Yea, it has been quite some time since the opening of this blog, but life gets busy from time to time..

Time is an interesting concept either way! You always happen to have far to much of it, while having no idea what to do. On the other hand, it’s always short if a deadline comes close. That’s probably not a scientific discovery, but just the result of my bad planning. Either way, time is a very interesting topic we rarely think about, yet it surrounds us ‘all the time’.

The first question that jumps into my mind when thinking about the universe is ‘when did it start?’. What a nasty question! If we consider time being part of our universe (and why shouldn’t we consider that) the question includes ‘when did time start?’. And that’s where the trouble starts! To define a certain point in time (that’s what ‘when did time start?’ should return) we require something to measure it. A clock like in the lower right of your desktop won’t do, as our clocks count time distances from a certain start. We could try to do that backwards.. so lets t_start be the first moment in history, aka the first moment our universe did ever had. Then t_kickoff would be the moment where time started.. the moment before the first moment.. wait a minute!

Yea, a question that can really get you a headache. That’s cause we are bound to our used universe. For us, time is a quite boring thing. It always moves in one direction and it always has a point, called ‘now’, that is very different from all others, no matter if they are behind or in front of us. Therefore the question about “what was before?” is very natural for us. It’s easier to imagine hidden 5th and 6th dimensions, then thinking about a universe without time. But, if you put it straight, the question about ‘What was before time started?’ is nothing we will ever be able to catch, as there is no before. That’s a basic point of our modern science: We will never know it all. We can try to come as close to the thing we recognize as reality as possible, but we will never reach it, just like the poor hyperbole.

Okay but enough with this metaphysic tinkering. Let’s build our own time! For example, if developing a game engine or a simulation. As soon as our product description includes the devastating word ‘real-time’ we will have to think about how to kick of our own universe. Our objects might one day ask themselves ‘What was before the compile process?’ but that’s another question.

A common approach to build time in simulations is to slice it down into smaller pieces, called cycles. Each cycle marks a unique moment in time, and we use the (real-)time between two cycles to compute the (simulation-)time and the changes happening to objects. As developers are always low on resources, we have to think about what to do if our simulation gets too complex to deliver acceptable cycles per second. There are two solutions: either keep the (simulation-)time constant between to cycles, or use the elapsed (real-)time as the length of the current cycle in (simulation-)time. The first option allows us endless precision, at the cost of variable (simulation-)time. The second option grants us constant (simulation-) time, but we have to cut down precision, as the workload per cycle will increase the longer the cycle (simulation-)time spans become.

Yea, time is a tricky thing to think and work with, but it’s fun playing around with it. Almost as interesting as the universal switch that made everything possible: causality, but I think we will talk about that once we have a bit more time. Nasty wordplay isn’t it?