start_POSTSUPERSCRIPT roman_sc end_POSTSUPERSCRIPT + italic_μ start_POSTSUPERSCRIPT roman_ac end_POSTSUPERSCRIPT , (2.1)

where μ pp superscript 𝜇 pp \mu^{\mathrm{pp}} italic_μ start_POSTSUPERSCRIPT roman_pp end_POSTSUPERSCRIPT , μ sc superscript 𝜇 sc \mu^{\mathrm{sc}} italic_μ start_POSTSUPERSCRIPT roman_sc end_POSTSUPERSCRIPT , and μ ac superscript 𝜇 ac \mu^{\mathrm{ac}} italic_μ start_POSTSUPERSCRIPT roman_ac end_POSTSUPERSCRIPT are the point mass, singular continuous, and absolutely continuous parts of μ 𝜇 \mu italic_μ , respectively.


Definition 2.2 (Moving Frame) .

Given a smooth left Lie group action G × M M normal-→ 𝐺 𝑀 𝑀 G\times M\rightarrow M italic_G × italic_M → italic_M , a moving frame on the domain 𝒰 M 𝒰 𝑀 \mathcal{U}\subset M caligraphic_U ⊂ italic_M is an equivariant map ρ : 𝒰 G normal-: 𝜌 normal-→ 𝒰 𝐺 \rho:\mathcal{U}\rightarrow G italic_ρ : caligraphic_U → italic_G , that is

ρ ( g z ) = g ρ ( z ) left equivariance ρ ( g z ) = ρ ( z ) g - 1 right equivariance 𝜌 𝑔 𝑧 𝑔 𝜌 𝑧 left equivariance 𝜌 𝑔 𝑧 𝜌 𝑧 superscript 𝑔 1 right equivariance \begin{array}[]{ll}\rho(g\cdot z)=g\rho(z)&\qquad\mbox{\emph{left equivariance% }}\\ \rho(g\cdot z)=\rho(z)g^{-1}&\qquad\mbox{\emph{right equivariance}}\end{array} start_ARRAY start_ROW start_CELL italic_ρ ( italic_g ⋅ italic_z ) = italic_g italic_ρ ( italic_z ) end_CELL start_CELL end_CELL end_ROW start_ROW start_CELL italic_ρ ( italic_g ⋅ italic_z ) = italic_ρ ( italic_z ) italic_g start_POSTSUPERSCRIPT - 1 end_POSTSUPERSCRIPT end_CELL start_CELL end_CELL end_ROW end_ARRAY

Definition 3

For a graph G = ( V , E ) 𝐺 𝑉 𝐸 G=(V,E) italic_G = ( italic_V , italic_E ) , let f ( k ) = | { v : d ( v ) k } | 𝑓 𝑘 conditional-set 𝑣 𝑑 𝑣 𝑘 f(k)=|\{v:d(v)\geq k\}| italic_f ( italic_k ) = | { italic_v : italic_d ( italic_v ) ≥ italic_k } | . The smooth ccdh of a graph G 𝐺 G italic_G is a function φ : 1 × [ 0 , 1 ) 0 : 𝜑 subscript absent 1 0 1 subscript absent 0 \varphi:\mathbb{Z}_{\geq 1}\times[0,1)\to\mathbb{R}_{\geq 0} italic_φ : blackboard_Z start_POSTSUBSCRIPT ≥ 1 end_POSTSUBSCRIPT × [ 0 , 1 ) → blackboard_R start_POSTSUBSCRIPT ≥ 0 end_POSTSUBSCRIPT defined by

φ ( x , ϵ ) = ( 1 - ϵ ) f ( x ) + ϵ f ( x + 1 ) . 𝜑 𝑥 italic-ϵ 1 italic-ϵ 𝑓 𝑥 italic-ϵ 𝑓 𝑥 1 \varphi(x,\epsilon)=(1-\epsilon)f(x)+\epsilon f(x+1). italic_φ ( italic_x , italic_ϵ ) = ( 1 - italic_ϵ ) italic_f ( italic_x ) + italic_ϵ italic_f ( italic_x + 1 ) .

For ease of notation, we may write φ ( x ) φ ( x , x - x ) 𝜑 𝑥 𝜑 𝑥 𝑥 𝑥 \varphi(x)\coloneqq\varphi(\lfloor x\rfloor,x-\lfloor x\rfloor) italic_φ ( italic_x ) ≔ italic_φ ( ⌊ italic_x ⌋ , italic_x - ⌊ italic_x ⌋ ) . {}_{\Box} start_FLOATSUBSCRIPT □ end_FLOATSUBSCRIPT


Definition 1.1

( [ 4 ] ) A BiHom-associative algebra is a 4-tuple ( A , μ , α , β ) 𝐴 𝜇 𝛼 𝛽 \left(A,\mu,\alpha,\beta\right) ( italic_A , italic_μ , italic_α , italic_β ) , where A 𝐴 A italic_A is a linear space and α , β : A A normal-: 𝛼 𝛽 normal-→ 𝐴 𝐴 \alpha,\beta:A\rightarrow A italic_α , italic_β : italic_A → italic_A and μ : A A A normal-: 𝜇 normal-→ tensor-product 𝐴 𝐴 𝐴 \mu:A\otimes A\rightarrow A italic_μ : italic_A ⊗ italic_A → italic_A are linear maps such that α β = β α 𝛼 𝛽 𝛽 𝛼 \alpha\circ\beta=\beta\circ\alpha italic_α ∘ italic_β = italic_β ∘ italic_α , α ( x y ) = α ( x ) α ( y ) 𝛼 normal-⋅ 𝑥 𝑦 normal-⋅ 𝛼 𝑥 𝛼 𝑦 \alpha(x\cdot y)=\alpha(x)\cdot\alpha(y) italic_α ( italic_x ⋅ italic_y ) = italic_α ( italic_x ) ⋅ italic_α ( italic_y ) , β ( x y ) = β ( x ) β ( y ) 𝛽 normal-⋅ 𝑥 𝑦 normal-⋅ 𝛽 𝑥 𝛽 𝑦 \beta(x\cdot y)=\beta(x)\cdot\beta(y) italic_β ( italic_x ⋅ italic_y ) = italic_β ( italic_x ) ⋅ italic_β ( italic_y ) and

