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P A M Dirac

- Little Secrets
- Chosen Ones
- The New Husband
- Afterlife
- The Missing Sister
- The Southern Book Club's Guide to Slaying Vampires
- The Book of Longings
- Hidden Valley Road: Inside the Mind of an American Family
- The Sweeney Sisters
- Death in Her Hands
- Chosen Ones
- The Southern Book Club's Guide to Slaying Vampires
- A Bad Day for Sunshine
- Conjure Women
- If I Had Your Face

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A lot of stuff in the beginning is accessible and some of the later stuff is possibly accessible if you ve had a great teacher who followed this book and they won t because they find it excessively hard themselves in their course work Even Feynman said They had these great formulations in Dirac s book and in Heidler s I couldn t quite read the books They were too hard for me So if you are lulled into complacency that understanding everything that s in the book is something that you ll carefully read page by page, you are kidding yourself A lot of the stuff is simply ruminations on research that PAMD was doing then and some of it that wasn t Anyway, its a QM book for the mathematically proficient A QM book for researchers and mathematicians For all else, there s Shankar and Griffiths However, I d pick up the book for Chapter 1 alone Its concise and beautifully expressed.

Anything can be added commenting a book made by one of the fathers of quantum Mechanics and many other fields of knowledge A must for those who want to explore how to arrive to the deepest conclusions in physics An insight on their amazing way of looking to the worldWhat should be best to guide through this matter than one of its creators

Review of The Principles of Quantum Mechanics by P.A.M Dirac Oxford University Press 1958.The book is just over 300 pages including the Index It is of historical interest, mainly There are better treatments of the subject, but this is an original work and stands monumental in that regard, historically The originality and its place in history is this works strength and it stands on its own as a classic in modern theoretical physics, unmatched in many ways in that sense.This book was first published in 1930 In 1928, Dirac s application of the relativistic treatment of spin 1 2 particles leads to both positive and negative energy solutions to the electron This book was made new in paperback in 1981 It has been reprinted 9 times since The last reprinting was in 1993 It has a Preface to the first edition, which you should read using the Look Inside feature You can view the Contents of the book there, too There you will find that the book s contents are made up of twelve Chapters and a small Index.Quantum reality places the subject back into the study of the objective world Listen to the author in his own words This state of affairs is very satisfactory from a philosophical point of view, as implying an increasing recognition of the part played by the observer in himself introducing the regularities that appear in his observations, and a lack of arbitrariness in the ways of nature, but it makes things less easy for the learner of physics If, in your enquiry into quantum mechanics, you have read about these philosophical changes brought about from the discovery of quantum reality, then reading the words of one of its legends will reinforce why many modern physicist s sound like philosophers than physicists Here is the author, again, in his own words The methods of progress in theoretical physics have undergone a vast change during the present century The classical tradition has been to consider the world to be an association of observable objects particles, fluids, fields, etc moving about according to definite laws of force, so that one could form a mental picture in space and time of the whole scheme This led to a physics whose aim was to make assumptions about the mechanism and forces connecting these observable objects, to account for their behaviour in the simplest possible way It has become increasingly evident in recent times, however, that nature works on a different plan Her fundamental laws do not govern the world as it appears in our mental picture in any very direct way, but instead they control a substratum of which we cannot form a mental picture without introducing irrelevancies In Chapter X Theory of Radiation Dirac derives his theory of radiation in which he connects bosons to oscillators Relating a system S say a quantizied atom to its Hermitian operator Ho, he was able to identify the states of an assembly of bosons with the states of a set of oscillators This means that the dynamical system consisting of an assembly of similar bosons is equivalent to the dynamical system consisting of a set of scillators the two systems are just the same system looked at from two different points of view Dirac pg 228 229 Von Neumann, probably the greatest mathematician of the 20th century, in his book Mathematical Foundations of Quantum Mechanics , called Dirac s radiation theory one of the most beautiful achievements in the quantum mechanical field Von Neumann, pg 255 In the last chapter, the author solves both a positive energy and a negative energy solution for an equation now called the Dirac equation that applies relativistic solutions to the problem of particle physics, specifically, that of elementary spin 1 2 particles like the electron The positive energy solution is the electron The author doesn t ignore the negative energy solution, though This is one of the philosophical differences between quantum mechanics and classical mechanics Dirac simply allows the mathematical result of a negative energy solution to suggest that another particle actually exists in reality, every way equal to that of the electron, but opposite in sign This would be like an antimatter particle to the electron This would be unheard of but perhaps for science fiction writers Here is the author in his own words In this way we are lead to infer that the negative energy solutions of 56 refer to the motion of a new kind of particle having the mass of an electron and the opposite charge Such particles have been observed experimentally and are called positrons We cannot, however, simply assert that the negative energy solutions represent positrons, as this would make the dynamical relations all wrong For instance, it is certainly not true that a positron has a negative kinetic energy We must therefore establish the theory of the positrons on a somewhat different footing We assume that nearly all the negative energy states are occupied , with one electron in each state in accordance with the exclusion principle of Pauli An unoccupied negative energy state will now appear as something with a positive energy, since to make it disappear, i.e to fill it up, we should have to add to it an electron with negative energy We assume that these unoccupied negative energy states are the positrons The positron was confirmed by Carl Anderson just two short years later in 1932.P.A.M Dirac was an Englishman Since he is one of the early founders and contributors to Quantum Mechanics, I suggest that you read up on him if you haven t learned that much about him in the past I always appreciate a book if I know a little bit about the author In the Wiki on him I just learned that he married Eugene Wigner s sister Cool It is a small world.I hope I have peaked your interest enough to make a purchase today.

His insight into the physical interpretation of the formalism of Quantum Mechanics has no precedent Almost every physicist around the world agrees that HE IS MASTER DIRAC, so an insight into his vision of the theory is invaluable.This is not a didactic book, in fact, in my opinion, it is not even to be considered a text book Its value concerns the rigorous development of the formalism of QM, as well as a firm base for the understanding of the very principles of it I d say it s better for people who have struggling qith the ideas of QM for a while already, that for who are just starting with them.

It s the greatest text on quantum mechanics ever written