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Monday, June 8, 2015

No, Columbia, We Are Not Quantum Fluctuations

On March 2, 2015 the Physics Department of Columbia University held a colloquium that had the title “We Are Quantum Fluctuations: The Cosmic Microwave Background and the Quest for the Origin of All Structure in the Universe.”

An interesting idea, that we are merely quantum fluctuations. Is there any truth to it? No, there isn't.

Goofy nonsense courtesy of Columbia University

To explain why there is no truth to this idea (either literally or metaphorically), let me explain the idea of a quantum fluctuation. According to quantum mechanics, things called virtual particles are constantly popping into existence for tiny fractions of a second, according to a largely chance process. Such appearances are related to Heisenberg's uncertainty principle, which says there is a certain amount of fuzziness, foaminess or uncertainty at subatomic scales. A very rough analogy might be that if you zoomed in with a microscope on your TV screen, you might see tiny pixels popping into existence very briefly, and then popping out of existence – rather like the flickering static that you used to see on old-fashioned TV sets when you turned to an empty channel.

When one of these virtual particles pops into existence, it is called a quantum fluctuation. One important thing about these quantum fluctuations is that they never result in the sudden appearance of a visible object lasting even a second. There is a precisely measured fundamental constant of nature called Planck's constant that limits how big a quantum fluctuation can be, and Planck's constant only allows the appearance of tiny, invisible “virtual particles” that last for a tiny fraction of a second.

Now clearly you and me are not quantum fluctuations, in the sense that we did not originate through any process like a quantum fluctuation. We arose through biology processes rather than physics processes. But is it true, at the very least, that the particles in our body arose through quantum fluctuations? No, it isn't.

Let's look at the modern scientific account of the origin of the atoms and subatomic particles that make up your body. Your body is made up of molecules which are made up of atoms which are made up of subatomic particles. According to modern science, the hydrogen in your body dates back from shortly after the origin of the universe in the Big Bang, but the Big Bang theory says carbon and oxygen were not produced in any significant amounts by the Big Bang. According to astronomers, the carbon atoms and oxygen atoms in your body originated in one or more distant stars. The idea is that more than four billion years ago, your carbon and oxygen atoms formed in some distant star or stars, and after that star or stars died (possibly in an explosive supernova), such carbon and oxygen atoms eventually found their way to our solar system.

This is a plausible and fascinating thesis – an idea that is sometimes expressed by saying, “We are all star stuff.” But it does nothing to support any claim that we are quantum fluctuations, or that any particle of our bodies arose because of quantum fluctuations.

Let's take things back further in time to account for the origin of the hydrogen in our bodies. What exactly was it long, long ago that produced the hydrogen that is part of the water (chemical symbol: H20) that is a large part of your body?

Hydrogen is made up of protons and electrons, as are other elements (and all other elements are also made up of neutrons). According to modern science, all of the protons, electrons, and neutrons now in existence arose from high-speed energy collisions occurring after the Big Bang. Back near the beginning, everything was so densely packed that matter was constantly converting to energy, and energy was constantly converting back into matter. Eventually when things got less dense and hot, we were left with the subatomic particles (protons, neutrons, and electrons) that make up all atoms.

Such a process is fascinating to consider, but it does not significantly involve quantum fluctuations. The basic equation behind the process is not Heisenberg's uncertainty principle (involved in quantum fluctuations) but instead Einstein's famous equation E= mc2.

So you are not a quantum fluctuation, and none of the particles in your body appeared because of a quantum fluctuation. The heavier atoms in your body formed because of stellar processes, and the particles that make up such atoms are the products of high-speed energy collisions in the incredibly dense and hot conditions following the Big Bang.

So literally it is completely false to say that any of us are quantum fluctuations. It is true that cosmologists think that quantum fluctuations were important in the origin of cosmic structure, but such a fact does not justify any such claim as “we are quantum fluctuations.” Bricks are important in the origin of the structure of our cities, but that would not at all justify a claim such as this to city residents: “You are all bricks.”

But is it true to say “we are quantum fluctuations” in some metaphorical sense? One can imagine things that might be metaphorically described as quantum fluctuations – but only things that lasted just for an instant. For example, if a husband looked with sexual interest at an attractive blonde passing by him on the street, and his wife complained, the husband might say, “Don't worry, honey – that lust was just a fleeting quantum fluctuation.” But it is not at all appropriate to metaphorically refer to people living for about 75 years as quantum fluctuations.

So it was neither literally nor metaphorically correct for some physicist at Columbia University to make the claim that “we are quantum fluctuations.” How can we account for such a goofy statement?

The only way I can account for it is by using an explanation of what I might call “stochastic mania.” Many physicists seems to suffer from this strange affliction, in which they seem to worship chance like some besotted schoolgirl who declares her undying love for a rock musician. Stochastic mania may be described as what happens when some person enthrones chance, thinking that almost everything is the result of chance, even in cases when it makes no sense to believe that chance is an appropriate explanation. By claiming “we are quantum fluctuations,” someone at Columbia University seems to have taken this mania to a particularly ridiculous extreme.

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