α ( x ) ( y z ) = ( x y ) β ( z ) , 𝛼 𝑥 𝑦 𝑧 𝑥 𝑦 𝛽 𝑧 \displaystyle\alpha(x)\cdot(y\cdot z)=(x\cdot y)\cdot\beta(z), italic_α ( italic_x ) ⋅ ( italic_y ⋅ italic_z ) = ( italic_x ⋅ italic_y ) ⋅ italic_β ( italic_z ) , (1.1)

for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A . The maps α 𝛼 \alpha italic_α and β 𝛽 \beta italic_β (in this order) are called the structure maps of A 𝐴 A italic_A and condition ( 1.1 ) is called the BiHom-associativity condition.

A morphism f : ( A , μ A , α A , β A ) ( B , μ B , α B , β B ) normal-: 𝑓 normal-→ 𝐴 subscript 𝜇 𝐴 subscript 𝛼 𝐴 subscript 𝛽 𝐴 𝐵 subscript 𝜇 𝐵 subscript 𝛼 𝐵 subscript 𝛽 𝐵 f:(A,\mu_{A},\alpha_{A},\beta_{A})\rightarrow(B,\mu_{B},\alpha_{B},\beta_{B}) italic_f : ( italic_A , italic_μ start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , italic_α start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , italic_β start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT ) → ( italic_B , italic_μ start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT , italic_α start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT , italic_β start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ) of BiHom-associative algebras is a linear map f : A B normal-: 𝑓 normal-→ 𝐴 𝐵 f:A\rightarrow B italic_f : italic_A → italic_B such that α B f = f α A subscript 𝛼 𝐵 𝑓 𝑓 subscript 𝛼 𝐴 \alpha_{B}\circ f=f\circ\alpha_{A} italic_α start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ italic_f = italic_f ∘ italic_α start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , β B f = f β A subscript 𝛽 𝐵 𝑓 𝑓 subscript 𝛽 𝐴 \beta_{B}\circ f=f\circ\beta_{A} italic_β start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ italic_f = italic_f ∘ italic_β start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT and f μ A = μ B ( f f ) 𝑓 subscript 𝜇 𝐴 subscript 𝜇 𝐵 tensor-product 𝑓 𝑓 f\circ\mu_{A}=\mu_{B}\circ(f\otimes f) italic_f ∘ italic_μ start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT = italic_μ start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ ( italic_f ⊗ italic_f ) .

Definition 1.4

( [ 10 ] ) A left BiHom-pre-Lie algebra is a 4-tuple ( A , μ , α , β ) 𝐴 𝜇 𝛼 𝛽 (A,\mu,\alpha,\beta) ( italic_A , italic_μ , italic_α , italic_β ) , where A 𝐴 A italic_A is a linear space and μ : A A A normal-: 𝜇 normal-→ tensor-product 𝐴 𝐴 𝐴 \mu:A\otimes A\rightarrow A italic_μ : italic_A ⊗ italic_A → italic_A and α , β : A A normal-: 𝛼 𝛽 normal-→ 𝐴 𝐴 \alpha,\beta:A\rightarrow A italic_α , italic_β : italic_A → italic_A are linear maps satisfying α β = β α 𝛼 𝛽 𝛽 𝛼 \alpha\circ\beta=\beta\circ\alpha italic_α ∘ italic_β = italic_β ∘ italic_α , α ( x y ) = α ( x ) α ( y ) 𝛼 normal-⋅ 𝑥 𝑦 normal-⋅ 𝛼 𝑥 𝛼 𝑦 \alpha(x\cdot y)=\alpha(x)\cdot\alpha(y) italic_α ( italic_x ⋅ italic_y ) = italic_α ( italic_x ) ⋅ italic_α ( italic_y ) , β ( x y ) = β ( x ) β ( y ) 𝛽 normal-⋅ 𝑥 𝑦 normal-⋅ 𝛽 𝑥 𝛽 𝑦 \beta(x\cdot y)=\beta(x)\cdot\beta(y) italic_β ( italic_x ⋅ italic_y ) = italic_β ( italic_x ) ⋅ italic_β ( italic_y ) and

α β ( x ) ( α ( y ) z ) - ( β ( x ) α ( y ) ) β ( z ) = α β ( y ) ( α ( x ) z ) - ( β ( y ) α ( x ) ) β ( z ) , 𝛼 𝛽 𝑥 𝛼 𝑦 𝑧 𝛽 𝑥 𝛼 𝑦 𝛽 𝑧 𝛼 𝛽 𝑦 𝛼 𝑥 𝑧 𝛽 𝑦 𝛼 𝑥 𝛽 𝑧 \displaystyle\alpha\beta(x)\cdot(\alpha(y)\cdot z)-(\beta(x)\cdot\alpha(y))% \cdot\beta(z)=\alpha\beta(y)\cdot(\alpha(x)\cdot z)-(\beta(y)\cdot\alpha(x))% \cdot\beta(z), italic_α italic_β ( italic_x ) ⋅ ( italic_α ( italic_y ) ⋅ italic_z ) - ( italic_β ( italic_x ) ⋅ italic_α ( italic_y ) ) ⋅ italic_β ( italic_z ) = italic_α italic_β ( italic_y ) ⋅ ( italic_α ( italic_x ) ⋅ italic_z ) - ( italic_β ( italic_y ) ⋅ italic_α ( italic_x ) ) ⋅ italic_β ( italic_z ) , (1.3)

for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A . We call α 𝛼 \alpha italic_α and β 𝛽 \beta italic_β (in this order) the structure maps of A 𝐴 A italic_A .

