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review 2017-06-19 08:58
An Introduction to Magnetohydrodynamics, P.A. Davidson
An Introduction to Magnetohydrodynamics - P.A. DAVIDSON,E.J. Hinch,S.H. Davis,Mark J. Ablowitz

So magnetohydrodynamics (MHD) is the (classical) theory of electrically conducting fluids, which divide neatly into liquid metals and plasmas. I'm not professionally interested in liquid metals so I skipped all the material that was solely applicable to them, which is possibly as much as half of it. It's also a microcosm of one of the many problems with the book -it's scope is way too large for it's size. To get anywhere with a topic that is defined as the merging of fluid mechanics and classical electrodynamics, one must have a thorough grounding in both those separate topics first. This book tries to cover that and does it badly because they need a book each. The physics of plasmas is very different from that of liquid metals but this book tries to cover both. So really we have four books' worth of material crammed into the space of only one. That's one problem.

 

Next there's the mathematical treatment, which is really poor. The subject requires a strong grasp of vector calculus. This is unavoidable. The fundamental equations of the theory are non-linear and form a large set that must be solved "self-consistently" whilst describing a dynamic (i.e. time varying) system. This also, is unavoidable. In other words this ain't no easy subject. That's no excuse for lax derivations, poor or absent definitions, or equations that are actually useless because one of the parameters in them has to be "chosen appropriately" (i.e. fudged) in every specific case, with no means of doing so so much as hinted at.

 

Finally, the verbal description of the physics is on occasions horrendously bad (and plain wrong). This is particularly so with regard to energy, which is repeatly "destroyed" throughout the book - a task nobody else has been able to accomplish in the history of physics. The author seems simply not to know what happens to the kinetic energy of the fluids he describes when it stops being obviously visible. Heat, man! Heat! Conservation of angular momentum is similarly and even more cavalierly treated.

I can't recommend this book to anybody, unfortunately.

 

I have a number of other books that treat MHD. In some it's an introductory chapter, in others it's in relation to a specific context (naturally occurring plasmas). Whether these will prove better remains to be seen.

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review 2017-06-08 09:12
Time Series Analysis and its Applications, Shumway and Stoffer
Time Series Analysis and Its Applications: With R Examples (Springer Texts in Statistics) - David S. Stoffer,Robert H. Shumway

I read the first ~100p of this book. I stopped because the subject matter had diverged too far from my area of immediate interest (which was covered in the first chapter) rather than because the book is bad. In fact I think it is a good introduction to the topic for those with an interest and a background covering "normal" statistics to a level most STEM undergrads would have. Perhaps one thing that became obvious to me by inference should have been made explicit at the outset, which is that the fundamental general approach is as follows:

 

1. Get time series and plot it.
2. Guess any trends and/or periodicities in the data (various methods)
3. Subtract them (various methods)
4. Examine what's left ("residuals") to see if it behaves like noise (i.e. has some known type of random distribution) (various methods)
5. If it does, YAY! You have a usable model of the time series
6. If it does not, either make further guesses about trends/periodicities in the residuals and repeat from step 2 OR
7. Go back to the original time series and start from step 2 with different guesses about the nature of trends/periodicities

 

A flow chart of this at the beginning of the book would make what the book is actually about crystal clear.

 

As mentioned in a status update, the book does not assume the reader is scientifically motivated and does not discuss the meaning or validity of any trends, correlations or periodicities discovered. There are applications where this is entirely legitimate, probably the biggest and most utilised being analysis of financial/economic data for purposes of investment or trading: One only needs a model that works and not an explanation of why it works in order to make practical decisions. I would advise budding scientists to approach with caution, however; this form of analysis can only generate empirical models and hypotheses about why they are true are a separate but essential part of the scientific process. So, for example, if one discovers a model of the form, seasonal oscillation + white noise, describing your time series, one can make predictions about the future but there is no explanation of why the seasonal variation occurs. You are only part way there, scientifically.

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review 2017-05-20 19:48
For readers with a good attention span who enjoy Hitchcockian suspense set within the world of science and books about writers
The Planck Factor - Debbi Mack

I write this review as a member of Rosie’s Book Review Team and thank Rosie Amber and the author for providing me with an ARC copy of this book that I freely decided to review.

This thriller (technothriller according to Amazon) tells a complex story, or rather, tells several not so complex stories in a format that can make readers’ minds spin. A thriller about a student who decides, on a dare, to write a genre book (a thriller) and whose life becomes itself another thriller, one that seems to mix spies, conspiracies, terrorism, the possibility of the end of the world, and it all relates to quantum physics. (Or, as she describes it in the book: “…a suspense story with a hint of science fiction and a touch of espionage at its heart.”) The parallelisms between the story of Jessica Evans (the protagonist) and that of her fictional character, Alexis, become more convoluted and puzzling as the book progresses and the astounding coincidences will ring some alarm bells until we get to the end and… It is a bit difficult to talk about the book in depth without giving away any spoilers, but I’ll try my hardest.

