Today's concept of time traces back to Albert Einstein's theories of special (SR) and general relativity (GR). In SR, uniformly moving clocks are slow with respect to my clocks. In GR, clocks in a more curved spacetime are slow with respect to my clocks. Many physicists anticipate that GR has an issue as it isn't compatible with quantum mechanics. Here we show: "Einstein time" (Einstein's concept of time) has an issue because it takes the proper time of an observer as the fourth coordinate of all objects in the universe. We replace Einstein time with "Euclidean time", which takes the proper time of an object as its fourth coordinate. SR and GR work very well as long as we describe the world on or close to Earth. Only then does time flow in one direction for all objects. In all other cases, we must take a 4D vector "flow of time" into account. Unlike other models of Euclidean relativity (ER), we claim that reality is formed by projecting 4D Euclidean spacetime (ES) to an observer's 3D space. We prove: The Lorentz transformation is recovered in ER; gravitation relates to a rotation in ES; ER is compatible with quantum mechanics. We solve 13 mysteries, such as time's arrow, mc², Hubble's law, the Hubble constant, the wave–particle duality, and quantum entanglement. Four concepts of physics (cosmic inflation, expansion of space, dark energy, non-locality) turn out to be redundant. We conclude: As ER outperforms SR and GR, Occam's razor knocks out Einstein time.