Member

This book highlights foundational issues in theoretical physics in an informal, open style of lecture. It expresses the flow of ideas in physics -- from the period of Galileo and Newton to the contemporary ideas of the quantum and relativity theories, astrophysics and cosmology -- as explanations for the laws of matter. Rather than presenting the ideas of physics as a fait accompli, the book leaves it up to the reader to decide which of these 20th-century ideas in science will carry over to the 21st century for our further comprehension of the laws of nature in all domains, from that of elementary particles to cosmology.

It is the contention of the author that our future progress in physics comprehension will only take place when the foundational controversies between the quantum and relativity theories are recognized and discussion is given to their resolution. The book, therefore, presents an attitude not normally taken in other present-day books on subjects in contemporary theoretical physics and cosmology.

This book describes a paradigm change in modern physics from the philosophy and mathematical expression of the quantum theory to those of general relativity. The approach applies to all domains - from elementary particles to cosmology. The change is from the positivistic views in which atomism, nondeterminism and measurement are fundamental, to a holistic view in realism, wherein matter - electrons, galaxies, - are correlated modes of a single continuum, the universe. A field that unifies electromagnetism, gravity and inertia is demonstrated explicitly, with new predictions, in terms of quaternion and spinor field equations in a curved spacetime. Quantum mechanics emerges as a linear, flatspace approximation for the equations of inertia in general relativity.

Reviews:

"This book differs from the many other books on the same topics in three essential points: 1st, it concentrates on the historical development of the question of the unification of quantum theory and gravity, 2nd, it uses the quaternion approach to describe the metric and other geometric objects, and 3rd, it is a quite personal book... a very readable monograph, containing also philosophical issues, considerations about electromagnetism, and unified field theory." (Hans-J?rgen Schmidt, Zentralblatt MATH, Vol. 1052, 2005)

"The basic attempt of this book is to initiate a study of a single, coherent theory of matter applicable to all domains, from elementary particle physics to cosmology... This very interesting and clearly written book is even readable by a final years student in physics. The presentation is very well got-up... I highly recommend this excellent work to every theoretical physicist interested in general relativity and unified field theories." (Fernand Dhoore, Physicalia, Vol. 57 (3), 2005)

"Sachs' book is a fascinating exposition of how an approximation in general relativity brings out quantum mechanical features. Perhaps Einstein would have been greatly interested... I think it should be read by anyone who is interested in quantum mechanics and gravity." (J. Hartley, Contemporary Physics, Vol. 45 (6), 2004)

This volume consists of a selection of refereed invited lectures presented at the International Workshop on Mach?s Principle and the Origin of Inertia which was held at the Indian Institute of Technology, Kharagpur, India, as a part of the golden Jubilee celebrations of the Institute, from February 6 to 8, 2002. The Workshop was organized by the Centre for Theoretical Physics of the Institute with Prof. A.R. Roy as the Organising Secretary. It also includes a few contributions from experts who could not attend the Workshop. Inertia is one of the main physical properties of all bodies. Its origin poses problems of a fundamental nature. Ernst Mach proposed that the inertia of any body is caused by its interaction with the rest of the Universe. The idea reflects a deep connection between the cosmos at large and its individual constituent bodies, thereby implying a holistic conception of nature. On the whole, Ernst Mach had a seminal influence on the evolution of Physics in the 20th Century, and will influence the future development of Physics in the 21st Century. It is interesting that many of his ideas play a role (directly and indirectly) in opposite positions within contemporary physics. His epistemological viewpoint of positivism clearly influenced the basis of quantum mechanics. On the other hand his non-atomistic model of matter and the accompanying interpretation of inertial mass (the ?Mach Principle?) influenced the holistic approach of the continuous field concept of the theory of general relativity, as a general theory of matter. The contributions to these proceedings demonstrate Mach?s influence on contemporary thinking. For we see here the views of an international group of scholars on the implications of Mach?s principle in physics and astrophysics. The ideas presented here could affect the path of study in physics for many generations to come.

