This is is a tough one. First, it is true that time and distance (length) are continuously subject to the effects of relativity. However, at human scale these things are not noticeable in daily life. Let me try one example: the length of the meter, using physical objects. I MORE then welcome corrections!!

Assume the bureau of weighs and measures constructs a few dozen meter sticks at the same place, with the intent of installing all but one of them at railway car window level all along the the track from DC to LA. The train has a viewing port where the last stick is mounted for the purpose of comparing the moving one with those at fixed locations as the train passes.

The train is then accelarated incrementally past all the fixed locations and we compare the fixed ones to the moving one. We will notice that the faster the train goes, the shorter the stick it carries seems to be. At earthly velocities we will notice shortening on a miniscule level. In fact, the shortening is so little we need a science fiction device to do the measuring.

However, if the train goes by at about 86 percent the speed of light, the stick will actually appear to be one half the original length. In addition we also notice that the railway clock in the car is also ticking at half speed. The passengers on the train see none of this because both time and distance change in lockstep with each other.

We then gather up all the sticks and move them at road speed to LA where we compare the sticks once again. They will all be the same length. However, we also compare the railway clock with the same type we have, and notice the one on the train seems to have lost time, which is in fact, the case.

Now here is where I get stuck. I THINK the observers on the train see our sticks as having grown in length as they passed, and our clocks seem to be running faster. I THINK this is the case because the diffences in speed come about because we applied ACCELERATION only to the train. Einstien seems to have compared induced acceleration with gravitational acceleration and having similar effects.

This seems clearer to me if we extend the passenger trip into a spaceship traveling at 86 percent the speed of light to a location exactly one light year distant. We observe the spaceship arrive about 14 months later. However, something very stange has taken place.

First, the astronaut reports having arrived at the destination in about seven months. This is beccause at 86 percent the speed of light his time slows by half. Even stranger still, he has reported his location along the way using celestial navigation, and is astonished to report he seems to be travelling FASTER then the speed of light. Well he did after all, get there in only seven months by his own calculation.

So. How does all this relate to our sun being about 5 billion years old? The solar system is something of a closed system in that none of the objects in it that we can see travel anywhere near the speed of light in relation to one another. So we see our year, calculated as current orbital speed, as stable over time. And we can simply infer backwards in time with such methods as red shift telling us how fast the galaxies are recedeing according to OUR time and how we measure it in light years. After all, we are the ones looking out the train window, and we will always observe the speed of light as 300,000km/s.

However, there are some flies in the ointment. The one close to home is the orbit of Planet Mucury. It is so close to the sun's massive gravity that its orbit can only be explained using relitavistic phenomena. Another possible fly is the universe is now expand faster! Acceleative forces are being applied to us! Of course this force may be the same for all the galaxies, and does not have immediate relativistic meaning to us.

And then there are the objects most distant from us. I have read it may be possible that some objects are receding at the apparent speed of light or greater as space itself expands at relativistic speed.

All this could be entire balderdash, based as it is on very little mathematical capacity on my part. And as for the Universe after one second? Stumps me. I HAVE heard it describe in Planck Time Units, which a measure in and of themselves. But I have a headache.