The many lives of theoretical physicist Elsie Hannaway have finally caught up with her. By day, she's an adjunct professor, toiling away at grading labs and teaching thermodynamics in the hopes of landing tenure.

By other day, Elsie makes up for her non-existent paycheck by offering her services as a fake girlfriend, tapping into her expertly honed people-pleasing skills to embody whichever version of herself the client needs. Honestly, it's a pretty sweet gig - until her carefully constructed Elsie-verse comes crashing down. Because Jack Smith, the annoyingly attractive and arrogant older brother of her favourite client, turns out to be the cold-hearted experimental physicist who ruined her mentor's career and undermined the reputation of theorists everywhere.

And he's the same Jack Smith who rules over the physics department at MIT, standing right between Elsie and her dream job. Elsie is prepared for an all-out war of scholarly sabotage but... those long, penetrating looks? Not having to be anything other than her true self when she's with him? Will falling into an experimentalist's orbit finally tempt her to put her most guarded theories on love into practice?

'Ali Hazelwood proves that science is sexy as hell, and that love can 'STEM' from the most unlikely places. She's my newest must-buy author.' Jodi Picoult

'I cannot get enough of her brand of brainy romance! Writing with an emotionally brilliant and witty pen, Hazelwood is an absolute romance powerhouse.' Christina Lauren, author of The Unhoneymooners

'Gloriously nerdy and sexy, with on-point commentary about women in STEM.' Helen Hoang, author of The Heart Principle

Proves that STEM can be sexy!' RedReaders love The Love Hypothesis:'Did I read this in 24 hours? Yes.''Funny. Snarky. Intelligent.