Add to ORKGThough time is a ubiquitous concept in life, the basis for the direction of the flow of time remains one of physics\u27 greatest unsolved mysteries. In order to gain insight into the nature of the beginning and end of the universe and the transition between these two states, I examine four proposed fundamental arrows of time in detail. As background, I examine the theory of relativity\u27s implications for the meaning of time and provide a history of timekeeping. The thermodynamic arrow of time, which is based on the second law of thermodynamics, is described and critiqued. Next, I scrutinize the radiative, quantum, and the cosmological arrows of time. While the identity of the true fundamental arrow remains unknown, I make the case for a m...