Falling into Gargantua: How Tidal Forces Affect Objects Approaching the Inner Horizon of a Spinning Black Hole*

In the movie “Interstellar”, the protagonist Cooper, strapped in his spacecraft, freely falls towards the inner horizon of a large, rapidly rotating black hole called Gargantua. We examine the “tidal” forces that might be experienced by Cooper’s spacecraft due to the inner-horizon singularity of the black hole.

In our simplified model, the tidal force experienced by an object falling towards the inner horizon singularity is due to the primordial oscillations of the black hole, and the singularity is a null singularity. We simulated the effect of the tidal force on real materials. We found that the infalling object experiences finite tidal force. This means that an infalling object is not necessarily destroyed by the null singularity of the inner horizon.