MICROSCOPE

There was a fair amount of excitement in the French press
yesterday, as the the results form Microscope - a spaced-based
experiment (micro-satellite) to measure the speed of acceleration due
to gravity - were made public. Confirmation that everything falls at the
same speed has now been accredited to one more decimal place: 2*10^-14.
This is generally seen as an endorsement of Einstein's General Relativity.

This is an important finding for physics - indeed a disappointment for some -
because those trying to unify Astronomy physics all the way down to
Quantum physics had left a margin for a break from this regularity, within String
theory. Perhaps at a greater level of precision, still, ventured the authors...

If one reflects upon this, and in the absence of a story line on how gravity actually
works, it is a little odd that absolutely everything falls at the same speed...in point
of fact, accelerates downward the same. I could be standing on the moon, and the book
I drop will hurry down the same as one on earth, because the mass of the object is not
involved, only the fact of gravity. What will be different is the force of the impact at
it hits the ground, because things weigh less on the moon. As always, Newton's
f = ma holds!

We should probably be thankful for this. As one journalist covering the story remarked,
it would be a very dangerous world to live in if this was not the case.

Conclusion, for now: gravity is a constant, just like the speed of light. The universe Tinder
dates 😚

https://microscope.cnes.fr/fr/premiers-resultats-de-la-gravite-au-microscope