Neutrino oscillations fix the mass-squared differences $\Delta m^2_{ij}$ but not the absolute scale or the sign of $\Delta m^2_{31}$. What are the absolute neutrino masses, is the ordering normal or…
General relativity describes gravity as spacetime curvature, while the other interactions are described by quantum field theory. Naively quantizing the Einstein–Hilbert action …
The measured muon anomaly $a_\mu = (g-2)/2$ has differed from some Standard Model predictions at the few-sigma level, … Is the tension a signal of new physics, or an artifact of hadronic…
For the incompressible Navier–Stokes equations in three dimensions, … do smooth, globally defined solutions exist for all smooth divergence-free initial data $u_0$ with finite…
Quantum field theory predicts a vacuum energy density that, cut off at the Planck scale, exceeds the observed value … by up to 120 orders of magnitude — "the worst theoretical…