A philosopher’s guide to cosmology.

Introduction

This paper supports discussions on the quest for a new quantum theory combining the general theory of relativity and quantum mechanics. The former can make accurate predictions but the latter only probabilities. Hence, they can’t both be right, so some form of modification is necessary.   

But to do this topic justice it’s advisable to examine the early history and ensure everyone is on the same wave length. That's  my aim to avoid contradicting previously established outcomes unwittingly through a lack of familiarity.
Of course any errors on my part will need to be corrected. Along the way I will talk about theological implications and time.       

The theory surrounding quantum mechanics, on numerous counts has been (other than the laws of large scale physics relating to the the general theory of relativity) validated to govern all other known forces in the universe. Later on I explain why this  garners a hope of a richer theology; a freedom to share in creation or at least bear some responsibility in this earthly experience.      

Einstein’s genius and the evolution of ideas.   

Einstein, in 1905, developed his special theory of relativity arising from Maxwell’s previous work on electromagnetism. What had been discovered was the force of an election attracted a photon and the emergent equations gave expression to this. Einstein’s first work was to show how gravity worked in relation to electromagnetism.

By way of background, in the 1800s, it had been discovered electrically-charged particles either repelled or were attracted to each other. But the only way to validate the equations was to assume light travelled through space at a constant speed, regardless of the speed of its source. How odd that must have seemed. 

By way of example, in contrast, a bullet fired from a moving car, to a bystander, will observe its velocity in terms of it's speed added to the car’s speed. Later on physicists Albert Michelson and Edward Morley reached the same conclusion. Thai is, whichever you look, light’s speed is a constant.  

Hence Einstein’s genius made the connection- the speed of light was an absolute - it is invariable and cannot be exceeded. In fact the speed of light is more fundamental than time or space.  The interesting point is in relativity the certainty of the speed of light is inextricably tied to the very fabric of the universe and one would posit it cannot exist outside of this universe. So that Einstein concluded if the speed of light is invariable and absolute, space and time must be flexible and relative to accommodate this phenomenon. 

Einstein’s Special Relativity theory concluded space and time are not independent- so, the laws of physics remain constant in all inertial frames. But the problem remained that Newtonian gravitation didn't quite fit, so that in his General Theory of Relativity, we have the idea of curved space – time and the 3 dimensions that make up the curved 4 dimensional continuum of space-time. 

Hence, matter and energy free from non-gravitational effects, is forced along the shortest path between two points through curved space time geometry. This space time curvature is formed from the distribution of energy and matter.
It is the matter present that results in the curved space time, just as the curvature of space time determines how other large scale matter moves through it.

The laws governing the universe apply to all observers, regardless of the observers reference frame. His general relativity principle was used to predict the existence of stars so massive that they have collapsed in on themselves. Their gravitational attraction is so powerful that nothing – not even light – is thought can escape from it. These  singularities are called black holes.

But Einstein was also deeply disturbed by the fuzziness of quantum mechanics. "Despite having instigated it, Einstein never really believed in quantum theory," says John Barrow from the University of Cambridge.

Einstein spent much of his life searching for a theory. Never comfortable with the outcomes of quantum mechanics, he wanted to create a theory that could combine gravity and the rest of physics, with the quantum element as a secondary consequence.

The solution provided by Einstein to bring the two forces together into a "unified field theory", was to add another tiny dimension so small we couldn't see it.

He couldn’t get that to work, just as we can’t today with additional dimensions, despite entertaining some promising hypotheses. 

The conundrum revisited. 

To reiterate general relativity says that objects' behaviours can be reliably predicted, whilst quantum mechanics contends one can only say there is a probability that they will do something. Philosophically if the latter is true than maybe we have more of a hand in creation than we think and we might talk about GOD’S chance creation, without meaning to be irreverent. But if the former holds true than one might be inclined to think we feel and act as if we are free, but one must always be restrained to the extent the laws of big picture physics. Einstein famously remarked that GOD does not play dice with the universe, so we can deduct that in this respect he believed in determinism. For Einstein, as I have said, was very much aware of the contradiction and spent his life searching for his own quantum solution.

