How much metaphysics is quantum physics

Quantum mechanics: Quantum physics is metaphysics with physical means

From quantum theory to reality

Against this background, Mermin's defiant saying “I won't shut up” can be interpreted as a plea for a physics that is not satisfied with metaphysics, but does not completely ignore it: “I want to celebrate the weirdness of quantum theory, not deny it "He justified his statement. Finally, quantum physics tells us something interesting about the way we think. "About how certain powerful but flawed mental tools that once seemed natural to us still infect our thinking in subtly covert ways."

Classical physics in particular was meant by this. Their conceptual tools have proven too limited for the quantum world, yet we need them to describe tables, lamps, and cars. They shape our understanding of reality. And this is exactly what leads to a clash with the quantum understanding - which perhaps says something about our previous understanding of reality.

For example, if you want to measure the length, height and width of a table, you use a tape measure. The table and staff are - as they say - two locally independent objects. In terms of quantum theory, on the other hand, one would have to describe the situation as follows: rod and table interact, so that in the end a new - a non-local - system of scale-table emerges that claims reality for itself. Scale and table as local individual objects are not real.

Of course, we don't describe everyday things that way. But quantum objects like electrons are. And for this we need Schrödinger's state or wave function, the core of the quantum theoretical description. It defines what we can measure on the electron.

Two objects become one

The inconsistency arises the moment we look at it through classic glasses. Classically we say: We measure properties of the electron with an apparatus. The quantum physicists say instead: The measuring apparatus interacts with the electron in such a way that after the process a single overall state of the electron-plus-apparatus results.

So we no longer speak of two separate objects, but of a single one, the parts of which can also be far apart and "entangled" with one another. The Schrödinger equation predicts all of this. In other words, it leads us to abandon the concept of "local" reality, which we are familiar with from everyday life.