Is time a property, a dimension of memory?

Time is that which separates the past and future and its the cycle of darkness with Light,

When the past and future are united then time is no more, neither will darkness be seen.

We can imagine a time before the beginning of the universe, but that doesn’t mean time existed then.

@laureth A time before time? =/

Does someone who lost his/her memory perceive (the lapse of ) time?
Has anyone experienced this condition?

Some people argue that time is out there and measurable. Others say that time is not out there; instead it is a human construct that we created to help us keep track of the world. In other words, we create time in our heads.

More about the reasons for these different views can be found here.

I’m more inclined towards the anthropocentric view of time. It’s something we created for our own convenience, like other measurement systems such as kilometers or ounces or watts.

I believe that the current thinking is that we exist in a 4-dimensional universe of spacetime. In this view, time is part of the fabric of the universe.

Here is a Discover magazine article http://discovermagazine.com/2008/apr/25-3-theories-that-might-blow-up-the-big-bang on some alternative theories to the Big Bang that offer some interesting views of time.

Note: I tried creating a Fluther type link but for some reason it was not working.

Time is also deeply related to entropy. I believe the consensus is that entropy’s tendency to increase actually defines the “arrow of time.” We think the past is the past because it’s the point in spacetime with lower entropy than the present or future.

Entropy, FYI, is often characterized as “disorder,” but it’s actually more subtle than that. A better way to think about entropy is that it’s number of ways X can be arranged without fundamentally changing it. For example, if X is a pile of rubble, it has high entropy. You can re-arrange the individual pieces of rubble however you like and it will still ultimately be a pile of rubble. But if X is a functioning skyscraper, then it has low entropy. There are only a few ways to arrange the pieces of a skyscraper so that the end result is a working skyscraper. Likewise, there’s only one way to arrange an egg so that it’s a whole egg with a shell and a yolk, but there’s a huge number of ways to arrange a broken egg. So the broken egg has higher entropy. Entropy tends to increase simply because of the laws of probability. And this tendency to increase defines our perception of time, because all of life’s processes (including consciousness) are piggybacked onto the increase of entropy.

Also: on the most fundamental level (of quantum mechanics) there is absolutely no difference between past and future. We know the equations for what happens when two particles collide. You can run the equations backwards and it looks exactly the same.

Picture a movie of gas molecules bouncing around in a box. Now run the movie backwards. They will look basically the same; you won’t be able to tell which movie is going forwards in time, and which movie is going backwards.

Antiparticles actually move backwards in time. A positron—the antiparticle of an electron, with a postive charge instead of a negative charge—moves backwards in time, just as electrons move forwards in time. “Backwards” and “forwards” are from our perspective here, of course.

Even weirder, photons don’t move through time at all—from their perspective. A photon travels at the speed of light. From our perspective as slowed-down matter, it does take time for a photon to get from A to B. But if you were a photon, you would experience both points A and B simultaneously. No time would take place on your journey.

So the subjective experience of time must have something to do with matter and the accumulation of mass, along with entropy. There’s been a lot of work connecting entropy to mass and gravity, too (the three laws of entropy—thermodynamics—are basically identical to three laws concerning the mass of a black hole).

Time is an abstract concept created by mankind to measure the unmeasurable.