Physicists propose using the Higgs boson to test whether quantum information can travel faster than the speed of light.
April 1, 2026
Original Paper
Higgs Boson Spookiness: Probing Quantum Nonlocality with Spacetime-Resolved $H\rightarrowτ^+τ^-$ Decays
arXiv · 2603.28868
The Takeaway
By measuring how Higgs particles decay across specific distances at a particle collider, researchers can test if entangled particles communicate at superluminal speeds. This would be the first time scientists have used the 'God particle' to probe the speed limit of reality itself.
From the abstract
We demonstrate that a future precision $ee$ Higgs factory would be able to perform a spacetime-resolved test of quantum nonlocality in Higgs boson decays. In simulated $ee\rightarrow ZH \rightarrow (\mu\mu)(\tau\tau)$ events at $\sqrt{s}=240$ GeV, we reconstruct $\tau$ lepton decay vertices and measure spin correlations as a function of the spacetime interval between the two $\tau$ decays. Such a measurement would be able to test Bell-inequality-violating correlations for spacelike-separated dec