#:It is well known that, just as classical mechanics emerges from quantum mechanics at non-microscopic scales, and classical mechanics emerges from relativity at low speeds, both relativity and quantum mechanics should emerge from the Grand Unified Theory (whatever that turns out to be) at the appropriate scales. | #:It is well known that, just as classical mechanics emerges from quantum mechanics at non-microscopic scales, and classical mechanics emerges from relativity at low speeds, both relativity and quantum mechanics should emerge from the Grand Unified Theory (whatever that turns out to be) at the appropriate scales. |