Hi, I want to share a theory so that someone smarter than me can explain why its not right.
An expansion on Einsteins theory of general relativity may explain how a universe measured to be expanding with expansion accellarating may infact not be. Heres how...
-we do not explain the contraction of spacetime (known as gravity) with a mysterious form of energy. So why do we need to imagine (dark) energy to explain the expansion of spacetime?.
-Gravity is not a force, its the curvature (in particular, contraction) of spacetime, Just as the perceived expansion of the universe (derived from seeing galaxies move away from us accelerating the further away they get) is not a force, but rather the curvature (expansion) of spacetime. So requires no (dark) energy.
-My theory consists of one simple speculation about natural spacetime or the shape of the fabric of the universe, that on the scale of galaxies, spacetime is not flat, but rather naturally curved in the opposite way to that of curvature from massive objects.
I will use the well known visual representation of a bowling ball on a stretched elastic sheet often used to explain the curvature of spacetime in regards to orbits to get my point across.
One observes a concave curvature of the sheet around the bowling ball. Picture a normal sized bowling ball as a representation of our sun (or typical star), now picture the sheet many millions of killometres square representing spacetime of the whole known universe, picture a slight convex curve in that sheet in its natural form rather than completely flat, this is the natural curvature of spacetime. Imagining spacetime in this way, we can explain why galaxies and galaxy clusters appear to move away from us relative to our position in the universe when they are actually following a straight path through convex spacetime the exact same way on a much smaller scale an object in orbit around a star or planet is following a straight line through concave spacetime.
The convex nature of spacetime is so slight, that on the scale of solar systems, it does not interfere with normal orbital mathaimatics, It MAY however have a measurable effect on the scale of galaxies.
If we can take data used to measure the speed and acceleration of galaxies away from us (that has been used to measure perceived expansion of the universe), we should then be able to measure the natural curvature of spacetime on the intergalactic scale.
Of course if this were the case, the universe may not actually be expanding, there for there is no dark energy required, No big bang and the age of the universe imesarable using this method.
This could also explain why objects such as Methuselah star, HD 140283 can be measured to be 'older than the universe'.
This is an incomplete and informal theory, I would love to hear others opinions on it. Thankyou for reading.