Physicists Uncover Forces Behind Whirling Dervishes (Video)

Physicists have learned a bit more about the forces that power Whirling Dervishes. They've found that the physics that intricately links the rotation of the Earth with the direction of weather patterns in the atmosphere plays a crucial role in the creation of the hypnotic patterns created by these Whirling Dervishes.

The Whirling Dervishes, who have become a popular tourist attraction in Turkey, are a religious movement. They commemorate the 13^th century Persian poet, Rumi, by spinning on the spot and creating mesmerizing patterns with their long skirts. Yet it turns out that their skirts are subject to the same forces as weather patterns in our atmosphere.

This particular effect that our weather patterns are subject to is known as the Coriolis force. This force is essential for creating the archetypal, and sometimes counterintuitive, patterns seen on the skirts. The Coriolis effect accounts for the deflection of objects on a rotating surface and is most commonly encountered when looking at Earth's rotations and its effect on the atmosphere around it. The rotation of the Earth creates the Coriolis force which causes winds to be deflected clockwise in the Northern Hemisphere and anti-clockwise in the Southern Hemisphere.

"Because the sheet is conically symmetric, material can flow along its surface without stretching or deforming," said James Hanna, one of the researchers, in a news release. "You can think of the rotating Earth, for example, with the air of the atmosphere free to flow around it. The flow of a sheet of material is much more restrictive than the flow of the atmosphere, but nonetheless it results in Coriolis forces. What we found was that this flow, and the associated Coriolis forces, plays a crucial role in forming the dervish-like patterns."

In fact, the researchers were able to create equations to describe what was happening with the skirts of the Whirling Dervishes. By providing a basic mathematical description of the spinning skirts, the scientists hope that their future research will discern how different patterns are selected, how stable these patterns are and if gravity or any other effects make a qualitative difference.

The findings are published in the New Journal of Physics

Want to see the Whirling Dervishes for yourself? Check out the video below, courtesy of YouTube.