How do you think about time? Most people experience it as Newton described it—as something that passes independent of other events, that’s the same for everyone, and moves in a straight line. Still, others have come to embrace Einstein’s view that time instead forms a matrix with space and acts like as a substance in which we are submerged. But physicist and author Carlo Rovelli has an even different approach to time. He’s working on a way to quantify gravity in which time doesn’t exist.

An adult African elephant can weigh as much as two tons. Their activities—walking, playing, even bellowing—might shake the ground beneath them. But new research finds that the signals from an elephant’s walk are capable of traveling as far as three kilometers, while a male elephant might be detectable a full six kilometers away with just seismological monitoring tools. This new research could protect endangered elephants from poaching.

The E. coli outbreak linked to romaine lettuce has now spread to 29 states, and it’s claiming more victims. The CDC now reports that 149 people have been infected, more than a dozen have developed kidney failure, and one victim has died. In this segment, Ira talks with Rachel Noble, a molecular biologist at the University of North Carolina, about current methods of testing farm fields for pathogens like E. coli, which can take 24 to 48 hours to show results, and a DNA test Noble has developed that could cut that to less than an hour.

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Does Time Exist, Elephant Seismology, Produce Safety. May 11, 2018, Part 2