Cold Neutron Star Model in Brans-Dicke Theory of Gravity
Cold Neutron Star Model in Brans-Dicke Theory of Gravity
复制标题
布兰斯-迪克引力理论中的冷中子星模型
DOI：
10.1143/ptp.48.341
复制
发表时间：
1972
影响因子：
--
通讯作者：
T. Matsuda
中科院分区：
文献类型：
--
作者：
T. Matsuda
在广义相对论之后，人们提出了各种各样的引力理论，但其中许多理论都因其不完整性或与观测数据不一致而被证伪。1> Brans和Dicke 2>提出的标量-张量引力理论是少数几个幸存至今的理论之一。重要的是要研究如何布朗-迪克理论的预测将偏离广义相对论。只有当广义相对论效应本身占主导地位时，两种理论之间的区别才会变得重要。我们将用Brans-Dicke理论研究冷球形中子星星，并与广义相对论的结果进行比较。Salmon a3>已经研究了采用各向同性坐标系的问题。然而，他的形式主义是不一致的，因为他假设了一个不必要的“连接条件”的导数的度规在一个星星的表面，和A在方程。(11)在他的论文中是过度确定的。为了避免这个困难，我们在下面使用正则坐标系。另一方面，萨基扬和姆纳察坎扬4>发展了他们的“广义相对论理论”，除了符号之外，它与布朗-迪克理论完全相同。他们制定了与本文类似的计算方法。然而，在他们的方法中，他们假设A是由弱场近似给出的，所以他们在积分中子星星从中心到表面的内部解时不会得到一致的解。文中给出了计算的一致性方法和数值结果。我们假设了以下行元素：
Various theories of gravity have been proposed after general relativity, but many of them have been disproved for their incompleteness or disagreement with observational data.1> The scalar-tensor theory of gravity proposed by Brans and Dicke2> is one of few theories which have survived till now. It is important to investigate how the predictions of the Brans-Dicke theory would depart from that of the general relativity. The departure between two theories will become important only when the general relativistic effect itself becomes predominant. We shall investigate a cold spherical neutron star in the Brans-Dicke theory and compare the results with that of the general relativity. Salmon a 3> has already investigated the problem adopting an isotropic coordinate system. His formalism, however, is inconsistent because he assumes a needless' junction condition of a derivative of the metric at the surface of a star, and A in Eq. (11) in his paper is over-determined. In order to avoid this difficulty we employ the canonical coordinate system in the followings. On the other hand, Saakyan and Mnatsakanyan4> have developed their "generalized relativistic theory," which is identical to the Brans-Dicke theory apart from the notation. They have formulated the method of calculation which is similar to the one in the present paper. In their method, however, they have assumed A to be given by a weak :field approximation, so they would not obtain a consistent _solution in integrating an internal solution from the center to the surface of a neutron star. In this letter, the consistent way of the calculation and the numerical results are presented. We have assumed the following line element: