differential geometry

[nibot]

Blah. Covariant derivative. Parallel transport. What's the story?

"a geodesic is a curve whose parametrization, when viewed from within the surface, appears to have zero acceleration" (i.e., all of the acceleration is normal to the surface)

The phrase "objects not experiencing external forces follow geodesics" is more of a tautology than I thought.

If gravity is actually a warping of space-time — so that there's not actually any 'force' of gravity, but rather falling objects travel in "straight lines" along geodesics in space time — why is there still the occasional mention of graviton messenger particles for the gravitational force?

sleepy time.

Comments

[travisgarrett.livejournal.com]

This has been great Tobin - you should come to UNC! I like it a lot at least. Yeah, my official project is working on computer simulations of black hole mergers - should be the first test of strong gravity when LISA and Ligo work - I've got a summer grant to work on LISA motivations, so I'm really happy. And there's lots of cool stuff here - in addition to my theory stuff we're getting strong in cosmology with new hires, the carbon nanotube stuff is really cool (I really hope this space elevator thing pans out), we share a mid-energy particle accelerator at TUNL, the biophysics, especially the neuron stuff is fascinating - I almost thought about switching to that - and if you're considering astronomy we're about to get our own telescope in Chile (17% viewing time, not too shabby) which is really cool. Anyways, good to talk to you, see ya later...

[nibot.livejournal.com]

LISA sounds awesome.. it's almost too bad it's a JPL project, 'cause it would be so much fun to work on.

I should check out this neuron stuff. Hadn't heard about that. Man, it's getting down to the wire.