Can a gravitational theory thought only with spatial dimensions be physically "solid" ? If Alain Aspect’s experiments on “quantum non locality” are credible, the answer could be positive. One of the more surprising thing of the microscopic world is that subatomic particles can spread information instantly regardless of their distance. This phenomenon is known also as “quantum entanglement”.
Quantum entanglement, also called the quantum non-local connection, is a property of the quantum mechanical state of a system containing two or more objects, where the objects that make up the system are linked in a way that one cannot adeguately describe the quantum state of a constituent of the system without full mention of its counterparts, even if the individual objects are spatially separated. This interconnection leads to non-classical correlations between observable physical properties of remote systems, often referred to as nonlocal correlations. The property of entanglement was recognized as a consequence of quantum theory during its formation. Quantum entanglement is at the heart of the EPR paradox that was developed by Albert Einstein, Boris Podolsky, and Nathan Rosen in 1935, and was experimentally verified for the first time in 1980 by the French physicist Alain Aspect.
An interesting interpretation of quantum entanglement is the David Bohm's one. One of the fundamental ideas of Bohm’s theory is objective dualism wave/particle : every elementary atomic object is seen as constituted by a wave and a particle at the same time, with the wave that has the job to drive the particle in the regions where the “wave function” (that is the mathematical being with which is described in quantum theory the state of every physical system) is more intense. In other words the movement of particles is not casual but driven by an “hidden field” that is the quantum potential able to determinate the trajectory of the particle. Therefore, in Bhom’s opinion, subatomic particles, that seem us separated in reality are linked in a lower level that is an “implicit order”. Then the consideration that time is not a physical being, but only the human measure of matter state variation could drive us to conclude that the fundamental level of reality is an “a-temporal” space. This perspective could explain the instantaneous communication between particles and why two particles generated by the same source remain linked as the photons of Aspect’s experiment. It is common to think that the force that takes us with feet well planted on the ground is attractive. By the other hand Newton’s law is confirmed by Keplero’s kinematic. Yet since 1916 General Relativity, today universally acknowledge as “The” gravitational theory, assumes that gravitational acceleration field due to presence of a mass in the space is caused by a local distortion of space – time around the same mass. So “ubi major minor cessat”. But it is not enough. If time is not a physical being how can it dilate or contract ? And some more, why to force space time distortions, due to a gravity field, being absolute and not relative, that is that, in reality, they are only measures done from other reference systems (inertial in SR not inertial in GR) ?
Then it's so crazy to think about a gravitational theory with only spatial dimentions ?
Marius inquires into this direction.