To satisfy himself he constructed his so called cosmological constant dimension to cancel out the ground state infinities which were to curl up into a tiny shape.           

For relativity simply helps us understand such things as curved space – time so that we can calculate the gravitational effect. But this is big picture stuff. As accurate in aggregates as it may be, as in observation and calculation, it is still rather obviously not how everything works in the smaller scale.

The macro level of the universe and cosmological laws.

The laws of the universe are human constructs, under the seeing eye of our earth bound experiences, a product of the universe we experience. For this reason one is prone to echo truths as they pertain to that earthly existence. But of course, as Einstein demonstrated, the laws of the universe apply independently to that of the observer, whatever frame the observer is in. Nevertheless, because that is a reflections of our earthly existence, one can imagine how easy it is for small modifications (hitherto undetected) to radically change those laws. 

Another key cosmological principle, on the same tact, is the notion that the spatial distribution of matter in the universe is homogeneous and isotropic when viewed on a large enough scale. The risk is, having no other universes to which to compare, such axiomatic principles can lead us circuitously to erroneous conclusions. 

To reiterate and summarise my thoughts, Einstein’s general theory of relativity and its gravitational effects is a classical theory that does not incorporate the uncertainty principles which governs all other known forces in the universe. For Big picture physics may not always easily translate well at the ground state surface we populate, so one can say the devil is in the detail. Hence we have been grappling more than 100 years on with this detail, notwithstanding an explosion of ideas and remarkable advancements in engineering and technology, not to mention the marvellous images beamed from Hubble and Voyager. What appears rather obvious though, if we could modify these laws just slightly, a solution could be provided from the current crop of hypothesis that populate the current thinking, such as string theory, quantum loop and M theory etc.

Quantum loop theory for instance might work if it was found that certain light colours did, minutely, travel in excess of the speed of light. But so far no observation has revealed such a phenomena.   
I will examine each of these individually  in more detail later on. 

The Universe in a Nutshell – Quantum Mechanics  
Max Planck’s suggestion in 1900 was that light always comes in small packets called quanta. Heisenberg’s then demonstrated the uncertainty theory.That is a particle times the momentum is larger than Planck’s constant, a quantity almost equal to the energy content of one quantum of light. In the 1920’s Heisenberg, Dirac and finally Schrödinger ideas were synthesised and uniquely espoused in Schrödinger’s hapless cat - wave-particle duality.

However difficulties were encountered in extending quantum ideas to the Maxwell field, comprising waves of different wave lengths, swinging in a pendulum fashion from one value to another. Calculations of the ground state fluctuations assumed infinity, but this is not what the observations revealed. For as energy density is just like matter, so this means that there must be enough gravitational force for the universe to curl up into a single point, which of course hasn’t happened. One could say there is no ground state gravitational effect because it is cancelled out by something like Einstein’s cosmological constant. However what arose as solutions involved symmetrical models and supersymmetry that cancelled out these infinities. These were later abandoned in lieu of the various theories that I will discus later.   

The narrative above is an attempted summary from Stephen Hawking book entitled ‘The Universe in a Nutshell’.  

Hence this new theory of physics as in quantum mechanics superseded both classical physics, and even the Theory of Relativity, although it remains still a classical model in its own right. But amongst physicists and the scientific community Quantum theory or quantum mechanics is the more highly regarded model of the universe, at least unequivocally so at the sub-atomic scales, although for large objects Newtonian and relativistic physics work perfectly well.

Hypotheses analysis. 

String theory
The idea behind string theory is very simple. Electrons for instance are not particles at all. Rather they are tiny loops or "strings", so small, they resemble points.

