Sunday, June 10, 2007

Moving the blog

After spending much time in the blagosphere, I've realised that wordpress is a much better platform than blogger.com. It's easier to use, I like it's interface, lot's of nice themes and it's got built in LaTeX support. So, i've moved all the posts and comments there.

You can find the "new" blog at

http://parseval.wordpress.com

Saturday, June 09, 2007

Fishy Medicine

It's time again for the annual "miracle fish cure". You've all probably heard of the amazing fish "medicine" that the Bathini Goud family offers to people who suffer from Asthma. This year's event has recently started in Hyderabad1.


Asthmatics gather in Hyderabad for "miracle cure"

Thousands of asthmatics have lined up in Hyderabad to take the ''fish medicine'' that the Bathini Goud family has been administering since 1845.

It's a purported miracle cure, where patients swallow a live fish whole, to be cured of asthma.
...


One memember of the family which gives the "medicine", claims (emphasis mine)


Cheating means to cheat someone. Here the crowds have come themselves, ask them if they are being charged without getting cured. That would be cheating. These people do not even know what cheating is,''


That's the pity. But, I think he should know. Raising hopes with a false claim, whose efficacy has never been verified in any test, and potentially endangering the lives of asthmatics who move away from conventional (yet exteremly effective) inhalers and corticosteroids, is very much cheating.

It saddens me somewhat, that such rubbish is still being practised freely. How hard would it be to conduct a double blind experiment to see if the drug really works? And if it works, to analyze the ingredients and try understanding the chemical basis for it's efficacy, and improving it? Why doesn't any one in our government intervene to put an end to this nonsense2?

I long for the day when the majority of our society wakes up from a demon haunted world. IMO, public awarness of science can play a large role and serve as a candle in our dark, superstitous society.

Notes

[1] - Asthmatics gather in Hyderabad for "miracle cure"

[2] - Purely rhetorical. The answer, obviously, is votes.

Friday, June 01, 2007

Creation Museum

Imagine that you're visiting a museum for the first time on a bright sunny afternoon, perhaps with your family or kids. You say to yourself "Hey, this is going to be a great experience. It'll be wonderful to look at fossils, learn about the history of the earth, the time scale involved and about evolution".

But then, when you enter the museum, you notice something peculiar. A T-rex grazing in a meadow with human children playing around it? Museum guides calmly explaining that the Earth is 6000 years old? A Triceratops wearing a saddle? What's going on?

Well, It sure ain't Kansas anymore. Belive it or not, these are scenes from the recently opened, 27 million dollar, Creation Museum in Kentucky.

The Creation Museum proudly claims to present a "walk through history", and bring the pages of the Bible to life. In fact, the co-founder of the museum claims that "It's a great place for children who are in public school and haven't really decided what to believe yet". Really? Take a look at a photographic tour of the exhibits for yourself.

What's more astonishing is that museum opened to a full crowd, with more than 4000 visitors in the first day. A related survey conducted by the Princeton Survey Research Associates International, showed that 48% of Americans polled believed that "God created humans pretty much in the present form at one time within the last 10,000 years or so" 1.

The first time I read this, all I could think was

HUH?? IS THIS FOR REAL?

Passing of lies to young children as science is beyond shameful, it's criminal.

Although I'm sorely tempted to rant further about this atrocity, I'll simply end with the Wizard's First Rule


People are stupid; given proper motivation, almost anyone will believe almost anything. Because people are stupid, they will believe a lie because they want to believe it's true, or because they are afraid it might be true. People's heads are full of knowledge, facts, and beliefs, and most of it is false, yet they think it all true. People are stupid; they can only rarely tell the difference between a lie and the truth, and yet they are confident they can, and so all are easier to fool.


Notes

[1] -NEWSWEEK Poll,March 31, 2007: Conducted by Princeton Survey Research Associates International.

Sunday, May 27, 2007

Astronomy

I had a really fun astronomy session yesterday, thanks to a monstorous 10 inch Newtonian reflector made by Celestron.

I had joined the assembly of curious astronomy enthusiasts sometime after sunset, when there was still some significant light pollution in the sky. Then, while trying to figure out the ecliptic by looking at Venus, Saturn and the Moon, I was able to see something unusual. It was a small, high speed light source which was visible as it passed the moon. After some initial confusion, we soon realised that it was an artifical communication satellite, and we had seen an Iridium flare.

Then, there was a lecture on the constellations, and some famous "landmarks" in the sky. Even now, I don't understand how people claim Leo looks like a lion, by any strech of imagination. However much I try and imagine, it ends up looking suspiciously like a mouse. Anyway, after the lecturer pointed out some more constellations which I couldn't visualize, it was finally time to play with the telescope.

The first object we looked at was Venus, which was in half phase. The planet was shimmering in greyish white and the surface was absolutely featureless, although I could make out the crescent shape. It was also scintilatting a lot, which must have been to the haze in the atmosphere.

After that, was the real treat of the night, when we pointed the telescope at Saturn. Wow! It was absolutely magnificent! It's like a precious stone painted in a canvas of black. The rings are entirely visible and wonderful in color. You can even see the bands on the "surface" of the gas giant. And right next to Saturn is the dot that's Cassini. Viewing Saturn through the telescope was the highlight of the night.

