## Article citationsMore >>

“The Quantum Theory of Fields”, Steven Weinberg, ISBN 0-521-55001-7.

**has been cited by the following article:**

## Article

# Projection Gravitation, a Projection Force from 5-dimensional Space-time into 4-dimensional Space-time

*International Journal of Physics*.

**2017**, Vol. 5 No. 5, 181-196

**DOI:**10.12691/ijp-5-5-6

**Copyright © 2017 Science and Education Publishing**

**Cite this paper:**

Xiao Lin Li. Projection Gravitation, a Projection Force from 5-dimensional Space-time into 4-dimensional Space-time.

*International Journal of Physics*. 2017; 5(5):181-196. doi: 10.12691/ijp-5-5-6.

Correspondence to: Xiao Lin Li, . Email: hidebrain@hotmail.com

## Abstract

A new gravity theory. Gravity is a projection force from 5-dimensional space-time into 4-dimensional space-time. The Lorentz symmetry is a projection of particle-wave symmetry from 5-dimensional space-time into 4-dimensional space-time. The gravity is an additional projection force of Lorentz symmetry. The new gravity is an extension to Lorentz symmetry. The new gravity can be seen as some kind of symmetry. Gravity only exists in 4-dimensional space-time. In 5-dimensional space-time, there not have gravity. Equivalence principle is invalid in the new gravitation. In the new gravitation, there does not have gravitational acceleration. In the new gravitation, there only have inertial coordinates, not have non-inertial coordinates. In the new gravitation, the gravity source is only the rest mass, not energy. The particle can’t be the gravity source if the particle not has rest mass. The photon not has gravity. But any particle can be affected by gravity. The photon is affected by gravity also. The gravitational mass is only equivalent to the rest mass. Under approximate weak gravity and approximate circular orbit condition, the new gravitation is equivalent to the General Relativity. The four classic experimental tests, the deflection of light by the sun, the precession of mercury, the red shift of light by the sun, the radar echo delay, are experimental tests to the new gravitation also. But even under approximate weak gravity condition, if the orbit is not approximate circular, if the orbit has higher eccentricity, there exists obvious difference between the General Relativity and the new gravitation. This difference can be a experimental test to distinguish which one is more realistic. The space-time is flat in the new gravitation, not is curved. In the new gravitation, the energy is conserved. The new gravitation is simpler than the General Relativity. In the new gravitation, the photon’s equivalent gravitational acceleration is twice of the acceleration in Newton Gravitation. In the new gravitation, there not exists black hole, but exists empty hole, and not exists space-time singularity and energy singularity. The new gravity has obvious scale effect. The new gravity has the scale factor. In gravity field, the scale factor determines the quantization results of particle’s motion. The new gravity perhaps is a force that inhibits the uncertainty of macroscopic objects. The new gravitation can derive out the result of the Planck Energy.

## Keywords

new gravitation, 5-dimensional space-time, particle-wave symmetry, Lorentz symmetry, projection gravity, rest mass, gravitational mass, General Relativity, equivalence principle, Newton Gravitation, flat space-time, inertial coordinates, approximate weak gravity, approximate circular orbit, eccentricity, deflection of light, precession of mercury, red shift of light, radar echo delay, black hole, empty hole, gravitation quantization, scale effect, scale factor, Planck Energy