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Philosophical Papers --- Date Unknown Does the Universe do Calculations (Is the Physical Universe a Calculator or a Computer)? The question was "does the universe do computations," which I take to be basically the same question as to "whether nature is a computer." Both nature and computers are mechanisms. But the question is whether they are the same type of mechanism. Not all mechanisms are computers. A car is a mechanism, but it is not a computer (and for a long time there were no computers in car architectures). Nature is a mechanism in the sense that every event has a prior cause, and without human intervention that prior cause is determined. It is determined what the result of two chemicals mixed in the right quantities will yield, the prior events of placing two chemicals in proximity will cause the chemical product to be produced (this is a mechanism but not a computation, we'll get to this). So, yes, I am saying the nature of a mechanism are that its actions are predetermined. The chain of events that define the mechanism are determined. If it has the right parts and energy is supplied in the right amount and form, the mechanism will always do the same thing, just as a computer program given the same input will always generate the same output (although some computer programs may get their input from the environment so the output is not determined, we'll get to that). There are natural mechanisms (like a growing fetus), and there are artificial mechanisms, like a car or a computer. If it's artificial, man built it, if not, nature built it. All artificial mechanisms are derived from natural mechanisms (their parts and the energy to drive them comes from nature but is put together by humans). When I think about the type of mechanism nature is and the type of mechanism a computer is, what's strikes me is that nature is largely analog (some digital and very little binary) and computers are digital (and mostly binary), which argues that nature of the universe is NOT a computer. Even if you consider architectures other than Van Neuman, computers are still digital (and binary). Neurocomputers are not Van Neuman, but for a neurode to fire, it's inputs must reach a threshold: if it reaches that threshold it fires, if it does not reach the threshold, it does not fire (i.e., it is a binary event whether it fires or not even though the input is statistical). It is possible to build non-binary computers. Since binary means two voltage levels, one low and one high, it is possible to build a computer with three or four discrete voltage levels (or any number of discrete voltage levels), in which case you would have to base your computations on a ternary or quartenary or some other number system than binary. This would still be a discrete artificial mechanism which is digital although non-binary. Now nature is largely analog, energy increases or decreases in a continuous fashion. You don't have discrete events with heat for example, it rises continuously from absolute zero. However, at the quantuum mechanical level you do have some discrete events in nature although they are not binary. You have for example s and p orbitals. Which orbital an electron is in depends upon its energy state. If the energy is sufficiently high it goes to a different orbital (this is discrete, like a threshhold, but not binary as there are not just two orbitals but many orbitals and energy states). There are a few binary events in nature, like the firing or non-firing of an electrical impulse between two neurons. This again is a threshhold binary event, where once a certain chemical concentration threshold is met in the presynaptical vesicle, the neuron fires and transmits the contents of the vesical to the post-synaptic site. But binary events in nature are very rare, the universe is largely non-binary and therefore not like most computers. Now I will qualify what I said about computers being digital somewhat. Actually, since the binary state in a computer is two voltages, and since it takes a small amount of time to rise from a low voltage to a high voltage, or to drop from a high voltage to a low voltage, the computer actually has some analog features. But although the signal from low to high is not instantaneous this does not make it continuous, therefore it is not really analog. One can distinguish between two states (binary) or multiple states (discrete) and continuous (an infinity of states). Nature is mostly continuous and computers are pretty much binary or at least discrete. Therefore, nature or the universe is not a computer and does not do computations. Take gravitation. As two masses approach each other the gravitation increases according to the inverse square law. But the gravitational energy between the two masses is not performing any sort of calculation, it's just increasing or decreasing continuously. Let's not confuse what the physicist is doing and what nature is doing. Natural energy is varying continuously, and the physicist can calculate the gravitational energy using a mathematical law (the inverse square). But nature is not calculating to gravitate. The same thing with chemistry. When chemicals are sufficiently proximal, they combine in certain ways, they have, this is determined as a part of the mechanism in nature, but this is different than the chemist who artificially mixes them in certain quantities and does calculations to determine those quantities. In biology, how an ovum divides after being fertilized, and the events that lead to a fully developed organism is predetermined. Granted nature is a mechanism that occasionally breaks down and doesn't produce the right result (a deformed child for example), just as an artificial mechanism like a car breaks down. So, in conclusion I am saying that nature and computers are both mechanisms (determined), one natural and one artificial. But nature is largely analog (continuous) and certainly not binary, whereas computers are digital and almost all binary (all non-binary is possible to build), so nature is not a computer and hence nature or the universe does not do computations. Note the foregoing is an argument that nature is not a computer as it is not binary, but it is still possible that it is doing non-digital calculations, i.e., continuous calculations as is done to some extent in calculus with curved lines and areas under curved lines. Is there any sense in which the inverse square gravitational pull can be considered a continuous (mathematical) calculation? It seems there are just forces which can be described by mathematical law where events and objects vary according to the mathematically describable force. Does this make it any sort of calculation? My inclination is to say not. It depends what definition we are giving to “calculation.” One definition is “a mathematical determination of the size or number of something.” Is the inverse square force of gravitation a mathematical determination of the size of the force? It seems here there is a fundamental consideration. Mathematical determinations are done by human cognition to describe external (in this case physical) events. In the physical or natural universe per se there is no cognition. In this sense there is no mathematical determination of the size of forces by the universe per se. This is a different consideration than is the physical universe mathematically describable to which the answer is yes to a large extent. Still perhaps not always so. Can you mathematically describe color which is a feature of the physical universe? Perhaps you can associate a range of electromagnetic radiation (frequencies that can described with a sine wave, i.e., a continuous mathematical notion) which corresponds to the subjective experience of color in the physical universe. Again, this is a mathematical description and not color per se. I’m getting off on tangents here. In summary, the physical universe is not a computer or like a computer as it is primarily analog and continuous versus digital discrete and binary. And the physical universe is not mathematical in a continuous sense as our mathematical description of it is not the same as it being mathematical in and of itself, although this is harder to argue. Copyright - Eric Wasiolek |
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