Laser cooling is a technique used to reduce the temperature of atoms or molecules by using laser light. When a laser beam is directed at these particles, it can slow them down by transferring momentum. This process lowers their kinetic energy, which corresponds to a decrease in temperature. The method relies on the interaction between the laser light and the particles' energy levels. By carefully tuning the laser frequency, scientists can selectively target specific atoms, causing them to absorb and then re-emit photons. This results in a net loss of energy, effectively cooling the particles to near absolute zero.