The lowest temperature ever recorded in the universe is approximately 2.725 Kelvin, which is known as the cosmic microwave background radiation (CMB) temperature. The CMB is the remnant thermal radiation from the Big Bang, the event that is believed to have created the universe. It is a faint glow of microwaves that fills the entire universe and provides important insights into the early stages of its evolution. This extremely cold temperature is a reflection of the conditions shortly after the Big Bang, when the universe was very hot and dense. As the universe expanded and cooled, the CMB radiation became stretched and redshifted, resulting in its current low temperature.