double happiness!

I'm really happy for my sister. Both my sister and her now-husband are so amazing! I'm glad that things are moving ahead in their lives. I'm also glad that I can now refer to the amazingly intelligent, considerate and decisive (and lucky) Oliver Wicker as my brother-in-law instead of "just" my sister's boyfriend(which has a somewhat transient feel to it, even though they've been together for so long!). And I can refer to Kitty as "my sister-in-law... sort of" instead of the awkward "my sister's boyfriend's sister" which somehow seems more distant than it feels. During the wedding reception(which was a high tea), I had the chance to sit with and talk to people around 9 years older than me. It's quite remarkable how... "steady" (forgive my diction) they seem! Conversation flows easily and casually even between strangers - they know what questions to ask to simulate a friendly chat, and how to respond in a witty manner. I wonder if it's because they are in the same age group and they have a better idea of what the concerns of people of that age are? Or perhaps making friendly conversation with people they've just met is a universal skill they've acquired over time? That seems like a really useful thing to learn. Sitting at that table I keep feeling that they know a great deal about life that I don't, but they are all pretty cautious about giving advice. For a while after the reception I felt like I was the most immature of the bunch of people at the reception (well maybe excepting the one year olds), and wondered: Do all x year-olds talk like x year-olds? I don't want to be sound young and immature! Is there any way around it? And my mom told me: It can only come with experience, through success, failure, or even suffering, and all that will take time. Of two people of the same age, one can sound like old when talking about one thing, but he'll probably sound younger when talking about another, as the time they have will tend to equalize the amount of experience they have, and no experience has greater intrinsic worth over another, be it success or failure. Oh well, I guess I can only wait then!

Brought about by change

I just identified the background music in NLB when they announce "Dear readers, the library will be closing in 15 mins, …) it's moonlight sonata! -------------------------------- Today, when I received some change from a waitress, I was reminded of this story by my primary school teacher: there was once a student who didn't really know etiquette. So everyday, when the student submitted a notebook containing his homework to his teacher, the teacher would toss it aside and walk away without any explanation. This made the student frustrated yet puzzled. Every day he would greet the teacher, or say something nice before submitting his homework, but the teacher did the same thing: toss it aside, and walk away. It was only one day when he finally, by chance, decided to try handing in his homework with both hands that the teacher finally accepted it. So, according to my teacher, the moral of the story is: it's more polite to hand things over with both hands. But the obvious thing in the mind of the student would be: Why doesn't the teacher just tell me what I'm doing wrong? Perhaps, the student could also have watched how other students were handing in their homework to try to figure out what he was doing wrongly. That reminds me of an article about reinforcement learning vs imitation vs instruction. The article found reinforcement learning to be less effective than both imitation and instruction for a certain task. It makes me wonder: if machines become conscious, would they get frustrated when we try to train them to do something by reinforcement learning? Would they think, "Yeh right, as if you know how to do it!" or "Why don't you just tell me what you want and not make me do this over and over again?" But I guess there will always be some amount of reinforcement learning to be done as long as there are unsolved problems - some people need to stay at the forefront to do less inefficient learning task of discovering new methods, while others can help to spread the knowledge in a more efficient way by making more people aware of the method, or by teaching it well. Perhaps the moral of the story is that Nature is kinda like that annoying teacher in that story, and we as students should help to make each others' lives a bit easier.

a new hope?

This is the 500th post! I can't believe that this blog has survived so long. Unfortunately, nothing epic is going to happen here (Then again, 500 is only special because we have 2 hands, 5 fingers, and Indian merchants were smart). This is just a test for a web service called "IntenseDebate", which I think seems pretty cool. Really! Nothing much to see here.

I do hope that overseas Singaporeans stop giving people the impression that Singapore is a dictatorship/totalitarian/authoritarian/despotic state.

What prompted me to write this post is that some of my schoolmates from USA thought that Singapore isn't a democracy - they were genuinely surprised to hear from me that Singapore holds elections at all. When I asked them, "What gave you the impression that Singapore is not a democracy?" The response: "Even the other Singaporeans whom I've talked to don't seem to think that Singapore is a democracy."

