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View Full Version : Limits in SR and GR


Naty1
Feb3-09, 10:02 AM
Special relativity limits speeds by v equal/less than c; general relativity limits force by F equal/less than c4/4G.

The above quote comes from motionmountain referenced in learning materials here in Physics Forums....I skimmed the relativity section (it appears quite excellent, and I'd like to dowload it, but it's about 270 pages)...anyway I am wondering about the stated limit above in GR...can some briefly explain the limit??

and on page 241
Space and time are not distinguished globally, but only locally. Matter is required to make the distinction.

What does that mean?

Thanks!