For many thousands of years man has looked up at the stars and wondered about the forces that keep them moving in their endless dance.  More recently, less than 350 years ago, Isaac Newton saw that these were the same forces that brought apples down from trees, rain down on our heads and us back down to earth when we jumped upwards.
It was just under a century ago that Einstein gave us a description of gravitation as curvature of spacetime, with massive bodies such as a planet or a star creating great dents in the fabric of the cosmos.  Smaller bodies, such as moons, satellites, even the planets themselves, roll around the inside of those dents just as an orange would roll around the inside of a fruit bowl.

Cosmologist John Wheeler paraphrased this idea in the quote given above. In 2011, for the very first and only time, a mainstream peer-reviewed journal published details of what 'curved space' might mean, how it may be that massive objects could cause that 'shaping' of space and why objects would follow those curves in the way described by General Relativity. Not even Einstein himself offered explanations for any of those effects.

Gravity has always been an enigma, with a number of questions attached to it:
(1) Why does gravity always attract, never repel like static electricity and magnetism do?
(2) Why is gravity so weak compared to those forces?
 (Only 1/1,000,000,000,000,000,000,000,000,000,000,000,000th of their strength!)
(3) How is it that the effect of gravity reaches right the way across the universe?

All of these questions, as well as those questions about what 'curved space' is and how it works, are answered by just one simple proposal, spoken of by mystics for thousands of years and supported by reams of well-established findings from top scientists, spanning more than a century. That simple proposal, presented in detail in a previous paper, is: 'All elementary sub-atomic particles are formed from photons of electromagnetic energy – light' (including non-visible frequencies).

Following his previous paper giving a radically new perspective on Special Relativity, Dr Grahame Blackwell published a follow-up paper on General Relativity in Kybernetes, the journal of the World Organisation of Systems and Cybernetics, in November 2011.

'Cosmic system dynamics: a cyberneticist's perspective on gravitation' appeared as an invited paper in the final issue of the 40th anniversary volume. Referencing over thirty peer-reviewed publications, including works from four of the world's greatest Nobel laureates, it builds on that previous paper to show how light-based particles of matter could be responsible for creating every effect that we attribute to gravitation.

See more about this paper, including extended abstract, introduction and conclusion, plus a non-technical summary.
[The complete paper, plus a straightforward non-technical explanation of its contents, are included in the book Atoms of Light.]

Footnote: In Summer 2012, the year after Dr Blackwell's ground-breaking paper which shows gravitation to be an electromagnetic effect, New Scientist published the following:
"[A]t the Complutense University of Madrid, Spain, they were playing with a particular version of a mutant gravity model called a vector-tensor theory, which they had found could mimic dark energy. Then came a sudden realisation. The new theory was supposed to be describing a strange version of gravity, but its equations bore an uncanny resemblance to some of the mathematics underlying another force. "They looked like electromagnetism," says Beltrán, now based at the University of Geneva in Switzerland. "We started to think there could be a connection." "

The abstract from the Dec 2011 arXiv paper detailing this new research refers to effects as being generated by "electromagnetic potential" - precisely as proposed by Dr Blackwell in his paper journal-published earlier that year.