I find it rather curious why some people from the US get the impression from Singaporeans that Singapore is some sort of an outright dictatorship. It is a matter of fact that Singapore is a democracy. Leaders are chosen by elections. Leaders are accountable to the people. Citizens have civil rights. What is left as a matter of opinion is the extent to which the above three are true, and whether that means that Singapore is "truly" a democracy.

I cannot generalize this to all overseas Singaporeans, of course, but from the ~5 Singaporeans whom I have encountered describing Singapore to Americans, I get the impression that they tend to be too eager to state why Singapore is not "truly" a democracy, but forget to mention that Singapore is a democracy in the first place. While another Singaporean will understand that Singapore isn't run by Mussolini/Hilter/Mao, someone who hasn't heard much about Singapore might have a different idea in mind when one says, "Well, we don't exactly have free speech, we are known for really strict laws, and the ruling party has been ruling since independence."

Why do we (the ~5 people we have met and admittedly, myself initially) so spontaneously speak of how Singapore isn't "exactly" a democracy before we even state that it is one? My guess is that Singaporeans are used to talking about Singapore-style democracy in the context where they are arguing about the finer points with other Singaporeans, who are well aware of and are used to all the rights that they have in Singapore. The largely pro-government mainstream media wouldn't hesitate to remind us that the government is accountable to the people. The rulers wouldn't hesitate to remind us that they are, after all, chosen by the people fair and square. The truth is not entirely that. Given these information as the basis to agree upon or to critique, New media and coffee-shop talks balance out the dominant influences of public opinion with a primarily anti-government stance to arrive at something that is more accurate.

The effect of this context of pro-government media is that when discussing Singapore politics, a Singaporean subconsciously assumes that the listener already knows some big things about Singapore. We are already used to doing all kinds of things with few state-enforced consequences, the things that we cannot do without consequences are particularly salient. We pretty much take our rights for granted. As such, we are used to talking about the rights we don't have and how elections aren't exactly fair, rather than the rights we do have.

This works fine in Singapore, because everyone lives here and has some intuitive idea of how "oppressed" we are. But when someone who is used to thinking of and talking about Singapore politics this way will be misleading to people who haven't heard much of Singapore. Without the preconception of all the things you can do in Singapore, it gives a rather negative and inaccurate impression.

I cannot prescribe what one should say to others about Singapore. After all, what I say is also mostly my own opinions. But I do hope that when Singaporeans talk to other people about Singapore politics, do consider that people might assume the worst if you only state what is not good.

PS: Another observation is that Malaysians tend to give a more positive portrayal of Singapore than Singaporeans themselves do. Maybe we can learn from them to produce a more balanced "pitch" about Singapore politics.

Are exclamation marks outdated? CAPS LOCK IS QUITE GOOD AT GIVING THE IMPRESSION OF SHOUTING. In fact, from the first word of the 'capped' sentence that you read, you would already know that there is some shouting going in, whereas if you were reading a sentence that ends with an exclamation mark, you would have no idea that the sentence was meant to be emphasized, leading to only the last couple of marks "sounding louder" in your inner voice!

Five minutes


Can I summarize each course that I took last year in about five minutes? Let's see.

