Notes on an Important Book — Another 5-Star Review

Posted by Pete J at on (remember remember) the 5th of November:

For anyone interested in how mysticism can be connected up with physics in a practical way, to the benefit of physics, and without any beating around the bush, this book may be a godsend.

The mathematics of quantum mechanics is well beyond the comprehension of most people and for the most part it goes straight over my head. This text book, which seems to be a thorough introduction to this mathematics, complete with challenging exercises, is therefore unlikely to become a popular best-seller. It is also expensive, having the worst word-to-price ratio of any book I’ve ever bought. However, I’m glad I bought it. It is possible even for the non-mathematician to see at least how the various mathematical approaches fit together and why they are needed, while the real heart of the book is the interpretation it places on the mathematics and this is explained economically and in plain English.

Quantum theory is astonishingly successful despite the utter lunacy of its mathematics, but it rules out any hope of our ever being able to conceive of what it describes by the use of everyday ‘classical’ concepts. We don’t have any other kind of concepts, so we cannot conceive of what it describes. Whatever it describes would have to be vastly more weird and wonderful than anything we observe in our everyday world. So what are we to do? Must we accept that the way have to describe Nature must always remain incomprehensible to us?

While explaining why interpretations of quantum mechanics that try to accommodate classical intuitions are impossible, rendering futile any hope of creating a picture in our heads of what lies behind the mathematics, Mohrhoff quotes Dennis Diecks, Professor of the Foundations and Philosophy of the Natural Sciences at Utrecht University.

“However, this is a negative result that only provides a starting-point for what really has to be done: something conceptually new has to be found, different from what we are familiar with. It is clear that this constructive task is a particularly difficult one, in which huge barriers (partly of a psychological nature) have to be overcome.”

Mohrhoff continues, ‘Something conceptually new has been found, and it is presented in this book.’ What is presented is a big idea. ‘What quantum mechanics is trying to tell us’, says Mohrhoff, ‘is that reality is structured from the top down.’ As something to think about this is probably worth the price of the book. It seems possible that as stated this is a one-sided view and that there are two equal and opposite ways of looking at this structure, as might seem more typical for the world-view of the Upanishads, but it hardly matters. What matters is that we can see from The World According to Quantum Mechanics that the ancient psychological, metaphysical and cosmological doctrine endorsed by Sri Aurobindo and his group would dove-tail perfectly with the mathematics of quantum mechanics and allow physics to be reconciled with metaphysics and mysticism.

The book is a vindication of Erwin Schrodinger, who concluded early on that the new physics he was helping to invent implied the truth of the advaita doctrine. With its publication it may not be unreasonable to think that for theoretical physics a paradigm shift may be approaching of even greater magnitude than quantum mechanics.

No need to make the world stranger than it is

Another review at, by Adrian Icazuriaga:

For those who have been following Mohrhoff’s revealing ideas during the last decade (the so called “Pondicherry Interpretation of Quantum Mechanics”), this book adds a few very important points to what is already one of the most comprehensive and consistent interpretations of the fundamental laws of physics that anyone has put forward up to the present date.

He obviously didn’t start this journey one fortunate Monday morning. He is following the steps of people like Bohr, Peres, Mermin and many other physicists who have contributed greatly to one and the same philosophical project: the de-reification of quantum-mechanical correlation laws, and the enormous implications that this carries for our understanding of physical reality.

This book is probably the best synthesis of that long-standing project. Its merit not only lies in taking a few isolated ideas about QM’s probability algorithms and integrate them into an overall consistent view, which would be a huge achievement in itself, but first and foremost, to explain classical mechanics and classical conservation laws as part of (in the limit of) that same fuzzy state of affairs.

In this way, he very cleverly differentiates between what an equation of continuity says and what a local conservation law is, basically “a feature of our calculational tools”. Key concepts like energy and momentum are introduced as underpinning the homogeneity of time and space respectively, instead of being just symbols in an abstract equation. On the other hand, the deceptive idea of force, deeply entrenched in our perception of a physical world, is redefined in a way that permits us to make sense of the Lorentz force law and the gravitational force as not being a mediating agent between causes and effects.

This is a profound, exhaustive and very well organized textbook, which should be of interest to anyone with a previous background in physics or, even better, to anyone who has not yet been contaminated by the mainstream habits and tricks of philosophy of science and crash undergraduate courses in QM. You won’t find here any of the fancy stuff that philosophers like to talk about (backwards causation, many minds, many worlds and many papers), but it will give you enough substance and plenty of material to think about for the next ten or twenty years. At the very least, it will give you the basic tools to approach any other interpretational strategy with the necessary dose of scepticism and awareness. As the author correctly stresses, there is “no need to make the world stranger than it is”.

The style is not as incisive and confrontational as most of Mohrhoff’s shorter works, which is a bit of a disappointment, but understandable giving that this book is aimed at the general public. In years to come, “The World According to Quantum Mechanics” will be taken for what it is: a serious and courageous challenge to our fundamental ideas about the fabric of space and matter.

Humbling experience

The following is a Review by Henning Dekant (Real Name) at (June 29, 2011).

Richard Feynman famously stated “I think it is safe to say that no one understands Quantum Mechanics.”

This book is changing that. Although so far I have only read up to chapter 5, it looks like this unexpected treatise lives up to its preposterous subtitle.

The way Ulrich Mohrhoff introduces QM everything flows from the basic rules of calculating with probabilities and the uncertainty relation. The latter in turn is a logical requirement for stable matter and quite a misnomer in English (surprisingly the original German term “Unschaerferelation” captures its meaning significantly better).

Reading chapter 5 has been a most humbling experience. I studied physics and have always been captivated by the particle wave dualism that the classical two slit experiment embodies so beautifully. Feynman observed that this “experiment has in it the heart of quantum mechanics”. Well, I feel like eating my heart out.

The way this book covers the two slit experiment everything falls into place and makes perfect sense. There is no wave particle dualism, just the naked necessity of a probabilistic regime. It is so simple. Painfully obvious. Easy to grasp with just a minimum of mathematical rigor. It boggles the mind that QM has not been understood this way from the get go. This feels like 20/20 hindsight writ large.

To add insult to injury, this is written as a text book that’ll be easily accessible for an enterprising high school student, because it briefly introduces all necessary mathematical tools along the way. I.e. a physicist can easily skip these parts as they are cleanly separated from the chapters in which the author executes his QM program.

If you’ve been trying to make sense of QM you will hate this book. It’ll make you feel stupid for not having been able to see this all along. Time to eat some humble pie.

I’ll report back once I read the rest.