An attempted explanation of Dark Matter and Dark Energy

My blog is listed as a Planetary Science blog, and that's what all the topics have been about so far. However the thing is that planetary science is an awfully small topic when considering all of astronomy, so with this post I widen the topic of this blog to all of astronomy, from planetary science to orbital mechanics to astrophysics. As a result, for this post I will be attempting to explain what dark matter and dark energy are. They're often explained and implied to be much more mysterious than they are, and my explanation will attempt to simplify what exactly they are and their effect on the universe.

Dark Matter was first hypothesized in the early-to-mid 1900s to explain the missing mass needed for galaxies to hold together at the speed they travel, as their visible mass alone could not account for that. Dark matter is essentially what the name suggests- just matter that does not in any way interact with light or directly with matter. Imagine it as a pane of glass; light travels through it, does not interact with it, and is not stopped by it. However while we can see the refraction caused by light's slight change in direction while traveling through glass, light simply does not interact with dark matter. However it interacts with gravity, which slightly bends light, letting us use gravitational lensing to view its effect on the universe. Imagining space like Einstein's famous flat, stretchable sheet analogy, photons traveling across the sheet would be bent in very slight, nearly unnoticeable ways that can be measured to see how much gravity is in a certain area. Scientists compare the lensing effect and the amount that the visible mass of an object could account for, and the difference is the amount of dark matter in the area.

Like normal matter, Dark Matter was created in the Big Bang ~13.8 billion years ago, and today it still makes up the majority of matter in the universe, but when it was first created it made up over 60% of all matter. Eventually, the clumps of Dark Matter formed in the Big Bang began to form into clusters and filaments, and formed the structures that galaxies and galaxy clusters now occupy, akin to plaster pouring into a mold.

But where did all of that dark matter go? In the 1990s, studies of the universe's speed of expansion showed that the universe is accelerating faster and faster, and at a loss to explain it any other way, physicists hypothesized that space itself has an energy in it that has a sort of negative gravitational effect, causing the universe to get larger, making more space to further enlarge the universe in a gigantic feedback loop.

Unlike the names suggest, dark matter and dark energy aren't actually at all related to one another except the fact that they don't interact with light. However the effects of them are very much at odds with one another, with dark matter pulling the universe in on itself, and dark energy pulling the universe outwards in a cosmic tug-of-war,a game that dark matter is destined to lose.