I'm still not sure how acceleration can not be an absolute. I could accelerate (in space) from a particle at 3ms-2, therefore the seperation would widen at 3ms-2 and so the particle could in effect be accelerating from me at 3ms-2. The only reason i feel g when i accelerate in a car is because of the acceleration of me with repect to the back of the seat. "feel" is only our measure of something else. That something else could be doing as much as we do. I assume acceleration is a nice thought to pick on because if velocity is constant the time change would be inverse to the acceleration. i.e. when we accelerate time slows down. The statement also doesn't quantify (for me) why the return journey does not reverse the "aging" phenomena.
Ok, this is another confusion I am having. My understanding of relatvity is largely based on what it says on the tin, i.e. relativity...how i observe something relative to someone else/another frame of reference. But from the way others have spoken in threads, relativity is about a physical phenomena where clocks are literaly slowed down. Can we confirm if relativity is an apparent difference in measurement between two parties, or a literal/physical effect on the object/measuring instruments themselves. For example, if I tied a bit of string to the needle of a tachometer and pulled it, that is a physical effect on the measurement. If two parties read the needle at different angles, they would be different due to parallax, what I call an apparent measurement.
Agreed, there is a difference in reference to time dilation formulae. But what is the basis of these formulae. Is it because of a literal effect on the atoms in the clocks, or is it an apparent difference due propagation between an event happening and it being observed. If it is literal (physical) effect, doesn't this then indicate that this is a physical property and not that time itself is changed.
What I am relating to, in particular with gravitational dilation, is how can we assess the integrity of the elasticity within the atom due to changes in the gravational field, heat, vibration, etc. Is this not physical effects put on to the atoms not time.
Quite simply, is relativity apparent (i.e. the way we measure) or physical (i.e. the way the thing being measured actually changes)?
Finally, on the point of pigs. I hate big heads myself but if you sit back sometimes they spur a moment of thought. And don't forget people used to think the universe revolved around the earth, the earth was flat, that when you tied someone to a chair and held them underwater they'd drown if they were a witch. Who really knows what's right and what's wrong????