Adaptive logspace reducibility and parallel time

  title={Adaptive logspace reducibility and parallel time},
  author={Carme {\`A}lvarez and Jos{\'e} Lu{\'i}s Balc{\'a}zar and Birgit Jenner},
  journal={Mathematical systems theory},
We discuss two notions of functional oracle for logarithmic space-bounded machines, which differ in whether there is only one oracle tape for both the query and the answer or a separate tape for the answer, which can still be read while the next query is already being constructed. The first notion turns out to be basically nonadaptive, behaving like access to an oracle set. The second notion, on the other hand, is adaptive. By imposing appropriate bounds on the number of functional oracle… 
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