This book will be particularly interesting for writers, not only because of its storytelling technique (talk about metafiction) but also because of the way the main protagonist (a concept difficult to define but Jessica is the one who occupies the most pages in the book and her story is told in the first person) keeps talking (and typing) about books and writing. No matter how difficult and tough things get, she has to keep writing, as it helps her think and it also seems to have a therapeutic effect on her. It is full of insider jokes and comments familiar to all of us who write and read about writing, as it mentions and pokes fun at rules (“Show, don’t tell. Weave in backstory. Truisms, guides, rules, pointers—call them what you will… And adverbs. Never use an adverb.”) and also follows and at the same time subverts genre rules (we have a reluctant heroine, well, two, varied MacGuffins and red herrings, mysteries, secrets, traitors and unexpected villains… and, oh yes, that final twist).

Each one of the chapters starts with the name of the person whose point of view that chapter is told about —apart from Alexis’s story, told in the third person, written in different typography, and usually clearly introduced, there are chapters from the point of view of two men who follow Jessica, so we know more than her, another rule to maintain suspense, and also from the point of view of somebody called Kevin, who sounds pretty suspicious— and apart from Jessica’s, all the rest are in the third person, so although the structure is somewhat complex and the stories have similarities and a certain degree of crossover, there is signposting, although one needs to pay attention. Overall, the book’s structure brought to my mind Heart of Darkness (where several frames envelop the main story) or the Cabinet of Dr Caligary (although it is less dark than either of those).

As you read the story, you’ll probably wonder about things that might not fit in, plot holes, or events that will make you wonder (the usual trope of the amateur who finds information much easier than several highly specialised government agencies is taken to its extremes, and some of the characteristics of the writing can be amusing or annoying at times, although, whose story are we reading?) but the ending will make you reconsider the whole thing. (I noticed how the characters never walked, they: “slid out”, “shimmied out”, “pounded”, “bounded down the steps”, “clamored down”…) As for the final twist, I suspected it, but I had read several reviews by other members of the team and kept a watchful eye on the proceedings. I don’t think it will be evident to anybody reading the story totally afresh.

The novel is too short for us to get more than a passing understanding and connection with the main character, especially as a big part of it is devoted to her fictional novel, (although the first person helps) and there are so many twists, secrets and agents and double-agents that we do not truly know any of the secondary characters well enough to care. Action takes precedence over psychological depth and although we might wonder about alliances, betrayals and truths and lies, there are no complex motivations or traumas at play.

Due to the nature of the mystery, the novel will also be of interest to those who enjoy stories with a scientific background, particularly Physics (although I don’t know enough about quantum physics to comment on its accuracy). A detailed knowledge of the subject is not necessary to follow the book but I suspect it will be particularly amusing to those who have a better understanding of the theory behind it. (The author does not claim expertise and thanks those who helped her with the research in her acknowledgements). The book also touches on serious subjects, including moral and ethical issues behind scientific research and the responsibility of individuals versus that of the state regarding public safety. But do not let that put you off. The book is a short, fast and action-driven story that requires a good attention span and will be particularly enjoyed by writers and readers who enjoy complex, puzzle-like mysteries, or more accurately, those who like stories that are like Russian dolls or Chinese boxes.

I enjoyed this book that is clever and knowing, and I’d recommend in particular to readers who are also writers or enjoy books about writers, to those who like conspiracies, spies and mysteries, especially those with a backstory of science and physics, and to people who prefer plot-driven books and who love Hitchcock, Highsmith and Murder She Wrote.

 

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review 2017-04-25 05:53
Paul Dirac, Peter Goddard (editor)
Paul Dirac: The Man and His Work - Abraham Pais

Note the sub-title: this book consists of four lectures about Dirac, his work and developments from it in physics and mathematics, plus Hawking's laughably ignorant memorial address. (He repeatedly insulted his hosts for delaying for 11 years an event that was, in fact, only one year beyond the minimum requirement of ten years post Dirac's death.)

 

Only the first lecture is really biographical and even that takes time out to discuss Dirac's scientific contributions. From there the book gets progressively more technically challenging, ending with a lecture on the Dirac operator and spinors that in detail is going to be incomprehensible to anyone without an advanced working knowledge of topology. (The gist is that we have no clue what spinors mean, geometrically, in the way we know what vectors and tensors are, for example.)

 

In between, there's good stuff on antimatter from prediction to present day understanding and similarly Dirac's magnetic monopoles then to now.

 

Much of this book will go over the heads of the casual reader and if you want anything more than a cursory biography, you will also need to look elsewhere, but for physicists, it's a worthwhile publication.

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review 2017-04-22 10:51
Albert Einstein, Frieda Wishinsky
Albert Einstein - Frieda Wishinsky

If one respects the fact that this series is aimed at young people (young enough to need things like "geometry" and "Fascism" defined for them) then I think this is quite a good little book. It's short and inevitably superficial but I'm not sure how it could be anything else considering the intended audience. Nevertheless it gives an insight into Einstein's character and at least an indication of the significance of some of his work.

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