A morphism f : ( A , μ , α , β ) ( A , μ , α , β ) normal-: 𝑓 normal-→ 𝐴 𝜇 𝛼 𝛽 superscript 𝐴 normal-′ superscript 𝜇 normal-′ superscript 𝛼 normal-′ superscript 𝛽 normal-′ f:(A,\mu,\alpha,\beta)\rightarrow(A^{\prime},\mu^{\prime},\alpha^{\prime},% \beta^{\prime}) italic_f : ( italic_A , italic_μ , italic_α , italic_β ) → ( italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_μ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_α start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) of left BiHom-pre-Lie algebras is a linear map f : A A normal-: 𝑓 normal-→ 𝐴 superscript 𝐴 normal-′ f:A\rightarrow A^{\prime} italic_f : italic_A → italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT satisfying f ( x y ) = f ( x ) f ( y ) 𝑓 normal-⋅ 𝑥 𝑦 superscript normal-⋅ normal-′ 𝑓 𝑥 𝑓 𝑦 f(x\cdot y)=f(x)\cdot^{\prime}f(y) italic_f ( italic_x ⋅ italic_y ) = italic_f ( italic_x ) ⋅ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT italic_f ( italic_y ) , for all x , y A 𝑥 𝑦 𝐴 x,y\in A italic_x , italic_y ∈ italic_A , as well as f α = α f 𝑓 𝛼 superscript 𝛼 normal-′ 𝑓 f\circ\alpha=\alpha^{\prime}\circ f italic_f ∘ italic_α = italic_α start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ∘ italic_f and f β = β f 𝑓 𝛽 superscript 𝛽 normal-′ 𝑓 f\circ\beta=\beta^{\prime}\circ f italic_f ∘ italic_β = italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ∘ italic_f .

Definition 1.5

( [ 10 ] ) A left (respectively right) BiHom-Leibniz algebra is a 4-tuple ( L , [ , ] , α , β ) 𝐿 normal-⋅ normal-⋅ 𝛼 𝛽 (L,[\cdot,\cdot],\alpha,\beta) ( italic_L , [ ⋅ , ⋅ ] , italic_α , italic_β ) , where L 𝐿 L italic_L is a linear space, [ , ] : L × L L normal-: normal-⋅ normal-⋅ normal-→ 𝐿 𝐿 𝐿 [\cdot,\cdot]:L\times L\rightarrow L [ ⋅ , ⋅ ] : italic_L × italic_L → italic_L is a bilinear map and α , β : L L normal-: 𝛼 𝛽 normal-→ 𝐿 𝐿 \alpha,\beta:L\rightarrow L italic_α , italic_β : italic_L → italic_L are linear maps satisfying α β = β α 𝛼 𝛽 𝛽 𝛼 \alpha\circ\beta=\beta\circ\alpha italic_α ∘ italic_β = italic_β ∘ italic_α , α ( [ x , y ] ) = [ α ( x ) , α ( y ) ] 𝛼 𝑥 𝑦 𝛼 𝑥 𝛼 𝑦 \alpha([x,y])=[\alpha(x),\alpha(y)] italic_α ( [ italic_x , italic_y ] ) = [ italic_α ( italic_x ) , italic_α ( italic_y ) ] , β ( [ x , y ] ) = [ β ( x ) , β ( y ) ] 𝛽 𝑥 𝑦 𝛽 𝑥 𝛽 𝑦 \beta([x,y])=[\beta(x),\beta(y)] italic_β ( [ italic_x , italic_y ] ) = [ italic_β ( italic_x ) , italic_β ( italic_y ) ] and

[ α β ( x ) , [ y , z ] ] = [ [ β ( x ) , y ] , β ( z ) ] + [ β ( y ) , [ α ( x ) , z ] ] , 𝛼 𝛽 𝑥 𝑦 𝑧 𝛽 𝑥 𝑦 𝛽 𝑧 𝛽 𝑦 𝛼 𝑥 𝑧 \displaystyle[\alpha\beta(x),[y,z]]=[[\beta(x),y],\beta(z)]+[\beta(y),[\alpha(% x),z]], [ italic_α italic_β ( italic_x ) , [ italic_y , italic_z ] ] = [ [ italic_β ( italic_x ) , italic_y ] , italic_β ( italic_z ) ] + [ italic_β ( italic_y ) , [ italic_α ( italic_x ) , italic_z ] ] , (1.4)

respectively

[ [ x , y ] , α β ( z ) ] = [ [ x , β ( z ) ] , α ( y ) ] + [ α ( x ) , [ y , α ( z ) ] ] , 𝑥 𝑦 𝛼 𝛽 𝑧 𝑥 𝛽 𝑧 𝛼 𝑦 𝛼 𝑥 𝑦 𝛼 𝑧 \displaystyle[[x,y],\alpha\beta(z)]=[[x,\beta(z)],\alpha(y)]+[\alpha(x),[y,% \alpha(z)]], [ [ italic_x , italic_y ] , italic_α italic_β ( italic_z ) ] = [ [ italic_x , italic_β ( italic_z ) ] , italic_α ( italic_y ) ] + [ italic_α ( italic_x ) , [ italic_y , italic_α ( italic_z ) ] ] , (1.5)

for all x , y , z L 𝑥 𝑦 𝑧 𝐿 x,y,z\in L italic_x , italic_y , italic_z ∈ italic_L . We call α 𝛼 \alpha italic_α and β 𝛽 \beta italic_β (in this order) the structure maps of L 𝐿 L italic_L .

