## A hilarious reply to referee.August 2, 2009

Posted by keithkchan in fun stuffs.

For some totally irrelevant reason, I found an hilarious reply to the referee’s report on Martin White’s web page. Fortunately, I haven’t encountered such funny referees and editors. If you are not so fortunately, you may want to imitate this reply. Probably you need to acknowledge the original author Roy F. Baumeister. Besides that, I don’t know what you can do. Maybe submit it to another journal.

## Reactable – a new tool to electronic musicJune 24, 2009

Posted by keithkchan in fun stuffs.

My colleague Mr Sjoert (and James) sent me the link to an interesting electronic music generation tool. First have a look at the following Youtube video

When you put the modules on the table they glow and interact with each other to generate sound. You can either add more blocks to it and/or move the blocks to generate new effects. You can just create music by hands. I don’t know if you can program the interaction between the blocks yourself or not. It is cool, isn’t it? For more details see Reactable’s web site.

## The elegant beggarsJune 23, 2009

Posted by keithkchan in fun stuffs, Philosophy.

I am pretty busy these days, for no good reasons as usual. But I have to say something on this blog. This time let me say something I find totally ridiculous here in New York (or America).

The beggars people usually have in mind, at least I have in mind, are usually humble and pitiful. But this is not the case in New York. Beggars can be found everywhere here, particularly in the subway. I find it very annoying because I commute by subway everyday.

“Ladies and gentleman, sorry for disturbing you. My name is Peter. I am homeless, jobless. I am hungry. I have XYZ disease. Blah, blah, blah… I am grateful if you can give me some money or change.” Then the guy goes around the compartment to collect money when somebody is kind enough to give them money. The guy then goes to another compartment to continue his speech. The guy’s voice is loud and clear despite the fact that the guy claims himself to be “sick and hungry”. From the speech, I get the impression that the guy’s voice is energetic and confident, it sounds we have the responsibilities to pay him. Most of the time the beggars decently, sometimes they wear better than I do. In one occasion, the beggar wears a suit, isn’t it totally ridiculous? Should I call them gentlemen instead of beggars?

Most of the time I ignore them. But some people are “kind” enough to give them money. Let’s estimate how much money they make. From my observation, they get on average one dollar in each compartment in the train. Suppose this takes, say 5 minutes. So they make 12 dollars in one hour. Let’s assume they work 8 hours in one day. They make 96 dollars in one day. If somebody gets about 100 dollars a day, how likely that he suffers from hunger? That’s totally ridiculous. In fact, they make more money than I do! As a poor graduate student, I only get 70 dollars each day from the stipend. So I am poorer than a beggar!

So I will say those people who pay these beggars are not kind, but stupid. Almost all those people who ask for money are stronger and bigger than me, and have no apparent disabilities. OK, if they want to find a job in Wall Street, it can be difficult. I don’t think it is so difficult to get a job in McDonalds’ or in a pizzeria. They don’t do it because those stupid people keep on paying them money. This “job” as a beggar is easier and maybe more profitable than being a worker in a restaurant.

My observation is only limited to New York City. I don’t know if this is a local phenomenon, or it also occur in other parts of America. This is one of the ridiculous things I find in New York.

## From spin to mechanical osicillationJune 14, 2009

Posted by keithkchan in fun stuffs, Journal club.

I haven’t updated the blog for some time, so I should say something now.
Well, there is a rather interesting report appear in Nature, Entangled mechanical oscillators. You can you find it on arXiv 0901.4779.

You probably have heard of quantum entanglement many times, which means that the state is not factorizable. A famous example is the Schr$\ddot{o}$dinger’s cat. Measurement causes the wave function to collapse. When you do measurement you either push the cat to the hell or drag it out of the hell. But this is still a thought experiment. Not just because physicists are kind to animals, but also it is impossible to do it on macroscopic scales because of decoherence. All the examples I heard of are limited to entanglement of spin or polarization. But in this the Nature report, a group of physicists at NIST have managed to convert spin entanglement to mechanical oscillations. The experimental details are technical, and I don’t really understand. In (and only in) simple terms, they first entangle the spin of two magnesium and two beryllium ions, and then separate them into two potential wells. In each well, there is one magnesium and one beryllium ion, which form an oscillator in the potential well. They then carry some measurements which create the motional entangle state. I don’t understand how they really do it. For those interested in, you should consult their paper.

The significance of this paper is they have for the first time created mechanical entangled states. This is one important step towards Schr$\ddot{o}$dinger. But, cats, no panic, there may be still 500 steps away.

Incidentally, there is an article in Science describing this paper. The article is fine. But don’t read the comments if you don’t know much about this subject. I find them dubious, if not totally ridiculous. You may want to check it against John Baez’s crackpot index.

## Earliest Pornography!?May 16, 2009

Posted by keithkchan in fun stuffs.

Sometimes it is appropriate to talk about porn. Here is one of the occasion. You can find porn easily today. But it is interesting to ask how early people have explicit interest in porn. The article, whose title is the Earliest Pornography? sheds new light to this question. A group in Germany unearthed a female statuette, dated back to more than 35000 years by carbon dating, in Germany. Wow, 35000 years is really old. The size of the statuette is pretty small, 6 centimeters tall and 3.4 centimeters wide. The statuette, made of mammoth ivory, shows enlarged breast and vulva. Although the definition of porn is a little bit subjective, maybe rather sensitive to your imagination, this one is not so controversial. They probably used it as some sort of decoration.

## Planck has lifted offMay 14, 2009

Posted by keithkchan in fun stuffs.

