Thursday, November 30, 2006

Another Exercise in time wasting

You Are 81% Thankful

You're an incredibly thankful person, and everyone around you feels very appreciated.
You inspire people to be more optimistic, forgiving, and grateful.

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Tuesday, November 28, 2006

The thinking and the doing

The other day, I was doing what I seem to be doing a lot of these days, wasting time. The chosen method was blog hopping. I am new here and was just trying to see what is out there. In the process, I found something. I have found the same thing with the broad spectrum of people that I have shot the breeze over a few drinks with. People wax philosophical! If only you read what people wrote or talked about over a few drinks, 99% of the people in the world must be completely “analyzed” and hence incapable of doing stupid thinks that normal human beings that don’t see through their emotions do!

But this is clearly not true. All of these people do the stupid things that people do. I cannot say this for a fact about the blogsphere inhabitants, but most certainly about the people I know in real life. And, if the media, the movies and statistics are any measure, the people that I know are representative of the people out there. So, how does one reconcile these two facts? That is, people recognize the stupid things for what they are but continue to do them anyway?

The reconciliation lies in the fact that once one realizes something, one has to go through the exercise of putting it into practice. And the latter is the hard part. All of us know what the right thing to do is. All of us know that anger, disappointment etc are not emotions that are allowed logically. They originate from the ego and hence should not play any role in our lives. But, it is only the rare few who have the energy and application to turn this inherent knowledge into an everyday fact of life, like breathing or eating or something. I don’t think any of the above is very clearly put. But, I don’t have the energy to reread and edit it this just now.

Monday, November 27, 2006

Sevi Chelvam

This post is about the above Thirukural. I learnt this one when I was very young and it has always bothered me that Thrivalluvar picked out the sense of hearing as the supreme of all the senses we possess. The reason I was worried may be summarized as follows. Under most circumstances, one does not encounter great people or great thoughts "live" so to speak. Most great thinkers and their ideas I know through books. So, I thought that sight and the ability to read, the gift of language was most important in the advancement of one's maturity and knowledge.

But now, I have come to understand the choice of hearing as the supreme sense in the following way. The first, and probably the context directly relevant to Thiruvalluvar's thoughts, is that one understands and retains better the words that we hear rather than the words that we read. I have not yet sorted out why this is, but by empirical observation have concluded that this is indeed true. Perhaps the reason is that reading requires a greater application than hearing. The other context is a rather Freudian one. It is an accepted fact these days that conscious thought is the exception rather than the norm. Most of the processing in our brain and the origin of most of our actions is indeed unconscious. And clearly one can hear unconsciously, but one cannot read unconsciously. This ties in with the "greater application" statement made earlier. Hence what you hear is clearly the predominant part of what influences your thinking and actions. I don't know why I did not see this for many years.

Friday, November 24, 2006

Strong Emotions

It is a Friday afternoon after thanksgiving. I went to work this morning, dabbled around. Found more questions than answers, then came back home for lunch, a cigarette and green tea. Then, I started to watch a mushy movie about puppy love between a young boy and girl. I describe it as puppy love just because of how I have come to think about emotions of that sort. The movie was a reasonably realistic portrayal of how two people in love feel.

All of this started me thinking about passion. In the recent past I have come to think of passion of any kind as a negative emotion in the sense that if your actions are all driven by logical thinking and analysis, how can passion have any meaning? The answer is that passion is indeed meaningless if you are completely “analyzed” for want of a better word. One can of course talk about passion in lots of different contexts. But given where this story started let us stick to passion in relationships. In this context, I mean the feelings that one has when one falls in love for the first time. Then, if you stayed with the person for sufficiently long time, inducing these feelings requires stronger and stronger stimuli as the years pass. But, as stated earlier, these should play no significant role in how the relationship works. Even then, most couples never give up these feelings and hence the need to keep stimulating them.

