The air in a cinema contains a chemical cocktail emitted by the audience - and the emotional tone of the movie influences the molecular composition of the cloud. That's according to a striking set of results from researchers Johnathan Williams and colleagues who took air samples from two 230-seater screens of a cinema in Germany over a period of two weeks.
Here's an example of the chemical trace associated with shows of the movie "The Hunger Games 2: Catching Fire", featuring three chemicals - carbon dioxide (CO2), acetone and isoprene. It's obvious that levels of all three increase over the course of the movie, as they accumulate in the air from all the people in the audience:
But more interestingly, we also see two peaks in the level of CO2 and isoprene towards the end of the movie. These peaks turn out to correspond to two especially tense moments in ...
