As recent discoveries have shown, the visible matter as we see is only (more or less) the (+/-) 5% of the whole Universe as we see it today. The (+/-) 70% is dark energy. And 25% (more or less) is dark matter. We don’t have to confuse these two expressions.
We know very little about these two but there’s a scientific explanation. In this article I will try to explain both, (at least what I know):
Dark energy is (+/-) 70%, of the whole Universe as we see it today.
The Universe seems to expand, this fact can’t be factible according to the Newton’s law of gravity in which two masses attract themselves. So there’s some energy anti-gravitational that acts for Universe expansion.
The density of dark energy ( aprox. 7 × 10−30 g/cm3) is very low, much less than the density of ordinary matter or dark matter within galaxies.
Dark matter is a about a quarter of the observable universe’s total mass-energy. The majority of dark matter is believed to be non-baryonic in nature. Dark matter has not been directly observed, but its presence is implied in a variety of astrophysical measurements, notably when observing gravitational effects that cannot be explained by visible matter alone. For this reason, most experts consider dark matter to be ubiquitous in the universe and has strongly affected its structure and evolution. The name dark matter refers to the fact that it does not appear to interact with observable electromagnetic radiation , and is thus invisible to the entire electromagnetic spectrum, making it extremely difficult to detect using usual astronomical equipment.