All computers are analog at their base. The only thing that distinguishes so-called analog computers from typical computers is their lack of universality. The analogies/models these analog computers implement are simply more obvious than those of the more universal, general purpose, computers. Universality is proportional to the extent to which the computation is purely syntactical (non-semantic). The less universal, the more specific, the more "analog".
The false identification of continuity with "analog" and discreteness with "digital" is a red herring and has caused all sorts of nonsensical hot air. What's important is how the machine models its referent. Analog computers (like the MOSFET √ Marcus linked to) simply have a natural and tightly bound referent. It's that tight _binding_ that gives the analog computers both their efficiency edge and their lack of universality. The meaning has already been assigned (or at least constrained). Analog computers are implementations of domain-specific languages. On 07/06/2016 02:31 PM, Robert J. Cordingley wrote: > My question is then what do Analog Computers > <https://en.wikipedia.org/wiki/Analog_computer> do and how do they fit into > Nick's exploration? As I recall they have no procedures but do produce > 'answers' without computation as we commonly know it these days. They > probably have an 'accept state' to tell the user when the 'answer' is > available. The same Wikipedia article (linked) speaks to ongoing research > into their use. -- glen ep ropella ⊥ 971-280-5699 ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College to unsubscribe http://redfish.com/mailman/listinfo/friam_redfish.com
