Nature’s laws may vary across the universe – and so what if they should

There were headlines last week because according to a new paper published  in Physical Review Letters it may be that one of the “laws of nature” may vary across the Universe. Observations from two large telescopes pointed in different directions of the universe seem to show that the electromagnetic force which is measured by the fine structure constant, α,  may be different in different parts of the universe.

Indications of a spatial variation of the fine structure constant, by J. K. Webb, J. A. King, M. T. Murphy, V. V. Flambaum, R. F. Carswell and M. B. Bainbridge, Phys. Rev. Lett., 107, 191101, 2011, http://arxiv.org/abs/1008.3907 

Since the “laws of nature” and the “laws of physics” are merely expressions of observed regularities in our observable time and space they are – of necessity – empirical conclusions. Since we – as yet – have no idea “why” the “laws” we observe should be as they are and why the “fundamental constants” take the values they do, it seems to me unremarkable that there should be areas of time or space (not observed as yet) where these “laws” – as we have formulated them – do not hold exactly. There may well be errors of observation of course but observations made correctly must trump theories and models – no matter how simple or beautiful they might be.

Even assuming the expansion of the universe has been correctly observed, we have no idea why it should be happening. We are nowhere near explaining why galaxies may be hurtling away from each other but the particles making up the galaxies are not themselves moving away from each other.  The galactic dance follows “laws” yet to be discovered. And of course there are all the theories of alternate universes, each following its own “laws”.

Why the “laws” of physics and nature seem to be so finely-tuned for the existence of life on earth is not so surprising. It is merely because the life that has evolved is that which fits – and can only fit – the prevailing “laws”. What would be surprising and  “unnatural” would be if the fit was not exact and we had life which did not comply with the prevailing “laws”. And so for any part of any universe and with the prevailing “laws”, the life that evolves – if it can evolve – will comply with those “laws”. And if in any particular place the “laws” vary with time, then life will have to evolve to match the change or become extinct.

It gives me great comfort that there are so many things we don’t know that we don’t know. Otherwise we would be able to forecast the future with deadening accuracy.

PhysOrg 

One of the most cherished principles in science – the constancy of physics – may not be true, according to research carried out at the University of New South Wales (UNSW), Swinburne University of Technology and the University of Cambridge.

The study found that one of the four known fundamental forces,  – measured by the so-called fine-structure constant and denoted by the symbol ‘alpha’ – seems to vary across the Universe.

The first hints that alpha might not be constant came a decade ago when Professor John Webb, Professor Victor Flambaum, and other colleagues at UNSW and elsewhere, analysed observations from the Keck Observatory, in Hawaii. Those observations were restricted to one broad area in the sky. 

However, now Webb and colleagues (PhD graduate Dr Julian King, PhD student Matthew Bainbridge and Professor Victor Flambaum at UNSW; Dr Michael Murphy at Swinburne University of Technology, and Professor Bob Carswell from Cambridge University) have doubled the number of observations and measured the value of alpha in about 300 distant galaxies, all at huge distances from Earth, and over a much wider area of the sky. The new observations were obtained using the European Southern Observatory’s ‘Very Large Telescope’ in Chile. 

“The results astonished us,” said Professor Webb. “In one direction – from our location in the Universe – alpha gets gradually weaker, yet in the opposite direction it gets gradually stronger.”

“The discovery, if confirmed, has profound implications for our understanding of space and time and violates one of the fundamental principles underlying Einstein’s General Relativity theory,” Dr King added. “Such violations are actually expected in some more modern ‘Theories of Everything’ that try to unify all the known fundamental forces,” said Professor Flambaum. “The smooth continuous change in alpha may also imply the Universe is much larger than our observable part of it, possibly infinite.”

As John Webb wrote in 2003,

The development of a scientific theory has always followed the need to understand an observation for which no satisfactory explanation previously existed. When developing new theories, physicists tend to assume that fundamental quantities such as the strength of gravity, the speed of light in a vacuum or the charge on the electron are all constant. And when these theories are found to predict the results of new observations, our belief that these quantities are actually fundamental constants becomes even stronger. 

But it is vital to remember the limitations that have been involved in testing these assumptions. Many of the experiments we carry out to test theories are restricted to the here and now – to Earth-bound research labs or to the small part of the universe that we can observe with telescopes. If we could somehow do our experiments in a different place or at a different time, we might well find that the results are different. Indeed, that is what appears to happen when we measure something called the fine-structure constant in the very distant past.

 

 

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One Response to “Nature’s laws may vary across the universe – and so what if they should”

  1. martenvandijk Says:

    The results do not astonish me on account of the intrinsic uncertainty of gravitation, not as consequence of a curvature of space-time by the division of mass and energy in it, but as consequence of a continuous relation between mass and time. Also on account of gravitation changing the speed of light.
    (ref.: http://www.cosmicsignals.wordpress.com)

    The alpha team has been informed.

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