No one knows exactly what it looks like, but some scientists believe there is a mirror universe altering gravity in our present reality.

Three academics published their findings in Physical Review Letters this week, claiming that their idea is based on issues with the Hubble Constant, the rate at which the cosmos expands. According to a SciTechDaily story on the study published yesterday, forecasts for that constant are much slower than what we’ve observed in reality, and scientists are trying to figure out why. It’s possible that the cause is a mirror world that we can’t see yet.

This could explain why there appears to be a disagreement between different measurements of the rate of expansion of the Universe.

Scientists have long constructed models of the universe. The goal now is to make one that follows all of the cosmic rules we’ve studied so far. According to the researchers, if the universe is using what we know about its physics and symmetry, there might be an invisible mirror world that is remarkably identical to ours but is only apparent due to gravitational interactions with our world.

Given that some believe the cosmos is a neural network in and of itself, and that there may even be two realities interacting with one another, it’s not the most outlandish hypothesis we’ve heard, but we’re curious to see it for ourselves.