1,253 reputation
314
bio website reedbeta.com
location Milpitas, CA
age 29
visits member for 2 years, 3 months
seen Apr 8 at 0:21

I'm a graphics programmer, an amateur physicist, and a sci-fi nerd. I teach computers how to make pretty pictures. I'm excited by beautiful, immersive, story-driven games and interactive fiction. I enjoy messing around with esoteric ideas. I like explaining things.

I currently work for NVIDIA DevTech. Previously, I worked for Sucker Punch Productions on the Infamous series of games for PS3 and PS4.

reedbeta.com - developer blog, OpenGL demos, and other projects. @reedbeta on Twitter.


Feb
14
awarded  Enlightened
Feb
14
awarded  Nice Answer
Feb
10
comment Is anti-matter matter going backwards in time?
I read somewhere that the "one electron going back and forth in time" idea was Wheeler's, not Feynman's originally. (Wheeler was Fenyman's thesis advisor.) Unfortunately I forgot where I heard this, but it was probably in one of Feyman's lectures/writings.
Jan
20
comment Can an electric field align water molecules?
Microwave ovens work because water molecules (and other polar molecules) try to align with the rapidly oscillating microwave field...so I guess it doesn't take that much field strength.
Jan
20
comment Physics of guitar strings
And to the OP, the phenomenon is called guitar harmonics and Wikipedia has a good explanation.
Jan
20
comment Physics of guitar strings
@fqq "one octave higher in pitch than when I press down firmly at the same place", i.e. the 3rd harmonic of the open string, compared to fretting the string to 2/3 of its open length.
Jan
16
awarded  Yearling
Jan
8
revised Is space stretched with no limits by a black hole?
correction: the tape-measure-dropping distance isn't infinite
Jan
8
comment Is space stretched with no limits by a black hole?
@JohnRennie Ahh, too bad! I should've checked it more closely myself. :)
Jan
8
comment Duality in Electromagnetic Spectrum
@Beauness No, all the spectrum has discrete quanta, but the energy per photon is smaller at lower frequency ($E = h\nu$). So for radio waves the discreteness is harder to detect than for light. Nevertheless, radio waves come in quanta as well.
Jan
7
answered Is space stretched with no limits by a black hole?
Jan
7
comment How much extra distance to an event horizon?
If the tape-measure-dropping distance to the event horizon is infinite, I wonder what a falling observer right next to the tape measure would see? Since they hit the horizon in a finite proper time, it would seem they'd have to see an infinite length of tape fly by in a finite time.
Jan
7
answered Do objects launched from Earth retain the Earth's lateral inertia (67,000mph)
Jan
4
comment Coulomb's Law in the presence of a strong gravitational field
@TomAndersen It may still work in a spherically symmetric case, but the OP was asking about curved spacetime in general, IIUC. In general there is no unique notion of the distance between two points, so no way to even formulate a Coulomb-like law.
Dec
25
revised A sees B's clock running slow and B sees A's clock running slow?
added 345 characters in body
Dec
25
answered A sees B's clock running slow and B sees A's clock running slow?
Dec
17
comment From affine space to a manifold?
@Heaviside If you have a geodesic curve that passes through Paris and New York, you can measure the distance along it (tracking it through multiple patches if necessary). And you can measure the angle of the geodesic relative to some reference frame at New York. So, you could say something like "Paris is 5800 km from New York at a heading of 30 degrees". In that sense you could locate Paris relative to New York. But depending on the spacetime there might or might not be such a geodesic, and it might or might not be unique.
Dec
16
comment From affine space to a manifold?
@Heaviside In real life we can describe planes' positions and flight paths using just one patch, the usual latitude-longitude coordinates, because that covers almost the whole Earth. It only breaks down at the poles, and planes don't usually go too close to the poles. So it's in part a question of theoretical vs practical. :)
Dec
16
comment From affine space to a manifold?
@Heaviside Well, I guess it depends what you mean by track a plane. If we lived in a complicated manifold with many patches we could certainly still describe the plane's path as it flies around. But in general we couldn't describe it by just one curve; we'd have to describe it by several curves, one in each patch, which match in the overlap regions.
Dec
16
comment From affine space to a manifold?
@Heaviside Sure you can, you just have to switch to the Atlantic Ocean patch at some point and then later switch to the Europe patch. (Presuming the patches overlap for a certain distance around their edges.)