Definition 1.7

( [ 9 ] ) A BiHom-dendriform algebra is a 5-tuple ( A , , , α , β ) 𝐴 precedes succeeds 𝛼 𝛽 (A,\prec,\succ,\alpha,\beta) ( italic_A , ≺ , ≻ , italic_α , italic_β ) consisting of a linear space A 𝐴 A italic_A and linear maps , : A A A fragments precedes normal-, succeeds normal-: A tensor-product A normal-→ A \prec,\succ:A\otimes A\rightarrow A ≺ , ≻ : italic_A ⊗ italic_A → italic_A and α , β : A A normal-: 𝛼 𝛽 normal-→ 𝐴 𝐴 \alpha,\beta:A\rightarrow A italic_α , italic_β : italic_A → italic_A such that, for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A :

α β = β α , 𝛼 𝛽 𝛽 𝛼 \displaystyle\alpha\circ\beta=\beta\circ\alpha, italic_α ∘ italic_β = italic_β ∘ italic_α , (1.7)
α ( x y ) = α ( x ) α ( y ) , α ( x y ) = α ( x ) α ( y ) , fragments α fragments ( x precedes y ) α fragments ( x ) precedes α fragments ( y ) , α fragments ( x succeeds y ) α fragments ( x ) succeeds α fragments ( y ) , \displaystyle\alpha(x\prec y)=\alpha(x)\prec\alpha(y),~{}\alpha(x\succ y)=% \alpha(x)\succ\alpha(y), italic_α ( italic_x ≺ italic_y ) = italic_α ( italic_x ) ≺ italic_α ( italic_y ) , italic_α ( italic_x ≻ italic_y ) = italic_α ( italic_x ) ≻ italic_α ( italic_y ) , (1.8)
β ( x y ) = β ( x ) β ( y ) , β ( x y ) = β ( x ) β ( y ) , fragments β fragments ( x precedes y ) β fragments ( x ) precedes β fragments ( y ) , β fragments ( x succeeds y ) β fragments ( x ) succeeds β fragments ( y ) , \displaystyle\beta(x\prec y)=\beta(x)\prec\beta(y),~{}\beta(x\succ y)=\beta(x)% \succ\beta(y), italic_β ( italic_x ≺ italic_y ) = italic_β ( italic_x ) ≺ italic_β ( italic_y ) , italic_β ( italic_x ≻ italic_y ) = italic_β ( italic_x ) ≻ italic_β ( italic_y ) , (1.9)
( x y ) β ( z ) = α ( x ) ( y z + y z ) , fragments fragments ( x precedes y ) precedes β fragments ( z ) α fragments ( x ) precedes fragments ( y precedes z y succeeds z ) , \displaystyle(x\prec y)\prec\beta(z)=\alpha(x)\prec(y\prec z+y\succ z), ( italic_x ≺ italic_y ) ≺ italic_β ( italic_z ) = italic_α ( italic_x ) ≺ ( italic_y ≺ italic_z + italic_y ≻ italic_z ) , (1.10)
( x y ) β ( z ) = α ( x ) ( y z ) , fragments fragments ( x succeeds y ) precedes β fragments ( z ) α fragments ( x ) succeeds fragments ( y precedes z ) , \displaystyle(x\succ y)\prec\beta(z)=\alpha(x)\succ(y\prec z), ( italic_x ≻ italic_y ) ≺ italic_β ( italic_z ) = italic_α ( italic_x ) ≻ ( italic_y ≺ italic_z ) , (1.11)
α ( x ) ( y z ) = ( x y + x y ) β ( z ) . fragments α fragments ( x ) succeeds fragments ( y succeeds z ) fragments ( x precedes y x succeeds y ) succeeds β fragments ( z ) . \displaystyle\alpha(x)\succ(y\succ z)=(x\prec y+x\succ y)\succ\beta(z). italic_α ( italic_x ) ≻ ( italic_y ≻ italic_z ) = ( italic_x ≺ italic_y + italic_x ≻ italic_y ) ≻ italic_β ( italic_z ) . (1.12)

We call α 𝛼 \alpha italic_α and β 𝛽 \beta italic_β (in this order) the structure maps of A 𝐴 A italic_A .

Definition 1.12

( [ 13 ] , [ 14 ] ) A Novikov-Poisson algebra is a triple ( A , , * ) 𝐴 normal-⋅ (A,\cdot,*) ( italic_A , ⋅ , * ) such that ( A , ) 𝐴 normal-⋅ (A,\cdot) ( italic_A , ⋅ ) is a commutative associative algebra, ( A , * ) 𝐴 (A,*) ( italic_A , * ) is a Novikov algebra and the following compatibility conditions hold, for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A :

( x * y ) z - x * ( y z ) = ( y * x ) z - y * ( x z ) , 𝑥 𝑦 𝑧 𝑥 𝑦 𝑧 𝑦 𝑥 𝑧 𝑦 𝑥 𝑧 \displaystyle(x*y)\cdot z-x*(y\cdot z)=(y*x)\cdot z-y*(x\cdot z), ( italic_x * italic_y ) ⋅ italic_z - italic_x * ( italic_y ⋅ italic_z ) = ( italic_y * italic_x ) ⋅ italic_z - italic_y * ( italic_x ⋅ italic_z ) , (1.17)
( x y ) * z = ( x * z ) y . 𝑥 𝑦 𝑧 𝑥 𝑧 𝑦 \displaystyle(x\cdot y)*z=(x*z)\cdot y. ( italic_x ⋅ italic_y ) * italic_z = ( italic_x * italic_z ) ⋅ italic_y . (1.18)

