Donny gave us some topics that are core SOM areas for dialogue. Again, do not be mislead. I know that we HAVE to make some presumptions. It will not and does not work generally in relativistic mechanics, nor in quantum mechanics, nor in relativistic quantum mechanics. So to call it a scientific truth is a stretch unless you characterize your statement with the above just mentioned qualifications.
Acceleration is the second derivative of distance or length with respect to time.
Every one of these is a physical indefinable. None is expressible or definable in terms simpler than themselves. They are presumed terms. They are analogues. Then we would love to see your definition of length.