Classical Mechanics:
- Principle of Least Action is equivalent to Newton's Laws.
- Principle of Least Action goes like this: there is a quantity called "Action", which is a function of a trajectory(real or hypothetical). Only trajectories with an extremum action are physically possible.
- If you have N degrees of freedom, you can use this principle to write N equations of motion. Just plug the Lagrangian into Euler's equation.
- If there are constraint forces, find an excuse to put the constraint into the Langrangian (by adding "zero" times a Langrange multiplier). The magnitude of the Lagrange multiplier give you an idea of how "strong" the constraint force is.
- You can rewrite the Lagrangian in another form. Applying the Legendre transform gives the Hamiltonian. The point of doing this is to make it easier to express equations of motion in terms of momentum. You also get first order differential equations instead of second order ones. (Doesn't make it easier to solve though, since they are typically coupled for non-trivial cases)
- Noether's theorem - the coolest thing of all. "Every symmetry has a corresponding conservation law." It sounds like something that came out of Dao De Jing (ok maybe not that much). E.g., if shifting your setup in the x-direction isn't going to affect its motion, then this means that x-momentum is conserved. So this theorem links every displacement with some kind of momentum. BUT! The weirdest thing is, time is associated with Energy! Really interesting, and this will become significant later.
- Central force motion and Scattering. Some mathematical tricks, many useful formulae that you probably shouldn't try to derive by yourself during a midterm. Landau is brilliant, read each page many times.
- Oscillations with driving forces, damping forces and coupling. Driving forces - use Fourier transformation for periodic driving forces, use Green's function for the general case, Laplace transform works well too. Damping forces - memorize/refer to solutions of this kind of second order ODE, and be comfortable with complex exponents, trig functions and hyperbolic trig functions. Coupling - make small oscillation approximations, dump it into a matrix and solve the eigenvalue/eigenfunction problem. Maple/Mathematica is your friend. If coupling is weak, approximate generously.
- Non-intertial frames and rigid body motion. Nightmare fuel. Remember Euler's equations, remember how to use them. Developing an intuition, while not wholly rigorous, helps to prevent sign errors and saves time. There's also a magical equation, "d/dt|_inertial = d/dt|_body - omega cross", which nobody seems to know how to derive but somehow works marvelously well.
- Special relativity. The relativistic Lagrangian is -gamma mc^2. You can obtain it by doing a Legendre transform on total relativistic energy. All the above tricks apply, except that rigid bodies aren't so rigid anymore.

Multivariable Calc:
- Langrage multipliers are cool.
- The Hessian determinant is useful for checking whether a stationary point is max, min, saddle, or degenerate. Take note of boundary points.
- The Jacobian determinant is useful for doing multiple integrals. It's important to set the integral up properly.
- Line integrals - find a new parameter to describe the line, and integrate along it. Remember to take the dot product.
- Surface integrals - find two parameters to describe the surface, and integrate along them. Remember to take the cross product. Be careful with the orientation, or use intuition to check the answer and reverse-engineer the sign.
- Curl of grad is zero, div of curl is zero.
- There are three different manifestations of the "fundamental theorem of calculus" -  a relationship between differentiation and integration. 1) If the vector field has zero curl, it's possible to express it as a grad of some scalar field. It's the relationship between gradient and line integral. 2) Divergence theorem expresses the relationship between divergence and volume integral. 3) Stokes' theorem expresses the relationship between curl and surface integral.

Social Psych:
- There are different ways of doing social psych research - typically analyzing data and doing experiments. There are advantages and limitations to all approaches. Note experimental biases, cultural differences, observer effects. Studies may be value-laden. They might also be conducted in unethical ways. Most studies quoted in this course are done in the US, so what is true there might not be true elsewhere.
- The "self" is a more fluid construct with East Asians than it is with Americans - i.e., different situations, different "self".
- Many biases - "Better than average" phenomenon is one of them. Tendency to warp perception/interpretation of reality to make oneself feel better.
- Situational influence -> Mechanism --> Phenomenon --> Effect. Two common mechanisms are arousal and rationalization.
- Attitudes influence behaviour, but behaviour can also influence attitudes. Some powerful persuasion techniques make use of this.
- Persuasion could take central route or peripheral route. Which route works better depends on a number of factors.
- Conformity and Obedience - [Asch, Milgram expt] Most people can be made to conform under the right circumstances (though there is always some who don't conform). A few factors that affect the degree of conformity/obedience have been found.
- Attraction - people are typically more attracted to those they meet more often and that they are more similar to.
- People form groups quite easily, and tend to bias against the outgroup.
- Stereotypes influence people's perceptions unconsciously but significantly. Approaches have been found to reduce this.

General computer science(Java)
A bit of the following:
- Elementary types and operations, Arrays, If else, loops, methods and arguments, recursion, classes and objects, scope and encapsulation, using data types, creating data types, linked lists, using interfaces, order of growth(time/resources), insertion sort vs mergesort, computability, tractability, P versus NP.

Writing seminar
- UNCLEAR THESIS/MOTIVE WILL BREAK AN ESSAY
- Read the source before critiquing it (instead of referring to someone else's critique)
- There are ways to twist a quotation to suit your purpose.
- Sometimes there's just no correct answer.
- Good stitching helps to make a essay more "flowy", which is good.

(To be continued)