Lars Petrus
Lars Petrus (Born in 1961) currently resides in Silicon Valley, California. Petrus made his name as an internationally accomplished speed cuber in 1982 when he became the national champion of Sweden, and went on to finish fourth overall at the first official Rubik's Cube World Championships held in Budapest, Hungary. He later published his unique method, known as the Petrus system, on the internet. It has become an extremely popular method among intermediate and upper-level speed cubers, although its more recent usage has diminished considerably at the professional level due to the increased predominance of brute force algorithm-based methods. At the age of 44, Petrus continues to be a presence in a sport perennially dominated by teenagers.
World Ranking:
- 3x3x3 Speedsolve: 24th (17.59 seconds)
- 3x3x3 One-Handed: 8th (44.98 seconds)
The Petrus System
The Petrus System was designed as an alternative to the popular layer-based solutions of the early 1980s. Petrus reasoned that as you construct layers, further organization of the cube's remaining pieces is restricted by what you have already done. In order for a layer-based solution to continue after the first layer had been constructed, the solved portion of the cube would have to be temporarily disassembled while the desired moves were made, then reassembled afterward. Petrus sought to get around this quagmire by solving the cube outwards from one corner, leaving him with unrestricted movement on several sides of the cube as he progressed.
The Method
The system uses seven basic steps to solve the Rubik's Cube
- Build a 2x2x2 corner
- Expand to a 2x2x3
- Correct edge orientation
- Solve two complete layers
- Position the remaining corners
- Orient the remaining corners
- Position the final edges
