**When Gravity Fails**

Einstein's General Theory of Relativity is now over 100 years old and still remains our best description of gravity.

But the elegant Tensor form of Einstein's Field Equations (EFE) masks a critical property - they are basically differential equations of derivatives with respect to spacetime i.e. with respect to the x,y,z and t coordinates.

But, as any mathematician will tell you, derivatives are only valid for "very smooth" functions. Meaning if spacetime becomes "granular" EFE will not apply - for the simple reason that the derivatives are no longer defined.

At some point this granularity of spacetime will become apparent - the center of a rotating black hole could be an example.

So, it's not that you can't solve the EFE in this situation - it's that you can't even write them down!

Content written and posted by Ken Abbott abbottsystems@gmail.com