A new paper describes the discovery of the largest known Large Quasar Group – with a longest dimension of some 1200 Megaparsecs and a typical dimension of about 500 Mpc. (One parsec is about 3.3 light years). This LQG is thus some 1600 times longer than the distance between the Milky Way Galaxy and the Andromeda Galaxy. The research team – led by Dr Roger Clowes from UCLan’s Jeremiah Horrocks Institute – has identified the LQG which is so significant in size that it also challenges the Cosmological Principle. As Dr. Clowes remarks:
“While it is difficult to fathom the scale of this LQG, we can say quite definitely it is the largest structure ever seen in the entire universe. This is hugely exciting – not least because it runs counter to our current understanding of the scale of the universe.
“Even travelling at the speed of light, it would take 4 billion years to cross. This is significant not just because of its size but also because it challenges the Cosmological Principle, which has been widely accepted since Einstein. Our team has been looking at similar cases which add further weight to this challenge and we will be continuing to investigate these fascinating phenomena.”
And if the Cosmological Principle does not hold it means that the fundamental constants of the known Universe may no longer be so fundamental or so constant. The list of such constants is long but the most fundamental of these on which we build our understanding of the Universe – which we take as being immutable – are the speed of light in a vacuum, the gravitational constant and the Planck constant. This opens up the possibility that the physical constants may take different values in different parts of the Universe. They may be a function of space and time. They may change over cosmological time – and of course this could mean that the passage of time itself is not uniform. So perhaps the “arrow of time” is really a “boomerang of time”? Or it could be that what starts out as an arrow may be morphing into a boomerang or something else as time progresses (or not). The concept of time – and not only the passage of time – may vary. What if the trajectory of time could loop on itself? or proceed in the form of a double spiral? Even if the Universe is still a non-static Universe – that itself makes a static Universe – Stasis – possible. The possibilities are legion – and not only for science fiction.
Stardate would no longer be uniform – but this could explain the variation between the different series of Star Trek!
Quasar – artists impression NASA-AFP
A structure in the early universe at z ~ 1.3 that exceeds the homogeneity scale of the R-W concordance cosmology by, Roger G. Clowes, Kathryn A. Harris, Srinivasan Raghunathan, Luis E. Campusano, Ilona K. Soechting, Matthew J. Graham, Monthly Notices of the Royal Astronomical Society, http://arxiv.org/abs/1211.6256
Tags: Cosmological Principle, Large Quasr Group, LQG, Observable universe, Roger Clowes, Star Trek, Stardate, University of Central Lancashire
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