A morphism of Novikov-Poisson algebras from ( A , , * ) 𝐴 normal-⋅ (A,\cdot,*) ( italic_A , ⋅ , * ) to ( A , , * ) superscript 𝐴 normal-′ superscript normal-⋅ normal-′ superscript normal-′ (A^{\prime},\cdot^{\prime},*^{\prime}) ( italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , ⋅ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , * start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) is a linear map f : A A normal-: 𝑓 normal-→ 𝐴 superscript 𝐴 normal-′ f:A\rightarrow A^{\prime} italic_f : italic_A → italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT satisfying f ( x y ) = f ( x ) f ( y ) 𝑓 normal-⋅ 𝑥 𝑦 superscript normal-⋅ normal-′ 𝑓 𝑥 𝑓 𝑦 f(x\cdot y)=f(x)\cdot^{\prime}f(y) italic_f ( italic_x ⋅ italic_y ) = italic_f ( italic_x ) ⋅ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT italic_f ( italic_y ) and f ( x * y ) = f ( x ) * f ( y ) 𝑓 𝑥 𝑦 superscript normal-′ 𝑓 𝑥 𝑓 𝑦 f(x*y)=f(x)*^{\prime}f(y) italic_f ( italic_x * italic_y ) = italic_f ( italic_x ) * start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT italic_f ( italic_y ) , for all x , y A 𝑥 𝑦 𝐴 x,y\in A italic_x , italic_y ∈ italic_A .

Definition 2.1

A BiHom-Novikov algebra is a 4-tuple ( A , μ , α , β ) 𝐴 𝜇 𝛼 𝛽 (A,\mu,\alpha,\beta) ( italic_A , italic_μ , italic_α , italic_β ) , where A 𝐴 A italic_A is a linear space, μ : A A A normal-: 𝜇 normal-→ tensor-product 𝐴 𝐴 𝐴 \mu:A\otimes A\rightarrow A italic_μ : italic_A ⊗ italic_A → italic_A is a linear map and α , β : A A normal-: 𝛼 𝛽 normal-→ 𝐴 𝐴 \alpha,\beta:A\rightarrow A italic_α , italic_β : italic_A → italic_A are commuting linear maps (called the structure maps of A 𝐴 A italic_A ), satisfying the following conditions, for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A :

α ( x y ) = α ( x ) α ( y ) , β ( x y ) = β ( x ) β ( y ) , formulae-sequence 𝛼 𝑥 𝑦 𝛼 𝑥 𝛼 𝑦 𝛽 𝑥 𝑦 𝛽 𝑥 𝛽 𝑦 \displaystyle\alpha(x\cdot y)=\alpha(x)\cdot\alpha(y),~{}~{}\beta(x\cdot y)=% \beta(x)\cdot\beta(y), italic_α ( italic_x ⋅ italic_y ) = italic_α ( italic_x ) ⋅ italic_α ( italic_y ) , italic_β ( italic_x ⋅ italic_y ) = italic_β ( italic_x ) ⋅ italic_β ( italic_y ) , (2.1)
( β ( x ) α ( y ) ) β ( z ) - α β ( x ) ( α ( y ) z ) = ( β ( y ) α ( x ) ) β ( z ) - α β ( y ) ( α ( x ) z ) , 𝛽 𝑥 𝛼 𝑦 𝛽 𝑧 𝛼 𝛽 𝑥 𝛼 𝑦 𝑧 𝛽 𝑦 𝛼 𝑥 𝛽 𝑧 𝛼 𝛽 𝑦 𝛼 𝑥 𝑧 \displaystyle(\beta(x)\cdot\alpha(y))\cdot\beta(z)-\alpha\beta(x)\cdot(\alpha(% y)\cdot z)=(\beta(y)\cdot\alpha(x))\cdot\beta(z)-\alpha\beta(y)\cdot(\alpha(x)% \cdot z), ( italic_β ( italic_x ) ⋅ italic_α ( italic_y ) ) ⋅ italic_β ( italic_z ) - italic_α italic_β ( italic_x ) ⋅ ( italic_α ( italic_y ) ⋅ italic_z ) = ( italic_β ( italic_y ) ⋅ italic_α ( italic_x ) ) ⋅ italic_β ( italic_z ) - italic_α italic_β ( italic_y ) ⋅ ( italic_α ( italic_x ) ⋅ italic_z ) , (2.2)
( x β ( y ) ) α β ( z ) = ( x β ( z ) ) α β ( y ) . 𝑥 𝛽 𝑦 𝛼 𝛽 𝑧 𝑥 𝛽 𝑧 𝛼 𝛽 𝑦 \displaystyle(x\cdot\beta(y))\cdot\alpha\beta(z)=(x\cdot\beta(z))\cdot\alpha% \beta(y). ( italic_x ⋅ italic_β ( italic_y ) ) ⋅ italic_α italic_β ( italic_z ) = ( italic_x ⋅ italic_β ( italic_z ) ) ⋅ italic_α italic_β ( italic_y ) . (2.3)

In other words, a BiHom-Novikov algebra is a left BiHom-pre-Lie algebra satisfying ( 2.3 ).

