We are living but on a spec of dust looking out into the darkness

Jack Dikian

September 2011

The more I think about just how much we have been able to infer about the universe we live in the more amazing it all seems. I mean, here we are living on an unassuming rock orbiting a star near the outskirts of a galaxy. Our galaxy is estimated to contain 200 to 400 billion stars. Current estimates guess that there are 100 to 200 billion galaxies in the Universe. The universe is vast and we are living but on a spec of dust looking out into the darkness, looking back in time, and trying to make sense of it all.

The WMAP Explorer mission that launched June 2001 to make fundamental measurements of cosmology is analogies to a trapdoor spider coming out of its silk-lined burrow to examine the perimeter surrounding its burrow before it goes back inside to think about how might other terrains be like, what kind of soils, how small puddles of water be compared to vast oceans, and so on and so forth.

But, that’s exactly what the WMAP has been able to achieve. It has been able to study the properties of our universe as a whole. WMAP has been stunningly successful too, producing our new Standard Model of Cosmology. The 7-year data provide compelling evidence that the large-scale fluctuations are slightly more intense than the small-scale ones, a subtle prediction of many inflation models.

One of the problems the Big Bang theory was not able to explain is the horizon problem. Distant regions of space in opposite directions of the sky are so far apart that, assuming standard Big Bang expansion, they could never have been in causal contact with each other. This light travel time between them exceeds the age of the universe. Yet the uniformity of the cosmic microwave background temperature tells us that these regions must have been in contact with each other in the past.

The Inflation Theory, developed by Alan Guth, Andrei Linde, Paul Steinhardt, and Andy Albrecht, offer a solution to this and several other open questions in cosmology. Inflation supposes a burst of exponential expansion in the early universe, assuming distant regions of the universe were actually much closer together prior to Inflation than they would have been with only standard Big Bang expansion. Thus, such regions could have been in causal contact prior to Inflation and could have attained a uniform temperature.

Other reading

Alan H. Guth & Paul J.Steinhardt, "The Inflationary Universe", Scientific American, May 1984.

Andrei Linde, "The Self-Reproducing Inflationary Universe", Scientific American, November 1994.

Scott Watson, "An Exposition on Inflationary Cosmology", WWWarticle, 2000.

Alan H. Guth, "The Inflationary Universe : The Quest for a New Theory of Cosmic Origins", 1998.

First Light, God's handiwork in Creation and the Big Bang

Jack Dikian

July 2011

Ever since I was a young boy I’ve been fascinated by the biblical statement "Let there be light" (Genesis 1:3). I still remember the curiosity and what must have been a child's wide eye - learning the scripture at school and church.

Much later I became interested in cosmology theory, Big Bangs, string landscapes and all the time holding on to my earlier notions of a first dawn, a first light.

Much has been written (speculated rather) about how the universe might have unfolded a few seconds after the big bang. Consider the Planck epoch (up to 10–43 seconds after the Big Bang) dealing with an unimaginably small period of time after the big bang where, perhaps, forces as we know them today might have been indistinguishable (viz a viz unification). Or consider the Inflationary epoch, a period between 10–36 seconds and 10–32 seconds after the Big Bang where it’s thought the universe went through rapid expansion and provided for the early seeds of structure to be laid down.

It isn’t until the Photon epoch however (between 10 seconds and 380,000 years after the Big Bang) when neutral atoms begin to form and the universe begins to became transparent to visible light.

First Light

So the early universe was dense, hot, and shared little resemblance to what we have today. Photons would be reflected and scattered randomly in a largely "opaque" universe. As the universe continues to cool over the first 380,000 years or so, electrons and nuclei began to form atoms and photons are no longer strongly interacting with stable atoms. At this point photons begin to travel through the universe more freely as the universe became transparent to light, and so there is light.

Interestingly, these photons are still traveling today and can be detected as the "cosmic microwave background radiation”. Almost 1% of the static we notice on our television screens when we are switching between channels (all those in-between channels) is remarkably the noise of the early universe - the after glow.

Einstein's Biggest Blunder

Jack Dikian

May 2011

A team of planetary scientists using the Anglo-Australian Telescope contributed to the mapping of galaxies over a volume of the Universe and has shown that dark energy responsible for expanding the universe is real and not a mistake by Einstein viz a viz the cosmological constant.

When George Gamow was discussing cosmological problems with Einstein, he (Einstein) had remarked that the introduction of the cosmological term was the biggest blunder of his life.

Einstein introduced his cosmological constant it into his general theory of relativity almost as a last resort wanting to force his theory to yield a static universe as he had thought the universe to be.

We know now the universe is not static and is expanding at an accelerating rate, just as his original field equations were predicting. Einstein was never comfortable with the [constant] and a clue is in his 1917 paper which ends with

“It is to be emphasized, however, that a positive curvature of space is given by our results, even if the supplementary term [cosmological constant] is not introduced. That term is necessary only for the purpose of making possible a quasi-static distribution of matter, as required by the fact of the small velocities of the stars”.

The survey of 200,000 galaxies by an international team, led by Chris Blake of Swinburne University, took four years to complete, aimed to measure the properties of "dark energy" — the concept of which was revived in the late 1990s when astronomers began to realize the universe was expanding at an accelerating rate.

The acceleration was a shocking discovery, indicating the universe is filled with a new kind of energy that is causing it to expand at an increasing speed.

Black Holes Older Than The Universe

Jack Dikian

May 2011

According to the work by Professor Bernard Carr from Queen Mary University in London and Professor Alan Coley from Canada's Dalhousie University published on the pre-press website arXiv.org, some black holes may be primordial. That is some black holes bounce between a contracting and expanding universes.

