MIT physics finds no quantum neutrino laser possible

MIT physicists have demonstrated that a proposed neutrino laser is impossible, debunking a concept proposed last year. The research reveals fundamental physical limitations prevent creating a concentrated beam of neutrinos, even with cooling radioactive atoms to one-billionth the temperature of interstellar space. Wolfgang Ketterle, the John D. MacArthur Professor of Physics at MIT, describes the two papers detailing the findings as “punch one and punch two,” adding, “Each paper would have killed the proposal.” The team’s analysis, appearing in Physical Review Letters, centers on issues with recoil, the kinetic energy created by the reaction, and the neutrino’s inherent “fermionic” nature. The proposed feasibility of a neutrino laser hinged on achieving nanokelvin temperatures, conditions representing one-billionth the temperature…