Trump admits he ‘often’ regrets tweets, retweets get him ‘into trouble’, in interview with Barstool Sports founder

2020-07-25 Joseph A. Wulfsohn

“Do you sometimes — because I follow you on Twitter and I know I do this… do you ever tweet out and be like — you wake up and, ‘Aw man, I wish I didn’t send that one out’?” Portnoy asked.

“Often, too often,” Trump responded. “It used to be in the old days before this, you’d write a letter and you’d say this letter is very big. You put it on your desk and then you go back tomorrow and you say, ‘Oh, I’m glad I didn’t send it,’ right? But we don’t do that with Twitter, right? We put it out instantaneously, we feel great, and then you start getting phone calls — ‘Did you really say this?’ I say, ‘What’s wrong with that?’ and you find out a lot of things.”

Behind the dead-water phenomenon

2020-07-06 CNRS

What makes ships mysteriously slow down or even stop as they travel, even though their engines are working properly?

…In 1904, the Swedish physicist and oceanographer Vagn Walfrid Ekman showed in a laboratory that waves formed under the surface at the interface between the and freshwater layers that form the upper portion of this area of the Arctic Ocean interact with the ship, generating drag.

This phenomenon, called dead water, is seen in all seas and oceans where waters of different densities (because of salinity or temperature) mix. It denotes two drag phenomena observed by scientists. The first, Nansen wave-making drag, causes a constant, abnormally low speed. The second, Ekman wave-making drag, is characterized by speed oscillations in the trapped boat. The cause of this was unknown.