Synopsis: The Benefits of Starting Anew

Starting over can increase the chances of reaching a desired outcome among many possibilities, as demonstrated by a new statistical analysis.

Whether it’s restarting your computer or doing over your golf shot, there are times when going back to square one seems like the best course of action. A new statistical analysis by Sergey Belan of the Massachusetts Institute of Technology, Cambridge, considers how hitting the reset button could help in general situations where more than one outcome is possible. The result could help in designing restart protocols for chemical synthesis applications in which a particular reaction product is preferred over other possibilities.

When considering the benefits of a restart, the prototypical situation is that of a random walker searching for a target within a time limit. One can show that the probability of success, that is, reaching the target before time runs out, can improve if the walker goes back to its starting point after, say, several minutes of searching without finding the target. Such a fixed start-over time helps avoid situations where the walker winds up in some distant region far from the target.

In his study, Belan looked at a more general set of problems in which there are multiple outcomes that end the search or process. For example, a gambler may decide to quit playing when he either doubles his money or loses it all. Belan first imagined a restart protocol where the start-over time is varied randomly after each restart. This stochastic approach offers an advantage when the average time to reach the desired result (without restart) is short compared with the average time to reach other outcomes. He then identified the general criteria for finding an optimal restart rate that maximizes the probability of ending up with the preferred outcome.

This research is published in Physical Review Letters.

–Michael Schirber

Michael Schirber is a Corresponding Editor for Physics based in Lyon, France.


More Features »


More Announcements »

Subject Areas

Statistical Physics

Previous Synopsis

Related Articles

Focus: Finding the Ideal Noise-Reducing Network
Statistical Physics

Focus: Finding the Ideal Noise-Reducing Network

The structure of a network, such as an electricity grid, can be optimized to reduce the effects of fluctuations in the network’s inputs. Read More »

Synopsis: Second Law in an Optical Cavity and a BEC
Atomic and Molecular Physics

Synopsis: Second Law in an Optical Cavity and a BEC

Physicists observe entropy production in two intermediate-scale quantum systems, indicating that the systems have undergone an irreversible process.   Read More »

Viewpoint: Constructing a Theory for Amorphous Solids
Materials Science

Viewpoint: Constructing a Theory for Amorphous Solids

Theorists are coming closer to a comprehensive description of the mechanics of solids with an amorphous structure, such as glass, cement, and compacted sand. Read More »

More Articles