Time for my physical theory of magic. As a reminder, it's totally fictional, applies to fictional universes like MLP, and I don't think that's how physics works in real life.
For simplicity, let's imagine the universe as a two-dimensional object, it will be easier to think of its shape that way. So what shape can it be? It can be like a Möbius strip, which has only one side, but it can also be like a normal sheet of paper, which has two sides. (But it doesn't have edges, so you can imagine
As previously established, I need something that makes magic special, that allows it to bypass a physical limitation that normally applies. And I think the best choice for that limitation is the second law of thermodynamics. It states that in a closed system (and the entire universe is a closed system) the amount of entropy (which can be understood as disorder) must remain the same or (more likely) increase. It also means that some processes are very easy in one direction of time, and very hard
To make things clear: I don't believe magic exists in our world, I'm just considering it in context of a fictional universe, like MLP. I don't like the "It's magic, you don't have to explain it" approach. If magic is an integral part of a fictional world, then it should be explained like any other part of it. And that's what we will try to do here. We'll start with the sources of magic. What causes it? I think what Starlight says in "All Bottled Up" is a good explanation:
Of course there
