In 1937, Majorana proposed* that neutral spin-1/2 fermions can be described by real wave functions, rendering such entities their own antiparticles. In spite of an intensive search, there is currently no known subatomic particle that is a Majorana fermion or that supports a Majorana fermion zero mode. Recently, the search has turned to condensed matter systems in which collective phenomena can give rise to Majorana zero modes. A zero-energy localized mode of such a particle would be truly remarkable. A single two-state system would be shared by two such zero modes, even if they were widely separated. Quantum information stored in this two-level system cannot be measured at either zero mode alone and would be highly-protected.

In all of the theoretical proposals for Majorana fermion zero modes in condensed matter systems, topology plays a pivotal role. While the observation of Majorana zero modes in solid state systems would certainly be a singular event in itself, there is also great excitement at their possible use in fault-tolerant topological quantum computation. This rapid response workshop will bring together experimental groups that have searched for or claimed to have observed Majorana fermion zero modes as well as theorists who have designed or analyzed the experiments. Key questions to be answered are:

1. What is the confidence level in the experimental claims?
2. Are the theoretical predictions and experimental observations in agreement?
3. What are the limitations in the use of Majorana fermion zero modes for fault tolerant quantum computation?

*E. Majorana, Nuovo Cimento 14 (1937) 171.