20/05/11 17:39:42 zmgc47N7.net
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つづき
(iii) Again in the context of mutation-histories such as the one given in the final display of (i), although one may, on certain occasions, wish to apply various
mutations that fundamentally alter the structure of the mathematical objects involved and hence give rise to “output species-objects” of the “S” on the right that
are related in a highly nontrivial fashion to the “input species-objects” of the “S”on the left, it is also of interest to consider
“portions” of the various mathematical objects that occur that are left unaltered by the various mutations that one applies.
This is precisely the reason for the introduction of the notion of a core of a mutationhistory. One important consequence of the construction of various cores associated to a mutation-history is that often
one may apply various cores associated to a mutation-history to describe,
by means of non-coric observables, the portions of the various mathematical objects that occur which are altered by the various mutations that one applies in terms of the unaltered portions, i.e., cores.
Indeed, this point of view plays a central role in the theory of the present series of
papers - cf. the discussion of Remark 3.6.1, (ii), below.
(引用終り)
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