The last time Hackerfall tried to access this page, it returned a not found error. A cached version of the page is below, or clickhereto continue anyway

Optical solutions to NP-Complete problems

The purpose of this research is to use light and other signals to perform computations. Several devices for solving NP-complete problems have been proposed. This kind of solving problems is also called computation with time-delays.

Here are some properties of light useful for our system:

Basic ideas:

Problems that have been solved by using this idea:


On some problems it can be faster than digital computers.


The required amount of energy is exponential.

Note that this difficulty is not specific to this system only. Other major unconventional computation paradigms, trying to solve NP-complete problems share the same fate. For instance, a quantity of DNA equal to the mass of Earth is required to solve Hamiltonian Path problem with 200 cities using DNA computers

Video: Optical computing for the subset sum problem

Continue reading on