Saturday, 3 September 2011

Book review: A Briefer History of Time by Stephen Hawking with Leonard Mlodinow

Hmm, where to start now? I don’t really love cosmos at the beginning. I just enjoy looking into the sky to find stars even though I can’t tell their names, positions or characteristics at all. I just look at them to know sometimes they cover the sky, sometimes they don’t, some of them are bright, others are not.

There are some personal stuff at the beginning of this post. If you don't have time and just want to jump into the book review, please go directly to the paragraph beginning with "I make a backup plan that having the book in two languages for safety, LOL".

Recently, after departing to Canada, I started to notice the difference on sky between my motherland and Canada. Even though I personally feel like the sky looks larger, clearer and closer in here (Canada), I still can’t find any day that the sky is completely covered by stars like in my motherland. How weird!

Another fact that maybe I’m lucky to live with a partner who loves cosmos at the best of his life. He listens to most of Quirk and Quark shows on CBC (by Bob McDonald). He could stop talking to sit and watch Discovery channel for hours even though he was in other interesting topics (e.g: Mr. Jack Layton of NPD party, his idol). Sometimes we discuss about cosmos and tons of questions running back and forth without any answers. Gradually, I stepped in some aspects of cosmos just by time without knowing.

There were some days in July when the moon reached the biggest size observing from the earth, I borrowed someone a pair of binoculars and gazed the sky many days. I even began thinking about buying telescopes but of course it never happens since the price is bigger than my empty pocket now.

Suddenly one day, browsing YouTube, I found two interesting topics, one was about Einstein and another one was about Bermuda. Voraciously, I watched them all in two days.  

The series of 3 clips about Bermuda here: And around 9 or 10 video clips for Einstein start with this clip:
I was also expecting to answer some questions in my mind by watching them. However, the bad news is, after watching them all, even more questions coming. I was struggling to understand the relativity theory from Einstein but it was really tough. Thus, I did some exercises to google that theory in both English and my mother tongue. Reading Wiki a couple of times and still couldn’t get it. The topic was abandoned awhile there.

Around one or 2 months later, I found a facebook share about scientist contest. It’s simple - just answer 10 questions if you can name correctly 10 alive scientists. Of course I can’t name more than 3 by my own. I did some cheating by googling their names with image for fun and I got 8 right answers, LOL. You can try, who knows: The good thing from that contest is – you can read about those scientists’ biology afterwards. I was interested in Stephen Hawking since he’s the person I see a lot from media. Reading through some articles of him, my eyes were caught by some books whose names really stimulate my curiosity, such as, “A brief history of time” or “Universe in a nutshell.” Hah, interesting!

Of course I want to read those books. Nevertheless, saying is always easier than doing in this case since I know those books are not really simple for a reader like me; a person with no physic or cosmos foundation. Worse, if any bit of physic I know, it should come from my mother tongue, not English. Anyway, just make a try, don’t lose anything anyway except a little free time I have in my own time machine. Who knows what I can gain.

The book starts with 4 easy chapters. These chapters mostly explain about the history and awareness of beings about cosmos. Mentioning from the time people believed that the earth flat and be supported by turtles laid on turtles, after that people believe the earth was the centre of universe, Newton theory and so on. They’re simple since I learned them here and there. Anyway, it’s still good to read these chapters since the author explains more details with beautiful illustrations. It will be missing if I don’t mention that those 4 chapters also gave me the encouragement to read more since I know I can get through the book now. 

Chapter 5 and 6 are the ones I’m expecting now. They explain about relativity from Einstein. In a different situation from the time I watched them on YouTube, I can understand the theory now. I imagined and linked with YouTube clips more clearly while reading through the chapters. Now, I know what all the experiments meant and the way they setup the observation stations to prove Einstein’s theory in YouTube video clips: light is bent in curve space. This chapter answers well my curious question as mentioning above.  I’ve got some satisfaction so far.  

