It seems our understanding of gravity is in flux these days. This is from another scientific pair who dispute the existance of Dark Matter. For those that don’t know, when astronomers tried to apply our gravity formulas to larger bodies like black holes and galaxies the results didn’t match observed behavior. To resolve this Dark Matter was invented. This reminds me too much of the concept of ether. I like to find things that attempt to disprove it. My favorite idea is that gravity changes over extreme distances, like between stars or galaxies and is not constant. Perhaps it even changes over planetary distances. The first probes launched out of the solar system 30+ years ago are off their expected track by 400,000 miles. This seems semetrical, because of the formula for speed (velocity). In our experience on Earth speed is simply distance/time. However, in the extremely fast other factors begin to have more affect. Einstein’s equations show that mass increases the closer to the speed of light that you move and time dilation effects begin to become noticeable.
Why is this important?
I think it could lead to an improved understanding in a basic part of science. Understanding like this results in nuclear power, fiber optics, solid state circuits, radios, satellites, etc. Personally, I’m hoping for a new type of engine that would allow flying cars. 
Anyway, enough rambling…
From PP.\RC.
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A new law for gravity, developed by Dr Hong Sheng Zhao and his Belgian collaborator Dr Benoit Famaey of the Free University of Brussels (ULB), aims to prove whether Einstein’s theory was in fact correct and whether the astronomical mystery of Dark Matter actually exists. Their research was published on February 10th in the US-based Astrophysical Journal Letters. Their formula suggests that gravity drops less sharply with distance as in Einstein, and changes subtly from solar systems to galaxies and to the universe.
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They have created a formula that allows gravity to change continuously over various distance scales and, most importantly, fits the data for observations of galaxies. To fit galaxy data equally well in the rival Dark Matter paradigm would be as challenging as balancing a ball on a needle, which motivated the two astronomers to look at an alternative gravity idea.
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