question on relativization of an algorithm




Hello,

I was reading Lance Fortnow's paper on relativization and I hit a bit
of a snag as far as my understanding goes.

"It is a misnomer to relativize a complexity class C. Instead,
suppose we take an enumeration of machines for C and give them some
access mechanism to an oracle set A. We then say the relativized
class C^A consists of the languages recognized by the acceptance
criteria for C applied to the machines using the oracle A."

What I don't understand is what exactly the "result" is when we
relativize an algorithm. If I have an algorithm, say one that decides
the language DIVISIBLEBYFOUR, and give it access to a SAT oracle, what
is the result? Is it a single machine? Is it a language associated
with a machine? Or is it several machines? I'm quite confused.

Any help anyone could provide would be appreciated.

-Phil
.



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