2 upvotes, 1 direct replies (showing 1)
View submission: Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science
When watching videos by professors of classical and quantum physics, I've gotten the impression that newer models are effective in greater energies than the previous models they upgrade. For example, general relativity covers greater energy (Mercury's precession in gravity from the sun's much greater energy) than in Newton's gravity, and quantum field theory which accommodates relativistic speeds covers more energy than the original quantum mechanics.
Is that the trend? Also, do the new theories reuse much of the older model's equations and make some tweaks? (whether small or major)
Comment by [deleted] at 06/12/2023 at 22:30 UTC
6 upvotes, 0 direct replies
Its more accurate to say that newer models in physics cover a greater range of energies, both high and low. For instance, QM is necessary to explain a ton of things that happen as you approach absolute zero, like Bose-Einstein condensates.
As for your second question, a key part of any new theory is that it can reduce to an old theory in cases where the old theory's predictions are accurate. For instance, general relativity reduces to special relativity when dealing with flat, Minkowski spacetime, and special relativity reduces to classical mechanics for speeds much less than the speed of light.