After The First Three Minutes

Title: After The First Three Minutes - The Story of Our Universe

Editor: Thanu Padmanabhan

Publisher: Cambridge University Press 1998 (First)

ISBN: 0-521-62039-2

Pages: 210

T Padmanabhan is a Professor at the Inter-University Centre for Astronomy and Astrophysics, Pune, India and is a noted Indian scholar on cosmology and astrophysics. He has authored several titles for graduates in Physics. This book narrates the story of the universe from its birth at the Big Bang upto the present moment. Curiously, no attempt at making glimpses on the predicted future of the universe is taken. The author indicates in the foreward that the book is intended for the serious reader, who ‘really wants to learn’. True to the claim, it displays extensive coverage of the basics in the first few chapters which make any peer envious. The narrative starts from the melting of common ice and reaches high-energy nuclear disintegrations in a mesmerizingly connected way.

The second chapter is a particularly illuminating tutorial on fundamentals. Every necessary concept is thoroughly explained and illustrated with the help of line sketches. If we heat a solid substance, it melts because the molecular bonds in the crystal lattice are destroyed due to the energy input. If we continue heating, the molecular connections in the liquid breaks down and it turns to gaseous state. The molecules are almost free in this state and on further heating, the weak connections between molecules fail and it is split into constituent atoms. Further ingress of energy will remove the electrons from atoms and it reaches the plasma state. After the electrons are removed, the nucleus becomes ionized and further energy input will break the nucleus into protons and neutrons. Still higher energy breaks the nucleons into component quarks which are the most basic material which is not divisible further (as of now!).

The third chapter is an excellent primer on the observational technologies by which astronomers painstakingly watch the sky. Visible light constitutes only a small window of the electromagnetic spectrum. Celestial objects emits radiation on a wide range of the spectrum and human beings are handicapped by the peculiarity of their naked eye not to see outside the visible range. Visible light and infrared rays reach the surface of earth and ground-based instruments can be used to study them. Ultraviolet, radio, X-ray and gamma rays are mostly absorbed by the atmosphere and ozone layers making it impossible for scientists to view the sky from ground. Blocking of such harmful radiation, however, is absolutely essential for the survival of life forms. Observation of the universe on these parts of the spectra is possible only by high-altitude baloons, rockets or satellites.

After setting the ground work, the author moves on to star-formation techniques in the fourth chapter. Rotating gas clouds which fall under self-gravity sets in nuclear reactions fusing hydrogen to helium and a star is formed. Upon glowing for several million years, the hydrogen is exhausted and heavier elements are created as part of the final reactions. Depending on the size of the star at this stage, it ends up as a white dwarf or blackhole. Just before the final step in the process, the outer ring of the star explodes in a supernova, spewing the stellar material rich in higher elements like carbon and nitrogen into the interstellar space. Stars form larger structures called galaxies. Our solar system is a part of the Milky Way galaxy. Several such galaxies form groups of galaxies. Our own Milky Way, along with another nearby galaxy Andromeda and several such galaxies constitute what the astronomers call the ‘Local group’. Millions of such clusters make the universe.

The universe is expanding right from the Big Bang and it had an inflationary phase just after the Bang. All theories break down at the mathematical singularity of the Bang. Inflation is an essential postulate to explain the formation of structures like galaxies and clusters, otherwise the smoothness of the universe would make it impossible for the formation of structures. For studying the universe under the influence of strong gravitation, Einstein’s General Theory of Relativity is essential, but just after the universe was born, its size would’ve been so small that a quantum cosmological model is required. However, relativity and quantum mechanics are strange bed fellows and unifying these two wonderful theories of the 20^th century would make a ‘quantum’ leap in human knowledge!

For galaxies to form, it is absolutely required to have small fluctuations in the density of matter. Matter comes in two forms, normal visible one and dark matter which are undetected as yet. The proof of this density contrast (fluctuation) was observed by the cosmic background explorer satellite (COBE) in 1992. It categorically verified that small variations in the microwave background radiation exist. The author explains quasars and galaxy formation in the form of spirals and ellipticals.

The book is superb as the fundamentals are covered in so much detail and are easily digestible. Several illustrations of key concepts are sprinkled along with the text, keeping the points self-explanatory. A modest but appreciable glossary of key concepts are also given at the end.

However, even with so much advantageous points, the book is not suitable for the general reader. It lacks the human touch and the description often degenerates to mechanical style, particularly in the latter chapters. The ‘degeneracy pressure’ (an unrelated quantum mechanical term!) of the second half of the book is considerable, as to turn most readers away. There is no flow of the argument along the length of the book and each chapter is a stagnant pool of ideas which may be taken out of context, without losing the inherent merit. It looks as if the book was written by several authors because of the independence of the chapters, but this is clearly not the case! The author declares that the book is written with the serious reader and has avoided telling stories like ‘as Prof. Great was driving with his wife to the concert, it suddenly occurred to him…’. This is a clear dig on other popular science authors, but the stubbornness of the author in omitting such simple but easily palatable anecdotes took the life out of the work. This book may be useful for a higher student in preparing the ground work for further studies in the field, but not to the layman. Also some diagrams given are needlessly complicated thus counterbalancing the effects of others. Most importantly, the author is unable to justify the title! No description of any sort is given as to what happened immediately after the first three minutes from Big Bang. The title seems more to be a publisher’s trick to attract general attention.

The book is not recommended for the general reader.

Rating: 2 Star