Vacuum fluctuations at Farmoor

 It was a very calm day at Farmoor Reservoir.

We did spot the Great Northern Diver.

It occurred to me that even on a calm day the surface of the water is not perfectly still. Looked at closely, small ripples are visible. This reminded me of the amazing discovery that a vacuum is not a smooth emptiness but is a seething mass of virtual particle pairs popping into and out of existence due to energy fluctuations based on Heisenberg's Uncertainty Principle. https://en.wikipedia.org/wiki/Quantum_fluctuation