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Physics/General and Special Relativity



Can you please explain briefly in a nutshell what is the difference between General Relativity and Special Relativity and under which scenarios that each of them becomes applicable. Also can you please explain why the atomic clocks show different times in different surfaces of the earth. Is it because of gravitational force differences?. Is Newtononian physics sufficient enough to explain for the differences?. Does relativity have an explanation for these differences?

Special relativity covers light, motion, and time in the special case where there is no acceleration.  That's what makes it special.  General relativity was relativity generalized to include acceleration (like gravitation).  They always apply, but you don't need to bother with special or general relativity until speeds are significant compared to the speed of light (special relativity) or gravitation is way stronger than Earth's.  Newtonian physics doesn't encompass either, they're extensions beyond it, but Newtonian physics is almost always good enough for normal human applications.  Exceptions like GPS exist, but are way in the minority.  Relativity (if you take a class on it) does provide an explanation for these differences...but a full course on relativity is way beyond the scope of this forum.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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