Why is High Energy Physics Lorentz Invariant? [Hint: It's not what you think!]

Have you ever wondered why the universe is Lorentz-invariant? In this letter, I attempt to prove that:

Cosmology+Quantum Mechanics ➞ Lorentz Symmetry

More precisely, if you require to live in a big universe, for a long time, and have a consistent  effective quantum field theory (which includes gravity), then high energy processes (that, for example, happen in Large Hadron Collider), cannot see a preferred reference frame, and thus must be Lorentz-invariant. Read more here.