The Duality of Time Theory

In 1917, in order to make the Universe static, Einstein first added the cosmological constantto his field equations, so that the attraction of mattermay balance the cosmological constant repulsion. This postulate was later discarded after Hubble’s observations in 1929 that confirmed the Universe expansion model that was proposed by Lemaitre in 1927. Einstein later declared the cosmological constant as the biggest blunder of his life, but the concept had been revived later in 1960s when Quantum Field Theory predicted that quantum fluctuations would make huge contributions to the vacuum energy, as we shall discuss further in section 9.21.