Wednesday, June 7, 2017

The  Unknown  Universe

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The Unknown Universe by Stuart Clark ; Published by Head Zeus ; Pages 303 ; Price U.K.Pound 16/99.
The author of this book Stuart Clark is a fellow of the Royal Astronomical Society who  celebrates and challenges the current state of modern astrophysics with a wide-ranging and accessible look at the field’s most cutting edge research. This is a fascinating voyage of discovery for the layman and scientist alike. Stuart explores the arguments, the rivalries, and the triumphs of astrophysics with lively writing and an enviable knack for converting the most complex topics into clear, easy-to-absorb ideas. 

The European Space Agency published a groundbreaking  image three years ago of the Universe as it was 13.7 billion years ago. This was welcomed by astronomers. Then doubts arose. The map of cosmic microwave background radiation left over from the Big Bang shows a universe that consists of nothing but a “gigantic cloud of atoms.” Observations on the rotation of galaxies and the speed of the Universe’s expansion  led scientists to theorise  the existence of dark matter that can’t be seen and dark energy that can’t be found, and raised fundamental questions of  the current understanding of gravity itself. Stuart explains all these to the layman both clearly and crisply.

The map released by the European Space Agency of the afterglow of the Big Bang took us  into  440 sextillion kilometres of space and 13.8 billion years of time. This was at once the acme of science as also the demolisher of almost everything we hold cosmologically sacrosanct.

The  book under review  is the first one to address an epoch-defining scientific paradigm shift. It also raises a whole host of questions. Do we have to rewrite   Newton's famous laws of gravity ; Are  dark matter and dark energy  just celestial phantoms? Can we ever know what happened before the Big Bang? What’s at the bottom of a black hole? Are there Universes beyond our own? Does time exist? Are the once immutable laws of physics changing?

This is the best popular science book you can lay hands upon. Stuart Clark  knows how to talk about the holes that are in science but doesn't tear apart the science that allows us to see the holes in the first place.

Black holes mean that there are holes in the universe and also that there are holes in our understanding of the universe. Observers of the universe want to know the why (the theory), and they also want to know the how (the model). Eddington and Kepler both built models. Newton and Einstein built a theory. Time to Newton is absolute and  to Einstein it is an illusion (relative). There is nothing more exciting than the Planck map of the universe, and this book will teach you something you did not  know.

The author presents  a fine history of cosmology, and  makes it clear that our knowledge and ignorance seem to be expanding co-terminously. The Planck  data showed  “cosmology is not finished.’ ”

 Clark begins his history in the 17th century with Kepler, Halley, and Newton, ending in the unsettling 21st, where the Universe explained so brilliantly by Einstein, has revealed features that he didn’t explain. Educated readers know that the term “unknown” as applied to the universe is literally true because 95 percent is invisible, detectable only because its energy and gravity influence movements of the 5 percent we see as stars and galaxies.

 There are many  cosmic mysteries that Clark explains for the layman.  We get a glimpse of the genius of Newton as well as examples of the irrational views commonplace during his time. The history and evolution of theories about the Solar System are touched upon. The only equation that manages to appear in the book is Einstein’s E = mc2.

A lot of ideas including Arthur Eddington’s bold conjecture that stars are nuclear reactors that use nuclear fusion to generate their energy are outlined. Most of us credit Edwin Hubble with the discovery of the expansion of the Universe. But Clark  writes:

“In 1929, Hubble published results that ignited science in the way Lemaitre’s paper of two years earlier should have done. Hubble showed that the further a galaxy was, the greater was its redshift. It was definitive proof that the Universe was expanding, exactly as Lemaitre had predicted, yet Hubble did not include a single reference to him or his work.”

We live in astounding times. The bulk of the exoplanet discoveries are being made in the data gathered by and downloaded from the Kepler Space Telescope. The story of the discovery of Eris and how that led to the demotion of Pluto’s status is outlined.

The book provides some details of the famous rivalry between Harlow Shapley and Edwin Hubble in the early decades of the 20th century in which Hubble ultimately prevailed. Even though Hubble won that rivalry with Shapley, it’s Shapley’s chosen naming of ‘galaxy’ that is commonplace today rather than the phrase Hubble favoured ‘extragalactic nebulae.’

  Quantum mechanics with its uncertainties and probabilities hard-wired into the Universe became accepted even though titans like Einstein didn’t like God playing dice with the Universe.

Some  Interesting Titbits-

1.Planck Photo—The Planck photo was taken by a ESA Spacecraft stationed at 1.5 million kilometers away from Earth called Planck after the great German physicist, Max Planck The probe had spent two and a half years painstakingly building up the picture, pixel by pixel.
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 Max  Planck                  Planck Spacecraft

2.Edmond Halley—after whom the Halley’s Comet is named never lived to see the return of the Comet—after 75 years-- as predicted by him. On 14,January 1742, after a 22 year stint as the second Astronomer Royale, the eighty-five years old Halley asked for a glass of red wine. He drank it, placed the glass on the table next to his chair and expired peacefully.

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         Halley and his Comet

3.Albert Einstein---All of you have seen this unique photo of Einstein—“ Wild hair, bushy moustache, careworn lines around deep dark eyes, tongue sticking out !.The famous tongue photo was taken on his 72nd birthday in 1953 .A copy signed by Einstein was auctioned in 2009 for $ 74,324/- making it the most expensive photo of the scientist ever sold.

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Albert   Einstein  

04 / 06 / 2017

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