标题： 标量电荷在膨胀宇宙中的质量损失 显示英文标题

标题： Mass loss by a scalar charge in an expanding universe

摘要： 我们研究了标量电荷——一个对非相互作用标量场起源的点粒子——在膨胀宇宙中质量损失的现象。 该电荷被放置在两种宇宙学时空的共动世界线上：一个德西特宇宙，以及一个空间平坦、物质主导的宇宙。 在这两种情况下，我们发现粒子的静止质量不是一个常数，而是会随着粒子发射单极标量辐射而发生变化。 在德西特时空，粒子在有限的固有时内辐射掉其全部质量。 在物质主导的宇宙学中，只有当粒子的电荷足够大时才会发生这种情况；对于较小的电荷，粒子首先会失去部分质量，但最终会全部恢复。 显示英文摘要

摘要： We study the phenomenon of mass loss by a scalar charge -- a point particle that acts a source for a noninteracting scalar field -- in an expanding universe. The charge is placed on comoving world lines of two cosmological spacetimes: a de Sitter universe, and a spatially-flat, matter-dominated universe. In both cases, we find that the particle's rest mass is not a constant, but that it changes in response to the emission of monopole scalar radiation by the particle. In de Sitter spacetime, the particle radiates all of its mass within a finite proper time. In the matter-dominated cosmology, this happens only if the charge of the particle is sufficiently large; for smaller charges the particle first loses some of its mass, but then regains it all eventually.