quantum gravity

Physicist Sabine Hossenfelder is discussing whether researchers may have found the first evidence for quantum gravity, a long-sought unification of quantum mechanics and general relativity. The claim has drawn wide attention, as no experiment has ever directly confirmed that gravity is quantised, and physicists remain divided over whether current measurement techniques could truly detect such effects.

Physicists are discussing claims that an unusual photon observation could be the first direct evidence for quantum gravity, a long-sought theory uniting quantum mechanics with general relativity. If confirmed, the detection would mark a major breakthrough, though researchers urge caution until the result is independently verified. No further details on the experiment or findings are currently available.

A rigorous re-examination of cosmic gamma-ray observations has found no evidence that Lorentz invariance breaks down at high energies. Researchers applying unified statistical methods confirmed that the speed of light remains constant regardless of photon energy or direction, reinforcing Einstein's relativity and placing tighter limits on quantum-gravity models that predict energy-dependent light speeds.

New research using cosmic gamma rays is probing whether the speed of light is truly constant, a cornerstone of Einstein's relativity. By studying high-energy photons that travelled vast cosmic distances, physicists are searching for tiny deviations that could point to quantum gravity effects and challenge the limits of Einstein's theory.

Physics World reports that graviton modes survive on the lattice, according to a new study in lattice approaches to quantum gravity. The finding suggests that gravitational degrees of freedom persist even when spacetime is modelled as a discrete lattice, a result relevant to attempts to quantise gravity non-perturbatively. Physicists are weighing what this means for theories that predicted such modes might be washed out by discretisation.