Time cannot exist without space, and the existence of time requires energy. Time is a human construct, and time is the 4th dimension, and it is a line going from the past to the present to the future.
The Arrow of Time: The arrow of time is the one-way direction or asymmetry of time. There is no way to reverse an increase in the total entropy after it has occurred. The second law of thermodynamics states that in an isolated system, entropy increases with time. Time is an illusion of consciousness, and it’s an emergent quality of space.
There are three types of time arrows: psychological arrows (underpinning our memories and how we imagine the future). A thermodynamic arrow (the direction in which entropy increases) and a cosmological arrow (the direction in which the size of the universe grows). There are many more disordered ways to arrange something than ordered ones, and change causes the disorder. General relativity tells us that what we call space is just another feature of the gravitational field of the universe, so space and space-time can not exist apart from the matter and energy that creates the gravitational field.
In quantum mechanics, time is an external classical concept, and it derives time from quantum mechanics. Entropy was extremely low right after the Big Bang. The universe started orderly, with a minimal asymmetry between time forwards and time backward. Forward won out, for now. In an open system, entropy can decrease with time.
Just because a clock measures time doesn’t make it real, the flow of information and energy are moving across time.
We represent most things in physics as fields, continuous functions defined over space and time. There are electromagnetic fields, matter fields, strong and weak fields. These fields have a ground state, a state in which they exist at their lowest energy level.
According to theoretical physicist Carlo Rovelli, time is an illusion: our naïve perception of its flow doesn’t correspond to physical reality. He posits that reality is just a complex network of events onto which we project sequences of past, present, and future.
We will no longer consider time an illusion once we have the complete picture. Time, right now, is mysterious. We link time to space, and we then call the flow of time an illusion. Stupid is as stupid does.
Now is a cognitive illusion and a mathematical trick related to how we define space and time quantitatively. One way of seeing this is to recognize that the present notion, which we sandwich between past and future, is simply a helpful hoax. Yeah, right? Stupid is as stupid does.
