Infinite structures such as streams and infinite trees can be characterized as final coalgebras. Also, stream processors can be described by a final coalgebra. In this talk, we introduce coalgebras as state transition systems and observe the power of final coalgebras. Then we explain the relation between stream processors and coalgebras. If we can, we see the relation to comodels of algebraic theories.

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In Student Colloquium, we do not fix the end time. Though a nominal time is shown above, we mean neither that it will be so, nor that it was so.