Hyperstructure Explained

Hyperstructures are algebraic structures equipped with at least one multi-valued operation, called a hyperoperation. The largest classes of the hyperstructures are the ones called

Hv

– structures.

A hyperoperation

(\star)

on a nonempty set

H

is a mapping from

H x H

to the nonempty power set

P*(H)

, meaning the set of all nonempty subsets of

H

, i.e.

\star:H x H\toP*(H)

   (x,y)\mapstox\stary\subseteqH.

For

A,B\subseteqH

we define

A\starB=cupaa\starb

and

A\starx=A\star\{x\},

x\starB=\{x\}\starB.

(H,\star)

is a semihypergroup if

(\star)

is an associative hyperoperation, i.e.

x\star(y\starz)=(x\stary)\starz

for all

x,y,z\inH.

Furthermore, a hypergroup is a semihypergroup

(H,\star)

, where the reproduction axiom is valid, i.e.

a\starH=H\stara=H

for all

a\inH.

References