Astronomical observations show that our universe is expanding (and accelerating in that expansion) in all directions due to something we call ‘dark energy’ – but what exactly is it? There are many theories out there, and astrophysicists have an unlikely ally in the search – atomic physicists like myself. As part of my PhD research, I used lasers to trap and cool atoms to then use as tiny accelerometers to sense new physics, including a potential dark energy candidate, the chameleon field. I may have measured zero, but it turns out that that's moving science forward anyway.