Dark matter is the name given to a supposed matter which is not seen directly (ie. by the emission of it's own light), but is inferred to exist based on its gravitational influence on other objects. This does *NOT* imply that dark matter is some fantastic new type of matter. At one time, people suggested that wandering planets or very cool stars might be source of the dark matter. However, that is pretty much ruled out now. Dark matter will gravitationally affect other objects in the exact same way that "regular" matter will (ie. Newton's laws or GR, which ever regime you're in).
Dark energy is the name given to the supposed energy which is seen *ONLY* by its gravitational effects on other objects. Clearly dark matter and dark energy have similarities (due to how they're "seen"), but there are *MAJOR* differences: (1) Dark energy is repulsive. So unlike dark matter, dark energy will force objects to be pushed apart, not brought together. (2) the strength of the repulsion is constant, whereas dark matter's attractive force depends on the distance between the objects. If you're really close to an object, you will feel a stronger gravitational force than if you where really far away. Dark *MATTER* behaves the same way. However dark *ENERGY* doesn't depend in that same way. This leads people to think that dark matter is a type of object (which we don't entirely understand yet) and that dark energy is a property of space itself.
zero-point energy is a possible (and as right now, the best) explanation for what that property of space is. Empty space is not entirely empty. Particles can be created and destroyed. The average energy of that "soup" of particles (and their anti-particle mates) is called zero-point energy. The best estimates for what the zeropoint energy have it being a factor of roughly 10^20 times too small to explain the strength of gravitational repulsion that is measured for dark energy.
Dark energy is the name given to the supposed energy which is seen *ONLY* by its gravitational effects on other objects. Clearly dark matter and dark energy have similarities (due to how they're "seen"), but there are *MAJOR* differences: (1) Dark energy is repulsive. So unlike dark matter, dark energy will force objects to be pushed apart, not brought together. (2) the strength of the repulsion is constant, whereas dark matter's attractive force depends on the distance between the objects. If you're really close to an object, you will feel a stronger gravitational force than if you where really far away. Dark *MATTER* behaves the same way. However dark *ENERGY* doesn't depend in that same way. This leads people to think that dark matter is a type of object (which we don't entirely understand yet) and that dark energy is a property of space itself.
zero-point energy is a possible (and as right now, the best) explanation for what that property of space is. Empty space is not entirely empty. Particles can be created and destroyed. The average energy of that "soup" of particles (and their anti-particle mates) is called zero-point energy. The best estimates for what the zeropoint energy have it being a factor of roughly 10^20 times too small to explain the strength of gravitational repulsion that is measured for dark energy.
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Dark matter & dark energy both are not visible to the naked eye but exert a strong gravitational effect on objects in the universe.
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THE COMPLETE EXPLANATION IS IN MY BLOG:
http://universemass.blogspot.com
http://universemass.blogspot.com