Welcome to “Fully Relative”

A new perspective on the beautiful physics of our Universe

Einstein’s General Theory of Relativity was 100 years old in December 2015.  It has had remarkable success in explaining the gravitational behaviour of large objects from planets to galaxies.  However, the biggest challenge is that it is inherently inconsistent with the other major, and even more successful, theory of physics Quantum Mechanics. QM explains the behaviour of small objects, from molecules to atoms to elementary particles.  Other challenges lie in the picture of the Universe based on General Relativity.  It predicts black holes from which light cannot escape, because they have event horizons at which time stops. No field travelling at the speed of light should be able to cross this horizon and escape. However, changes in gravitational fields are understood and have been observed to travel at the speed of light. Yet stars and black holes can rotate around each other via gravitational attraction. They also have infinities (singularities) at their centres.  Such infinities are unphysical and at some level mean the theory is either incorrect or no longer applicable.

Analyses based on General Relativity, of observations of galaxies, have led to the need to hypothesise invisible dark matter and dark energy that account for 95% of the mass/energy of the Universe leaving only 5% for what we are made of and can see.  The evidence for both is persuasive but is indirect.  Moreover, dark energy must have the truly remarkable property of a negative pressure. It expands the distance between galaxies faster as their density decreases.  However, perhaps the most challenging suggestion is the need for an extremely rapid expansion of the early universe. This has been hypothesised to explain how the currently observed universe can be so uniform (on large scales) when gravity should destroy this uniformity.  The idea, called Cosmological Inflation has it that: “the Universe expanded by 20 orders of magnitude in the first 10 to the minus 35 of a second after the Big Bang”.  This means the whole Universe expanded faster than the speed of light.  The suggestion appears to conflict with the understanding that it would take infinite energy for even a single electron to reach the speed of light.  The solution proposed by General Relativity is that space and time are only relational and that the empty space-time between objects is expanding rather than that the objects are moving apart.  The idea that the distance between objects in a vacuum can expand without the objects accelerating or sensing the change in movement is difficult to comprehend.

A key element of General Relativity is that gravity is not a real force but is a distortion of the geometry of space and time by matter, while the local speed of light is a universal constant.  Under this theory, distortions from opposite directions cancel, so that an observer midway between two equal stars detects no change in the strength of gravity.  A uniform non-rotating surrounding shell of matter (e.g. the rest of the galaxies in the Universe) has no effect on the laws of physics inside the shell.  This is known as the Strong (or Einstein) Equivalence Principle which has the laws of physics independent of time and place and, hence, of a constant, uniform background.  This seems to conflict with experience. Distortions from opposite directions, e.g. in length, should add.  The observer midway between two stars still feels no gravity from those stars but the strength of gravity from a third object should be reduced because the space-time is already distorted by the two stars.  Such an effect is observed with weights on a rubber sheet or water-bed.  If there are more weights around the outside of the bed, then the distortion by the same weight in the middle will be less.  The speed of a wave on the sheet or bed will also be higher.

Full Relativity is a background-dependent theory that has the speed of light increasing, but the stored energy (mass) decreasing, as the density of surrounding matter increases.  The amount of energy stored as mass (m) by the same amount of matter that currently holds energy (E) decreases in line with m=E/c². This is a huge challenge to General Relativity which has mass and the speed of light as invariant quantities.

The idea that the speed of light is constant arose from observations that its speed is independent of the speed of the emitter.  Otherwise, the light from the stars of a binary system would reach us later than expected from the star moving away and earlier than expected from the one approaching.  Special Relativity changed this observation into the claim that the measured speed of light would always have the same value (in the absence of a gravitational field).  Therefore, if moving clocks tick slower, distances need to decrease if the measured value is to remain the same.  However, if the underlying speed of light is constant and distances are undistorted then light will appear to travel further per tick. This means that the concept of a linked space-time that can be distorted by matter is an illusion arising from an inversion of time intervals relative to distance intervals.  Instead, the speed of light changes with the amount of surrounding matter.

Gravitational acceleration simply arises from a reduction in the energy that can be stored by the same amount of matter when the background from other mass, and the speed of light, increase.  This simple change means that photons are not red-shifted (do not lose energy) in escaping a gravitational field.  Instead, the mass of atoms increases from the work done in raising them to a higher gravitational potential.  This has the immediate advantage of removing the singularities inside black holes because mass decreases as the density of matter increases.  It removes General Relativity’s requirement for an enormous pool of energy in a nearly empty universe that gives energy to objects as its distortion increases.  It also means that gravity can cross the event horizon of a black hole while light can be trapped by bending.

The necessary increase in the speed of light going back in time fully explains the increase in distance of the standard candles of type 1a supernovae based on brightness, relative to the distance based on redshift.  The need for an accelerating expansion, and consequently for “dark energy”, is entirely removed. Moreover, it can be shown that the faulty assumption that mass is constant necessarily leads to the expectation that empty space will appear to be a source of a repulsive gravitational energy (as per dark energy). 

Full Relativity’s background, which replaces the (background) fabric of space-time, also needs to explain inertia and the bending of light.  This is proposed to arise from almost equal contributions of opposite handedness from now separated galaxy clusters of matter and antimatter.  A local asymmetry in the amount of like matter alters both the bending and inertia.  Inertia will then increase with clumping of matter as the universe evolves, so that the redshift of galaxies arises from a steady reduction in the magnitude of the background over time.  The universe does not need to have evolved from a hot dense Big Bang, nor is there a need for the absurd concept of cosmological expansion where the whole universe expanded at an impossible speed from an initial state which would have trapped all matter inside a black hole!  The effect of background asymmetry on inertia means that the inertia within our solar system is approximately constant while it significantly decreases with distance from the centre of such an isolated galaxy.  This allows an explanation of the flat rotation curves of spiral galaxies and of the observed gravitational lensing of galaxy clusters without the need for dark matter.

The observed changes in mass and inertia of objects deduced from the supernovae data give a prediction for the change in clock-rate over time.  This means that a signal from a stable clock will actually increase in frequency over time. Observation of the change would require an earlier signal to be delayed and then compared with the current signal.  This is now possible by comparing returned signals sent to distant spacecraft.

The revised theory appears to allow all of the remarkably successful predictions of General Relativity to be reproduced while removing the need for dark energy, dark matter and cosmological inflation.  Moreover, it appears consistent with Quantum Mechanics and with the Standard Model of particle physics.  The behaviour of all objects becomes fully relative – the velocity and difficulty of accelerating objects (inertia) becomes dependent on the magnitude (stored energy), distance (with a 1/r dependence), and direction of all other objects.