The story begins with the seemingly temporal question of what we mean by a meter or a kilogram. The French Revolution facilitated the first moves towards an egalitarian standard of weights and measurements; a bar of platinum was housed in the archives of the French Republic against which a meter could be measured. As the bar was handled, it began to shrink over time so scientists were soon on the look-out for a better method. Then there is this interesting mention of the Lockheed-Martin that controlled the day-to-day operations of a Mars mission in 1998. While it was sending data in Imperial units (miles, feet, pounds), NASA was assuming them in metric (meter, kilogram etc) and the result - $125 million space craft became part of Martian dust as the mis-calculation did not eject the space craft in the right time (The spacecraft was 60 miles above the Surface - 60 KM is a different entirety)
The introductory chapter stressed on the need to have good constants for understanding the Universe, like the velocity of light, gravitational constant etc.The numerical value of the weight of an electron will vary according to the units used. If instead you ask how much heavier is a proton when compared to the weight of an electron, you get a number that is independent of units. This number, approximately 1836, is an example of one of the "constants of nature". The value is Universal and is quite similar to what we use as 'equivalence' in Chemistry and amu in Nuclear Chemistry.
A small change in the relative weights of the electron and proton would result in atoms flying apart (Read: one of the fundamental forces of nature). There would be no possibility of gluing these fundamental particles together to make atoms and ultimately life (Haven't we discovered more precisely recently). The "Superhuman standards" discusses well the constants 'c' and 'h', with a few anecdotes from Einstein and Planck. Both of these are highly essential in present day science. The need for Quantum Region is well discussed by an illustration with some light on Heisenberg's Uncertainty 'throw'. The book is filled with some very good quotes and here is one I liked:
Here lies John Bun,
Who was killed by a gun,
His name was not Bun, but Wood,
But Wood would not rhyme with gun,
but Bun would.
And this infinite calculation of the number of protons in the Universe by Arthur Eddington was baffling:
"I believe that there are 15,747,724,136,275,002,577,605,653,961,181,555,468,044,717,914,527,116,709,366,231,425,076,185,631,031,296 protons in the universe and the same number of electrons."
This might be not a correct number because we do not know the geometry of the Universe, but if it was derived from some other constant, may be he was true.
In the last part of the book, there is certain amount of mathematics that did not go well with me, but I felt that a lot of hard work has gone into the collection of some beautiful information. The Eddington's Unfinished symphony, The Mystery of Very large numbers, Biology and stars, The Anthropic Principal, Altering Constants and re-writing History, New Dimensions and Variations on a
Constant Theme are a few chapters that carry good reference and sketches along with some useful quotes.
With description of lots of constants around the science of Physics, the author seems to throw lot of light on the construction of Universe and suggests us to observe the same and verify what happens or what would happens if constants change! The change may at be any distant digit from decimals. With the anthropic principle at the helm of the discussion, we need to listen to what these values signify.
The book fluctuates between moments that are profoundly life-affirming and others that are deeply depressing, with sentences such as: "If the constants of nature are slowly changing then we are on a one-way slide to extinction."
This isn't just extinction because the Sun will eventually swallow us up: we still have some hope of avoiding this minor event in the history of the universe by making it to another star-system. We are aware, for example, that without the Earth's natural magnetic field, our atmosphere would be stripped
away by solar winds? Such is the fate of Mars, which has no magnetic field and which is why it appears 'red'.
The dimensionless constant appears to show some sanctity. Time variation of fundamental constants is subjected to theoretical and experimental research by a number of physicists such as; Arthur Eddington, Paul Dirac, George Gamow, Robert Dicke, Brendan Carter, Paul Ehrenfrest and others. The fine-structure constant was originally introduced in 1916 by Arnold Sommerfeld, as a measure
of the relativistic deviations in atomic spectral lines of the Bohr's atomic model. This constant is interpreted as a measure of electromagnetic force that holds the atoms together or the strength of the interaction between electrons and photons; the ratio of two energies, the energy needed to bring two
electrons from infinity to a distance against their electrostatic repulsion, and the energy of a single photon. It is also defined as the ratio of the strengths of the electromagnetic and gravitational interactions. This constant is a dimensionless quantity (1/137.035999679); hence its numerical value is independent of the system of units used. It is increasingly becoming apparent to a few physicists that some fundamental constants such as the speed of light (c), fine-structure constant, proton-
electron mass ratio, and gravity (G) have changed over the last 13.7 billion light years.
What is not understandable by the humans is the 'fashion' of the Universe provided there are numbers attached to it. The author delivers his last paragraph with a prediction that one day the numbers would prove to be some 'PIN' numbers or bar-codes that should help unlock the Secrets of the Universe. The last part of the book has abstracts which carry the gist of the all preceding chapters. You can recollect what you have read or forgotten through these pages. A baffling amount of reference has gone into the writing of this book, so that it is prudent to go after the book with a valid reason.
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