Science has different theories why some couples fall in love with each other. The Yale professor Nicholas Christakis tells about the first encounter with his future wife in the TIME KNOWLEDGE podcast - and explains the state of love research. Online dating changes the mating behavior - and also the research questions: Is there love at first click?

Other topics:

  • Where to go with the plastic? The Germans consider themselves world waste recycling experts, but the country is far away from a circular economy. A new advertising campaign is intended to improve the garbage collection ethics - but it actually hangs in a completely different place. Beware, this report from the waste sorting plant could change your kitchen.
  • And: "Tiny Houses" are the dwarven houses for the better of the world. They are as small as other people's living rooms. And where is the toilet? TIME KNOWLEDGE was visiting.

All episodes of How do you know that? , the TIME KNOW Podcast, can be found here.