The author is a popular writer of physics and her contribution in particle physics and her academic position at Harvard has brought her into contact with well known figures in public life including President Bill Clinton, many artists, television personalities, celebrities, and thinkers of our time.
In this book, the author describes the progress in our understanding of the laws of physics from Galileo to Ed Witten. In her previous book, "Warped Passages," the author observes that in many popular science books, often the authors do not give details about how a theory or a postulate is subjected to experimental verification and how they analyze the results of these experiments to confirm the theoretical predications. She lamented that often the books talk about the scientist who made the discovery and how great they were, but rarely talk about the scientific process. In this book she discusses the process of experiments and analyzing the results. She explores how to tackle the scientific problems, and examines the beauty and truth in scientific thinking, the nature of symmetry, classical and quantum realities, and religion. She also reviews the state of the art equipment, the super particle smasher, the Large Hadron Collider (LHC) about its functions and what it offers to the knowledge of physicists. The author summarizes the ATLAS and CMS detectors of LHC instrument, and the results the physicists are interested which includes detection of Higgs Bosons known as the God's particle. She predicts what the data from Planck and Herschel satellites and LHC may provide about the fundamental particles and what we can infer from them about the laws of nature and the structure of the universe. The author is known to quote from popular and rock music in her books. Here she uses part of Bob Dylan' song as the title for this book. How appropriate is this title for a book about understanding the universe when a guy is being shot and facing imminent death.
"Mama, put my guns in the ground
I can't shoot them anymore.
That long black cloud is comin' down
I feel like I'm knockin' on heaven's door." Bob Dylan
How realistic is the author; about being so close to the heaven's door, in terms of understanding the laws of physics, when we still have not understood the essence of existence and physical reality? We can hold that thought on heaven, come down to earth and sort out the results from LHC experiments first. There is still not a great deal of hope for Higgs Boson and KK gravitons needed for the Randall-Sundrum model for explaining the weak gravity in our universe. Even though the Standard Model (SM) of electroweak interactions perfectly describes almost all existing experimental data, but the model suffers from certain theoretical drawbacks. The hierarchy problem is probably the most fundamental of these: namely, quantum loop corrections in the SM destabilize the weak energy scale O (1 TeV), if the theory is assumed to remain valid to a much higher scale such as the Planck mass scale O (1019 GeV). Therefore, it is believed that the SM is only an effective theory embedded in some more fundamental high-scale theory that presumably could contain gravitational interactions. Models that involve extra spatial dimensions could provide a solution to the hierarchy problem in which gravity plays the major role. The Randall and Sundrum (RS) model proposes a 5D universe with two 4D surfaces ("3-branes"). All the SM particles and forces with the exception of gravity are assumed to be confined to one of those 3-branes called the visible or TeV brane. However, gravity lives not only on the visible brane, but also on the second brane (the "hidden brane") and in the bulk. All mass scales in the 5D theory are of order of the Planck mass. By placing the SM fields on the visible brane, all the order Planck mass terms are rescaled by an exponential suppression factor (the "warp factor"), which reduces them down to the weak scale O(1 TeV) on the visible brane without any serious fine tuning.
At the end of the book the author expresses optimism that her model to describe gravity has a chance of being proved right: This is perhaps a wishful thought. I wished the author, a brilliant physicist, had expressed reasons for such optimisms in her peer reviewed articles to academic journals.
In this book, the author describes the progress in our understanding of the laws of physics from Galileo to Ed Witten. In her previous book, "Warped Passages," the author observes that in many popular science books, often the authors do not give details about how a theory or a postulate is subjected to experimental verification and how they analyze the results of these experiments to confirm the theoretical predications. She lamented that often the books talk about the scientist who made the discovery and how great they were, but rarely talk about the scientific process. In this book she discusses the process of experiments and analyzing the results. She explores how to tackle the scientific problems, and examines the beauty and truth in scientific thinking, the nature of symmetry, classical and quantum realities, and religion. She also reviews the state of the art equipment, the super particle smasher, the Large Hadron Collider (LHC) about its functions and what it offers to the knowledge of physicists. The author summarizes the ATLAS and CMS detectors of LHC instrument, and the results the physicists are interested which includes detection of Higgs Bosons known as the God's particle. She predicts what the data from Planck and Herschel satellites and LHC may provide about the fundamental particles and what we can infer from them about the laws of nature and the structure of the universe. The author is known to quote from popular and rock music in her books. Here she uses part of Bob Dylan' song as the title for this book. How appropriate is this title for a book about understanding the universe when a guy is being shot and facing imminent death.
"Mama, put my guns in the ground
I can't shoot them anymore.
That long black cloud is comin' down
I feel like I'm knockin' on heaven's door." Bob Dylan
How realistic is the author; about being so close to the heaven's door, in terms of understanding the laws of physics, when we still have not understood the essence of existence and physical reality? We can hold that thought on heaven, come down to earth and sort out the results from LHC experiments first. There is still not a great deal of hope for Higgs Boson and KK gravitons needed for the Randall-Sundrum model for explaining the weak gravity in our universe. Even though the Standard Model (SM) of electroweak interactions perfectly describes almost all existing experimental data, but the model suffers from certain theoretical drawbacks. The hierarchy problem is probably the most fundamental of these: namely, quantum loop corrections in the SM destabilize the weak energy scale O (1 TeV), if the theory is assumed to remain valid to a much higher scale such as the Planck mass scale O (1019 GeV). Therefore, it is believed that the SM is only an effective theory embedded in some more fundamental high-scale theory that presumably could contain gravitational interactions. Models that involve extra spatial dimensions could provide a solution to the hierarchy problem in which gravity plays the major role. The Randall and Sundrum (RS) model proposes a 5D universe with two 4D surfaces ("3-branes"). All the SM particles and forces with the exception of gravity are assumed to be confined to one of those 3-branes called the visible or TeV brane. However, gravity lives not only on the visible brane, but also on the second brane (the "hidden brane") and in the bulk. All mass scales in the 5D theory are of order of the Planck mass. By placing the SM fields on the visible brane, all the order Planck mass terms are rescaled by an exponential suppression factor (the "warp factor"), which reduces them down to the weak scale O(1 TeV) on the visible brane without any serious fine tuning.
At the end of the book the author expresses optimism that her model to describe gravity has a chance of being proved right: This is perhaps a wishful thought. I wished the author, a brilliant physicist, had expressed reasons for such optimisms in her peer reviewed articles to academic journals.
Reference: Knocking on Heaven's Door: How Physics and Scientific Thinking Illuminate the Universe and the Modern World by Lisa Randall
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