To do that, CERN built the Antiproton Decelerator, which uses electric and magnetic fields to slow the particles from near light speed to about one-tenth of that, he said.

• 为了要做那些,CERN建造了反质子加速器,他说，使用电场和磁场把接近光速度的粒子减慢到光速的十分之一左右。