Time, absolute.

The concept of absolute time is a hypothetical model from the laws of classical physics postulated by Isaac Newton in the Principia in 1687. Although the Newtonian model of absolute time has since been opposed and rejected in light of more recent scholarship, it still provides a way to study science with reference to time and understand the phenomena of time within the scientific tradition. According to this model, it is assumed that time runs at the same rate for all the observers in the universe, or in other words, the rate of time of each observer can be scaled to the absolute time by multiplying the rate by a constant. This concept of absolute time suggests absolute simultaneity by the coincidence of two or more events at different points in space for all observers in the universe. So, absolute time has been discussed in two senses of absoluteness. In first sense, absoluteness means independent of events, while in second sense, it means independent of observer or frame of reference