Some of the largest ocean eddies on earth are mathematically equivalent to the mysterious black holes of space, scientists say.
These eddies are so tightly shielded by circular water paths that nothing caught up in them escapes.
George Haller, professor of Non-linear Dynamics at ETH Zurich, and Francisco Beron-Vera, Research professor of Oceanography at the University of Miami, have developed a new mathematical technique to find water-transporting eddies with coherent boundaries.
The challenge in finding such eddies is to pinpoint coherent water islands in a turbulent ocean. The rotating and drifting fluid motion appears chaotic to the observer both inside and outside an eddy. Haller and Beron-Vera were able to isolate coherent water islands from a sequence of satellite observations. To their surprise, such coherent eddies turned out to be mathematically equivalent to black holes. Black holes are objects in space with a mass so great that they attract everything that comes within a certain distance of them. Nothing that comes too close can escape, not even light. But at a critical distance, a light beam no longer spirals into the black hole. Rather, it dramatically bends and comes back to its original position, forming a circular orbit. Haller and Beron-Vera discovered similar closed barriers around select ocean eddies. Here, fluid particles move around in closed loops – similar to the path of light in a photon sphere.