It is known that the contribution of torsion to the equation for the chiral Weyl fermions can be equivalently considered in terms of the axial U(1) gauge field. In this scenario the gravitational field transforms to the U(1) gauge field. Here we show that in chiral superconductors the opposite scenario takes place: the electromagnetic U(1) field serves as the spin connection for the Bogoliubov fermionic quasiparticles. As a result the electromagnetic field gives rise to the gravitational anomaly, which contains the extra factor 1/3 in the corresponding Adler–Bell–Jackiw equation as compared with the conventional chiral anomaly. We also consider the gravitational anomaly produced in neutral Weyl superfluids by the analog of the gravitational instanton, the process of creation and annihilation of the 3D topological objects – hopfions. The gravitational instanton leads to creation of the chiral charge.

众所周知，可以根据轴向U（1）规范场等效地考虑扭转对手性Weyl费米子方程的贡献。在这种情况下，重力场将转换为U（1）规范场。在这里，我们表明在手性超导体中发生了相反的情况：电磁U（1）场用作Bogoliubov铁离子准粒子的自旋连接。结果，电磁场引起了重力异常，与常规的手性异常相比，它在相应的Adler–Bell–Jackiw方程中包含了额外的1/3因子。我们还考虑了中性Weyl超流体中由引力瞬时子的类似物，3D拓扑对象– Hopfions的创建和an灭过程产生的引力异常。引力瞬间导致手性电荷的产生。