Lights Out

Lights out.

Lights Out on Petersen Graphs

We establish some preliminary results for Sutner’s σ game, i.e. “Lights Out,” played on the generalized Petersen graph P (n, k). While all regular Petersen graphs admit game configurations that are not solvable, we prove that every game on the P (2n, n) graph has a unique solution. Moreover, we introduce an exceedingly simple strategy for finding the solution to any game on these graphs. Surpri...

LIGHTS OUT! on Cartesian Products

The game LIGHTS OUT! is played on a 5× 5 square grid of buttons; each button may be on or off. Pressing a button changes the on/off state of the light of the button pressed and of all its vertical and horizontal neighbors. Given an initial configuration of buttons that are on, the object of the game is to turn all the lights out. The game can be generalized to arbitrary graphs. In this paper, C...

The night the lights went out.

MIT, Harvard, and the surrounding areas lost power from 4:26 to 6:37 p.m. yesterday. The outage threw the Institute into darkness — classes were canceled, MBTA service was delayed, and police were dispatched to direct traffic. Emergency power remained on in dormitories and around campus. The problem is thought to be related to a transmission line in the area, said Michael Durand, NStar spokesma...

Lights out: deactivation of the phototransduction cascade.

The phototransduction G-protein-coupled signaling cascade is an extremely rapid response to photons of light. Equally important to activation of signaling is switching the signal off. A variety of strategies, ranging from the action of kinases and phosphatases, to feedback regulation by substrates and small molecules, ensures efficient inactivation. Here, we focus on phototransduction in Drosop...