Posts Tagged ‘the grand design’

The Grand Design (Part I)

December 28, 2010

I have always loved theoretical physics. I have been wanting to grab a physics book and read about any new theory or principle (chaos theory, string theory, M-theory, etc.), especially in quantum physics (the physics of small matter). New principles and theories started to accumulate and I felt like I was getting “behind” and I needed to catch up. But, a person in my position at a young startup finds it hard to allocate those precious moments of reading and researching. And coming from a computer science background, I have to do more reading and understanding than any physicist (and forget about the complexity of math that is associated with it). I came across Hawkin’s latest book “The Grand Design”, and wanted to read it. My fascination in physics was revived and I made a promise to myself that I will not just read the book, but I will also read about all the theories that it references until I have a good understanding of the whole concept proposed. Now that my laptop went crazy, I had to send it back to Dell to diagnose, and I found myself sitting here for a few days without coding. This was the perfect opportunity to finally get the book and start my quest. This post is not meant to be for scientific research. This is just my recollection of all the things that I read in the past few days from various books (I had to go back to read about Einstein’s general relativity to understand space curvature for example). I wanted to make this post as simple as possible, but sometimes it is hard to escape the “big words” that may confuse the average Joe. So, I decided to keep the post simple, but if I wanted to reference the big words, I would include a side note that starts with “Advanced”. You may skip those side notes if you are not fairly comfortable reading them and you won’t lose out.

The Grand Design is another physics book that was set out to explain the laws of the universe, to edge us closer to finding the Holy Grail of physics, the equation of everything, which is famously believed to be so simple and short that it would fit on a tshirt (and that is slowly changing to believing that maybe it is not just one equation but a few of them). Or, at least that is what physicists hope it would be. There are so many things to cover ahead of describing what this book is about, and so many things to say afterward. However, I am writing a post, not a scientific paper or a book like I said earlier. You will still have to do the further reading yourself to validate what I am saying or to learn more in detail.

In a nut shell, Hawkins (if you have never heard of him before then maybe you should stick to my other posts instead) states in his book that the universe did not need a helping hand from a divine “someone” in order to start rolling (or expanding). The biggest argument against physicists who are proponents of the new physics (string theory, general relativity, the big bang, etc.) was well if everything came from an extremely dense particle which exploded and expanded over a very short “period of time”, to form the universe, where did this particle come from? A very valid question given that physics itself firmly states that nothing comes from nothing (well until string theory came about, and I will describe it briefly in this post, where this line changed to: something can actually come from nothing provided that its total energy continues to be nothing). Then physicists replied and said: just because we don’t know the answer yet, that doesn’t mean we should give up trying and hand the credit to a divine “something”. Plus, if there was a God, who created him? And so on and so on. This debate was going on for thousands of years. With the new set of string theory variations (collectively referred to as M-theory), physicists now argue that they found the answer. Everything came from nothing and is going back to nothing! Very interesting considering this violates the first law of thermodynamics. Or, does it? How can energy come into “being” without coming from somewhere? The book took a bottom-top approach, by addressing all theories and laws that eventually contributed to the Grand statement toward the end of the book. I will do the exact opposite. I will make the statement, then dive into the corresponding explanation. If you have hung with me so far, put on your seat belt. We are going to address this right about…now.

The simplest possible term this can be put in is: “0 energy” is what this universe has in total! Even as we exist today, there is positive energy such as when work is being done on particles or objects, and there is negative energy when the particle does work and thus radiates energy away. The sum of those quantities across the universe is 0 as all positive energy cancels out the negative energy. The positive energy used to create matter as the universe started to expand was offset by the gravitational energy that wants to collapse the system back into a black hole.

Advanced: As for the matter itself (since mass and energy are interchangeable), no one knows what would cancel it out. That is where supersymmetry or super gravity theories (M-theory) came to be accepted because they state that the negative energy that is present in vacuum cancels out the positive energy of matter (although the math cannot be worked out yet with all the infinities, which is why M-theory is just a theory although with a lot of potential if proven to be finite).

Now, I am not going to dive into another big and controversial area which is “space” and “vacuum”. What is space made up of? There are many theories such as those that say space is occupied with small amounts of “virtual” particle pairs whose total sum of energy is 0 (this is what the M-theory proposes by suggesting that matter and force are two of the same, and thus there must exist something to cancel out the energy in all the matter that occupies the universe and its space). Those pairs include one particle and one antiparticle (of opposite charge) that simultaneously exist and then collide and disappear again (while radiating gamma rays). In summary, everything in the universe goes from mass to energy, back to mass, etc. And that we have equal amounts of positive energy as there is negative energy, totaling to 0.

— To be continued here