As someone who watched the fabulous series "Cosmos: A Personal Voyage" by the late, great Carl Sagan, I wasn't sure whether to watch the 2014 series version "Cosmos: A Spacetime Odyssey" (hosted by Neil deGrasse Tyson) but I was very quickly sold after the first episode. It had been many years since the original series, which I watched in Mexico, around 1981 (one of the more than 60 countries where it was broadcast). In my opinion, there are few TV shows of this type. Given how much I liked the new version of Cosmos, this book was near the top of my "want to read" list.
So I borrowed the e-book at the first opportunity I had as it seemed quite enjoyable from its premise and it did live up to its billing. Using a rating scale defined in another blog with book reviews, I give it a 4/5 stars.
What follows are some of the facts I learned from it.
Back in 2011, I wrote a post in one of my other blogs (titled in Spanish Gotas de Datos) about the detection of anti-matter which was related to the monitoring of gamma rays. This passage gives more context to the phenomenon of gamma rays flashes. Interestingly enough, the origin of these flashes is still a bit of a mystery:
The planet Saturn has always interested me (I wrote 5 posts on the beautiful planet in Gotas de Datos, starting 12 years ago, when NASA's spacecraft Cassini was on a mission to study it), and I would really like to observe it someday through a telescope to see if my eyes are good enough to detect that it is an "oblate spheroid", as its speed rotation will be something out of my perception reach.
I wish the following type of facts about some elements of the periodic table were taught in school. Fortunately, deGrasse Tyson, gives us stories with a human interest for einsteinium, selenium, tellurium and technetium.
From further readings in Wikipedia about einsteinium, it's not a big leap to assume that Albert Einstein knew about the discovery of the new element named in his honour (given the dates of the events). Although he did not live to see it officially named after him, I can imagine that had he been alive it would have been a very bittersweet recognition of his work. (Same goes for Enrico Fermi whose work was recognized with the element named after him: fermium. This element was discovered through the same process and by the same team that worked on einsteinium).
The story of the elements selenium and tellurium was romantically described. I'm sure that if they had told me the relationships between elements like this during my old chemistry classes, I would have paid more attention and they would have been easier to remember. Technetium, on the other hand, has a very intriguing story behind it, quite appropriate for a sci-fi novel (another of my favourite genres in literature).
And the story of helium was also a surprise. Who knew that its name was so well applied! But what was most amazing to me is to learn that it has been the only element discovered outside Earth.
Whenever dark energy and dark matter are mentioned, I always assumed that they were total mysteries in physics. It was interesting to learn that although dark energy cannot be explained as such, it can be measured and calculated. But what I find most amazing is knowing that the greatest error in Einstein's theory can actually be seen as a "meta-error".
Another thing I find mystifying is that what can be seen in the universe as regular matter is only one twentieth of all the matter. All the planets, stars and galaxies account for so little! There is such a big gap in our knowledge and understanding of the universe.
Following is a good description of the reason why dark matter is mysterious and a source of discussion, and why the conservation laws are well established and confirmed not just on Earth but in the universe.
I was able to get a little more context and clarity on some definitions in the Wikipedia article on the Cosmological constant, but it is all still way above my understanding. If anyone wanted to get a list of related articles and themes on this subject, the Cosmology Portal of Wikipedia could be a good place to start.
The author reminds us of the power in the scientific process: "Science is not just about seeing, it's about measuring, preferably with something that's not your own eyes, which are inextricably conjoined with the baggage of your brain. That baggage is more often than not a satchel of preconceived ideas, post-conceived notions, and outright bias". One more reason why I would so like to see our society guided more by science than by politics, public relations or marketing. But I digress...
The question that was news to me is that maybe what is not understood so well is gravity rather than dark matter. And the fact that dark matter varies significantly in different environments was also a surprising piece of information.
The following section is interesting in that it describes all the things that are not dark matter. And to finish the last line "In our own solar system, for example, everything that is not the Sun adds up to to 0.2%". That is all what all the planets, moons, asteroids, etc. amount to in our own system, such a minuscule part of the whole. (NASA has a great overview page with 10 fascinating facts about our Sun).
It's so lucky for us that the Sun as well as Earth's atmosphere and magnetic field protect us from cosmic rays. And it is also surprising that their origin is still a mystery.
Our view of the universe has changed so much during my lifetime, that I would not even know where to begin to list the examples of how our cosmic perspective has expanded. So, I found that what the author admits rather humbly in the next paragraph is, in my opinion, the best example that can be given.
I really liked the quote that "after the laws of physics everything else is opinion". But I also found very useful the other statements which are great reminders to keep in mind always:
The author gives us a good example of the basis for saying that the laws of physics are universal. I still find it amazing that through science we can expect alien civilizations to be operating under the same laws:
The best description I've read of the hadron relevance:
Another subatomic particle, the boson, was defined with an interesting human perspective, as I had no idea of the origin of its name. And searching later on about Satyendra Nath Bose, I learned of yet another example of the kind of geniuses that India has given to the world.
The literary origin for the word "quark" (baptized by the physicist who proposed its existence, Murray Gell-Mann - a scientist with many fascinating facets himself) was also a surprise, but what I found funny was the slight hint of evidence of superiority or disdain from the author toward the naming conventions used by other scientists.
It's hard for me to remember the relationships between the subatomic particles, but I found this paragraph a good introduction to some member of their family:
To end this summary, I will add as a reference the following diagram of the Standard model, which is not from the book, but it is a good visual categorization of the subatomic particles that make up our universe:
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| Model diagram by MissMJ - June 27, 2006, Wikimedia |
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