More on Gravity

I recently posted a picture of the femur from a huge dinosaur ... see: Femur Found in France ... and speculated whether gravity has changed over the eons. I say this because it is doubtful that an animal this enormous could live today with today’s gravity pull. Note that the largest animal on Earth now is the blue whale which survives in an environment, sea water, where it’s buoyancy helps counteract today’s gravity. And the blue whale is much smaller than the land animal represented by the femur found in France. Therefore, it seems clear to me that gravity here on Earth must have increased to a level where such a behemoth could not exist today.

Einstein’s View

The questions then persist ... how and why? Newton called gravity a force and Einstein called it a warp in the space-time continuum. Others speculate gravity comes from an elementary particle called a graviton. In order to continue this discussion further, read first: Universe Today Write-up. On the other hand, I have speculate before that gravity is a fifth dimension ... one of the seven new ones predicted to exist in string theory mathematics.

I have also opined that the amount of gravity is finite and that, during the Big Bang, not all gravity found some mass “to attach to” ... and became dark matter (an ironic term since it apparently has no mass). And that this orphaned gravity is what causing the universe to expand ... because only that attached to mass would cause the universe to contract ... as the sum of  known mass would suggest. If this reasoning turns out to be fact, dark matter and dark energy are one and the same.

How can gravity be both another dimension and a form of free-floating dark matter? This I haven’t fully figured out yet. Maybe just the difference between a dimension and the metric that measures it?

So, to return to the original speculation about the Earth acquiring more gravity over time ... which has caused our animal populations to shrink in physical size. Perhaps “dark matter” or meandering gravity, unattached after the universe was created, does continually find homes in places like Earth ... and results in higher gravity readings over the eons. Of course, this needs be occurring simultaneously everywhere ... or else the gravitational relations between celestial bodies would go awry ... which would not be good.

Afterthought: Could the tipping point and the rapid disappearance of the dinosaurs have been finally caused by too much gravity?