Nikola Tesla's dynamic theory of gravity was an attempt to ascertain a theory between gravitational radiation and the electromagnetic force as a unified field theory (a model over matter and energy). No mathematical details of the theory are available, nor is there any evidence that Tesla ever worked them out. The most documented part is Tesla's critique of Einstein's theory of relativity - at the time of his announcement, it was considered by the scientific establishment to exceed the bounds of reason. Nowadays it is simply ignored.

The theory was developed initially between 1892 and 1894, during the period that he was conducting experiments with high frequency and high potential electromagnetism, and was never published. Though these principles guided his future research and experiments, Tesla did not announce it until near the end of his life.

Tesla published a prepared statement on his 81st birthday (July 10, 1937) critiquing Albert Einstein's theory of relativity. The following is a portion of that statement:

... Supposing that the bodies act upon the surrounding space causing curving of the same, it appears to my simple mind that the curved spaces must react on the bodies, and producing the opposite effects, straightening out the curves. Since action and reaction are coexistent, it follows that the supposed curvature of space is entirely impossible - But even if it existed it would not explain the motions of the bodies as observed. Only the existence of a field of force can account for the motions of the bodies as observed, and its assumption dispenses with space curvature. All literature on this subject is futile and destined to oblivion. So are all attempts to explain the workings of the universe without recognizing the existence of the ether and the indispensable function it plays in the phenomena...

My second discovery was of a physical truth of the greatest importance. As I have searched the entire scientific records in more than a half dozen languages for a long time without finding the least anticipation, I consider myself the original discoverer of this truth, which can be expressed by the statement: There is no energy in matter other than that received from the environment.

While this statement asserted that Tesla had "worked out a dynamic theory of gravity" that he soon hoped to give to the world, he reportedly died before he publicized the details. Few details were revealed by Tesla about his theory.

As an alternative to Einstein's general relativity, Tesla's theory was supposed to explain gravity using electrodynamics. Details of Tesla's theory that are available consist of basic arguments against space being curved by gravitational effects, which leads some to believe Tesla failed to understand Einstein's theory is not about curved space at all, but curved space-time. There is disagreement about Tesla's exact understanding of Einstein's theories, as Tesla was actively conducting his research during the time of Einstein's research.

The principles of relativity which Tesla disputed show up in very broad range of effects and have been confirmed by numerous experiments. For instance, the relativistic relation between mass and energy, which Tesla did not accept, shows up in a variety of phenomena:

• The mass deficit of atomic nuclei, i.e. that atomic nuclei weigh less than the sum of their parts
• The energy released by particle-antiparticle collisions and absorbed by particle-antiparticle pair creation (annihilation)
• The increasing inertial mass of particles in accelerators, when their velocity goes near light speed.

External links and references

• Tesla, Nikola, "Prepared Statement of Tesla". July 10, 1937. (Interview with press on 81st birthday observance; DOC format)
• The Man Who Invented the Twentieth Century: Nikola Tesla, Forgotten Genius of Electricity, Robert Lomas, Headline Book Publishing, 1999. ISBN 0747262659