A morphism f : ( A , μ A , α A , β A ) ( B , μ B , α B , β B ) normal-: 𝑓 normal-→ 𝐴 subscript 𝜇 𝐴 subscript 𝛼 𝐴 subscript 𝛽 𝐴 𝐵 subscript 𝜇 𝐵 subscript 𝛼 𝐵 subscript 𝛽 𝐵 f:(A,\mu_{A},\alpha_{A},\beta_{A})\rightarrow(B,\mu_{B},\alpha_{B},\beta_{B}) italic_f : ( italic_A , italic_μ start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , italic_α start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , italic_β start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT ) → ( italic_B , italic_μ start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT , italic_α start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT , italic_β start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ) of BiHom-Novikov algebras is a linear map f : A B normal-: 𝑓 normal-→ 𝐴 𝐵 f:A\rightarrow B italic_f : italic_A → italic_B such that α B f = f α A subscript 𝛼 𝐵 𝑓 𝑓 subscript 𝛼 𝐴 \alpha_{B}\circ f=f\circ\alpha_{A} italic_α start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ italic_f = italic_f ∘ italic_α start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT , β B f = f β A subscript 𝛽 𝐵 𝑓 𝑓 subscript 𝛽 𝐴 \beta_{B}\circ f=f\circ\beta_{A} italic_β start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ italic_f = italic_f ∘ italic_β start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT and f μ A = μ B ( f f ) 𝑓 subscript 𝜇 𝐴 subscript 𝜇 𝐵 tensor-product 𝑓 𝑓 f\circ\mu_{A}=\mu_{B}\circ(f\otimes f) italic_f ∘ italic_μ start_POSTSUBSCRIPT italic_A end_POSTSUBSCRIPT = italic_μ start_POSTSUBSCRIPT italic_B end_POSTSUBSCRIPT ∘ ( italic_f ⊗ italic_f ) .

Definition 3.1

A BiHom-Novikov-Poisson algebra is a 5-tuple ( A , , , α , β ) 𝐴 normal-⋅ normal-∗ 𝛼 𝛽 (A,\cdot,\ast,\alpha,\beta) ( italic_A , ⋅ , ∗ , italic_α , italic_β ) such that:

(1) ( A , , α , β ) 𝐴 normal-⋅ 𝛼 𝛽 (A,\cdot,\alpha,\beta) ( italic_A , ⋅ , italic_α , italic_β ) is a BiHom-commutative algebra;

(2) ( A , , α , β ) 𝐴 normal-∗ 𝛼 𝛽 (A,\ast,\alpha,\beta) ( italic_A , ∗ , italic_α , italic_β ) is a BiHom-Novikov algebra;

(3) the following compatibility conditions hold for all x , y , z A 𝑥 𝑦 𝑧 𝐴 x,y,z\in A italic_x , italic_y , italic_z ∈ italic_A :

( β ( x ) α ( y ) ) β ( z ) - α β ( x ) ( α ( y ) z ) = ( β ( y ) α ( x ) ) β ( z ) - α β ( y ) ( α ( x ) z ) , 𝛽 𝑥 𝛼 𝑦 𝛽 𝑧 𝛼 𝛽 𝑥 𝛼 𝑦 𝑧 𝛽 𝑦 𝛼 𝑥 𝛽 𝑧 𝛼 𝛽 𝑦 𝛼 𝑥 𝑧 \displaystyle(\beta(x)\ast\alpha(y))\cdot\beta(z)-\alpha\beta(x)\ast(\alpha(y)% \cdot z)=(\beta(y)\ast\alpha(x))\cdot\beta(z)-\alpha\beta(y)\ast(\alpha(x)% \cdot z), ( italic_β ( italic_x ) ∗ italic_α ( italic_y ) ) ⋅ italic_β ( italic_z ) - italic_α italic_β ( italic_x ) ∗ ( italic_α ( italic_y ) ⋅ italic_z ) = ( italic_β ( italic_y ) ∗ italic_α ( italic_x ) ) ⋅ italic_β ( italic_z ) - italic_α italic_β ( italic_y ) ∗ ( italic_α ( italic_x ) ⋅ italic_z ) , (3.1)
( x β ( y ) ) α β ( z ) = ( x β ( z ) ) α β ( y ) = α ( x ) ( β ( y ) α ( z ) ) . 𝑥 𝛽 𝑦 𝛼 𝛽 𝑧 𝑥 𝛽 𝑧 𝛼 𝛽 𝑦 𝛼 𝑥 𝛽 𝑦 𝛼 𝑧 \displaystyle(x\cdot\beta(y))\ast\alpha\beta(z)=(x\ast\beta(z))\cdot\alpha% \beta(y)=\alpha(x)\cdot(\beta(y)\ast\alpha(z)). ( italic_x ⋅ italic_β ( italic_y ) ) ∗ italic_α italic_β ( italic_z ) = ( italic_x ∗ italic_β ( italic_z ) ) ⋅ italic_α italic_β ( italic_y ) = italic_α ( italic_x ) ⋅ ( italic_β ( italic_y ) ∗ italic_α ( italic_z ) ) . (3.2)

The maps α 𝛼 \alpha italic_α and β 𝛽 \beta italic_β (in this order) are called the structure maps of A 𝐴 A italic_A .

A morphism f : ( A , , , α , β ) ( A , , , α , β ) normal-: 𝑓 normal-→ 𝐴 normal-⋅ normal-∗ 𝛼 𝛽 superscript 𝐴 normal-′ superscript normal-⋅ normal-′ superscript normal-∗ normal-′ superscript 𝛼 normal-′ superscript 𝛽 normal-′ f:(A,\cdot,\ast,\alpha,\beta)\rightarrow(A^{\prime},\cdot^{\prime},\ast^{% \prime},\alpha^{\prime},\beta^{\prime}) italic_f : ( italic_A , ⋅ , ∗ , italic_α , italic_β ) → ( italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , ⋅ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , ∗ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_α start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) of BiHom-Novikov-Poisson algebras is a map that is a morphism of BiHom-associative algebras from ( A , , α , β ) 𝐴 normal-⋅ 𝛼 𝛽 (A,\cdot,\alpha,\beta) ( italic_A , ⋅ , italic_α , italic_β ) to ( A , , α , β ) superscript 𝐴 normal-′ superscript normal-⋅ normal-′ superscript 𝛼 normal-′ superscript 𝛽 normal-′ (A^{\prime},\cdot^{\prime},\alpha^{\prime},\beta^{\prime}) ( italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , ⋅ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_α start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) and a morphism of BiHom-Novikov algebras from ( A , , α , β ) 𝐴 normal-∗ 𝛼 𝛽 (A,\ast,\alpha,\beta) ( italic_A , ∗ , italic_α , italic_β ) to ( A , , α , β ) superscript 𝐴 normal-′ superscript normal-∗ normal-′ superscript 𝛼 normal-′ superscript 𝛽 normal-′ (A^{\prime},\ast^{\prime},\alpha^{\prime},\beta^{\prime}) ( italic_A start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , ∗ start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_α start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT , italic_β start_POSTSUPERSCRIPT ′ end_POSTSUPERSCRIPT ) .


