Problem
Many different physical systems can approximate the passage of time at different intervals. At the computational level of explanation, we could analyze this task in its more general form: any physical system will take the passage of time as input and output a measurment of the duration (either in discrete or continuous terms). General constraints that hold for all physical systems that perform this computation are that they have limited memory capacity. Provide two disntict descriptions of algorithms that can perform this computation. For each algorithm, provide an example of how it could be physically implemented.