Quantum Processes Systems, and Information 1st Edition

Quite frankly, quite simply, this text remains a favorite--of the more recent publications, this text and the one written by Mark Beck (Quantum Mechanics, OUP, 2012)-- battle for my attention. A cursory look at Fall 2022 undergraduate quantum physics courses offered at USA Universities shows that this text is not nearly well-enough known or utilized. What a pity ! This circumstance in 2022 ! Why so ?(1) Textbooks seem to come in two sizes: they are either too big or too small. Happily, not so here.You get twenty chapters spanning some 435 pages (excepting appendices). You get exercises (within sections) and you get problems (at the ends-of-chapters). That is excellent pedagogy (yes, I realize, Griffiths sort of does that too).(2) Happily, you will not get a mess of ambiguity focusing on linguistics. Read section #10.6 : "the wave-function is not a physical field like the air pressure...neither a field nor a probability distribution... it is a creature of a new and different sort." (page 220).(3) While this book is not explicitly advertised for self-study, I feel that a student embarking on a program of study would be well-advised to study it. So, if this text is not required in your course, get it anyhow !If you can multiply 2X2 matrices and are familiar with the log function (in any base), then initial chapters will pose no issues (exercise 2.13, page 25, will ask you to verify through matrix multiplication). Read: "The particle can carry a 'secret message' encoded in its spin state. If we read the particle in the right way, the message is revealed." (page 36). Information and Q-bits, these terms are introduced early and often.(4) Chapter three, that is the obligatory, compulsory, abstract mathematics (of Hilbert space). Amusingly, chapter three of Griffiths (1995, first edition) gets there too, around the same time (Linear Algebra). There is more pedagogy: "...the easiest way to prove a fact about abstract operators is to work with their matrix representations." (page 64). More pedagogy: revisit spin one-half (pages 28-36) with more "justification."(see, page 73). Chapter one started with information, chapter four continues that theme (pages 79-97).(5) Read: "In a measurement process, we extract information from a quantum system. But, what sort of information is it ? Exactly what does a measurement tell us ? Uncertainty relations are better thought of as "indeterminacy relations." (page 96). Learn why the authors say that in chapter four. Pedagogy again is displayed page 103: utilize dimensional analysis (exercise 5.6). Now, read: "It is a curious thing that time is not itself an observable quantity in quantum theory. Find a nice discussion here (pages 105-107).(6) A problem introduces the so-called Baker-Campbell-Hausdorff identity (5.8, page 116). An excursion to entanglement is offered chapter six: "entanglement is generally the result of dynamical interaction." (page 121). Bell's theorem introduced: "we must either give up the idea that determinate hidden variables underlie the indeterminacy of quantum systems, or we must give up the idea that widely separated parts of the Universe act independently." (page 133-135).(7) Chapter seven continues the theme of "information." No-cloning theorem and teleportation are here.(8) I like exercise 8.17 (page 167). You are asked to compare the proof here to the previous encounter of the same proof ! That is, chapter eight will refer you back to chapter 4, basic de-coding theorem(page 82).Excellent pedagogy ! Ninth chapter, Open Systems. Read: "...we can often ignore the rest of the world.." (page 182). Here is wisdom: "The signs in equation 9.36 are a customary, if slightly confusing convention."That is a recap of the 'first law of thermodynamics.' Section 9.4 (heat and work) is a thoughtful prelude.(9) Previous to chapter ten, we have been "discrete." Time to get "continuous." Reading: "....Infinity is just a simplified way of describing a quantity that is immense, but still finite." (page 202). Herein Schrodinger equation and probability "flow." (page 226). Problem 11.13 revisits your vector identities for the goal of showing a relation for "total probability." (page 246). That is excellent pedagogy !(10) Generalizing spin is chapter 12: "...reverse our logic..." Here: elaboration of spin-angular- momentum. Brief introduction to isospin concludes the chapter. Learning a "conceptual puzzle" regards electrons and entanglement: "we have permission to think of two identical particles as distinct subsystems, provided that there is some physical observable that can be used as an effective label. (page 303). There is more of Schrodinger (in one-dimension) next (revisiting chapter 10 and 11). This material is situated later than is usual in many textbooks at undergraduate-level (for example: Griffiths chapter two). Three-dimensions, that means Hydrogen atom, up next (here page 342; Griffiths gets there early, page 134). Revisit quantum information in chapter 18 (pay close attention to figure 18.1, is there an error in the figure ?). A focus will be an introduction to dynamics, that is, quantum computing (information processing). Excellent !(11) Concluding: After an all too- lengthy review (I got excited all over again), I can only say, get the book and study it. Exposition is lucid. Exercises and problems are invaluable. The textbook is pedagogic and highly recommended !

The book came with scratched cover and stains on several pages.

Best quantum mechanics textbook I have ever come across. This is a great introduction to quantum mechanics because of the way it addresses all of quantum theory through the lens of quantum information. Thinking from this point of view helps demystify concepts such as wave particle duality and the uncertainty principle which really helps beginners better understand quantum mechanics and gain intuition for quantum phenomena. This book is also great for someone who already knows a good deal of quantum mechanics, but don't expect to find too much hardcore phenomenology. This book is really heavily invested in concepts rather than surveying and explaining in detail a great deal of complicated quantum mechanics experiments. I was into my fourth semester of quantum mechanics courses when I read this and I was struck by all the profound insights and exercises in this book. I have never before seen such a clear and compact look at thermodynamics and quantum information elsewhere. I have personally recommended this book to several of my peers.

The only book you will need on quantum systems

Excellent introduction to the quantum theory for first acquaintace, but more, it goes deeply into the notions of information and information transfer. Very useful for entering the subject.

Excellent book with a number of fantastic exercises that support the material.