# Chemical concrete machine, detailed (IV)

As a preparation for the Turing computation properties of the chemical concrete machine, in this post I shall explain what multipliers and co-multipliers are.

Basically,  multipliers and co-multipliers are molecules which self-multiply.  More precisely, in the next figure we see the definition of those:

Here $A$  and $A'$ are molecules from the formalism of the chemical concrete machine and $1$ and $2$ are labels. The blue arrow means any chemical reaction which is allowed.

Question: by close examination of the previous posts on graphic lambda calculus, can you identify any multiplier? or co-multiplier?

If not, then be patient, because in a future post I shall give plenty examples of those, especially connected with logic.

Further, we shall see that $\beta$ zippers, introduced in Chemical concret machine, detailed (III) , multiply in a very graphic way, kind of like what happens with the DNA of a cell when it divides. Let’s see.

We want to know if a zipper can be a multiplier. In the following figure we see what happens in the presence of DIST enzymes:

The reaction continues:

Now, the zipper multiplied into two zippers, but they are still connected.  We need more information about $A, B, C, D$ and $A', B', C', D'$.   Remark that:

In conclusion: if $A, B, C, D$ are multipliers and $A', B', C', D'$ are co-multipliers, then the zipper is a multiplier!

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