But when I got back in my car, I did not get back on the Interstate. Instead I got on US-197, heading south into the desert heart of Central Oregon.
It's such an immediate change of terrain, so different from western Oregon. I had chosen to detour away from the river while crossing the eastern part of the state because I had only recently been up and down the entire Columbia Gorge the previous summer. I'm ever curious about what a new route will look like, and I like to use what might be another typical Oregon-to-Colorado road trip to see areas of the state that are new to me, or which I haven't seen in a while.
Driving along US 197 into the empty hills, one has Mount Hood smack in one's rear view mirror much of the time, like a sentinel bidding you good-bye. It's startling to look up and see it looming there. Going further south, you can see the high Cascades spread out to the west---Mount Jefferson and The Sisters, as well as the smaller peaks. You can't ever see them this way from the western side. Being on the eastern side seems like being "backstage."
As I piloted the Bimmer of the seemingly endless waves of ancient volcanic hills, and and down in the valley of the Deschutes River, my mind turned back again to physics.
Recently a Facebook friend, someone I've known since high school who is now a medical doctor, put up a wall post specifically soliciting my opinion regarding this NBC news web article on quantum entanglement, one of the "spooky" phenomena of modern physics discovered over the last century.
The contents of the article were nothing new and groundbreaking, but it was fun to answer his post nevertheless. Here was my response:
As you can see, I basically punted on furnishing an intelligent physics comment. Instead I posted a small anecdote from my first year of graduate school in Austin. That's because I really don't know much about the subject matter of the article. In a way, that's a shame. I wish I did know.
As it happens, I was not there to ask him about physics per se, but to seek information about physicists to contact in Moscow, since I was about to leave on a long summer trip that would take me through Russia. At the time it was still a big deal to go there, and it was very hard to find out information from the other side of the world. Basically I was going blind, except for information from Let's Go.
Back then I never would have dared to wander into DeWitt's office on my own initiative (although I did pull some gutsy stuff like that at times on my ow). Instead the visit there was suggested by another professor I knew who assured me that DeWitt would welcome the chance to help me about this. Physicists of the old school saw themselves as international collaborators in the scientific mission, and there was a sense of noblesse oblige about helping people make contact with each other.
Whether it's a weakness or strength, of my characteristic traits is that I tend to follow the advice of people I respect. The advice Prof. DeWitt gave me is among those times.
Certainly I was already inclined towards the direction I followed, but in any case, I decided soon after that meeting to forgo trying to understand quantum mechanics in a deep way while I was still in graduate school.
Instead I decided I would focus completely on non-quantum physics, in other words, what is known as classical physics.
In the eyes of physicists, there are essentially two realms of nature---the classical and the quantum. Physicists often use the phrases"on the quantum level..." and "on the classical level..." while talking about nature.
Basically the classical level is the macroscopic world, from the extremely large---such as clusters of galaxies, including all of astrophysics---down to the level of every life, and then down to the microscopic level of how atoms bump into each other. It includes all of the physics prior to the year 1900, including all of electromagnetism up until that point.
The classical level is the world of Newtonian mechanics---the billiard table universe, in which all of cause and effect plays out in a completely deterministic fashion. In the classical viewpoint, if a phenomenon is apparently random, it is only because of use of approximation, or missing information.
Classical physics even includes much of the revolutionary physics of the Twentieth Century. For example, Einsteinian relativity---the description of very fast motion near the speed of light, and of very intense gravitational fields---is entirely classical. Our current theory of gravity---Einstein's General Theory---is still purely classical.
The quantum level is generally the world of sub-microscopic phenomena. Quantum physics is necessary to describe how electrons behave in the orbits of atoms, for example. It is also necessary to describe some of the behavior of light, wherever light needs to be modeled as photons, such as in lasers.
The hallmark of quantum level is that it is not deterministic but probabilistic. The universe on a quantum level plays out in a statistical fashion. Predictions of future behavior can never be made with certainty. This is not due to approximation or missing information. It just is the way things are, at least if you buy the prevailing interpretation of quantum physics. This famously bothered Einstein, who was fond of stating "God does not play dice." But Einstein lost the debate on that point.
