Gravity May or May Not Be “Bipolar”


Andrew Donaldson

Born and raised in West Virginia, Andrew has since lived and traveled around the world several times over. Though frequently writing about politics out of a sense of duty and love of country, most of the time he would prefer discussions on history, culture, occasionally nerding on aviation, and his amateur foodie tendencies. He can usually be found misspelling/misusing words on Twitter @four4thefire and his writing website

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16 Responses

  1. Avatar veronica d says:

    Honestly tho, does anyone else get a bit freaked out by cosmology?Report

    • Avatar pillsy says:

      It’s real analysis that always gets to me.

      There’s just that unfathomably vast set of numbers that we really can’t say anything about at all.Report

    • I can see that. Bigger your perspective on the universe the smaller and more fragile we are. I enjoy it. BTW when doing academic papers, always spell check cosmology, cause take it from me and experience you do not want to submit a rant on cosmetology…still haven’t lived that one down yet.Report

    • Avatar Michael Cain says:

      Big and weirdness doesn’t bother me. Small, OTOH… Quantum mechanics is what chased me out of physics. Electron-slit experiments in particular. Electrons being waves and going through both slits at once if you don’t watch them especially. (Electrons jumping from place to place without crossing the intervening space doesn’t bother me the same way, so I’m fine with flash memory.) I believe what I said to my physics advisor was “If this is how the universe works, I don’t want to know any more.”Report

      • Avatar Morat20 says:

        Just assume the universe is a simulation, granular to the planck length and time, and quantum mechanics is just when the universe is forced to calculate a specific answer, instead of just using some computationally cheaper algorithms. (You know, you don’t need to simulate every drop of water in a stream to know it’ll flow downhill, unless some jerk with a really good set of sensors is measuring the crap out of the flow…)Report

        • Avatar veronica d says:

          But as far as we can tell nature does compute the entire Hamiltonian in all it’s exponential glory. That’s the model. The model works. Simplifications of the model all fail to match experiment in some important ways.

          In some of his video lectures, Susskind describes it this way (paraphrase): a theory like general relativity is durable. You can change all kinds of variables within the theory, and it remains self consistent. By contrast, quantum mechanics is precise and fragile. It works, but each bit is logically connected to every other bit. Any tweaks, the whole system collapses.Report

          • Avatar pillsy says:

            Yeah. In some ways this makes QM (and especially QFT) the more powerful theory, because it lets you rule out a whhole lot more.

            In other ways it can leave everything feeling like a Rube Goldberg machine or a Jenga tower with half the pieces missing.

            I always remember my first encounter with the Spin Statistics Theorem, which says that if particles with integral spins are bosons, and particles with half-integral spins are fermions, the correlations between quantum fields at different points in space time cancel out in just the right way to preserve causality.

            I still can’t decide if it’s incredibly elegant or a ridiculous hack.Report

            • It’s a hack, just like inertial mass equalling gravitational mass so that gravity accelerates everything at the same rate. Some day we’ll find a more elegant explanation, like General Relativity.Report

    • Avatar LeeEsq says:

      Really religious people? They can always say its’ the will of the divine.Report

  2. Avatar Dark Matter says:

    For years I’ve been saying we need to re-write the law of gravity… it’d be nice to live long enough to see that.

    I have mixed feelings about the potential re-write not leading to a star drive.Report