In this paper strong experimental and observational evidence is advanced for an ever expanding universe through an emerging paradigm shift in physics for the solution of hard problems such as dark-matter. The paradigm shift, in the form of a novel motion-retention theory (MRT), was revealed through a time-complementary duality principle (TCDP) of physics, first surfacing in optimum stochastic control in 1960. MRT transforms time-reversible motion theories solved with certainty initial state vectors, like Newton’s laws and Einstein’s relativity, into time-irreversible motion theories since uncertainty initial state vectors are now assumed. This, in turn, gives rise to the solution of motion problems by considering two time-complementary windows of time for their solution. One of the windows deals with the past, where uncertainty state vectors are retained and the other deals with the future where certainty state vectors are derived through motion theories that depart from estimates of uncertainty initial state vectors. In the future window of time, the motion of a discovered quantum of mass in gyration, named gyrador, occurs that is the average mass of a medium’s dissimilar cells, such as human cells or the monatomic atoms of the Sun as demonstrated in E. H. Feria (234 Meeting of AAS). On the other hand, the past window of time will address the retention of thermal-energy that is stored in the medium’s uncertainty microstates whose disorder is measured by the medium’s entropy. A discovered quantum of thermal energy, named thermote, denoting the quantum of thermal-energy due to the degrees of freedom of the medium, will fuel the kinetic energy of the gyrador, where the orbiting speed of the gyrador is found by equating the total kinetic energy of the gyradors to the gravitational potential energy of the medium. In this way a gravitational quantum expression emerges, named the gyrador mass equation (GME), found to reject dark-matter, and thus offering strong evidence for an ever expanding universe where dark-energy is unopposed (D. Overbye, NYT, Jan. 14, 2020). Another strong evidence for an ever expanding universe is the indication that its number of thermotes, equal to the universe’s fixed mass-energy over the thermote’s thermal-energy, increases with entropy as shown for black-holes and photon-gases in E.H. Feria (230 Meeting of AAS). This number of thermotes increase, in turn, reveals that a likely energy source for the universe’s expansion is the thermote’s thermal energy lost as the universe’s entropy increases with time.