After confirming dark matter, in 1998 astronomers discovered that the expansion of universe, previously thought to be slowing down under the force of gravity, was actually accelerating. Some sort of negative gravity had to be pushing the universe apart against the gravity that pulls it together. The force stopping gravity from collapsing the universe was called dark energy. Cosmologists estimate that dark energy is 68% of the energy of the universe, dark matter is 27% and the standard model particle matter is at best only 5%. Since the standard model’s particles only account for a tiny fraction of the energy of the universe, it isn’t even close to being a theory of everything.
Dark energy is a weak effect, spread evenly through space that doesn’t seem to have changed much over time. In equations, it makes space flat so some call it a property of space itself but if so, it should increase as space expands. If it is caused by particles in space, as the standard model assumes every force is, it should weaken over time as space expands but it doesn’t. Particles of any sort should clump together not remain evenly spread and what particle could cancel gravity to push the universe apart? The standard model doesn’t have any explanation at all for dark energy because no particle can have a negative energy.
In quantum realism, our space is the inner surface of a bubble expanding into a quantum bulk that adds nodes as it expands. It follows that an expanding universe must lose energy, just as expanding a box cools the gas within it. New points of space are adding all the time evenly throughout space. Since they are new, for their first cycle they receive but don’t transmit energy. This negative energy effect spread over all space is then dark energy.
That dark energy comes from new space means that no particle cause will ever explain it.