Nov 16 2009

Chopra Mangles Quantum Mechanics – Again

Deepak Chopra has made a career out of misunderstanding quantum mechanics (QM) – and through his popularity, confusing the public. Like many others, he has found a superficial way in which to interpret quantum mechanics to make is seem as if it is congruent with Eastern metaphysics.

And now he has done it again, in that anti-science rag the Huffington Post. Chopra goes beyond the typical New Age distortion of QM, which is basically the claim that QM is really weird, therefore magic is real. Chopra assumes some very specific, and common, misinterpretations of QM. He writes:

Quantum physics tells us that objects exist in a suspended physical state until observed, when they collapse to just one outcome — we don’t know what happens until we investigate, and our investigation influences that reality. Whether or not certain events may have happened some time ago, may not actually be determined until some time in your future — it may actually be contingent upon actions that have not yet taken place.

Chopra is referring to the wave-particle duality of matter, quantum entanglement, and the uncertainty principle – but he gets them profoundly wrong. First he makes the common mistake of interpreting the collapse of the wave function as being dependent on an observer, which is false. QM states that light, electrons, and all fundamental particles exist not as  discrete point particles, but spread out like a wave. We can only describe the probability that they will be in a specific place at any moment, and that probability is the wave function. Particles, when free from interactions with other matter, actually behave like waves (see the double slit experiments).

But when a particle (whether of photon of light or an electron) interacts with other stuff it is no longer spread out but collapses down to a point particle. This is the wave-particle duality of matter. The collapse to a particle, however, is not dependent on any observer – just interaction with other stuff. No observer is necessary. When a photon from the sun strikes the earth and its energy is absorbed by a leaf on a tree in the middle of the jungle, it collapses to a particle. The same is true when it strikes a dead rocky asteroid out in space. Consciousness, and even life, is not necessary.

Next Chopra mangles quantum entanglement:

Scientists in France shot particles of light “photons” into a measuring apparatus, and showed that what they did — now, in the present — could retroactively change something that had already happened in the past. As the photons passed a fork in the apparatus, they had to decide whether to behave like particles or waves when they hit a beam splitter. Later on — well after the photons passed the fork — the experimenter could randomly switch a second beam splitter on and off electronically. It turns out that what the observer decided at that point, determined what the particle actually did at the fork in the past.

Yes, these experiments are fascinating. But they do not describe the future affecting the past, as Chopra misinterprets. They describe what is known as quantum entanglement. When particles are paired or linked in some way – for example when they are created by the same process – some of their properties are linked, even while still being in a wave of probability. For example, if one particle is spin up, the other will be spin down, even though their spin is not determined until much later, and even if the particles are separated by millions of light years at the time of the collapse of the wave function.

Physicists do not pretend to understand the fundamental nature of quantum entanglement – that is a Nobel prize waiting to be won. But it does not represent the future affecting the past. Nor does it represent faster than light, or instantaneous communication. Experiments have been done showing that it is impossible to transmit information faster than light using quantum entanglement. Information is not going faster than light, or into the past.

Chopra is using a common trick of the pseudoscientist – exploit cutting edge science, which the public is not likely to understand, and pretend as if there is proof where there is uncertainty. Take some interesting experiments, then leap way ahead to conclusions that serve their metaphysical purposes, but which are not settled science.

In short – beware of anyone pretending to understand the ultimate implications of QM and that it supports their far out philosophy.

And here is Chopra’s woo philosophy:

It was only with the advent of quantum physics that scientists began to consider again the old question of the possibility of comprehending the world as a form of mind.

Indeed, the quantum theory implies that consciousness must exist, and that the content of the mind is the ultimate reality

The universe is a mind, and consciousness is the ultimate reality. Not surprisingly, a very Eastern philosophy, packaged nicely  for a Western audience.

Another false underlying assumption of Chopra, which he does not state expressly, is that all of this quantum weirdness (whatever its implications) applies to the macroscopic world. This is true, in a way (depending on how you look at it), but highly misleading. All objects, no matter how large, also are waves and particles. However, the wavelength of matter (the degree to which it is spread out, rather than having a definite position) decreases with mass and velocity. This is defined by the de Broglie equation:

λ = h/mv

Where λ is the wavelength, h is Planck’s constant, m is mass, and v is velocity. What this means is that when you start to get larger than a large molecule, the quantum wavelength shrinks to insignificance. When you get to macroscopic objects, the wavelength is orders of magnitude less than the size of elementary particles. So you have a wavelength, but it is so close to zero it can be treated as zero – which is another way of saying you do not behave like a quantum object, but like an object in classical physics.

Chopra, however, thinks that QM applies to everything equally. He writes:

If we do not look at it, the moon is gone. In this world, only an act of observation can confer shape and form to reality — to a dandelion in a meadow, or a seed pod, or the sun or wind or rain. Anyway, it’s amazing, and even your dog can do it too.

He is doubly wrong – not only is consciousness (an observer) not the thing that collapses wave functions, but QM effects do not apply to dandelions or moons (try shooting dandelions through a double slit experiment).

Another reason QM effects are not seen in the macroscopic world in which Chopra’s brain exists is decoherence. Remember that weird quantum entanglement I mentioned? Well, this can be observed only in carefully contrived experimental situations. It exists in nature, of course, but tends to be fleeting, because of decoherence. Whenever either paired particle interacts with other stuff in the universe, it becomes less entangled with its original partner, until they are decohered – their properties are no longer linked. It is hard to keep particles from decohering – in fact this is a stumbling block to the development of quantum computers that exploit QM effects. The particles keep decohering and losing their properties which can be used to store information.

For any macroscopic object, all the particles in that object are interacting with each other and decohering all the time. Again – the weird quantum world collapses to a classical physical world when you scale up to dandelions and people.

Chopra really needs to have a conversation with a real quantum physicist. You would think that before someone makes a career out of promoting a specific scientific interpretation to the public they would make sure they got the science right. But I suspect Chopra doesn’t care about getting the science right. He seems to be working backwards from his metaphysics, and then happily misinterpreting QM to suit his needs.

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