Peering Inside the Proton: New Detector Hunts for Unknown Forces ✛
At Jefferson Lab in the US, the spectrometer SoLID is being prepared for launch — an instrument that sorts particles by their properties. It works like an ultrafast 3D microscope: it captures the trails from collisions between electrons and protons and reconstructs the inner structure of matter.
This 'microscope' has three goals. First, to build a 3D map of the proton, where quarks — tiny building blocks — and gluons, the glue that holds them, move. Second, to measure where mass comes from. The quarks themselves are almost massless — 99% of the mass is created by the energy of the gluon field. SoLID will for the first time see the distribution of this energy. Third, the instrument hunts for particles that don't fit into the Standard Model — the best theory of the micro-world. Discovering, for instance, dark photons — invisible counterparts of light — could explain the nature of dark matter. And then it turns out: the familiar 'solidity' of matter is just an illusion, born from the energy of fields.
Without the gluon 'glue,' the proton would be almost weightless: the three quarks inside it account for less than 2% of its actual mass.
The hunt for unknown particles echoes sci-fi ideas about hidden layers of reality, like subspace from Star Trek or extra dimensions from Interstellar.