The 'Arrows Of Time' Through Systemic Functional Linguistics

Davies & Gribbin (1992: 127):

To summarise the story so far, there seem to be at least three different arrows of time in the Universe: thermodynamic, cosmological and gravitational. Almost certainly they are linked in some way. … Whatever the resolution of the puzzle of the origin of time's arrow, there is no denying that there is an arrow, and that this provides a distinction between past and future.

Blogger Comments:

From the perspective of Systemic Functional Linguistic Theory, time specifies the location and extent of processes. Applied to physics, time is the dimension along which the unfolding of processes is measured, in terms of their location and duration.

The arrow of time, from this perspective, is simply the direction of the unfolding of a process along this axis, and the different types of 'arrows' are the different types of processes that unfold. That is, the notion of an 'arrow of time' confuses the unfolding of processes with the temporal dimension by which processes are measured.

To be clear, past and future are distinguished as the time, location and extent, before and after the time of a process of making meaning, sensing or saying.

The Cosmological Expansion Through Systemic Functional Linguistics

Davies & Gribbin (1992: 107-8):

How, indeed, do we know that the Universe is expanding? The most direct evidence comes from examining the quality of light received from distant galaxies. It was found by Hubble and others that this light is systematically shifted from the blue towards the red end of the optical spectrum. This means that the light waves are stretched somewhat compared with light from similar sources (the same kinds of atoms) in laboratories on Earth. Such a 'red shift' is a familiar sign to physicists on Earth that the source of light is moving rapidly away from the observer, and this is how Hubble interpreted it. He concluded that the galaxies are rushing apart at great speed.

Blogger Comments:

From the perspective of Systemic Functional Linguistic Theory, the General Theory of Relativity models the cosmological expansion as the relative expansion of space intervals and the relative contraction of time intervals. 

Also from this perspective, the wave-particle duality of Quantum Theory is the duality of potential and instance, such that wave probabilities are instantiated as the statistical properties of particles.

On this basis, the "stretching of light waves" (red shift) in the cosmological expansion is actually the relative expansion of the space intervals between the photons of a given frequency.

On the other hand, the "stretching of light waves" (red shift) due to the motion of a light source away from an observer is the resultant increased distance between photons created by the direction of motion, independent of any expansion of the space intervals by which the distance is measured.

That is, the expansion of space is independent of motion through space. The cosmological expansion is not the motion of galaxies through space. Some galaxies are moving away from each other, some are moving toward each other. Whatever the motion of galaxies, the cosmological expansion means that the space in which all galaxies are located is expanding.

Gravitational Waves Through Systemic Functional Linguistics

Davies & Gribbin (1992: 87-8):

The idea that space and time can be distorted by motion was extended to include the influence of gravity, so that the presence of matter in spacetime would also cause distortions, or warpings, of space and time. … And as gravitating objects move about, so the space and time warps that they produce must also change. It is even possible to set up ripples in spacetime, gravitational waves that travel with the speed of light.

Blogger Comments:

From the perspective of Systemic Functional Linguistic Theory, the General Theory of Relativity models gravity as the relative contraction of space intervals and the relative expansion of time intervals. So as a gravitating body moves about, the contraction of space intervals and expansion of time intervals towards its centre of mass move about with it.

On this basis, gravitational waves are propagations of space interval contractions and time interval expansions through space-time.

The Curvature of Space-Time Through Systemic Functional Linguistics

Davies & Gribbin (1992: 84-5):

In a sense, the curvature of starbeams passing near the Sun can be regarded as a direct probe of the curvature of space. But it is important to appreciate that the curvature involves spacetime, not just space. The Earth follows a closed, elliptical orbit around the Sun, and on first acquaintance with general relativity it is natural to guess that this means the planet is following a path through curved space dictated by the gravitational field of the Sun. …

Viewed in spacetime, the Earth's orbit is not a closed ellipse, but a shape like a coiled spring, or helix. After each orbit of the Sun, the Earth returns to the same place, but to a different time, advancing one year along the time 'axis' for each orbit around the Sun. …

So the correct image of the Earth's orbit in terms of curved spacetime is a very shallow curve, weaving around the line that represents the path of the Sun through spacetime.

Blogger Comments:

From the perspective of Systemic Functional Linguistic Theory, the General Theory of Relativity models gravity as the relative contraction of space intervals and the relative expansion of time intervals with increasing proximity to a centre of mass. Because of this contraction, the shortest distance between two points — the geodesic — near a centre of mass will be towards that centre of mass, which means that the trajectory of a body in the vicinity, unless acted upon by another force, will be curved towards that centre of mass. 

Accordingly, the curvature of starbeams passing near the Sun is indicative of contracted space intervals, not curved space, and it is the trajectory of the Earth around the Sun that is curved, not space.

By the same token, the helix in Figure 17 is not the curvature of space-time, but the curved trajectory of the Earth through space plotted against time. The non-curvature of space-time is represented by the non-curvature of the space and time axes in Figure 17.