Aaron D. O'Connell, fully Aaron Douglas O'Connell

Aaron D.
O'Connell, fully Aaron Douglas O'Connell

American Experimental Quantum Physicist, while working under Andrew N. Cleland and John M. Martinis at the University of California, Santa Barbara, created the world's first quantum machine

Author Quotes

I believe that our universe is merely a local patch of spacetime, i.e. there is more spacetime outside the universe. From hence we gain a reference point.

Now, on to God proper. I believe that in the beginning, there was no time. With no time existing, 'existence' in its primordial form evolved into a state of maximum perfection: omnibenevolent, omnipotent, and, as far as logically possible, omniscient. Whether this evolution was fast or slow is another piece of information which does not exist: there was no time. And after this, God wanted to permit his love to flow onto something/someone else. So he created Man in his image, and Angels to serve him, and Earth and Heaven to contain them both. Earth, and the Universe, were indeterministic, as, of course, no-one is going to derive any pleasure out of watching a film which they have memorised perfectly down to the slightest jitter of a quark, as I said before, and Man is going to react differently in an indeterministic universe. Maybe they will treat God and his love differently. Who knows, free will is even more unpredictable than quantum mechanics. And of course God created time and space, so that finite minds, flaws and all, might be able to comprehend the universe He placed them in. And of course God was more subtle than merely willing these things into existence: to give Man some fun problems to solve, he decided to use his new paintbrush Physics to do things like create singularities which expand into full universes, and also, he used his engine of indeterminancy combined with his omnipotence and his paintbrush Physics to shape the universe and life into what it is today. Of course he proceeded to immerse himself in his spacetime-bounded slice of existence, and hence has a consciousness less alien to us, and can recieve, consider and answer prayers without troublesome or freaky transformations being required on spacetime for him to do so.

Speaking of traditionally defined omniscience, God not knowing the exact momentum and position of a particle at the same time or which slit a particle went through is entirely logical and does not compromise His sovereignity over the universe at all. Those pieces of information simply do not exist. Asking for them is like asking you to pinpoint an atom on a wave breaking on a shore and saying that it is the wave in its entirety. I will repeat the assertion again. IT SIMPLY DOES NOT EXIST. God cannot know something which does not exist.

Quantum mechanics defines probabilities to predict the behavior of particles, "rather than determining the future and past with certainty". Because the human brain is composed of particles, and their behavior is governed by the laws of nature, Stephen Hawking says that free will is "just an illusion".
Assuming that an indeterministic interpretation of quantum mechanics is correct, one may still object that such indeterminism is for all practical purposes confined to microscopic phenomena. This is not always the case: many macroscopic phenomena are based on quantum effects. For instance, some hardware random number generators work by amplifying quantum effects into practically usable signals. A more significant question is whether the indeterminism of quantum mechanics allows for the traditional idea of free will (based on a perception of free will — see Experimental Psychology below for distinction). If a person's action is the result of complete quantum randomness, however, this in itself would mean that such traditional free will does not exist (because the action was not controllable by the physical being who claims to possess the free will).

Under the assumption of physicalism it has been argued that the laws of quantum mechanics provide a complete probabilistic account of the motion of particles, regardless of whether or not free will exists. Physicist Stephen Hawking describes such ideas in his 2010 book The Grand Design. According to Hawking, these findings from quantum mechanics suggest that humans are sorts of complicated biological machines; although our behavior is impossible to predict perfectly in practice, "free will is just an illusion." In other words, he thinks that only compatibilistic (deterministic) free will is possible based on the data.

Early scientific thought often portrayed the universe as deterministic, and some thinkers claimed that the simple process of gathering sufficient information would allow them to predict future events with perfect accuracy. Modern science, on the other hand, is a mixture of deterministic and stochastic theories. Quantum mechanics predicts events only in terms of probabilities, casting doubt on whether the universe is deterministic at all. Current physical theories cannot resolve the question of whether determinism is true of the world, being very far from a potential Theory of Everything, and open to many different interpretations.

The time dependent Schrödinger equation gives the first time derivative of the quantum state. That is, it explicitly and uniquely predicts the development of the wave function with time.

So if the wave function itself is reality (rather than probability of classical coordinates), quantum mechanics can be said to be deterministic. Since we have no practical way of knowing the exact magnitudes, and especially the phases, in a full quantum mechanical description of the causes of an observable event, this turns out to be philosophically similar to the "hidden variable" doctrine[citation needed].

According to some,[citation needed] quantum mechanics is more strongly ordered than Classical Mechanics, because while Classical Mechanics is chaotic (appears random, specifically due to minor details - perhaps at a smaller scale), quantum mechanics is not. For example, the classical problem of three bodies under a force such as gravity is not integrable, while the quantum mechanical three body problem is tractable and integrable, using the Faddeev Equations.[clarification needed] This does not mean that quantum mechanics describes the world as more deterministic, unless one already considers the wave function to be the true reality. Even so, this does not get rid of the probabilities, because we can't do anything without using classical descriptions, but it assigns the probabilities to the classical approximation, rather than to the quantum reality.

Asserting that quantum mechanics is deterministic by treating the wave function itself as reality implies a single wave function for the entire universe, starting at the origin of the universe. Such a "wave function of everything" would carry the probabilities of not just the world we know, but every other possible world that could have evolved. For example, large voids in the distributions of galaxies are believed by many cosmologists to have originated in quantum fluctuations during the big bang. (See cosmic inflation and primordial fluctuations.) If so, the "wave function of everything" would carry the possibility that the region where our Milky Way galaxy is located could have been a void and the Earth never existed at all. (See large-scale structure of the cosmos.)

Chaotic radioactivity is the next explanatory challenge for physicists supporting determinism
All uranium found on earth is thought to have been synthesized during a supernova explosion that occurred roughly 5 billion years ago. Even before the laws of quantum mechanics were developed to their present level, the radioactivity of such elements has posed a challenge to determinism due to its unpredictability. One gram of uranium-238, a commonly occurring radioactive substance, contains some 2.5 x 1021 atoms. Each of these atoms are identical and indistinguishable according to all tests known to modern science. Yet about 12600 times a second, one of the atoms in that gram will decay, giving off an alpha particle. The challenge for determinism is to explain why and when decay occurs, since it does not seem to depend on external stimulus. Indeed, no extant theory of physics makes testable predictions of exactly when any given atom will decay. At best scientists can discover determined probabilities in the form of the element's half life.

Thus, the world of quantum physics casts reasonable doubt on the traditional determinism that is so intuitive in classical, Newtonian physics. At the small scales, our reality does not seem to be absolutely determined. Yet this was precisely the subject of the famous Bohr–Einstein debates between Einstein and Niels Bohr. There is still no consensus. In the meantime, humans continue to benefit from the fact that reality obeys determined probabilities at the quantum scale. Such adequate determinism (see Varieties, above) is the reason that Stephen Hawking calls Libertarian free will "just an illusion". Compatibilistic free will (which is deterministic) may be the only kind of "free will" that can exist. However, Daniel Dennett, in his book Elbow Room, says that this means we have the only kind of free will "worth wanting".

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First Name
Aaron D.
Last Name
O'Connell, fully Aaron Douglas O'Connell
Birth Date

American Experimental Quantum Physicist, while working under Andrew N. Cleland and John M. Martinis at the University of California, Santa Barbara, created the world's first quantum machine