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Joined 3 years ago
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Cake day: June 11th, 2023

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  • One of the best things I’ve read recently (wish I could find it again) said that quantum mechanics isn’t about reality, it’s a model of what we can measure and study. We simply can’t know what reality is like at atomic and subatomic scales, we can only model what the measurements say. It turns out we can do a lot of really impressive science with those models (nuclear power, semiconductors, lots of other stuff), but acting as if we know what’s actually going on at those levels is fooling ourselves. Even the people who laid the foundation for modern quantum theory knew this:

    Bohr once commented that a person who wasn’t outraged on first hearing about quantum theory didn’t understand what had been said.

    Heisenberg, when asked how one could envision an atom, replied: “Don’t try”

    • A Short History of Nearly Everything

    So what does this have to do with your question? Well, I’m not saying that fundamental reality does not exist at subatomic scales. But I am saying that we can’t really know anything about that reality until we measure it.

    Did the electron have its spin at creation, or at measurement? We can’t really say, and it’s not especially important.

    A bit of a tangent: we don’t fully understand quantum entanglement over distances (e.g., the fact that we can know the spin of one particle from another entangled particle’s spin even over great distances), but the explanation I like is that both particles’ states are just the propagation of their combined wave equation since they were first entangled. So were their spins assigned at entanglement or at measurement? Well, we don’t know and it’s not a meaningful question because we can’t determine the answer without measurement.

    Your chromosome analogy doesn’t really work because your chromosomes are a classical system. They have been entangled with countless other molecules for as long as they have existed, so we can use our human intuition to reason about their past and future in ways that we can’t reason about things at quantum scales.











  • I agree, I’m sure those kind of manipulations happen all the time. Some are intentionally inflating the price and sometimes investors/fund managers have just drank the Kool-aid and are investing in ways that don’t make sense given the fundamentals. So yeah, stock prices can become completely unmoored from fundamentals because these days the money is in buying and selling, not dividends. In fact, I’d guess that stock prices are unmoored from fundamentals more often than not — when they’re high they’re too high and when they’re low they’re too low due to investor sentiment. But I remain somewhat confident that over the very long term (meaning decades) stock prices have some correlation to fundamentals, so they can’t remain artificially inflated forever. Sooner or later someone will make a killing popping the bubble.


  • Stock prices are set by what people think stocks are worth. Buying a stock is a bet that it will become more valuable in the future (and/or pay dividends). Even with the rise of algorithmic trading, those algorithms are betting the stocks are will rise in value. In theory the cost should be related to the fundamentals of the stock like the company’s revenue, but in practice they are also set by investor’s opinions about the stock’s future price.

    So what causes stocks to go down is people thinking that stocks will go down, and selling before they lose any more money.

    In the case of the AI stock bubble, it’s hard to know what will cause investors to say “this stock is likely to drop on value, or at least not grow as quickly as other investments I could make.” The fact that most AI companies are burning cash and not getting much revenue out of it hasn’t dampened the excitement yet, so I guess investors still believe there’s a way forward that will result in more revenue. Or at least they believe the hype cycle isn’t coming to an end so they’re holding on while the prices go up and hope to sell before their holdings lose too much value. It won’t pop until something deflates the expectations of enough investors to start a sell-off. What’s that going to be? Who knows. It might just be a herd mentality thing where a few people begin to sell and more people follow suit.