Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts

Sunday, 16 July 2023

15 million Degrees: A Journey to the Centre of the Sun - Professor Lucie Green (2016)

 

Rating: Excellent

Without gravity there would be no solid matter in the universe, just energy and particles floating around, and without stars there would be nothing but hydrogen, helium and lithium, elements formed shortly after the Big Bang. Many of the heavy elements we find in the universe today are forged within stars like our sun, Sol. I've always regarded stars with some fascination, they are the alchemists of the universe and, in the case of Sol, the source of the energy that life has needed to evolve and flourish on Earth. Really, if humans really must have gods, its the creative forges that are the stars. 15 Million Degrees is a thorough overview of everything you need to know about our Sun and more, including the pioneer scientists who slowly built knowledge about Sol, not just in the core where fusion occurs, but also in the other layers of the Sun, all of which have their own characteristics and complexities. Without going into detail (it would be best to read this book), the Sun is an extremely complex object with features such as the photosphere, the corona, the heliosphere and the magnetosphere. There's convection zones, sunspots, plasma, the radiation zone, and my favourite, the flux ropes, which are magnetic field lines that have been twisted by the intense movements of the Sun's rotation, trapping the plasma and taking it on a wild ride. 

Just some of the Sun's structural features

Professor Green is an engaging writer, conveying not only her own enthusiasm and research about Sol, but also everything that is known about the Sun and what is theorised but not proven as yet. The chapter about sunspots is particularly fascinating. Sunspots can be readily observed and it turns out that they reveal a great deal about how the Sun functions, including the Sun's eleven year cycle of activity and how it behaves magnetically. There are many facts about the Sun that would astound the average person, for example, the heliosphere helps to shield the Earth from interstellar radiation, which would otherwise damage DNA and possibly make life untenable; essentially we live inside the atmosphere of the Sun. Coranal mass ejections are another incredible phenomenon, as the Sun's magnetic forces eject mass equivalent to that of Mt Everest from the surface of the Sun and into the solar system. Known as space weather, such phenomena can have profound effects on Earth and if one should directly interact with Earth at this point in history, then most of our electronic equipment would suddenly cease to function, fortunately temporarily, but with great cost to the economy. My only real criticism of 15 Million Degrees is that there could have been more photos and plates throughout, in particular a better map of the different parts of the Sun for easy reference. Otherwise this is an absorbing and illuminating read, no pun intended, but you get it anyway.

Sunday, 29 January 2023

Helgoland - Carlo Rovelli (2020)

 

Rating: Excellent

Carlo Rovelli is an Italian theoretical physicist who has written a number of fascinating books about quantum theory, some of which are still languishing unread in my collection, but I bought Helgoland recently on a trip to Melbourne and, for some intuitive reason, I needed to read it now rather than later. I'm pleased that I did. Rovelli is an important physicist who has worked on the problem of linking classical physics with quantum physics, developing the theory of loop quantum gravity (not the subject of this book). Helgoland begins with Werner Heisenberg's allergy lead retreat to the German island of Helgoland in 1925, where he worked on the the mysteries of atomic behaviour and came up with the observational interpretation of quantum theory. Such insights led directly to the famous thought experiment by Erwin Schrödinger concerning the cat in the box that could either be alive or dead until it is observed. Here's where Rovelli comes in, with the relational interpretation of quantum mechanics, which helps to deal with the problem of reality needing an observer in order to collapse the probability wave functions of the quantum realm into solid observable 'reality'. Confused? Well, first I'd advise you to read one of the best books about quantum theory for the lay-person, Quantum Theory Cannot Hurt You by Marcus Chown (2005), and then read Helgoland. Cutting to the chase, however, relational interpretation posits that as quantum objects interact with other quantum objects, they are 'observed' in the course of interacting. Reality is like a hall of mirrors. In this regard Rovelli's arguments appear sound and compelling.

Heisenberg, had bad allergies

Rovelli is a fine writer, able to convey difficult concepts in a way that can be deciphered by the average person. In my opinion getting some kind of grasp on quantum physics is essential for having a deeper relationship with the universe, and therefore, reality. Rovelli also ventures into philosophical territory, but in a manner that avoids potential eye-rolling. The characters than founded quantum theory are also fascinating characters, Heisenberg, Bohr, Born, Einstein, Engels and Schrödinger, among others, are worth reading about in their own right. Rovelli touches upon these physicists in regards to how they reacted to Heisenberg's insights (that were then backed up by experiments), and it is a compelling story, one that continues today, as Rovelli is just one in a long line of thinkers to tackle quantum mechanic's mysteries. If the relational interpretation of quantum mechanics is correct, then the implications are massive, including doing away with the need for an observer (in terms of humans, life and 'God'). It also, quite possibly, makes the concept that all probabilities exist all at once, with most hidden in parallel universes, redundant. It's a theory that always seemed ridiculous to me. In any case, although Helgoland does not need someone to be reading it for it to exist, go out and buy a copy and give it a read, it will spark those synapses and change the way you view the world.

Helgoland, had no pollen





Monday, 31 May 2021

The Planets - Andrew Cohen and Brian Cox (2019)

 


Rating: Admirable

I bought this book thinking that it would give me a quick update on everything that has been discovered about the solar system in recent times. It turns out that I've actually been keeping up with most recent discoveries, however for those that haven't been keeping up, or know very little about our family of planets trapped in the gravity-well of old Sol, then this book would a good place to start. The Planets gives a fairly straight forward summation about each planet by, in most cases, grouping them together and discussing them related to each other, the exceptions being Jupiter and Saturn. Most of the various significant moons and the astroid belt get a look in as well. The basic facts and the more astounding aspects of each planet are presented in easily digestible chapters. Also featured are informative tables and quotes from scientists meant to either underline the main points or to engender a feeling of profundity, although this didn't always work for me, but perhaps I'm a bit jaded in this regard, or perhaps the font was just too small for my middle-aged eyes.

