OAM is associated with rotation of a particle about a fixed axis. The axial particle currents are encoded in the spiral phase profile of the particle’s wavefunction. The component of OAM ...

But their geographic locations aren't fixed: As the Earth's axis moves ... that would change the top's center of mass and axis of rotation, leading it to lean toward the heavier side as it ...

In fact, any mass change on Earth, including atmospheric pressure, can affect its axis of rotation ... in space — quasars — using them as fixed points of reference. For the new study ...