Former night watchman solves decades-old math problem

Avraham Trahtman, a 63-year-old mathematician, has achieved a significant breakthrough by solving the "road coloring problem," a complex mathematical puzzle that had perplexed experts for nearly four decades. Trahtman, who had previously worked as a night watchman and maintenance worker in Israel after emigrating from the former Soviet Union, found his way back to academia in 1995 at Bar Ilan University.

The road coloring problem, first proposed in 1970 by Roy Adler, C. Goodwyn, and Benjamin Weiss, deals with the theoretical coloring of paths in a network. The core question was whether it's possible to assign colors to a system of one-way roads such that a specific sequence of colors would always lead a traveler to the same destination, irrespective of their starting location.

While the problem's concept is relatively easy to grasp, proving its solvability proved exceptionally challenging. Trahtman dedicated about a year to developing his solution, which he meticulously wrote out by hand on eight pages. His work definitively confirmed that such a coloring is indeed possible, resolving a question that had remained open since the 1970s. The implications of this solution extend beyond pure mathematics, potentially influencing systems that require a predictable state regardless of initial conditions.