Jeff Cassman

Back in 2001, the paradoxically high biodiversity on Barro Colorado Island inspired Hubbell to propose the groundbreaking neutral theory of ecology. Traditional ecology theory stressed the competition for niches between species. But Hubbell pointed out that species might not really matter in that equation because, in effect, individuals compete for resources with members of their… Continue reading The Key to Species Diversity May Be in Their Similarities

It was not obvious that transcendental numbers should exist. Moreover, it’s challenging to prove that a given number is transcendental because it requires proving a negative: that it is not the root of any polynomial with integer coefficients. In 1844, Joseph Liouville found the first one by coming at the problem indirectly. He discovered that… Continue reading Recounting the History of Math’s Transcendental Numbers

The jellyfish that move through the seas by gently pulsing their saclike bodies may not seem to hold many secrets that would interest human engineers. But simple as the creatures are, jellyfish are masterful at harnessing and controlling the flow of the water around them, sometimes with surprising efficiency. As such, they embody sophisticated solutions… Continue reading What Can Jellyfish Teach Us About Fluid Dynamics?

Most likely, the gravitational waves come from pairs of supermassive black holes that are spiraling around each other inside merging galaxies. But we might be seeing something else entirely, perhaps something exotic such as ruptures in space-time itself resulting from loops of energy called cosmic strings. “Finding for the first time the suggestion of background… Continue reading An Enormous Gravity ‘Hum’ Moves Through the Universe