Wait, there is one more fundamental force of nature waiting to be discoveredHungarian physicists discover new evidence that hints at fifth fundamental force of nature

Attila Krasznahorkay and his group at the Hungarian Academy of Sciences’s Institute for Nuclear Research in Debrecen, Hungary, initially published their new discovery last year on the arXiv preprint server. Their findings were published in January 2016 in the journal Physical Review Letters. Protons were aimed at lithium-7, a collision that created unstable beryllium-8 nuclei, which then decayed into pairs of electrons and positrons. At about 140 degrees, the number of these pairs increased, creating a little bump before dropping off again at higher angles. According to Krasznahorkay and his team, this ‘bump’ was evidence of a new particle. They calculated that the mass of this new particle would be around 17 megaelectronvolts (MeV), which isn’t what was expected for the ‘dark photon’, but could be evidence of something else entirely. The end result was a new boson particle that was only 34 times heavier than an electron. “We are very confident about our experimental results,” Krasznahorkay told Nature. However, the report was largely overlooked. Then, on April 25, a group of US theoretical physicists brought the finding to wider attention by publishing its own analysis of the result on arXiv2. The US team, led by the lead author of the arXiv report, Jonathan Feng from the University of California, Irvine, showed that the data didn’t conflict with previous experiments, and established that it could be evidence for a fifth fundamental force. “We brought it out from relative obscurity,” says Feng. The physics world is now buzzing with the possibility of an undiscovered fundamental force. Rumours about this elusive fifth force has existed for years, partly motivated by the incapability of the standard model of particle physics to explain dark matter—a hypothetical form of matter that comprises a huge portion of the mass and energy in the observable universe. Dark matter can feel gravity but not electromagnetism, which is why we cannot see or touch it, since our sight, touch, and most of our science experiments detect stuff using the electromagnetic force. The physicists who conducted the original experiment are confident about what they have discovered. Nature News article reports that other physicists seem doubtful, but are excited about the about the experimental results. Physicists are now thinking about different ways to scrutinize this intriguing finding. Researchers at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia, CERN, and other labs are trying to see if they can reconstruct the Hungarian team’s results in their own experiments. They are expected to confirm or invalidate the Hungarian experimental results in about a year.