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review 2017-09-21 14:12
Shitty Philosophy and Physics : “Time Reborn - From the Crisis in Physics to the Future of the Universe” by Lee Smolin
Time Reborn: From the Crisis in Physics to the Future of the Universe - Lee Smolin

“I propose that time and its passage are fundamental and real and the hopes and beliefs about timeless truths and timeless realms are mythology.”

 

 

In “Time Reborn - From the Crisis in Physics to the Future of the Universe” by Lee Smolin

 

 

Impermanence, Buddhist style?

 

Buddhism seems to acknowledge the play of opposites I've referred to elsewhere.

Recognising the yin-yang nature of the universe, in order to claim there is constant 'flux' (fluidity, rather than change; a subtle difference) - or for argument's sake, change - Buddhists balance that by asserting a 'greater' reality - the one, eternal, stable, whole (a supposed 'deeper' reality).

 

Contradiction and paradox is near the heart of evidenced, reasoned contemplation?

 

As for Aristotle:

time is a measurement of change is a measurement of time.

Change makes time possible, and vice-versa.

In principle, it seems that time persists, even in conditions of perfect stillness.

Yet any attempt to conceive a temporal progression, absent all change, seems to lead us into perplexing self-contradictions: any attempt to imagine how such unchanging time-flow could be measured, requires changing. It seems that time must be more than change; yet remove change, and time vanishes!  But if time is just a means to measure change, then in principle, it should permit the possibility of a world where change is cyclical. Yet our understanding seems to limit time to a linear, one way progression.

 

Or does it?

 

 

If you're into shitty physics, read on.

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review 2017-09-19 07:44
All Much Ado about Nothing: “The Trouble with Physics” by Lee Smolin
The Trouble with Physics: The Rise of String Theory, the Fall of a Science and What Comes Next - Lee Smolin

“The Weinberg-Salam model requires that the Higgs field exist and that it manifest itself as the new elementary particle called the Higgs boson, which carries the force associated with the Higgs field. Of all the predictions required by the unification of the electromagnetic and weak forces, only this one has not yet been verified.”

 

In “The Trouble with Physics” by Lee Smolin

 

 

Hello physicists and Lee Smolin in particular,

 

I can't say I agree with such a hard stance against string theory personally like Smolin does, but I’m what’s known as a stupid person, so it doesn’t really matter what I think. However, I do feel it is healthy for science to have people that challenge ideas from all sides. All this will do is galvanise people to work harder to provide evidence to prove or disprove any theory that tries to describe realty. Science thrives in areas of confliction.

 

Life is the memory of what happened before you died, i.e. we cannot extricate ourselves from the universe in any way shape or form, including our "objective," apparently repeatable theoretical notions. By definition, there is only one UNI-verse. If you want to call it a universe of multiverses or a multiverse of universes, or balls of string with no limits, no problem, but there is only one of everything that is and isn't. This assemblage of atoms, no different from any other atoms, called the human body, has a life and death, as do the stars; it also has an internal resonance we like to call the consciousness of self-awareness of existence. We all too often, de facto, accept that there is a universe outside our "selfs", our bodies, i.e. it’s just me, my-self, and I, and the universe that surrounds my body, as if there were a molecular separation of some sort. This starting point for science, i.e., this assumed separation from a universe that surrounds our (apparent) bodies is the first thing that has to go. By definition there is only one UNI-verse that includes Heisenberg, I, the photos and videos of flying objects that make apparently perfect right angle turns at thousands of miles per hour, which we casual observers are not able to identify, black holes, white holes, pink holes, blue holes, our memories, our records, not to mention everything else. It's all much ado about nothing. As someone else used to say, "This IS the cosmic drama," we are living at the interface of the Sun's outgoing light and the apparent incoming light from the universe that appears to surround the Sun. Ah, but, what if we live in a black hole and don't realize it? That would mean the night sky, which most of us consider to exist outside the sun would actually be all the light of the sun after doing a 180, except, and here's the kicker, daylight, i.e., the light of the sun that we experience as sunshine.

 

 

If you're into Physics and String Theory in particular, read on.

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review 2017-07-24 08:54
Plasma Physics, R.A. Cairns
Plasma physics - R.A. Cairns Plasma physics - R.A. Cairns

This makes a good second book on plasma physics - Chen's Introduction to Plasma Physics has yet to be beaten as a first book on the subject in my experience. But Cairns provides a good reference on the basics of a wide variety of theoretical approaches, phenomena, experimental methods and applications in plasma physics, admittedly requiring a much greater mathematical knowledge than Chen, but without being terrifying like Ichimaru's "Basic" Principles of Plasma Physics, which is anything but basic. A minor irritation is Cairns' use of the informal "goes as" for "proportional to." Not sure why it winds me up so, given I know perfectly well what he means.

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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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