Contents:

• Preface
• Acknowledgements
• Jayant Narlikar: A Tribute to Fred Hoyle
• Mendel Sachs: The Mach Principle and the Origin of Inertia from General Relativity
• Amitabha Ghosh: Extension of Mach?s Principle and Cosmological Consequences
• James F. Woodward: The Technical End of Mach?s Principle
• A.K.T. Assis: The Relationship between Mach?s Principle and the Principle of Physical Proportions
• W. Farrell Edwards: Inertial Mass of the Electron
• A.R. Prasanna: Mach?s Principle and Inertial Forces in General Relativity
• Jorge Guala Valverde and Ra?l A. Rapacioli: Inertial Mass in a Machian Framework
• Horst-Heino v. Borzeszkowski and Renate Wahsner: Mach?s Principle and the Dualism of Space-Time and Matter
• C.S. Unnikrishnan: Experiments Motivated by Mach?s Principle: A Review with Comments
• D.F. Roscoe: A Perspective on Mach?s Principle and the Consequent Discovery of Major New Phenomenology in Spiral Discs
• T.P. Singh: Mach?s Principle and Quantum Mechanics Without Spacetime
• H. Broberg: Mass and Gravitation in a Machian Universe
• George Galeczki: Mach?s Principle and the True Continuum

Relativity In our Time concerns the relevance of Einstein's theory to human relations in contemporary times. lt is physics and it is philosophy. lt is a discussion about one of the greatest of all pillars of 20th century thought and science. Based on a seminar course for a mixture of science and humanities students, the approach and narrative style leads the reader towards the frontier of thinking in this farreaching subject. Sachs deals with the whole spread of relativity, starting from the early history of Galileo and Faraday, he arrives at the foundation of the special theory. There is a logical transition to the general theory while the last part of the book covers the mind-testing realms of unified field theory, Mach's principle and cosmology. The book begins with atomistic, deterministic, classical physics and goes on towards a view of continuous fields of matter and a clearer view of spacetime. The reader is led into Einstein's extension of this theory towards a unified force field; consequently the authors address the issue of the validity of linear mathematics compared with the realism of a non- linear universe.; Such arguments today are leading towards a new paradigm in science - a study and description of nonlinear natural systems especially far from equilibrium systems; their energetics and dynamics. This book should be of value to postgraduates, undergraduates, secondary students and professionals in physics and philosophy and anyone with an interest in science subjects.

Einstein Versus Bohr is unlike other books on science written by experts for non-experts, becuase it presents the history of science in terms of problems, conflicts, contradictions, and arguments.

Science normally "keeps a tidy shop window but a messy workshop."  Professor Mendel Sachs breaks with convention by taking us into the theoretical workshop, giving us a problem-oriented account of modern physics, an account which concentrates on underlying concepts and debate.  This book contains mathematical explanations, but is so designed that the whole argument can be followed with the math omitted.

Professor Sachs's story begins with classical and nineteenth-centruy physics, decribes the early discoveries in particle theory, and introduces the "old" quantum theory which evolved into the quantum mechanics of the Copenhagen School.

Such important ideas as the Einstein Photon Box Experiment, the Einstein-Podolsky-Rosen Paradox, and the Schr?dinger's Cat Paradox are clearly expounded, followed by a completely fresh explanation of relativity in conceptual terms. showing how apparent paradoxes can be removed by Einstein's own interpretation, especially that of his later years.

Professor Sachs gives a detailed comparison of the fundamentals of the quantum and relativity theories, suggesting how the contradictions might be resolved.  In an epilogue, he makes suggestions, with reference to religious notions, Taoism, and Buber's theory of I-Thou, for generalizing Einstein's approach beyond physics.

`...to read it should be a rewarding experience for anyone who is concerned with understanding the most fundamental features of the physicist's world view. ...well written and contains some very useful material on both the conceptual and technical aspects of relativity.' Foundations of Physics, 15 (1985)

This book on the history of science is a fascinating, informative account of man's effort to find an all-encompassing, unified theory that would explain the nature of the universe.  From the time of the Greek philosophers the subject of continuous versus discrete theories of matter have been vehemently debated.

In the intervening centuries our knowledge of the universe has increased many times over and although we have solved many mysteries, we have uncovered others.  THE SEARCH FOR A THEORY OF MATTER explores in an enlightening, readable way how first one theory, then another was proposed, how some have reappeared after being discarded, how attempts have been made to fuse apparently contradictory theories into a unified and cogent explanation.

Ranging from the physics of ancient Greece through Galileo's studies of freely falling bodies, Newton's laws of motion and gravitation, Faraday's field concept, the theories of Maxwell and Boltzmann, the experiment of Michelson and Morley, to Einstein's theory of relativity, Bohr's model of the atom and the modern quantum theory, Dr. Sachs examines and illuminates man's attempts to gather the laws that govern the motion of objects, electricity, magnetism, optics, gravitation and atomic and elementary particle physics into a unified theory of matter.

The book is suitable for senior high school students, college freshman and all other readers interested in discussions of the important concepts and conflicts of ideas that have appeared throughout the history of physics, highlighting the developments in the twentieth century. - Inside cover