Definition 1 .

The steady-state input-output relation k 𝑘 k italic_k of a dynamical system is the collection of all steady-state input-output pairs of the system. Given a steady-state input u normal-u \mathrm{u} roman_u and a steady-state y normal-y \mathrm{y} roman_y , we define

k ( u ) = { y : ( u , y ) k } and k - 1 ( y ) = { u : ( u , y ) k } . 𝑘 u conditional-set y u y 𝑘 and superscript 𝑘 1 y conditional-set u u y 𝑘 \displaystyle k(\mathrm{u})=\{\mathrm{y}:\ (\mathrm{u,y})\in k\}\text{ and }\;% k^{-1}(\mathrm{y})=\{\mathrm{u}:\ (\mathrm{u,y})\in k\}. italic_k ( roman_u ) = { roman_y : ( roman_u , roman_y ) ∈ italic_k } and italic_k start_POSTSUPERSCRIPT - 1 end_POSTSUPERSCRIPT ( roman_y ) = { roman_u : ( roman_u , roman_y ) ∈ italic_k } .

Definition 6.2 .

For w 1 , r 2 formulae-sequence 𝑤 1 𝑟 2 w\geq 1,r\geq 2 italic_w ≥ 1 , italic_r ≥ 2 define

α ( w , r ) = sup { κ : κ -regular w -set system without r pairwise disjoint sets } . 𝛼 𝑤 𝑟 supremum conditional-set 𝜅 𝜅 -regular 𝑤 -set system without 𝑟 pairwise disjoint sets \alpha(w,r)=\sup\{\kappa:\exists\kappa\text{-regular }w\text{-set system % without }r\text{ pairwise disjoint sets}\}. italic_α ( italic_w , italic_r ) = roman_sup { italic_κ : ∃ italic_κ -regular italic_w -set system without italic_r pairwise disjoint sets } .

It will be convenient to shorthand β ( w ) = α ( w , 2 ) 𝛽 𝑤 𝛼 𝑤 2 \beta(w)=\alpha(w,2) italic_β ( italic_w ) = italic_α ( italic_w , 2 ) , which can equivalently be defined as

β ( w ) = sup { κ : κ -regular intersecting w -set system } . 𝛽 𝑤 supremum conditional-set 𝜅 𝜅 -regular intersecting 𝑤 -set system \beta(w)=\sup\{\kappa:\exists\kappa\text{-regular intersecting }w\text{-set % system}\}. italic_β ( italic_w ) = roman_sup { italic_κ : ∃ italic_κ -regular intersecting italic_w -set system } .

Definition 5.2 .

An algebra ( 𝔞 , * ) 𝔞 (\mathfrak{a},*) ( fraktur_a , * ) is called left-symmetric if the following identity holds:

ξ * ( η * ζ ) - ( ξ * η ) * ζ = η * ( ξ * ζ ) - ( η * ξ ) * ζ , for all ξ , η , ζ 𝔞 . formulae-sequence 𝜉 𝜂 𝜁 𝜉 𝜂 𝜁 𝜂 𝜉 𝜁 𝜂 𝜉 𝜁 for all 𝜉 𝜂 𝜁 𝔞 \xi*(\eta*\zeta)-(\xi*\eta)*\zeta=\eta*(\xi*\zeta)-(\eta*\xi)*\zeta,\quad\mbox% {for all }\xi,\eta,\zeta\in\mathfrak{a}. italic_ξ * ( italic_η * italic_ζ ) - ( italic_ξ * italic_η ) * italic_ζ = italic_η * ( italic_ξ * italic_ζ ) - ( italic_η * italic_ξ ) * italic_ζ , for all italic_ξ , italic_η , italic_ζ ∈ fraktur_a . (24)

Definition 1

Let X 𝑋 X italic_X be an open subset of k superscript 𝑘 \mathbb{R}^{k} blackboard_R start_POSTSUPERSCRIPT italic_k end_POSTSUPERSCRIPT , k 1 𝑘 1 k\geq 1 italic_k ≥ 1 . A system

x ˙ ( t ) = f ( t , x ( t ) ) ˙ 𝑥 𝑡 𝑓 𝑡 𝑥 𝑡 \dot{x}(t)=f(t,x(t)) ˙ start_ARG italic_x end_ARG ( italic_t ) = italic_f ( italic_t , italic_x ( italic_t ) ) (23)

with x ( t ) X 𝑥 𝑡 𝑋 x(t)\in X italic_x ( italic_t ) ∈ italic_X is called a quasi-autonomous system with limiting system

y ˙ ( t ) = g ( y ( t ) ) ˙ 𝑦 𝑡 𝑔 𝑦 𝑡 \dot{y}(t)=g(y(t)) ˙ start_ARG italic_y end_ARG ( italic_t ) = italic_g ( italic_y ( italic_t ) ) (24)