The positive thing about giving up the urge to stimulate these emotions is that the passion comes with some associated baggage that manifest themselves as jealousy or possessiveness or something else, but generically, dissatisfaction of some kind. And I am living proof that if you stop trying to stimulate the “passion” part of things, the baggage drops off as well. But then, once in a way, and these days as I am living alone for the first time in my life and seem to be slightly depressed or suffering from apathy due to some other reason, more than once in a way, you feel nostalgia for when you could feel the way you used to.

Thursday, November 23, 2006

Statistical Mechanics and Elasticity

What is Elasticity theory? Given the strain on a solid, i.e., for a given macroscopic deformation, it tells you what the stresses in the solid are. There, as always, are two levels at which one studies the theory of elasticity. Suppose the constitutive relationship between the stress and strain is known, for example Hooke's law is a constitutive relation that is linear. Then, the problem is one of solving a set of differential equations to obtain the stress. When the theory is linear, as in the above case, this is simple exercise. The other level of study is associated with deriving this constitutive relation. This is the issue addressed in the rest of this rambling.

First, let us consider the context of an ordered crystalline solid. Further, let us assume that the solid is a defect free single crystal. The energy required to deform such a solid is set by the bonding energy that is primarily electrostatic. So, the thermal energy is much smaller than the typical energy scale in the problem. Therefore, a very good model for the solid would be a lattice of balls interconnected by stiff springs. In this case, the elasticity is linear up to very large applied stresses and the problem of getting a constitutive relation reduces to a Newtonian N particle problem that can be readily solved by going to generalized coordinates that are the normal modes of the system. Next, we ask, if we superpose thermal fluctuations on this answer, how is it changed? The result? It is not changed at all. This result is surprising at first sight, but is a rather obvious artifact of the harmonic nature of the interaction. One can readily verify this by writing down the partition function. The conclusion then is that for a perfect crystalline solid, statistical mechanics is irrelevant for understanding the elastic response of the system! You can hardly ever say this for a finite temperature N particle problem!

So, when does stat mech play a role in understanding elasticity of a crystalline solid? When there are defects in the solid. What happens is that as you increase the applied force on the solid, well before you probe the limits of the harmonic approximation made on the interaction, the defect gives. So, the response of this system is governed by what the defects do, rather than what the background perfect crystal is doing. The dynamics of defects in a solid is an elegantly formulated problem. A well developed theory exists a la E & M for understanding this. I don't know much about this so I will stop by saying that the problem of defect dynamics and defect interactions is a nicely formulated one that one can look up. The point of interest here is that the defects will now have a statistics associated with the temperature of the system. Therefore, in order to understand the elasticity of this system, one needs to take into account the fluctuations of the defects in the system. I don't know much about this either. But I mean to look it up and will tell you when I do.

So much for crystalline solids. There is of course a whole class of amorphous solids whose entire elasticity is statistical in origin, rubber being the standing prototype of this class. They are the reason I started thinking about elasticity and stat mech in the first place. But, I guess I must take another idle morning to sort this stuff out for myself.

Wednesday, November 22, 2006

The first post

I don't know why I am doing this. Well, come to think of it the previous statement applies to all things I do in life, so nothing too surprising about that. I guess I desperately need a hobby. And have decided to give blogging a try. We have to wait and see how this goes. I guess I am hoping that the illusion that somebody other than me is going to read this will give me the motivation to be more regular here than I am with a similar MS word file I have sitting on my laptop. Illusions, Illusions... And on that thought, here is a quote and more later.

Agent Smith: Why, Mr. Anderson? Why do you do it? Why get up? Why keep fighting? Do you believe you're fighting for something? For more that your survival? Can you tell me what it is? Do you even know? Is it freedom? Or truth? Perhaps peace? Yes? No? Could it be for love? Illusions, Mr. Anderson. Vagaries of perception. The temporary constructs of a feeble human intellect trying desperately to justify an existence that is without meaning or purpose. And
all of them as artificial as the Matrix itself, although only a human mind could invent something as insipid as love. You must be able to see it, Mr. Anderson. You must know it by now. You can't win. It's pointless to keep fighting. Why, Mr. Anderson? Why? Why do you persist?

Neo: Because I choose to.