Photo by Luana Azevedo

Alison is a PhD student in Integrative Systems Biology Lab at the King Abdullah University of Science and Technology, Saudi Arabia. Her work focuses on transcriptomic temperature and CO2 adaptations of the spiny chromis damselfish across generations. Want to know more about Alison and her work? Follow her on Twitter @AliMonroe22

Evanescent (no, not the band Evanescence!). “It is an elegant way of describing how something is fleeting or fading away,” explains Alison Monroe, sci-fi and fantasy bookworm.

The word comes from the Latin evanscere meaning “to vanish.” “I learned this word in English class. For some reason, it has always stuck with me” says Alison. In science, the word is most frequently associated with electromagnetics. Traditional electromagnetic waves travel in a synchronized manner. This means the energy of the wave is consistent over space. An evanescent wave, however, has its strongest energetic field near the interface it originates from. The intensity of evanescent waves decay exponentially with distance from their source. A way to imagine this is by thinking of acoustic waves: sound will be louder near its source and slowly fade with distance.

Interestingly, there is also an emotional evanescence. This term describes the fading feeling of pain, depression or emotional distress over time. It is suggested that emotional evanescence exists because with time people make sense of situations, reducing their emotional impact – a process also known as ordinization.

Although the word has little to do with Alison’s PhD project, she admits “I’m pretty sure I even tried to slip it into my master thesis.” If that isn’t commitment to a word, I don’t know what is! Truth be told, she didn’t know it was related to science at all. “Although as a marine biologist I’m going to guess that the ocean has lots of evanescent wavelengths” she tells us suspiciously. Indeed, waves can also be evanescent, as their force can reduce with distance.

Waves, emotions and the band Evanescence can fade; one thing that does not appear to be evanescent are the student debts…

Alisons’ example sentence:

Both dreams and money are evanescent, unless you become a billionaire.


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1 Brocas, I. and Carrillo, J. (2004). The psychology of economics, Oxford University Press, United Kingdom.