Coley and Carr speculate that primordial black holes could survive as separate entities and from a previous epoch (assuming of course that a bounce occurs at all and survives singularities).

According to general relativity, the initial state of the universe, at the beginning of the Big Bang, was a singularity - a point in space-time at which the space-time curvature becomes infinite and much of the physics we know breaks down.

Even with the success of quantum mechanics we don't have a good theory of quantum gravity.

Still, such a speculation, as well as pushing the boundaries of our current theories, bounces in the universe may also allow for differences in the fundamental constants of nature such as (say) the speed of light.

I Am Convinced God Does Not Play Dice

Jack Dikian

March 2011

Introduction

The Copenhagen interpretation of quantum mechanics proposes, generally, that the outcome of any measurement cannot be measured with certainty. This leads to the situation where measurements of a property performed on two identical systems can give different answers.

However, can a deeper reality, hidden beneath quantum mechanics, described by a more fundamental theory predict the outcome of measurement with certainty. Einstein, a proponent of a deeper reality (hidden variables) hidden famously insisted that, "I am convinced God does not play dice”.

Quantum mechanics puzzle

Quantum mechanics creates the puzzling situation in which a measurement of one system can "poison" the measurement of the other system, no matter what the distance between them. One could imagine the two measurements were so far apart in space that special relativity would prohibit any influence of one measurement over the other.

For example, say, in a neutral-Pion decay, where two photons travel some light years apart – if the spin of one photon is measured, quantum mechanic suggests that that measurement instantaneously forces the second photon into a state of well-defined spin - even though it is light years away from the first.

Einstein, Podolsky, and Rosen (EPR) argued that elements of reality must be added to quantum mechanics and postulated that the existence of unknown properties should account for the discrepancy – that there is a deeper reality.

A conundrum

How do we reconcile the fact that the second photon "knows" that the spin of the first photo has been measured, even though they are separated by light years of space and far too little time has passed for information to have traveled to it according to special relativity?

We can accept the postulates of quantum mechanics its seemingly uncomfortable coexistence with special relativity, or we may believe that quantum mechanics is not complete:

Are we smart enough

Jack Dikian

February 2011

Last night I was invited to dinner at my close friends and neighbors – towards the end of the night we got onto a conversation topic that’s always near to my heart; the lofty subject concerning the universe. Its size, structure, complexity, age, origin and not least what seems like the insignificance of our lives in the vastness of even the known universe.

Not only is the universe vast, there are billions and billions of stars and planets with the almost infinite of mysteries that may lie within each star system waiting to be uncovered. Our knowledge, of course, is still in its primordial stages. In an infinite universe, there are infinite possibilities and the idea of god might not be so unlikely.

We may be seeing the universe as it is because otherwise we wouldn't be here to see it, we wouldn't exist. Some claim there are many universes and because their sub-atomic particles are slightly different than ours they do not support life.

Some theories propose that the universe is best explained in 11 dimensions, and there could be another entire universe less than a millimeter away from us….and us being oblivious to it. But it may be more than that, it’s entirely possible that we, living in the restricted dimensions of space and time are beyond understanding the workings of the universe.

In the same way fish may be barely be aware of the medium in which they live and swim, so the microstructure of empty space could be far too complex for our unaided human brains." It's as if a fish is swimming in one pond, completely unaware that thousands of other ponds exist mere meters away from it.

Understanding that those ponds even exist, let alone understanding their connection to the original pond, is understandably beyond the comprehension of a single fish.

We similarly, attempt to make meaning and develop constructs such a unifying theory to describe how the universe works, idea of multiple parallel universes, human consciousness and the very idea of reality – we as fish may well find that the universe be simply beyond our understanding.

A second universe

Jack Dikian

January 2011

Paul Adrien Maurice Dirac (whilst not a household name) is considered by many to be the greatest British theorist since Sir Isaac Newton. All the great minds that pioneered atomic physics were left trailing by Dirac. When Einstein read a paper by the young Dirac, he said, I have trouble with Dirac – "this balancing on the dizzying path between genius and madness is awful..".

In 1925, for reasons only known to himself, he set out to unite the two most difficult and counter-initiative ideas in history – Quantum Mechanics and Special Relativity (where as a fall out, objects behave differently as they travel at speeds approaching the speed of light). It must be remembered that by the late 1920’s quantum mechanics was consistently producing erroneous results for calculations describing electrons as they traveled at high speed.

As well as this, Dirac had an additional aim. Dirac had a much more esoteric motivation. He was once quoted of saying “a physical theory must have mathematical beauty”. For him, the fact that quantum mechanics and relativity weren’t reconciled was more that just an inconvenience – it was ugly.

Around 1925 he put his extra ordinary mind on the problem of bringing together the two new ideas of twentieth century physics. It is said that he worked on this problem alone for some three years before in 1928 he honed in on one mathematical formulation – an entirely new description of what goes on within the atom. Dirac knew it was right partly because it had mathematical beauty (see equation above).

As far as human achievements go it up there with Shakespeare's greatest works (something which by the way a very dear friend constantly reminds me of) and the Origin of the Species. Dirac’s equation describes how reality works at the fundamental level.

But, incredibly when Dirac looked at his own equation he noticed something that can only be said to be shocking. He later said, his equation [knew] more than he did.

In essence his equation was telling him that there is another universe that we had never noticed before. That’s because instead of his equation having one answer, it has two. The first describes the universe we know…the second describes a kind of mirror image to our universe made of atoms whose properties are reversed. As well as matter, Dirac’s equation predicts the existence of antimatter.

Dirac seems to be saying that for every piece of matter in our known universe, there can exist a corresponding piece of antimatter. Just like a world in a mirror a universe made of antimatter would look and work just like ours.