Quantum Theory and Determinism

This was the title of another seminar in the series Which Truths Can We Build Upon? Physics and Theology in Discourse, addressing physical, philosophical, and theological perspectives.

Let us start with the conclusions first. From a physicist's standpoint of view, they are trivial.

Causality, the relationship between cause and effect, is an observed phenomenon and has been described quantitatively in physics since Newton, but what does scientific truth mean in this context?

By status, do the students mean our current understanding of God and the universe? Natural sciences make decisive contributions to the latter. I think that modern philosophers and theologians without a good understanding of physics cannot credibly lecture or preach to people today.

With our current level of knowledge, it is impossible to answer the question: Is the future determined? How the answer might look in the future is pure speculation.

The students distributed handouts with German texts of philosopher Ernst Cassirer from his 1936 book Determinism and Indeterminism in Modern Physics.

Cassirer's ideas were shaped by the interpretation of quantum mechanics at that time. So are his statements: Causality and randomness do not contradict but complement each other, and the question of free will should not be mixed up with the question of physical indeterminism.

However, the currently established laws of nature allow us, although only in principle, to determine the future from past events, except for occasional quantum events that we cannot influence.

So, what is called soft determinism in the above slide is indeterminate.

Sabine Hassenfelder wrote that much of the debate about free will in the philosophical literature concerns not whether it exists in the first place but how it connects to moral responsibility.

This means that the question of free will boils down to one's personal view, whether it includes morality and ethical accountability (toward God).

Indeed, further slides addressed the theology of determinism and free will, which Red Baron is no expert on.

Here is a slide the content of which theologians and laypeople alike will gnaw their teeth out.

Lagniappe

In the students' handout, I read a passage by Ernst Cassirer that did not get my approval. Here is the English translation:

Modern physics had to give up the hope of exhaustively representing the whole of natural phenomena with a fixed system of symbols. It is faced with the necessity of applying different types of symbols of schematic "explanations" to the same event: Physics must describe one and the same being as a "particle" and as a "wave" and must not be deterred from this use by the fact that the visual unification of the two images proves to be impossible.

From this, Cassirer conveys that philosophy must also be viewed from various perspectives.

What a misjudgment about physics. None other than Heisenberg bitterly complained that our language cannot clearly describe processes in the atomic realm. Red Baron once wrote an essay in German: Über das Verstehen in der Physik (About understanding in physics).

Sabine Hossenfelder even goes a step further, arguing that much of the supposed weirdness of quantum mechanics just comes from forcing it into everyday language. She is very much a math person and personally doesn't see the need to translate math into everyday language. Once we have the mathematics, and at least someone understands it, it is often possible to communicate it verbally and visually.

*