Chapter 7 is rather thrilling by just the way it’s named: the expanding universe. This chapter introduces me about galaxies. How galaxies are different from each other, how big the galaxy should be, where the earth is sitting in our galaxy (Milky Way), how people find galaxies, how many galaxies out there in our universe, etc. Of course all answers are not completely proved but the chapter gives my imagination the wings to fly. The chapter helps me a lot to understand why most of stars just lie at one side of the sky when observing from the earth. This chapter reminds me again some other questions put into the discussion with my partner: why the universe is expanding but not crunching? What caused the Big Bang? Is our universe just one of tons of universe out there? The author illustrates universe as a balloon in this chapter. Just imagine a balloon with wrinkles and some black spots representing for galaxies. If we keep blowing the balloon up, the galaxies will go farther to each other and wrinkles will get straight out. As much the universe expands, as weaker the force between galaxies. Right now, the ball isn’t blown at the biggest size yet so it still can expand.

Now, it’s time to jump into some definitions of black holes and the cause of Big Bang by going through chapter 8. The book explains why most people just agree that there was a Big Bang at the beginning of the universe. The first simple reason is the time before of universe is just cut out of scientists’ researching models temporarily since they want to find out the earth’s destiny first. The second reason is, since the point of time was put outside of researching models, seem like a Big Bang is the most reasonable explanation for now.

Black holes were also described pretty detail in this chapter. Some beginning concepts of black holes like: what makes a black hole, what is inside black holes, how scientists find black holes, how big black holes are, how many of them out there, where they are usually located in the universe. There are three points impressing me around black holes:
  • Usually, in the centre of galaxy is a big black hole
  • Black holes are not completely black and lights can’t escape from black holes
  • The end of a star is usually a black hole but not always. Some of stars may explode and cause a supernova which can be observed from the earth if they’re close enough to the earth. The book said the last supernova was recorded in the Milky Way around 1604. At that time, night can be seen like day during many days. Average supernova explosion happens once in a particular galaxy in one century, of course that’s just average, we still didn’t see any supernova from the Milky Way since 1604. The leading candidate for the next supernova explosion in our galaxy is a star called Rho Cassiopeiae. A supernova can erase our earth completely if it’s close enough. Fortunately, the next supernova candidate is around 10,000 light years away from us, pretty safe.

The rest of chapter 8, I was interested in a statement that time on the earth is more slowly than in space. Or another way to say, two people holding two similar clocks, one person on the earth and one is around 1 second of light speed in the space (far from the earth), the clock of the person on the earth always ticks first. This leads to the concept of twin paradox: if there is a twin, one lives on the earth and one lives on space, after some decades, the person on the earth will be much older than the one on the space.

Chapter 9 is the one I don’t really understand the most of concepts. The chapter mentions about quantum gravity. I just vaguely know that scientists make the new theory (quantum) just to find a way to measure light and energy of huge objects (like stars, galaxies and universes) to avoid infinite loop of the older physic laws. They made some experiments on electron, photon, proton, and anti versions of them to observe how they act when shooting some short rays on. By those experiments, they can find the way to simulate and create machines which detect radiations from universes. Afterwards, they can calculate the object distances, characteristics and so on. Scientists also tried to explain about light under different physic theories like wave or particles and they’ve been struggling to unify all those different physic laws so far.

Wormhole is a new concept in chapter 10. This concept makes me smile since scientists picked “worm” to name the concept which is exactly the same as the idea of my worm family in this virtual internet space. Wormholes were given to explain the possibility of time travel. The chapter was discussing around possibilities of travelling to the past and the future if they find some shortcuts called wormholes. This made me think about the Bermuda myth when one pilot said he seemed to travel thousands of miles just in 3 minutes and he felt himself inside a huge tube which floating his flight extremely fast.

Science generally or physics particularly so far was made one by one from all real observations and experiments. And since one by one was created scattering here and there, they sometimes conflict to each other. Chapter 11 explains the effort of scientists to unify physic theories and laws. They work around if the universe were created with a set of laws or no such unification at all.

Here are some last words.

After chapter 6, I tended to read two books, “a briefer history of time” in English and “a brief history of time” in my mother tongue. Therefore, from the review above, I may mix the contents of chapters a little bit because two books arrange them in different ways. If you find such a thing like that, please take it easy and forgive my bad. Enjoy the book!

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