In classical mechanics, a special status is assigned to time in the sense that it is treated as a classical background parameter, external to the system itself. This special role is seen in the standard formulation of … See more

The quantum concept of time first emerged from early research on quantum gravity, in particular from the work of Bryce DeWitt in the 1960s:, which resulted in the Wheeler–DeWitt equation.
"Other times are just special cases of other universes." See more

The thermal time hypothesis is a possible solution to the problem of time in classical and quantum theory as has been put forward by Carlo Rovelli and Alain Connes. Physical time flow … See more

Though classically spacetime appears to be an absolute background, within general relativity time is no longer a background parameter, but must be considered on equal footing with space, and time and space evolve together as spacetime. Gravity is a … See more

Motivated by the Immirzi ambiguity in loop quantum gravity and the near conformal invariance of the standard model of elementary particles, Charles Wang and co-workers have argued that the problem of time may be related to an underlying scale invariance See more

• Hořava–Lifshitz gravity
• De Donder–Weyl theory See more

• The Order of Time by Carlo Rovelli
• Time Reborn by Lee Smolin
• The Singular Universe and the Reality of Time by Lee Smolin See more