Monday, March 11, 2024

Physics v. Magic

From xkcd comics.

His point here is that Physics is inherently causal. Things happen because there is some causal sequence of interactions from event A to event B, when A causes B.

For example, the Sun's gravitational pull on the Earth was once thought to be action-at-a-distance, but is not thought of as the Sun perturbing spacetime and a wave traveling to Earth. Or gravitons traveling to Earth.

However Physics often reasons from results, without following a causal chain. Examples are thermodynamics, conservation laws, and Lagrangians.

There are also examples in quantum mechanics. A particle might tunnel through a wall, without any understanding of how it gets through the wall.

In spite os these example, I still believe the universe is inherently local, in cause and effect. Sometimes our reasoning can skip some steps, but only as a mathematical convenience. There is no action-at-a-distance, and no magic.

2 comments:

  1. Pretending that gravitational math models models that can only contain one mass (space time) or toy physics which pretend the universe is two dimensional (Ads/CFT) are scientific is pretty much hocus pocus too.

    That said, the ancient Romans figured out sanitation, plumbing, and basic hygiene to prevent disease by believing in humors, gods, spirits and other supernatural explanations.

    I would also add the world has just recovered from a (manufactured) disease (of unknown origin, ha!) which our 'experts' (quacks) were advocating masking (plague masks), social distancing (magical viral force fields) , and useless injections being called vaccinations (placebo palliatives). How well did that turn out?


    "If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family anatidae on our hands."
    Douglas Adams

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  2. Nice try, Roger...

    More seriously:

    ... But you do give me too many ideas, you know, Roger... Your entire write up is as if you wanted to compress in one shot as many of those different pinches as might humanly be possible by you.

    Hmmm...

    Registered.

    Best,
    --Ajit

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