This paper; https://arxiv.org/abs/1702.03050, Experimental demonstration of a fifth force due to chameleon field via cold atoms, by Zhang claims detection of yet another 5th force of nature. I recall a similar claim from last year by Jonathan Feng, et. al.; https://arxiv.org/abs/1608.03591, Particle Physics Models for the 17 MeV Anomaly in Beryllium Nuclear Decays. I am unable to discern if, or how these two claims might be linked. Apparently the force reported by Feng is thought to be related to dark matter, whereas the force reported by Zhang is alleged to be related to dark energy. Very convenient, solving both mysteries in 2 fell swoops. Almost sounds too good to be true - which is obviously a difficult impression to avoid. The Feng paper made the pop sci circuit pretty quickly. I've not yet seen any feedback on the claim by Zhang, but it would be quite surprising if it escaped notice. Perhaps one of our resident particle physics experts can shed some light on just what the heck is going on in the usually plodding world of hep.