The bowling ball illustration of gravity

When we were all small children, our teachers tried to deceive us into thinking that gravity was just like when you put a bowling ball on a mattress. If you doubt that this pedagogical disaster is mainstream, then take a look here, here, here, and here. The explanation goes something like this:

“Teacher, why do heavy objects emit more suction power than lighter ones?”
“Well, you know how when you put a bowling ball on a mattress, things will roll towards it?”
“Yes?”
“Well it’s just like that! The bowling ball is a heavy object, the things rolling toward it are lighter objects, and the mattress is the fabric of space!”

Can you believe that? That’s called bullshit. The only reason why the things roll toward the bowling ball in the first place is because of gravity, which is the very thing we are trying to understand! All science teachers who have ever used that illustration should be subject to intellectual denazification.

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7 thoughts on “The bowling ball illustration of gravity

  1. BTW, this argument is totally lame. No one is arguing that gravity IS bowling balls on a trampoline, they are arguing that it acts LIKE bowling balls on a trampoline.

    So when Jesus said “be fishers of men” he didn’t mean to go out and get a rod and reel and hook you a man.

    It’s a metaphor !!!

    The trampoline analogy isn’t trying to explain WHY bowling balls emit ‘suction power’ but rather it is an attempt to explain the features of the power they emit, and the mechanisms by which other objects know that the emission has occurred and behave accordingly.

    The trampoline analogy describes the topology of space time well, and it tells you what the immediate cause of apparent force of gravity is.

    The immediate cause of the apparent force of gravity is the curvature of space time.

    In the same way, the immediate cause of the motion of a bowling ball on a trampoline is slope of the fabric of the trampoline (and gravity rolling the ball down hill).

    So, there is no ‘spooky action at a distance’ between to bodies, but instead, each body merely behaves according to the local conditions where each body exists.

    If an object is moving fast enough the point of gravitational attraction will not be the object itself, but rather a place where the object was when it caused space time to curve at some time in that past. Then you can get all sorts of things like gravitational waves, in the same way you could get waves on a trampoline.

    So, again, it is an analogy to help you visualizes arcane mathematics, not a physical model with explanatory power.

    Now, if you want to know WHY massive bodies curve space time, that is an excellent question to which I do not know the answer.

  2. I’ve always wondered what it is about mattresses that attracts bowling balls. Likewise lint to pockets and remote controls to sofa cushions. Clearly there are other unseen forces at work!

  3. Yes, im mysteriously drawn towards the pub on the way home. Ive always wondered how this gravitation force came to be. I took a big beer gutted friend of mine to the pub and he gravitated quicker to the bar than i did. Is this because of his Mass?

    To compare, I took the youngest of my three children to the pub (less mass, 2 years old, no beer gut). I found that not only did my youngest not gravitate to the bar, but the young,sexy ladies in the pub were no longer pulled towards me.

    I see…

    So, to confirm my theory. The pub does have a gravitationall force which is greater depending on the size of beer gut and the ladies are attracted more to the size of wallet.

    Conclusion….

    Put your wallet in the front of your pants to appear to have more mass!

    Joy

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  6. How does one explain the gravitational attraction that women, especially those between the ages of 18 and 30, exert on all males?
    As there is little to no apparent reduction in attractive force over increasing distance — it certainly doesn’t obey any inverse-square functions — this may be an entirely different form of gravity.
    And as women’s attractiveness for males does not appear to diminish even as it is applied to various male bodies, the possibility of the long-sought perpetual-motion machines seems intriguingly plausible.
    Surely some practitioners are investigating this possibility as we speak?

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