Like Fluoride or Oxygen.

  • Otter@lemmy.ca
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    1 year ago

    Wouldn’t a high enough force cause the gradient of gravity to differ?

    Unless I misunderstood how that works. I’m picturing a downed powerline that causes large differences in voltage across the ground, which is why you are supposed to shuffle instead of taking a normal step. Would a high enough gravity cause a harmful gradient across the length of a human body?

    • Bizarroland@kbin.social
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      1 year ago

      The term spaghettification comes into mind.

      Like if you were free falling into a black hole, the gravity forces would rip you to shreds long before you ever actually impacted anything because the difference in the force of gravity on the parts of your body that are closer to the black hole and the parts of your body that are farther away are enough to shred you like lettuce.

      • raspberriesareyummy@lemmy.world
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        1 year ago

        I have read popular scientific articles however according to which in a large enough black hole, it may be possible to fall through the event horizon before being inconvenienced by the gravity gradient, and even the smartest physicists do not know for sure what will happen beyond the event horizon. In theory, there could be the beginning of another universe there :) Like - the singularity at the center of the black hole could expand as a big bang into a brand new universe “on the other side”.

    • raspberriesareyummy@lemmy.world
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      1 year ago

      Gradient: the change of a value (here: gravitational force, or rather: potential) over a reference variable (here e.g. the length of the body)

      No, the absolute value of the gravitational force does not matter for the gradient. Gravitational force (potential) is proportional to the inverse distance squared from the center of mass that exerts the gravitational potential. If your distance from the object R is large enough, then the gradient of gravity across the length of your body is negligible: In the worst case, with your body length being s, the gravity at the part of your body closest to the center of mass pulling you would be: F_max = F_min * ( R^2 / (R-s)^2 ), and with s << R, this becomes F_min, the force at the part of your body furthest away from the mass pulling you in.

      This becomes problematic when you get “too close” to the body in question - and where too close begins, depends indeed on the absolute force. But for each black hole, there’s a safe distance at which you could fall around it, assuming no other factors killing you (like intersteller particles, or an accretion disc)