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Topic: computer as state machine
topics >
computer science >
computer hardware >
Petri net
Topic:
problems with the von Neumann architecture
Topic:
rules
Topic:
state
Topic:
state machine
Topic:
Turing machine
Topic:
von Neumann computer
Topic:
what is a computer
Summary
A computer is a state machine, or more accurately, behaves as if it were a state machine. Most circuitry is binary. Early computers experimented with decimal and other bases. The idea of state is an abstract interpretation of analog processes.A state machine is a direct implementation of a Turing machine, and is thus a universal model for programming. While usually too cumbersome as an execution model for large programs, it is an accurate picture of the static description of a program.
This distinction between the computer's behavior and our interpretation of that behavior is an important one. What makes a computer isn't its behavior. What makes a computer is an observer-defined interpretation of how that behavior correlates to numbers and how those numbers correlate to rules, real events and objects. (cbb 4/94)
Subtopic: state machine
Quote: digital computers use relay-like elements of two or more states; e.g., neurons which can be imitated by vacuum tubes at 1000x faster [»vonnJ6_1945] Quote: a computer's arithmetic, control and memory parts should use binary representation; simpler logical structure [»vonnJ6_1945] Quote: a computing machine is an automatic machine that uses 0 and 1 for input and output [»turiAM11_1936]
Subtopic: program and data as initial state
Quote: a program determines a set of executions, i.e., a sequence of states [»parnDL_1997] Quote: a true, digital computer is an abstraction; a real computer must be composed of analogue circuits [»wilkVW8_1992] Quote: discrete state machines move from state to state; don't really exist but still a useful abstraction [»turiAM10_1950] Quote: a digital device is always in some state; so states partition its existential time and transitions are instantaneous [»holtAW11_1980] Quote: a computer hardware designer simulates discrete behavior by analog means Quote: an 'and' gate only works correctly if its inputs do not change; not physically realizable because of missing reaction [»petrCA1_1966, OK] Quote: the physical state of a computer does not describe the computational process; a computational state is an equivalence class of complex physical states [»pylyZW_1986]
Subtopic: observer-relative
Quote: a program defines the initial conditions of a computer or state machine [»cbb_1973, OK] Quote: a data object is a number since it is part of the initial state of a computation Quote: in a digital device, changing a single bit can have drastic consequences; a radical novelty of computers [»dijkEW12_1989]
Quote: computation and syntax are observer-relative; 0/1 depends on an interpretation [»searJR_1992] Quote: computers only operate on the marks of numbers; humans set up a correspondence between any set of things and numbers [»jakiSL_1969] Quote: digital computers allow many representational layers; a variable may represent a satellite and in turn be represented by a voltage [»winoT_1986] Quote: most computational theories of mind assume a homunculus; even if reduce to 0/1's still need a homunculus to interpret them [»searJR_1992] Quote: cognitive science can never be a natural science since computation is observer-relative Quote: representation is in the mind of the beholder; nothing in the computer or program depends on the representation selected [»winoT_1986] Quote: a mechanical computer does not literally follow rules; it only behaves as if it does
[»searJR_1992]
Topic: Petri net (44 items)
Topic: problems with the von Neumann architecture (11 items)
Topic: rules (43 items)
Topic: state (35 items)
Topic: state machine (67 items)
Topic: Turing machine (30 items)
Topic: von Neumann computer (14 items)
Topic: what is a computer
(62 items)