Higgs Mechanism for Gravitons
Higgs Mechanism for Gravitons
复制标题
DOI：
10.1142/s0217732310033724
复制
发表时间：
2010-03
影响因子：
1.4
通讯作者：
I. Oda
中科院分区：
文献类型：
--
作者：
I. Oda
就像规范理论中的矢量规范玻色子一样，现在已知引力子是在通过标量场凝聚而微分同胚自发对称破缺的过程中获得质量的。关键是我们应该找到引力希格斯机制，使其在平坦的闵可夫斯基时空中产生巨大的引力，而无需非单一传播模式。这通常是通过在标量中包含高导数项并以适当的方式将宇宙常数调整为负值来实现的。最近，Chamseddine 和 Mukhanov 提出了一种类似但不同的引力希格斯机制，可以将负宇宙学常数放宽到零或正一。在这项工作中，我们研究了为什么非酉幻影模式在一般时空维度上与物理希尔伯特空间解耦。此外，我们将模型概括为具有任意势，并阐明了一般模型在什么条件下表现出引力希格斯机制。通过寻找条件的解决方案，我们得到了两类表现出引力希格斯机制的势。一类包括 Chamseddine 和 Mukhanov 在特定情况下的模型，而另一类是全新的模型。
Just like the vector gauge bosons in the gauge theories, it is now known that gravitons acquire mass in the process of spontaneous symmetry breaking of diffeomorphisms through the condensation of scalar fields. The point is that we should find the gravitational Higgs mechanism such that it results in massive gravity in a flat Minkowski spacetime without non-unitary propagating modes. This is usually achieved by including higher-derivative terms in scalars and tuning the cosmological constant to be a negative value in a proper way. Recently, a similar but different gravitational Higgs mechanism has been advocated by Chamseddine and Mukhanov where one can relax the negative cosmological constant to zero or positive one. In this work, we investigate why the non-unitary ghost mode decouples from physical Hilbert space in a general spacetime dimension. Moreover, we generalize the model to possess an arbitrary potential and clarify under what conditions the general model exhibits the gravitational Higgs mechanism. By searching for solutions to the conditions, we arrive at two classes of potentials exhibiting gravitational Higgs mechanism. One class includes the model by Chamseddine and Mukhanov in a specific case while the other is a completely new model.