标题： 李-威克辐射引起的反弹宇宙模型 显示英文标题

标题： Lee-Wick radiation induced bouncing universe models

摘要： 本文讨论了早期宇宙中一个Lee-Wick伙伴感染的辐射阶段的影响。 由于Lee-Wick伙伴可以贡献负能量密度，因此在宇宙的某个早期阶段，当Lee-Wick伙伴处于热平衡时，宇宙的总能量密度变得非常小，使得有效哈勃半径变得很大。 这种可能性导致了宇宙反弹的概率。 正如文章中所示，简单的Lee-Wick辐射不足以产生反弹。 在Lee-Wick辐射阶段，可能存在两种可能性来产生反弹。 一种需要一个冷暗物质候选者来触发反弹，另一种可能性需要反弹温度被精细调节，例如在反弹温度下所有的标准场的Lee-Wick伙伴都不处于热平衡。 这两种可能性都导致度规扰动的蓝倾斜谱。 此外，反弹宇宙模型可以预测手征费米子和无质量规范玻色子的Lee-Wick伙伴的质量下限。 质量限制本质上取决于反弹温度。 显示英文摘要

摘要： The present article discusses about the effect of a Lee-Wick partner infested radiation phase of the early universe. As Lee-Wick partners can contribute negative energy density so it is always possible that at some early phase of the universe when the Lee-Wick partners were thermalized the total energy density of the universe became very small making the effective Hubble radius very big. This possibility gives rise to the probability of a bouncing universe. As will be shown in the article that a simple Lee-Wick radiation is not enough to produce a bounce. There can be two possibilities which can produce a bounce in the Lee-Wick radiation phase. One requires a cold dark matter candidate to trigger the bounce and the other possibility requires the bouncing temperature to be fine tuned such as all the Lee-Wick partners of the standard fields are not thermalized at the bounce temperature. Both the possibilities give rise to blue-tilted power spectrum of metric perturbations. Moreover the bouncing universe model can predict the lower limit of the masses of the Lee-Wick partners of chiral fermions and massless gauge bosons. The mass limit intrinsically depends upon the bounce temperature.