不是粒子的粒子

　　This year, physicists may have finally spotted an odderon — a particle that really isn't. Particles such as electrons and protons stick around for extended periods, while odderons, a kind of "quasiparticle," blink in and out of existence. Scientists first predicted the existence of odderons in the 1970s, thinking that the particles might materialize when an odd number of teeny particles called quarks get released during the violent collision of protons and antiprotons. Researchers resurrected the decades-old idea when they sent particles crashing into each other at the world’s largest atom smasher, the Large Hadron Collider. The team spotted some strange differences in the way protons collide with other protons as compared to antiprotons, and the existence of odderons may explain why that discrepancy exists.

　　今年，物理学家们可能终于发现了“奇子”——一种实际上并不存在的粒子。诸如电子和质子之类的粒子会长时间存在，而作为一种“准粒子”的奇子则忽隐忽现。早在上世纪70年代，科学家就首次预测了奇子的存在。他们认为，在质子和反质子的剧烈碰撞期间，当奇数个被称为“夸克”的微小粒子被释放出来时，这种粒子就有可能形成。研究人员在世界上最大的原子粉碎器大型强子对撞机上实现粒子相互碰撞，重现了几十年前的构想。研究团队发现，质子之间的碰撞方式与反质子相比存在一些奇怪的差异，而奇子的存在或许可以解释为什么会存在这种差异。