In the framework of f(T) gravity, we focus on a weak-field and spherically symmetric solution for the Lagrangian f(T) = T + alpha T-2, where a is a small constant which parametrizes the departure from general relativity (GR). In particular, we study the propagation of light and obtain the correction to the general relativistic bending angle. Moreover, we discuss the impact of this correction on some gravitational lensing observables, and evaluate the possibility of constraining the theory parameter a by means of observations. In particular, on taking into account the astrometric accuracy in the Solar System, we obtain that vertical bar alpha vertical bar <= 1.85 x 10(5) m(2); this bound is looser than those deriving from the analysis of Solar System dynamics, e.g. vertical bar alpha vertical bar <= 5 x 10(-1) m(2) [L. Iorio, N. Radicella and M. L. Ruggiero, J. Cosmol. Astropart. Phys. 1508 (2015) 021, arXiv:1505.06996 [gr-qc].], vertical bar alpha vertical bar <= 1.8 x 10(4) m(2) [L. Iorio and E. N. Saridakis, Mon. Not. R. Astron. Soc. 427 (2012) 1555, arXiv:1203.5781 [gr-qc].] or vertical bar alpha vertical bar <= 1.2 x 10(2) m(2) [Y. Xie and X. M. Deng, Mon. Not. R. Astron. Soc. 433 (2013) 3584, arXiv:1312.4103 [gr-qc].]. However, we suggest that, since the effect only depends on the impact parameter, better constraints could be obtained by studying light bending from planetary objects.
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机译：在f（T）引力的框架中，我们专注于拉格朗日f（T）= T + alpha T-2的弱场球对称解，其中a是一个小的常数，参数化了偏离广义相对论（ GR）。特别是，我们研究了光的传播并获得了相对论弯曲角度的校正。此外，我们讨论了这种校正对某些引力透镜观测值的影响，并通过观察评估了限制理论参数a的可能性。特别是，考虑到太阳系中的天文测量精度，我们得到的垂直线alpha垂直线<= 1.85 x 10（5）m（2）;这个界限比从太阳系动力学分析得出的界限更宽松。垂直条alpha垂直条<= 5 x 10（-1）m（2）[L. Iorio，N.Radiicella和M.L.Ruggiero，J.Cosmol。天体物理1508（2015）021，arXiv：1505.06996 [gr-qc]。]，竖线alpha竖线<= 1.8 x 10（4）m（2）[L. Iorio和E.N. Saridakis，星期一。不。 R.阿斯特隆。 Soc。 427（2012）1555，arXiv：1203.5781 [gr-qc]。]或竖线alpha竖线<= 1.2 x 10（2）m（2）[Y.谢和X.M.邓，星期一。不。 R.阿斯特隆。 Soc。 433（2013）3584，arXiv：1312.4103 [gr-qc]。]。但是，我们建议，由于效果仅取决于碰撞参数，因此可以通过研究来自行星物体的光弯曲来获得更好的约束。
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