Gravity does not have polarity, it only attracts.
An analogy with magnetic or electric fields is appealing (because they are all field forces, decay with the square of the distance, etc...) but science is not made of analogies, it is made of observations. And no one has observed gravity repulsion.
Gravity is in fact much much weaker than the electric force (the factor has 42 zeros), and the only reason we feel gravity is because there is no repulsion, so all those little tiny mass pulls add up to something sensible. Electrical forces, albeit much stronger, usually cancel each other out due to an equilibrium of positive and negative charges.
This is of course, as far as we have seen in nature.
There is however, a very interesting speculation about what should happen with anti-matter. Would it repel "normal" matter?
In the physics page there is a more in deep answer using the results of quantum.
Recommended reading: Feynman Lectures: Theory of Gravitation
No comments:
Post a Comment