Dispute accuracy of "History" section
Dispute accuracy of article
The claim in the "History" section, introduced by User:156.61.250.250‎, that GMT is defined as UT1, is not true.

As Bernard Guinot writes in the abstract of his paper, "The International Conference held in 1884 at Washington defined a universal time as the mean solar time at the Greenwich meridian (GMT). Now, the Universal Time, version UT1, is strictly defined as proportional to the angle of rotation of the Earth in space. In this evolution, the departure of UT1 from GMT does not exceed one or two seconds." Clearly there cannot be a departure between two time scales if they are defined to be the the same.