−Table of Contents
Generalized effect algebras
Abbreviation: GEAlg
Definition
A \emph{generalized effect algebra} is a separation algebra that is
\emph{positive}: x⋅y=e implies x=e=y.
Definition
A \emph{generalized effect algebra} is of the form ⟨A,+,0⟩ where +:A2→A∪{∗} is a partial operation such that
+ is \emph{commutative}: x+y≠∗ implies x+y=y+x
+ is \emph{associative}: x+y≠∗ implies (x+y)+z=x+(y+z)
0 is an \emph{identity}: x+0=x
+ is \emph{cancellative}: x+y=x+z implies y=z and
+ is \emph{positive}: x+y=0 implies x=0.
Morphisms
Let A and B be generalized effect algebra. A morphism from A to B is a function h:A→B that is a homomorphism: h(e)=e and if x+y≠∗ then h(x+y)=h(x)+h(y).
Examples
Example 1:
Basic results
Properties
Finite members
$\begin{array}{lr}
f(1)= &1\\ f(2)= &1\\ f(3)= &2\\ f(4)= &5\\ f(5)= &12\\ f(6)= &35\\ f(7)= &119\\ f(8)= &496\\ f(9)= &2699\\ f(10)= &21888\\ f(11)= &292496\\
\end{array}$