The surface of Titan

One of the best features of The Planets is the focus on the the history of planetary exploration via highlighting the incredible stories of the probes humanity has sent out into the solar system, such as Pioneer 10, Mariner 4 and the two Voyagers. Such achievements are truly significant and without these probes our knowledge of the planets would be quite paltry. Of particular interest is the story of the Messenger probe, which undertook a remarkable journey to investigate the planet Mercury, which is a much more fascinating planet than most people would expect. There's also the Cassini probe, which explored Saturn, at the same time launching the much smaller Huygens probe onto the surface of my favourite moon - Titan. I remember that era of exploration clearly and it was great to read a fairly detailed account of their discoveries. However, detail, or lack of it in some cases, is also a flaw of the book. Obviously The Planets is a fairly generalised account of our solar system, but considering just how little was known about Pluto before the arrival of the New Horizons probe in 2015 there is scant detail about this amazing 'dwarf planet'. There was also little information about the trans Plutonian objects, such as Eris and Makemake. Although this is more understandable considering we have not visited them, some extrapolation would have added something extra to what was a rather truncated end to an otherwise useful and at times inspiring account of what is essentially our home turf in this galaxy of ours.

Pluto: more information please


Monday, 28 July 2014

The Demon Haunted World: Science as a Candle in the Dark - Carl Sagan (1996)




Rating: Excellent

Carl Sagan was one of a select group of scientists who could successfully communicate complex scientific notions to laypersons. Sagan was an important cosmologist and astrophysicist, but it is his popular science books and documentary television series Cosmos (1980) that will be remembered by the general population. The Demon Haunted World was his last published work before his untimely death in 1996. I remember that my reaction to his death was one of sadness and but also of appreciation. Sagan achieved a great deal while he was alive and in doing so influenced me greatly in my outlook on life and my understanding of the universe.

In the preface to The Demon Haunted World, entitled ‘My teachers’, Sagan talks about how much his parents taught and encouraged him even though they were laypeople with no knowledge of science. They supported his dream to be an astronomer and inspired him with their down to earth skepticism and sense of wonder. Sagan did a similar thing for me when I watched Cosmos at the impressionable age of ten. Cosmos inspired me and nurtured my fascination with astronomy and the world around me, something that, like Sagan, was supported by my parents. In the latter chapters of The Demon Haunted World Sagan talks about the importance of not only education, but of having books in the home; something that is essential to providing that ‘candle in the dark’, keeping spurious pseudo-science and superstition at bay. As a librarian I greatly appreciate Sagan’s stance. As a society we must never lose sight of the importance of providing egalitarian access to books and information, in particular for the young.

Throughout the main body of The Demon Haunted World Sagan’s debunking of pseudoscience is eloquent and, for the most part, compelling. Many of the initial chapters concentrate on UFOs and alien abduction; in particular the typical UFO stories and the so called face of Mars. The publication of The Demon Haunted World coincided with the era of The X-Files and a plethora of pre-millennial conspiracy theories. Once again there is a personal connection here for me, having been a UFO and alien obsessive during my childhood in the 1970‘s. Spurred on by UFO and alien books and classic 1970’s movies such as E.T, Close Encounters of the Third Kind and 2001 A Space Odyssey, like Mulder I wanted to believe. I even had my own strong memory of seeing a large white cigar shaped UFO hovering over my neighbour’s backyard that I’m sure was real, but would have just been a dream (I dreamt about UFO’s constantly). Curiously one of the scientific explanations for alien visitations and abductions that Sagan puts forward is sleep paralysis, something I experienced during my teenage years, although I didn’t see aliens (what I did see is another story).


The Demon Haunted World
is a fascinating read, but can also be a sobering one. Sagan’s passionate argument for a better educated population is profound  and important. Sagan reminds us that it is essential to know something of logic and science (amongst other subjects) in order to make sound decisions. Unfortunately the statistics Sagan quotes regarding knowledge, beliefs and education in his home country of America is truly appalling. Only 9% of Americans accept that humans evolved; half of Americans do not know that the Earth orbits the Sun in a year and 63 % of American adults think that humans lived alongside dinosaurs. These statistics are from the 1990’s; would they have improved in the last twenty years or so? Unfortunately I doubt it.

Nearly twenty years after the publication of The Demon Haunted World Sagan’s argument against blind belief and pseudo-science is more important than ever. When it comes to the pressing issue of climate change humanity is at the crossroads and climate change deniers around the world, including the Abbott led conservative government here in Australia (perhaps the worst offenders of all), could benefit from reading this book. Science is under attack more than ever by non-scientists with dubious agendas and flawed belief systems who portray science and scientists as untrustworthy. The great irony, as Sagan shows, is that scientists go to extreme lengths to make sure that their findings are as accurate as they can possibly be and therefore, by extension, their conclusions too. When it comes to climate change it seems that we still do live in a demon haunted world. 

Finally, perhaps the best thing about reading The Demon Haunted World was discovering that Sagan and I shared a very similar outlook toward science. Sagan states early on that: “In its encounter with nature, science invariably elicits a sense of reverence and awe. The very act of of understanding is a celebration of joining, merging, even on a very modest scale, with the magnificence of the Cosmos.” Science and a sense of wonder, even a sense of mysticism, are not mutually exclusive. Science is not merely cold reductionism, but provides a deep understanding of the magnificence of the cosmos and therefore of human existence itself.