Last night I was thinking about how our ability to work and communicate on the go has compressed the time it takes for us to perform various tasks. To put it another way, we can get more done in a shorter period of time.

I know I'm getting into "well,duh" territory here, but hear me out. When it comes to task-related time management, we will - if not are, already - get to a point of diminishing returns.

What do I mean? Well, in technology, one way of quantifying "diminishing returns" is by positing that particular point when specific functions and applications reach a confluence with immutable laws of physics and as a result can advance no more.

Think of portable devices. They are getting smaller, but our thumbs are not. And, eventually, chip size and capacity will hit the wall, too. And there's a case to be made that nothing can be made to travel faster than the speed of light.

When it comes to using mobile devices for time management efficiencies, there's an immutable law in our path.

On this planet, we only get 168 hours a week. It was 168 hours before humans walked the earth, 168 hours when we lived in caves, 168 hours when we first built fire, the wheel, the semiconductor. And, until we establish colonies on asteroids and outer planets, this paradigm is not going to change.

Eventually, the ability of our mobile devices to help us do more is going to hit the wall. Why? Simple. The Earth, our Earth, is stuck at 168 hours. To put it another way, our planet is not scalable.