Constraints on shift-symmetric scalar-tensor theories with a Vainshtein mechanism from bounds on the time variation of G.
Constraints on shift-symmetric scalar-tensor theories with a Vainshtein mechanism from bounds on the time variation of G.
复制标题
具有 Vainshtein 机制的平移对称标量张量理论的约束来自 G 时间变化的界限。
DOI：
10.1103/physrevlett.107.251102
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发表时间：
2011
影响因子：
8.6
通讯作者：
G. Esposito
中科院分区：
文献类型：
--
作者：
E. Babichev;C. Deffayet;G. Esposito
我们证明了牛顿常数G随时间变化的当前边界可以对许多有趣的标量-张量理论施加严格的约束，这些理论具有移位对称性和非极小物质-标量耦合。这尤其包括带有Vainshtein筛选机制的类似伽利略的模型。我们强调，如果这种机制能够有效地隐藏标量场在短距离和静态近似下的影响，则通常不会改变标量场的宇宙学时间演化。当物质-标量耦合为1阶时，局部测量的G时间变化太大。
We show that the current bounds on the time variation of the Newton constant G can put severe constraints on many interesting scalar-tensor theories which possess a shift symmetry and a nonminimal matter-scalar coupling. This includes, in particular, Galileon-like models with a Vainshtein screening mechanism. We underline that this mechanism, if efficient to hide the effects of the scalar field at short distance and in the static approximation, can in general not alter the cosmological time evolution of the scalar field. This results in a locally measured time variation of G which is too large when the matter-scalar coupling is of order one.