Detached circumplanetary disks are unstable to tilting as a result of the stellar tidal potential. We examine how a tilted circumplanetary disk affects the evolution of the spin axis of an oblate planet. The disk is evolved using time-dependent equations for linear wave-like warp evolution, including terms representing the effect of the tidal potential and planetary oblateness. For a disk with a sufficiently large mass, we find that the planet spin quickly aligns to the misaligned disk. The tilt of the planetary spin axis then increases on the same timescale as the disk. This can be an efficient mechanism for generating primordial obliquity in giant planets. We suggest that directly imaged exoplanets at large orbital radii, where the disk mass criterion is more likely to be satisfied, could have significant obliquities due to the tilt instability of their circumplanetary disks.

由于恒星潮汐势，分离的环行星盘对倾斜是不稳定的。我们研究了倾斜的环行星盘如何影响扁球行星自旋轴的演化。该圆盘使用时间相关方程进行线性波状扭曲演化，包括代表潮汐势和行星扁率影响的术语。对于质量足够大的圆盘，我们发现行星的自转很快与未对准的圆盘对齐。行星自转轴的倾斜然后在与圆盘相同的时间尺度上增加。这可能是在巨行星中产生原始倾斜的有效机制。我们建议直接对大轨道半径的系外行星成像，在那里更可能满足盘质量标准，