We have 4 fundamental forces of nature. 'Quantum gravity' could help lead us to a mysterious 5th

For decades, scientists have searched for a fifth fundamental force of nature that can explain mysterious aspects of the universe such as dark energy and dark matter. These are pieces of our cosmos that simply can't be accounted for by the four fundamental forces we know of: gravity and electromagnetism as well as the strong and weak nuclear forces. In addition, while the hunt for this force has been ongoing, researchers have also been desperately hunting for a theory of quantum gravity . …