elementary charge

Water in a glass looks continuous, but it's actually a dance of trillions of molecules constantly breaking and forming bonds. Seeing this dance in full detail was previously impossible: accurate calculations that account for the quantum properties of electrons could only handle tiny droplets of a few hundred atoms. The new model UBio-MolFM changes the game.

A carousel doesn't just spin you around in a circle — with each revolution, it also slightly screws itself into the ground. This corkscrew-like motion is the essence of the NUT charge, a special property of spacetime that physicists have been studying since the mid-20th century.

The weak equivalence principle, silently tested since the time of Galileo and laid at the foundation of general relativity, states: all bodies fall equally, regardless of their internal composition.

A coin landing on its edge is about as rare as a heavy B meson decaying into a light pion and an electron-positron pair. Over a decade of collider operation, only a handful of such events have accumulated, but physicists have finally managed to spot them. The decay probability is about 2.4×10⁻⁸.

Cosmic rays are particles that arrive from deep space. When such a particle hits the atmosphere, it triggers a whole shower of new particles, like a billiard ball breaking a rack, sending balls scattering in all directions. To predict what such a shower will look like, we need to know how the primary particle interacts with the nuclei of air atoms.

The nucleus of deuterium, or the deuteron, can be pictured as a microscopic spinning top. If its charge distribution is not perfectly symmetric, then in an external electric field this top experiences a minuscule tilt of its spin axis.

The hydrogen atom is like a tiny clock, ticking with a precision engineers can only dream of. When an electron jumps between orbits, it absorbs or emits light at a strictly defined frequency: that's the 'tick.' In the new work, physicists caught one such transition, between the 2S and 6P states, and measured its frequency with an…

At Hungary's Institute for Nuclear Research, ATOMKI, physicists noticed something odd: in the decays of excited atomic nuclei, pairs of electrons and positrons sometimes fly apart at an unusual angle. It's as if an invisible mediator particle briefly appears and disappears between them.

An electron beam strikes a proton like a billiard ball hitting another ball. But between them is no empty space: the particles exchange virtual photons and Z bosons, like players passing a ball behind their backs. This exchange slightly alters the scattering trajectory, and hidden within it is a hint of new physics.