It's taken me a while to write another blog post about Adam Becker's fascinating book, "What is Real? The Unfinished Quest for the Meaning of Quantum Physics."
My first post was "Reality requires a broad scientific look, not narrow mystic visions." This reflects the central theme of Becker's book: observations require an interpretation to make them truly meaningful.
The "shut up and calculate" view of quantum physics, which is embraced by many, if not most, of those working in this field, is roundly criticized by Becker -- and other like-minded scientists. As you'll read below in a lengthy excerpt from the final pages of What is Real?, science seeks meaningful interpretations, not simply accurate predictions.
A common example is the Ptolemaic versus Copernican view of the solar system. Ptolemy had the Earth at the center, and managed to predict the motions of the planets quite accurately through a complicated system of epicycles (basically, circles within circles).
Copernicus put the Sun at the center, which turned out to be the accurate conception. But predictions alone weren't able to resolve the question of what entity was at the center of the solar system.
Quantum physics is in a roughly similar situation, as noted in my first post.
It isn't at all true that scientists fully subscribe to the New Age'y view that consciousness creates reality at the quantum level. There are several other theories that predict quantum phenomena equally well as the Copenhagen interpretation, which is known for both "shut up and calculate" and "a measurement brings a single reality into being."
As Becker says below, there are various interpretations competing for ascendancy in quantum physics. One of them may turn out to be correct. Or a currently unknown interpretation may turn out to be correct.
What I liked about Becker's book is how clearly he describes both the strengths and weaknesses of science. While it is our best means of understanding reality, hugely better than religion, scientists are prone to the same biases, emotional flaws, and contorted thinking as everyone else is.
Science, though, has self-correcting mechanisms built into it. As Becker notes, reality pushes back against scientific theories. And scientists want reality to do this, as powerfully as possible.
This is why science steadily progresses, while religion, mysticism, and other forms of supernaturalism don't. There's no demonstrable reality to push back on various dogmas, because there is no evidence that a supernatural realm even exists, much less what it might be like.
So there are thousands of different religions in the world, each claiming that it knows more about a divine reality than the others. They all coexist because there is no way to tell which comes closest to the truth.
Someone claims to have a vision of God, or of supposedly divine light or sound. OK, fine. Psychotics have similar experiences. So do users of psychedelic drugs. So do people in conditions of sensory deprivation. There's no way to tell if a vision of God reflects some objective reality, or just a purely subjective reality.
Admittedly, currently quantum physics is in a somewhat similar situation, since various interpretations of what quantum reality consists of (or means) are competing with each other. But likely scientists will find a way to determine which interpretation deserves to win out.
Again, this might well be a fresh interpretation that is totally unknown at the moment. This isn't a weakness of science, though, but rather a strength. Unlike religion, science is willing to discard a cherished theory in favor of one that meshes better with reality.
And that's why I love science, while rejecting religion. Read on for the excerpt from Becker's book.
Prejudices against certain kinds of people as well as certain kinds of ideas, are pervasive throughout science. But the mere existence of these biases doesn't mean that science is identical to all those other spheres of human endeavor or that scientific truth isn't different from ill-informed opinions with no connection to experiment or reality.
Our biases don't fully determine the content of our best scientific theories -- reality pushes back, and we want it to push back as hard as we can allow it.
That pushback constrains the possible hypotheses we entertain as scientists. There's a wide middle ground between "science is Pure and Perfectly Rational" and "science is just some bullshit somebody made up."
There's still plenty of room for humans to interfere in that middle ground, as we've seen throughout the book. But that doesn't mean science isn't to be trusted -- that's as naive as the Sherlock Holmes view of science.
That being said, the story of quantum foundations does seem to call into question how science works.
We've seen how it doesn't work -- it's not about verification or purely empirical statements, as the positivists thought; it's not about falsifiability, as Popper thought; nor is it about being completely independent from the complex historical forces that have buffeted and buoyed the characters we've met over the course of this book.
So how does science work? Echoing the end of Chapter 11, that's a fabulously complex question. The long answer would take another book.
But the short answer is that science involves a combination of experiment, mathematical and logical reasoning, unifying explanations, and biases that scientists bring to the table from their own lives and the cultures they live in.
We work to reduce those biases; we don't always succeed, but the explicit attempt to account for and reduce those biases is an important part of the process, properly conducted. The whole edifice of science is geared toward this goal.
And, given the phenomenal explanatory power and predictive success of science, it would be foolish to the extreme to give scientific truths no more credence than idle speculation, religious articles of faith, or deeply held cultural values. Science, done right, works hard to respect absolutely no authority at all other than experience and empirical data.
It never succeeds entirely, but it comes closer and has a better track record than any other method we apes have found for learning about the world around us, a world we never made.
...So what is real? Pilot waves? Many worlds? Spontaneous collapse? Which interpretation of quantum physics is the right one? I don't know. Every interpretation has its critics (though the proponents of basically every non-Copenhagen interpretation are usually agreed that Copenhagen is the worst of the lot).
Somehow, something is going on in the world that is related to the mathematics of quantum physics. There is a correct interpretation, though it may not be any of the ones that we have yet.
Simply dismissing the quantum world as a convenient mathematical fiction means we aren't taking our best theories of the world seriously enough, and we are hobbling ourselves in the search for a new theory. Stating that the conclusions of the Copenhagen interpretation are "inevitable" or "forced upon us by the mathematics of the theory" is simply wrong.
It is not true that it's meaningless to talk about reality existing independently of our perceptions, that we must think of the world solely as the subject of our observations. Solipsism and idealism are not the messages of quantum physics.
Instead, we physicists should learn the different interpretations available and keep them all in mind while working. Hold on to them loosely, not dogmatically, and keep a fresh perspective on the work we do.
...We have a wildly successful theory, an embarrassment of interpretations, and a major challenge in moving past our theory to the next one. Pluralism about interpretations might be the right answer, pragmatically, while we face that challenge. Or, if not pluralism, at least humility.
Quantum physics is at least approximately correct. There is something real, out in the world, that somehow resembles the quantum. We just don't know what that means yet. And it's the job of physics to find out.