Galaxies in the early universe (Image: NASA, ESA, Hubble Deep Field team)

ONE of the grandest visions of physics could be a mirage. Conventional thinking has it that all the fundamental forces of nature diverged from one single force soon after the big bang. Now it seems that quantum effects may make it impossible to prove if this idea is correct.

In the 1970s, data from the Large Electron Positron Collider at CERN near Geneva hinted that the strong, weak and electromagnetic forces were beginning to converge at the energies created during particle collisions. By extrapolating this convergence to much …