David Bindel

@dbindel.bsky.social

1076 Followers 653 Following

Professing computing and applied math at Cornell. Numerical methods for data science, plasma physics, other stuff depending on the day. Director, Cornell Center for Applied Mathematics; Director, Simons Collaboration on Hidden Symmetries and Fusion Energy.

A bush covered with snow in the foreground. In the background, a cherry tree in bloom, with snow dusting the top. Ithaca campus April 20, 2026.
Sunset behind the bell tower on the Cornell campus.
Picture of an office full of boxes.
Green and red sock with a picture of a man on a recliner. Surrounding area the words "ain't no bad joke like a Dad joke."
Calendar page for March, with a picture of a sad cat among a bunch of yarn. The caption reads "Due to your refusal to embrace violence, I will no longer be discussing the revolution with you."
Cornell Libe slope, covered with snow. Cirrus clouds colored by sunset in the background.
Blue and orange sunset. The sky is striped with a few cirrus clouds.
Waterfall surrounded by snow, sheets of ice in front.
Picture of a signal-adapted filter for weighted Birkhoff averaging. The filter magnitude has zeros closer to multiples of the rotation number.
Picture of the amplitude of two filters. One is the "all ones" filter for Birkhoff averaging, one is the filter for weighted Birkhoff averaging. This is the case where both have 12 zeros. Both are 1 at the origin, and decay for frequencies away from zero.
Diagram of a Poincare section of the NCSX stellarator. Labels point to magnetic surfaces, chaotic regions, and magnetic islands. An expanded inset shows the islands more clearly.
Picture of a sample objective function f(x) and a smoothed risk-neutral version E_U[f(x+U)]. The original objective has two minima, one around -0.5 that is very broad and one near 0.8 that is narrower and deeper. The risk-neutral version has similar minima locations, but the value near 0.8 is much higher than for f(x), because of the risk of evaluating at slightly the wrong input value.
Schematic of a stellarator. Differently-shaped electromagnetic coils produce the confining magnetic field, with spiraling field lines that follow magnetic surfaces.
Schematic of a tokamak. Poloidal field coils generate a magnetic field in the toroidal direction. Toroidal field coils (and current in the plasma) generate a poloidal field. Together, the two produce a helical magnetic field.
Schematic of a honey dipper. As it is spun on its axis, the honey clinging to the end is sometimes pulled away from the center (when the honey is on the bottom) and sometimes toward the center (when the honey is on the top).
Picture of a curved magnetic field line and associated charged particle trajectory. In addition to gyrating, the charged particle drifts off the field line.
Picture of straight magnetic fields. Charged particles are shown spiraling around the field lines.
Deuterium nucleus (hydrogen with one neutron) and tritium nucleus (hydrogen with two neutrons) fuse to form a helium nucleus with two neutrons (an alpha particle) with 3.5 mega-electron-volts (MeV) extra energy and a free neutron with 14.1 MeV energy.
Picture of a bunny with a pancake on its head. Text around the image reads "I have no idea what you're talking about... so here's a bunny with a pancake on its head."
Picture of a spectrum next to a picture of a sunspot. The spectrum shows splitting of the spectral lines associated with the Zeeman effect.
Picture of a large Foucault's pendulum.
Picture of a hemispherical resonator next to a dime for scale (the hemisphere is just a little bit bigger).
Picture of a metal prayer bowl setting atop a record player.
Image of G.H. Bryan, a mustachioed man with sharply combed hair.
View across Libe Slope at Cornell. One tree has lost its leaves, the rest are evergreen. The grass remains green.
Clouds pouring over the top of Table Mountain in Cape Town.
Dog looking back from next to a tree.
Mama koala sitting on a branch. Baby koala is sprawled backward out of mama's pouch.