If you have two apples floating in space, it takes positive energy to pull them apart against the force of gravity. Since energy must balance out, this means t

If you have two apples floating in space, it takes positive energy to pull them apart against the force of gravity. Since energy must balance out, this means the gravitational field has negative energy. https://www.livescience.com/33129-total-energy-universe-zero.html https://www.livescience.com/33129-total-energy-universe-zero... For energy balance it does not make a difference if you think of gravity as a real force or an illusion caused by curved space.