if for any compact set K X 𝐾 𝑋 K\subset X italic_K ⊂ italic_X

t 0 sup x ( t ) K || f ( t , x ( t ) ) - g ( x ( t ) ) || d t < . superscript subscript subscript 𝑡 0 subscript supremum 𝑥 𝑡 𝐾 norm 𝑓 𝑡 𝑥 𝑡 𝑔 𝑥 𝑡 𝑑 𝑡 \int_{t_{0}}^{\infty}\sup_{x(t)\in K}||f(t,x(t))-g(x(t))||dt<\infty. ∫ start_POSTSUBSCRIPT italic_t start_POSTSUBSCRIPT 0 end_POSTSUBSCRIPT end_POSTSUBSCRIPT start_POSTSUPERSCRIPT ∞ end_POSTSUPERSCRIPT roman_sup start_POSTSUBSCRIPT italic_x ( italic_t ) ∈ italic_K end_POSTSUBSCRIPT | | italic_f ( italic_t , italic_x ( italic_t ) ) - italic_g ( italic_x ( italic_t ) ) | | italic_d italic_t < ∞ . (25)

{}_{\Box} start_FLOATSUBSCRIPT □ end_FLOATSUBSCRIPT


Definition 1.1 .

Let f : N : 𝑓 𝑁 f:\mathcal{R}\to N italic_f : caligraphic_R → italic_N be a map from a Riemann surface \mathcal{R} caligraphic_R into a Riemannian manifold N 𝑁 N italic_N . Moreover, let γ 𝛾 \gamma italic_γ and ρ 𝜌 \rho italic_ρ be elements of Aut ( ) Aut \operatorname{Aut}(\mathcal{R}) roman_Aut ( caligraphic_R ) and Iso ( N ) Iso 𝑁 \operatorname{Iso}(N) roman_Iso ( italic_N ) , respectively. Then f 𝑓 f italic_f is symmetric with respect to ( γ , ρ ) Aut ( ) × Iso ( N ) 𝛾 𝜌 normal-Aut normal-Iso 𝑁 (\gamma,\rho)\in\operatorname{Aut}(\mathcal{R})\times\operatorname{Iso}(N) ( italic_γ , italic_ρ ) ∈ roman_Aut ( caligraphic_R ) × roman_Iso ( italic_N ) if

(1.1) f γ = ρ f 𝑓 𝛾 𝜌 𝑓 f\circ\gamma=\rho\circ f italic_f ∘ italic_γ = italic_ρ ∘ italic_f

holds.


Definition 6 .

A stochastic product on 𝒮 ( ) 𝒮 \mathcal{S}(\mathcal{H}) caligraphic_S ( caligraphic_H ) is a map ( ) ( ) : 𝒮 ( ) × 𝒮 ( ) 𝒮 ( ) : direct-product 𝒮 𝒮 𝒮 (\hskip 0.853583pt\cdot\hskip 0.853583pt)\odot(\hskip 0.853583pt\cdot\hskip 0.% 853583pt)\colon\mathcal{S}(\mathcal{H})\times\mathcal{S}(\mathcal{H})% \rightarrow\mathcal{S}(\mathcal{H}) ( ⋅ ) ⊙ ( ⋅ ) : caligraphic_S ( caligraphic_H ) × caligraphic_S ( caligraphic_H ) → caligraphic_S ( caligraphic_H ) that is convex-linear in both its arguments, i.e.,

( α ρ + ( 1 - α ) σ ) ( ϵ τ + ( 1 - ϵ ) υ ) = α ϵ ρ τ + α ( 1 - ϵ ) ρ υ + ( 1 - α ) ϵ σ τ + ( 1 - α ) ( 1 - ϵ ) σ υ , direct-product 𝛼 𝜌 1 𝛼 𝜎 italic-ϵ 𝜏 1 italic-ϵ 𝜐 direct-product 𝛼 italic-ϵ 𝜌 𝜏 direct-product 𝛼 1 italic-ϵ 𝜌 𝜐 direct-product 1 𝛼 italic-ϵ 𝜎 𝜏 direct-product 1 𝛼 1 italic-ϵ 𝜎 𝜐 (\alpha\hskip 0.853583pt\rho+(1-\alpha)\sigma)\odot(\epsilon\tau+(1-\epsilon)% \upsilon)=\alpha\hskip 0.853583pt\epsilon\hskip 1.707165pt\rho\odot\tau+\alpha% (1-\epsilon)\hskip 1.707165pt\rho\odot\upsilon+(1-\alpha)\epsilon\hskip 1.7071% 65pt\sigma\odot\tau+(1-\alpha)(1-\epsilon)\hskip 1.707165pt\sigma\odot\upsilon% \hskip 0.853583pt, ( italic_α italic_ρ + ( 1 - italic_α ) italic_σ ) ⊙ ( italic_ϵ italic_τ + ( 1 - italic_ϵ ) italic_υ ) = italic_α italic_ϵ italic_ρ ⊙ italic_τ + italic_α ( 1 - italic_ϵ ) italic_ρ ⊙ italic_υ + ( 1 - italic_α ) italic_ϵ italic_σ ⊙ italic_τ + ( 1 - italic_α ) ( 1 - italic_ϵ ) italic_σ ⊙ italic_υ , (34)

for all ρ , σ , τ , υ 𝒮 ( ) 𝜌 𝜎 𝜏 𝜐 𝒮 \rho,\sigma,\tau,\upsilon\in\mathcal{S}(\mathcal{H}) italic_ρ , italic_σ , italic_τ , italic_υ ∈ caligraphic_S ( caligraphic_H ) and α , ϵ [ 0 , 1 ] 𝛼 italic-ϵ 0 1 \alpha,\epsilon\in[0,1] italic_α , italic_ϵ ∈ [ 0 , 1 ] .