What is Real? The Unfinished Quest for the Meaning of Quantum Physics, by Adam Becker

[C C]

-book review-
https://www.nytimes.com/2018/05/08/books...-real.html

EXCERPT: . . . So quantum physics — quite unlike any other realm of science — has acquired its own metaphysics, a shadow discipline tagging along like the tail of a comet. You can think of it as an “ideological superstructure” (Heisenberg’s phrase). This field is called quantum foundations, which is inadvertently ironic, because the point is that precisely where you would expect foundations you instead find quicksand.

Competing approaches to quantum foundations are called “interpretations,” and nowadays there are many. The first and still possibly foremost of these is the so-called Copenhagen interpretation. “Copenhagen” is shorthand for Niels Bohr, whose famous institute there served as unofficial world headquarters for quantum theory beginning in the 1920s. In a way, the Copenhagen is an anti-interpretation. “It is wrong to think that the task of physics is to find out how nature is,” Bohr said. “Physics concerns what we can say about nature.”

[...] For much of the 20th century, when quantum physicists were making giant leaps in solid-state and high-energy physics, few of them bothered much about foundations. But the philosophical difficulties were always there, troubling those who cared to worry about them

Becker sides with the worriers. [...] He makes a convincing case that it’s wrong to imagine the Copenhagen interpretation as a single official or even coherent statement. It is, he suggests, a “strange assemblage of claims.”

[...] Is any of this real? At the risk of spoiling its suspense, I will tell you that this book does not propose a definite answer to its title question. You weren’t counting on one, were you? The story is far from finished.

When scientists search for meaning in quantum physics, they may be straying into a no-man’s-land between philosophy and religion. But they can’t help themselves. They’re only human.

MORE: https://www.nytimes.com/2018/05/08/books...-real.html

[Ostronomos]

Recall that this is actually how reality operates. It is unknown whether or not the material world is illusion or not. The act of observation changes the outcome of the experiment as per the Copenhagen interpretation. This informs us that the empirical physical world may not be at the foundation of all that exists. And indeed it is not!

[Yazata]

. . . So quantum physics — quite unlike any other realm of science — has acquired its own metaphysics, a shadow discipline tagging along like the tail of a comet.

I'm not sure that I'd call it "metaphysics" so much as "physical interpretations" (plural).

In other scientific disciplines that's less problematic than in quantum physics. Botany is about plants, zoology is about animals, molecular genetics is about information encoded in biological macromolecules, petrology is about rocks, vulcanology is about volcanoes...

But what is quantum physics about?

Competing approaches to quantum foundations are called “interpretations,” and nowadays there are many. The first and still possibly foremost of these is the so-called Copenhagen interpretation. “Copenhagen” is shorthand for Niels Bohr, whose famous institute there served as unofficial world headquarters for quantum theory beginning in the 1920s. In a way, the Copenhagen is an anti-interpretation. “It is wrong to think that the task of physics is to find out how nature is,” Bohr said. “Physics concerns what we can say about nature.”

Copenhagen seems to me to be the "shut up and calculate" interpretation that many theoretical physicists today seem to favor when philosophers push on them. They retreat into the icy arid fastnesses of their mathematics and act like that's what quantum physics is all about: Hamiltonians!, eigenvalues! Hilbert space!

Except that these aren't really physical things, they are mathematical constructions used to... what, exactly? Calculate the results of experiments, which in turn are conceived in classical terms.

But when philosophers aren't pushing on them, physicists do seem to think that quantum physics tells them about how reality is, not just about how their experiments will turn out. There's something out there about reality that makes the experiments come out as they do.

And that's where the 'interpretations' come in. How does reality need to be so as to produce quantum physics' strange and counter-intuitive results?

For much of the 20th century, when quantum physicists were making giant leaps in solid-state and high-energy physics, few of them bothered much about foundations. But the philosophical difficulties were always there, troubling those who cared to worry about them

Becker sides with the worriers.

Good for him, so do I.

[Ostronomos]

. . . So quantum physics — quite unlike any other realm of science — has acquired its own metaphysics, a shadow discipline tagging along like the tail of a comet.

I'm not sure that I'd call it "metaphysics" so much as "physical interpretations" (plural).

In other scientific disciplines that's less problematic than in quantum physics. Botany is about plants, zoology is about animals, molecular genetics is about information encoded in biological macromolecules, petrology is about rocks, vulcanology is about volcanoes...
 
But what is quantum physics about? 

The ambiguity of Quantum Physics as a scientific discipline does not prevent it from having an all encompassing reach. I believe that is what would qualify it as metaphysical.
 

Competing approaches to quantum foundations are called “interpretations,” and nowadays there are many. The first and still possibly foremost of these is the so-called Copenhagen interpretation. “Copenhagen” is shorthand for Niels Bohr, whose famous institute there served as unofficial world headquarters for quantum theory beginning in the 1920s. In a way, the Copenhagen is an anti-interpretation. “It is wrong to think that the task of physics is to find out how nature is,” Bohr said. “Physics concerns what we can say about nature.”

Copenhagen seems to me to be the "shut up and calculate" interpretation that many theoretical physicists today seem to favor when philosophers push on them. They retreat into the icy arid fastnesses of their mathematics and act like that's what quantum physics is all about: Hamiltonians!, eigenvalues! Hilbert space!

While I agree that that lessens the awe and mystery of Quantum Mechanics, I feel that it is less of a retreat than an actual means to exploration and discovery. Hence the icy arid fastness would melt away when creativity is applied.

Except that these aren't really physical things, they are mathematical constructions used to... what, exactly? Calculate the results of experiments, which in turn are conceived in classical terms.

But when philosophers aren't pushing on them, physicists do seem to think that quantum physics tells them about how reality is, not just about how their experiments will turn out. There's something out there about reality that makes the experiments come out as they do.

And that's where the 'interpretations' come in. How does reality need to be so as to produce quantum physics' strange and counter-intuitive results?

Essentially reality needs to be all-encompassing. That way, the results of Quantum Physics experiments will have uncertainty as well as multiple universes within them. The Copenhagen Interpretation and Schrodinger's Cat are just two examples of the far-reaching implications of reality. All knowledge stems from experience. Physicists, when making Quantum measurements, interact with a world that is different from Classical everyday reality. 

For much of the 20th century, when quantum physicists were making giant leaps in solid-state and high-energy physics, few of them bothered much about foundations. But the philosophical difficulties were always there, troubling those who cared to worry about them

Becker sides with the worriers.

Good for him, so do I.

Of course. Inquiry into the nature of reality is being increasingly welcomed by those who choose the red pill.

[Magical Realist]

Real is whatever you can interact with.

[Ostronomos]

Real is whatever you can interact with.

Bingo.