August 28th, 2011

beartato phd

(no subject)

Ok, status at 6am is I just woke up from a very anxietyful dream about simrob getting hit by a snowplow near the intersection of Forbes and Murray and trying to call 911 and not getting through.

The apartment is still entirely intact. The only sign of hurricane is the concrete block at the foot of the door leading to the backyard is starting to soak up a little water. But I think I've seen it do that during reasonably heavy rains before. Looking out the front door there's lots of plant debris in the streets, but no obvious flooding that I can discern.


Looking at the radar maps, it looks like the center of the storm is already just south of us, in the middle of Jersey. There's currently not nearly as much rain south of the center compared to north of it. I wonder if that's expected to change as the storm drifts up? Dunno.
beartato phd

here I am / (dundun dundun) / biking in a hurricane

Achievement unlocked: biked to and from work for the first time.

Now my desktop at work is all hooked up after the very-poorly-timed-vis-a-vis-hurricane cube-move. I can more relaxedly ssh in from home if the subways still aren't running tomorrow.

My neighborhood is coming back to life: some of the braver bodegas were already open at 10-11am this morning, and it looks like pretty much all of them are now. One or two small restaurants, too. A trailing band of Irene with some sputtering rain and lots of wind is hitting us now.
beartato phd

(no subject)

I got kinda frustrated trying to manually come up with a suitably interesting update scheme for a 2+1-dimensional quantum CA thingy, especially since in 1+1-d, it seemed hard not to reinvent Feynman's beautiful checkerboard model. It occurred to me today to just try random ones and see what they do.

Here's a neighborhood scheme:
The notion is, I can just pick any ol' unitary 4x4 matrix, and apply it to a group of four states (every black dot represents one complex number in a big state-vector spanning the whole 2-d spacelike array). On even time steps I apply it in parallel to each group outlined in red, and on odd timesteps to blue. This way hopefully things "circulate" enough.

Here's a quick little js implementation. Click to generate a new random matrix. I made sure the random number generator is deterministic, so you'll see the same sequence of random matrices each time you reload --- the seed number should appear at the top left. I think #2 and #5, #6 are quite pretty.