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Dark Energy - Earth will tear apart or not?
Your thirst for dark matter might end here
As we all know that dark energy is believed to be the main reason for accelerating expansion of our universe, so there a question arises out of this that whether this dark energy will cause our earth to tear apart like other planets. To quench your thirst on this matter, continue reading...........
Dark energy is basically believed to be an omnipresent SCALAR FIELD (these are mathematical concepts, no one can give you a so-called 'physical idea about it unless you master the required mathematics. I know that's quite unfortunate, but that's how it is; however, if the field does not change over space-time, it is identical with the action of a cosmological constant). This scalar field has been introduced in the model of the universe to attain the critical matter/radiation ratio, as predicted by Friedmann's model of the universe.
Now, with the expansion of the universe, the mass-density of dark matter (eg black holes; they are not dark energy, they do have rest mass while dark energy does not) decreases while the energy density of dark energy decreases either much less quickly (if the scalar field can vary over space-time) or remains constant (in case of a constant field, in which case we can simply call it the cosmological constant).
So clearly it will outweigh the gravitational effects of matter and force the universe to expand with an accelerating rate. With further expansion, the gravitational effect will gradually become more and more feeble and so the galaxies, stars, clusters of galaxies, the planets, all will fall apart; however, don't worry about the atoms, they probably will not fall apart, as all the three forces other than gravitation has no connection with mass-density of the universe, so the relatively large decrease of mass-density, compared to the energy-density of the universe should not affect them.
So in short atoms will not fall apart, but that's not due to the nuclear force being the strongest, rather it is because the magnitude of that force will remain unaffected by the cosmological expansion.
Only those objects (basically all celestial objects) where gravitation is the most prominent force that holds it together will fall apart. The binding force of an atom is not gravitation, so they will remain atoms, but probably we would then have no planet to build a lab to detect them.