标题： 碰撞式彭罗斯过程的高效率需要重粒子的产生 显示英文标题

标题： High efficiency of collisional Penrose process requires heavy particle production

摘要： 如果两个粒子在极端克尔黑洞的事件视界附近发生碰撞，它们的质心能量可以变得任意大，这被称为Ba$\rm \tilde n$ados-Silk-West（BSW）效应。 我们考虑了从无穷远处开始、沿着赤道平面的测地线运动的两个粒子的高能碰撞，并研究了从这种高能粒子碰撞中提取能量以及在赤道平面产生粒子的过程。 我们解析地证明了，一方面，如果产生的粒子与碰撞粒子的质量相同，则能量提取效率被限制在大约$2.19$。 另一方面，如果由于高能碰撞产生了一个非常重的粒子，该粒子具有负能量且必然落入黑洞，则能量提取效率的上限增加到$(2+\sqrt{3})^2 \simeq 13.9$。 因此，通常高达10的能量提取效率提供了强有力的证据，表明产生了较重的粒子。 显示英文摘要

摘要： The center-of-mass energy of two particles can become arbitrarily large if they collide near the event horizon of an extremal Kerr black hole, which is called the Ba$\rm \tilde n$ados-Silk-West (BSW) effect. We consider such a high-energy collision of two particles which started from infinity and follow geodesics in the equatorial plane and investigate the energy extraction from such a high-energy particle collision and the production of particles in the equatorial plane. We analytically show that, on the one hand, if the produced particles are as massive as the colliding particles, the energy-extraction efficiency is bounded by $2.19$ approximately. On the other hand, if a very massive particle is to be produced as a result of the high-energy collision, which has negative energy and necessarily falls into the black hole, the upper limit of the energy-extraction efficiency is increased to $(2+\sqrt{3})^2 \simeq 13.9$. Thus, higher efficiency of the energy extraction, which is typically as large as 10, provides strong evidence for the production of a heavy particle.