Just as the strings on a guitar, these strings are under tension, to vibrate at different frequencies, dependant on size, which determines  what sort of "particle" each string is and its attraction to say an electron. Vibrate another way, and you get something else and so on. The strong force binds the nucleus, the weak force does nothing, but if given enough force the nucleus parts: the reason given some atoms are radioactive.

The missing link is there’s no particle to carry the force of gravity. But some physicists think there is, aptly named a “graviton".  They haven’t  mass, always spin in a particular way, and travel at the speed of light.

But we haven’t been able to find one.

Loop quantum gravity
I find this theory more appealing. It proposes space-time is actually divided into small chunks. When you zoom out it appears to be a smooth sheet, but when you zoom in, it is a bunch of dots connected by lines or loops. These small fibres, which are woven together, offer an explanation for gravity.
This idea suffers the same fate as string theory, there's no hard evidence. 
There is very good u tube video you can watch on it under that name.  

Entanglement
This is interesting as it eliminates the need for time.
Quantum physicists Don Page and William Wootters developed this idea in 1983 which posits time as an emergent phenomenon called entanglement. The idea is different quantum particles share existence, (even though of course they are physically separated) so that when describing their respective states one can reference them relative to the other entangled particles. I like the mystical aspect to this idea. 

Hence time is  only an emergent phenomenon, arising from the quantum entanglement. In other words, time is simply an entanglement phenomenon, to synthesize clock readings into the same history. 

Subsequently, the Wheeler–DeWitt equation was formulated that combines general relativity and quantum mechanics – by leaving out time altogether.

The idea was first introduced in the 1960’s but was taken up again in 1983 by Page and Wootters  whose solution (as above) is based on the quantum phenomenon of entanglement.

Page and Wootters have argued that entanglement can be used to measure time. In 2013, at the Institute Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas.

Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicted.

Furthermore it has been reported Physicist Seth Lloyd maintains  that quantum uncertainty gives rise to entanglement, the putative source of the arrow of time. 
Hence one might posit the cause of the measurement of one particle determines the effect of the result of the other particle's measurement, cancelling out to zero.

Many Worlds Interpretation   

This was first put forward by Hugh Everett III back in the late 1950s. The theory is also referred to as MWI, the Relative State Formulation, the Everett Interpretation, Theory of the Universal Wave function, Many-Universes Interpretation, Multiverse Theory, Many-Worlds and M -Theory.  
 

The idea is there does not exist any difference between a particle and system before and after they  have been observed, as they have no separate way of evolving.
 
Rather the observer becomes a quantum system, to interact with other quantum systems. Each time quantum systems interact with each other, so the wave function does not collapse, but actually splits into alternative versions of reality.
This view is predicated on the basis all of the information from wave functions is preserved so that each individual universe is completely deterministic, and the wave function can evolve forwards and backwards. Under this interpretation, quantum mechanics is therefore not the underlying reason for the arrow of time.

Hawking’s brane theory

Hawking’s brane theory is more in line with the original idea of Einstein with only one additional dimension.  He uses the idea of imaginary time and the visual idea of a Hologram to explain his theory.     

Imaginary Time

While looking to connect the quantum field theory with Quantum mechanics, Hawking introduced the concept he called imaginary time. It has a similar relationship to normal physical time as the imaginary number scale does (uses imaginary numbers that do not compute) to the real numbers in his plane. That might best be described as a perpendicular axis to regular time. It provides a way of looking at the time dimension as if they were dimension of space. So it is capable of moving forwards and backwards and so on, analogous as to how that could happen in space.

A feature of this concept is its ability to mathematically smooth out gravitational singularities. Singularities (like those at the centre of black holes) pose a problem for physicists, because they are areas where the known physical laws don’t apply.  When visualized in this imaginary time, however, the singularity is removed and the singularity or Big Bang functions like any other point in space-time.
It’s a very useful theoretical construct.

Conclusion
I prefer the ideas of the entanglement and loop gravity for their simplicity and rationality. My feeling is that time cancels out to zero, or alternatively can be viewed as a relatively minor variable.