May 02, 2009

Einstein was deeply troubled by quantum mechanics and its skeptical consequences

The Strange Case of Bell’s Theorem from Larval Subjects by larvalsubjects
The debate between Einstein and Heisenberg resembles, in many respects, the debate between the realists and the anti-realists that has been unfolding here in the blogosphere.

Einstein was deeply troubled by quantum mechanics and what he saw as the skeptical consequences of this theory such that we can never determine whether or not the properties discovered through our measurements of particles belonged to particles themselves. Heisenberg couldn’t see why Einstein & Co. were so bothered by this. Adopting the position of the pragmatist, he thought it enough that the measurements be able to make more or less accurate predictions, and that the question of whether or not the velocity or position measured belonged to the particles themselves was– and I absolutely love this expression! –a “distinction without a difference”.

Along comes John Bell proposing a theorem that would actually allow this debate to be decided. Now, I do not wish to take a position on whether or not we have access to the real properties of particles or whether we are forever limited to our measurements. I think this very much remains an open debate that is unlikely to be decided any time soon. Rather, I would instead like to draw attention to something else that arose as a result of experiments based on Bell’s Theorem.

I have occasionally been taking to task for refusing to answer questions like “what is the nature of time?”, “what is the nature of space?”, “what are objects?”, “what are primary qualities?”, and for claiming that philosophy cannot provide a priori answers to these questions. The results of experiments based on Bell’s Theorem provide a nice cautionary tale as to why philosophers should practice prudence in answering these sorts of questions. One of the surprising results of these experiments, conducted by Alain Aspect, was the discovery that particles originating from the same source would spin in exactly the same way when subsequently measured despite there being no recognizable connection between the two particles nor any possible causal connection between the two particles. For all intents and purposes, the two particles behave as the same object, despite being vast distances apart from one another. This is what is referred to as “quantum entanglement”...

What makes quantum entanglement so surprising is that the mirror actions of the two particles acting in tandem to one another takes place instantaneously, violating this causal constant of interaction. This has led some physicists to argue that the two particles themselves are a part of one and the same object and that there is some deeper underlying unity or oneness to reality of which particles are “aspects”. Here then we have a violation of two of our common sense assumptions about the nature of the world:

  • First, we have what looks like an interaction between two objects that violates the locality hypothesis.
  • Second, we take it for granted– as a sort of “transcendental condition” –that objects are localized in space or that they have a simple location in space, yet here we have an object which is claimed to be one object where its parts can exist on two different sides of the universe.

It could be that subsequent inquiry will reveal that the two particles are indeed two objects, not one object, and that the locality hypothesis will somehow be redeemed or salvaged through some sort of discovery as to how these two spatially distributed particles are able to perfectly mirror one another. The point, however, is that this question can’t be answered a priori and were we to set a priori conditions as to what objects must be to be given we would very well be inhibiting this sort of research. Our concepts are not at the outset of research– though there are always provisional ones that guide our inquiry –but rather are the result of research.

When Einstein Met Leibniz– What is Time, Anyway? from Larval Subjects by larvalsubjects
In my view, Leibniz has to be one of the most audacious and creative metaphysicians that ever walked the earth. [...]

In short, Leibniz is claiming that every substance, every thing that exists, already includes all of the qualities, events, and properties that will ever occur to it. When my hair turns completely gray, as it is beginning to do now, this is not a new property of my being, but was already contained in my being from all eternity. Even more bizarrely, when I get into a frustrating flame war or blog battle, there is not someone else that is impacting my being in a particular way, there is no causal interaction between myself and other persons and objects. Rather, these events that befall me are already contained in my being for all eternity and arise from me in a movement from the virtual to the actual. As Leibniz puts it in the Monadology, the monads (substances, objects, entities, etc.,) have no windows by which anything could come in or go out (§7), and any change that takes place within a monad is the result of an internal principle (§11), not a cause and effect interaction between substances. For Leibniz, then, substances are a bit like compact disks...

Now, the real weirdness of Einstein’s relativity arises when we begin to think of simultaneity... Given that Einstein’s theory of relativity requires a radical egalitarianism where space-time perspectives occur, does it turn out that Leibniz (and for that matter Whitehead) were right and that somehow every event that has ever taken place and will ever taken place is frozen as an entity for all time because it continues to exist at that moment for some space-time perspective or another? Where we think of the past as something that elapses or disappears, such that only the “moving present” can truly be said to exist, is it the case that the time I cut my leg with an axe when I was eleven still exists and is still taking place like some frozen pose for all eternity? I don’t know. But here is one place where philosophy and science meet. The scientists give us experimental confirmation of this space-time weirdness. If this is true– and all the measurements and experiments strongly suggest that it is true –what must time be if it is anything at all?

What’s for Dinner? from Larval Subjects by larvalsubjects
The cuisine of India is a bit like Hegel where philosophy is concerned: incredibly sophisticated, nuanced, and unfolding simultaneously on a variety of different levels. You could spend a lifetime studying it and still never exhaust or master it.

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