One of the assumptions of physics over the last century is that laws of quantum physics, not classical physics, are the true fundamental rules of nature. In this view, classical physics, including Newtonian theory, is an approximation for the case of macroscopic conditions. Underneath it all, one asserts, the rules are always truly quantum in nature. But how to reconcile these two two realms?
This has led to great frustration in physics for many years. Generally physics has been mired in the mud for decades trying to grope with this reconciliation between the classical and quantum worlds, but of which seem to work perfectly fine within their province of validity. Fusing the two into some master theory has simply not been possible until now. By the way, string theory (cough, bullshit, cough) is one of the established attempts at line of thought in this direction.
If you peruse the research of theoretical physics over the last half century, much of it has been along the lines of trying to unifying classical and quantum mechanic by developing a quantum theory of gravity. That's what Bryce DeWitt was involved in. He passed away in 2004 without seeing the establishment of such a theory. But that's not really his fault. Instead it's a deeper issue with that whole line of thought, an issue I seemed to intuit back then without delving deep into the existing theory.
I never bothered to even begin to approach quantum gravity in graduate school, even though it was where most students in the theoretical side of things tended to go. I shied away partially because I didn't think I knew enough about old fashioned classical physics yet---e.g., the detailed intricate clockwork universe of planetary motion.
Also, frankly, as I mentioned, there was something about the whole approach to quantum gravity that bothered me. There were so many smart and talented people working on---why hadn't they figured it out yet? Maybe there was something more deeply wrong about the whole approach. The fundamental equations of physics, both classical and quantum, had a breathtaking beauty in their mathematical and philosophical simplicity. Yet all the existing approaches to quantum gravity were extremely complicated on both counts. Folks assumed that once that the right theory was found, it would indeed be simple, but it the mean time, it seemed very complex.
For these reasons, I decided that in graduate school I wouldn't even try to compete with all that effort it what was supposed to be the "cutting edge." Instead I would spend my effort becoming a classical physics ninja. I would get really sharp at it, and that's exactly what I did, until the fundamentals became as accessible to me as basic arithmetic. At that level, one can begin to be creative with theory. One can begin to poke it, bend it, and explore possible wrinkles and consequences.
Thus my dissertation and the book I authored with my adviser W.C. Schieve is one hundred percent classical throughout. My adviser originally found it odd that I would go this route, but I found a classsical niche that no one else was exploring, and just ran with it. In the end, he was highly satisfied with the line of thought we pursued, and I felt I had accomplished the mark I set for myself.
The topic I explored back then was, to be sure, an extreme fringe case of classical mechanics---the study of how multiple particles systems interact when the particles are moving past each other at speeds near the speed of light. But it is nevertheless completely classical. It was a tremendous privilege to get to spend a couple years of my life thinking deeply about such things.
But the assumption that I had back in Austin was that some time down the road, I would eventually get around to a study of quantum physics in earnest, such I could be creative on that level as well. One day I would be seasoned enough to make the leap to the quantum realm.
Now, as I mention in that Facebook post, it is almost ten years after that arbitrary age at which Prof. DeWitt suggested that one might attempt the deep understanding of quantum theory in earnest. But not only have I not yet mastered it, I barely even tried, as I have dropped out of the physics community altogether. This was by my choice, to be sure. Physics eats up your life. Simply put, I had other things to do for a while. I don't regret my choice.
But while driving up the gorge, and heading out into the desert, it occurred to me that classical physics actually somewhat bores me at this point. This is a good sign. I recognize this attitude as exactly ennui that my elders had back in graduate school, whenever I signaled my interest in classical physics. To them, the classical realm was passé. Even if all classical phenomena were not yet explained, the philosophical underpinnings were well known. The quantum realm was still the unexplored frontier of the mind.
To me, this means that my plan to absorb a deep knowledge of classical physics has truly worked. Not only was I successful back in the 90's with my research program, but now the knowledge of the classical realm has had a good long time to remain fallow in my mind, and to gel as part of my permanent world-view and understanding of nature. Finally I feel as if I have the proper mindset of the physicists of the year 1900, who saw the quantum world with fresh eyes of curiosity, and with eagerness to understand it.
This makes me now wonder about quantum entanglement, the subject of my layman friend's post. What is it really about? Curiosity stirs in me to understand it on deep level. The next time a friend asks about this, maybe I'll be able to give an intelligent and informative answer, rather than simply telling old stories from my youth.
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