>>38311378This.
Dark Matter is the balancing act of the universe, which is literally what Giratina does. it balances the energy/mass that Palkia and Dialga create to prevent reality from ripping itself apart.
Giratina's lore DOES call to both Dark Matter and Antimatter, though, if we assume that the violence it was banished for was the war between matter and antimatter that began at the start of the universe, and because Arceus was drunk, accidentally made Matter more numerous than Antimatter.
Its Altered/Origin formes also kinda hearkens to both antimatter and dark matter, but also wave-particle duality. Antimatter can't exist alongside matter, so it has to change itself into a more matter-based body for the antimatter interpretation. Darkmatter is, allegedly, not like we really know, super, super dense and immune to certain forces. By entering our world and subjecting itself to forces it is otherwise exempt from, its body has to change to it doesn't collapse spacetime for being too heavy, or bluescreen because it was never supposed to feel things like magnetism. Wave/particle duality interpretation, Giratina behaves as both a centipede elephant and a flying spike worm, until you look at it. You can only know giratina's body when you look at it, and when it is in our world, some factor means it "corrects" to Altered.
Then the Grisious Orb is an artifact that manipulates the fundamental forces of the universe
>>38311320>>38311380Dark Matter's entire "purpose" is that, according to physics as we know it, the universe shouldn't hold together the way it does. The universe behaves as though it is much, much heavier than it is, and thus has much stronger gravity (and other forces, but, gravity is the easiest to explain) to hold itself together thin it ought to by all rights.
"Dark Matter" is basically, the teacher threw up the right answer on the board, we looked down and realized we were a bit off, so added some more to our answer.