There’s endless debate among cosmologists about what really makes up the emptiness of outer space, though many believe that mysterious stuff that we now call dark matter and dark energy represent a significant portion. In a new yet-to-be-peer-reviewed paper flagged by Live Science, a researcher at the Indian Institute of Technology in Jodhpur named Muhammad Ghulam Khuwajah Khan proposes an intriguing theory: that space is something akin to a viscous fluid, like a slow-moving honey. The energy density of space is known as the cosmological constant, written as the Greek letter Lambda or Λ, and is considered an unchanging quality. Khan’s theory, an attempt to reconcile this mismatch, posits that we should instead mathematically treat outer space as a viscous, stretchy fluid that can contain a quality he calls “spatial phonons,” or vibrations emitted by atoms — which create waves of tension in space. But more data from these dark energy surveys will be needed to see if this theory can hold up or confine this wacky idea to the dustbins of history.