I am still alive. Of course I am not going to shut up forever. I think it is time for me to start bullshitting again.

Finally Planck has successfully launched. (Together with another satellite Herschel, I have no idea what it is, and probably nobody cares what it is.)

As you know Planck is the next generation CMB experiment, conducted by ESO. Now WMAP measures CMB temperature up to $l \sim 1000$ or so, and E-polarization is about a few hundred or so; Planck is expected to take us further afield, maybe temperature maybe $l \sim 2500$ and E-polarization to about 1500. It may also measure B-mode polarization, which can be due to the gravitational waves from inflation. The WMAP data seems to suggest that the amount of non-gaussianity is larger than simple inflation model, hopefully Planck will be able to give us a more definite answer. And many other possibilities. Maybe it will confirm string theory, but I don’t know know. Then Lubos Motl will be very happy. (Of course I will also be happy about that.)

## Meat-for-sex theoryApril 13, 2009

Posted by keithkchan in fun stuffs.
1 comment so far

The frequent visitors of the Blackboard, if they exist at all, may notice that I haven’t actively updated this blog for some time. Well, life is complicated, I have been suffering from depression for some time for various reasons. Now I try to get over from it. One of the things I may want to do is to keep this blog afresh again.

OK. There is one news in Science, entitled chimps trade meat for chance of sex; I find very interesting. In particular, it may shed light on how to get lucky for us. Researchers have found that male chimps sometimes share meat that they hunt with female chimps. I am not sure if they do it just for fun or for pure comradeship. I think they have ultimate motive. Anyway, this in turn increases the chance that the male can have sex with females by a factor of two. This effect is also long term, a few months later, the females still remember it, and this still holds. That’s pretty good deal. People who are still in the category of losers may learn something useful from it. Get luck.

## Some Foolish StuffsApril 1, 2009

Posted by keithkchan in fun stuffs.
1 comment so far

Today I saw some foolish stuffs. Thanks to my colleagues, I realize that today is April Fools’ Day. Since I haven’t updated this blog for some time, I would like to share them here.

First, I saw a piece of news of Miss Universe in BBC’s web site. The title is Guantanamo ‘fun’ – Miss Universe. It was about a visit of the Miss Universe to Guantanamo Bay. They then wrote on the blog that it was so “soooo beautiful” that they did not want to go. Oh come on that was a prison, hundred of prisoners were suffering there. Do they have any sense? I have long suspected that many of the Miss Whatever does not have a brain. It seems to confirm my conjecture. Not surprising, other viewers are also pissed off by their stupid remarks, e.g. one said “”My God! Never underestimate the predictability of stupidity. This is horrendous.” (BTW, fortunately, although I often say stupid things here, nobody so far come and kick my S =) ). Unfortunately, the Miss Universe did it a few days before Fools’ day. No excuse.

Another  fun/stupid news is about a paper posted on the arXiv today 0903.5377 (Thanks to my colleague Mr Ben for drawing my attention to this horrendous paper).  They claim that they have found that some rare clusters, whose morphology was so weired that they look like letters, and they go on to claim that it was signals from extraterrestrial civilizations. Their interpretation is no different from that people think they see elephants, monkeys, bananas, human face in the clouds. Their interpretations also reveal they have no sense of how laws of physics limit what living organisms can do (Of course they are astronomers, I should not blame them for not knowing physics).  Later my colleagues remind me that today is stupid people’s day. They are free to do whatever they think that are right. Fine. They can do whatever they like today. But I do expect that they should put version 2 on the arXiv to replace the stupid version tomorrow.

That’s the end of my April Fools’ stuff.

## An impressive mechanical dogMarch 28, 2009

Posted by keithkchan in fun stuffs.

Well I just saw a video in Dmitry Poldolsky’s blog, I find it truely impressive. I used to think that robot move in a very rigid way. But this video may changed my view point. Notice that when the robot was kicked, it tried to maintain balance by some complicated maneuvers. The robot is more vigil than some people! Truely impressive, isn’t it? Sometimes engineers can do something that impress physicists.

## Colorful Tropical FishMarch 15, 2009

Posted by keithkchan in fun stuffs, Trivia.
1 comment so far

Today, to celebrate the start of the spring break, I went to the New York Aquarium. It was pretty fun, we saw a lot of bizarre fish and water animals. In particular, it was a very good place for the whole-family-activity.

But then a natural question arises. Why are the fish so colorful? Since those tropical fish are usually small, they can be easily be spotted by their predators if they are colorful. Well, my first guess is that they live in the deep water, given the weak light, any color doesn’t matter. However, this is not true since tropical fish typically lives in the shallow water. Another explanation I come up with is that the water is not so colorless. There are many kinds of plants with colors, like corals, sea weeds, anemones and so on. So the fish, in particular the small ones, can hide in between the objects to escape from the predators. So their colorful appearances give them the chameleon effect.

My colleague thinks that we have to explain why there are so many colors. I think this is not the right question to ask. This is the question of naturalness. If we see many different colors, this is natural. While if there is only one color, we need to ask why there is only one.

But there is one thing I don’t understand. All the fish we see have the “aspect ratio” , which is the height of the body to the width, much larger than 1. Why not the other way around? That is why we don’t see fish that have aspect ratio much smaller than 1. Is it an accident or have an origin from hydrodynamics?

Update: In fact, stingrays are the type of fish with aspect much less than 1. I think the drawback of this kind of aspect ratio is the placement of eyes. They have to be placed on one side, so the fish can only see half of the world.