Next on the list was a very bright Jupiter. We had to wait a bit for the planet to rise from the horizon, but boy was it worth it! The view through the telescope was fantastic. Jupiter is visible as a giant squashed circular disc, and surrounding are 4 satellites (Io, Europa, Callisto, and Ganymede). Although the red spot was on the other side of the planet, the reddish cloud belts were clear to see.

Having completed this mini tour of the planets, we tried to see whatever deep sky objects that were visible over the city light. With the help of the more experienced enthusiasts in our group, we were able to focus on the M13 globular cluster. I found this a slight dissapointment, becuase I couldn't make out much except an extremely fuzzy ball that was barely visible.

We also had a peek at the Beehive cluster (M44) and the optical binaries Mizar and Alcor in the Big Dipper (Ursa Major)

Finally, (on my insistence :p), we were able to point the telescope at the moon. I was dazzled by the brightness of the moon. We could see various craters near the terminator, and could even make out individual craters.

All in all, that was one of the most enjoyable evenings I've had.

Friday, May 11, 2007

Hubble's successor


Nasa unveils Hubble's successor

The US space agency Nasa has unveiled a model of a space telescope that scientists say will be able to see to the farthest reaches of the Universe.

The James Webb Space Telescope (JWST) is intended to replace the ageing Hubble telescope.

Officials said the JWST - named after a former Nasa administrator - was on course for launch in June 2013.

The full-scale model is being displayed outside the Smithsonian National Air and Space Museum in the US capital, Washington DC.
...



Yaay! I can't wait for Nasa to launch this. It's our window into the past, into the birth of our universe.

One of my friends pointed out that it costs as much as the age of the earth in years. Nice coincidence for something cosmic

Thursday, May 03, 2007

The Wikipedia debate

By now, everyone would have used the free online encyclopedia that anyone can edit, Wikipedia. It's is a portmanteau of wiki and encyclopedia. As you might have already known, "Wiki" comes from a Hawaiian word for quick, and an encyclopedia is where you get "reliable" information. By using Wikipedia, it is claimed that one can find information on practically anything. Also notice that a google search on any topic tends to throw up a Wikipedia page in it's first three links.

What does this Google-Wikipedia synergy actually lead to? It means that, whenever you need to find information about something, and you Google for it1, there's a high probably that you end up on a Wikipedia page. So, the next logical question is, how does it matter? If Wikipedia is an encyclopedia, then it should be a good place to find information, shouldn't it?

This is where some people think there's a problem. By letting anyone edit, there's a fundamental flaw in Wikipedia, and it's the problem of credibility. This flaw is especially true in science related articles. The fact that anyone can edit Wikipedia, means that someone who's not an expert can easily edit and publish the article, without any peer review or scrutiny from experts. The proponents of Wikipedia argue, based on faith, that the good and accurate articles will end up surviving, and the erroneous information will be removed.

So, although Wikipedia has an impressive collection of fairly accurate articles, such Pink Floyd or Topsy, is it something you should use when you want to learn something for the first time? A number of critics, including myself, believe that Wikipedia is not the place to go if you need scientific information, because it cannot guarantee reliable, accurate or valid informaton.

From John Baez's2 website on physics 3


At any given time, the Wikipedia unquestionably boasts some very impressive articles on scientific topics. Nonetheless, its utility as an encyclopedia is fatally compromised by the existence of a surprising number of articles which appear at first glance to be sober, factual, and supported by impressive citations, but which are nonetheless a farrago of misinformation. The problem here is that only an expert may be able to spot subtle misinformation in articles on highly technical scientific topics. The point is that an "encyclopedia" which can be safely consulted only by those who are already experts on the topic at hand is not a true encyclopedia at all!

A steadily growing number of Wikipedia articles uncritically promote fringe science "theories" or scientifically suspect investment schemes, including a surprising number of devices which, if they functioned as advertised, would constitute perpetual motion machines. It is an article of wikifaith that Wikipedia articles will improve monotonically as more people contribute edits, eventually approaching a stable state of near-perfection. In particular, adherents of the faith allege that "army of watchful volunteers" will quickly spot and correct any misinformation. However, I have been tracking problem articles for almost two years, and I know that this faith is misplaced. Many of the worst physics articles have very obviously never once been edited by a genuine physicist. Even worse, I have carefully examined the edit history of hundreds of bad science-related articles in the Wikipedia, and in dozens of cases, I believe that the evidence suggests that articles which were allegedly written by a disinterested volunteer, were in fact written by someone having a direct financial stake in the claims described in the article. (This kind of deception is known as "wikishilling"; it is simply the latest variation on a technique which has long been employed by scam artists.) These observations appear to be consistent with a general trend toward increasingly sophisticated and insidious attempts by pseudonymous editors to manipulate information presented in the Wikipedia in order to pursue some hidden personal agenda.

The trouble is that Wikipedia has erected almost no barricades to guard against such abuses. Indeed, many feel that, while traditional printed encyclopedias are biased toward mainstream knowledge — and justifiably so, since mainstream knowledge is the most stable and reliable — the Wikipedia is if anything biased against mainstream scholarship.


So, how does one best use Wikipedia? The best way to use it, would be with extreme caution. You could use it as a starting point of your quest for information, and verify whatever information you get with other independent websites. However, In the case of learning science, you're probably better of sticking to your book. A textbook is a structured, credible, peer-reviewed and best source of information if you want to learn something new.

If you're interested in the debate, there are some excellent articles written by various authors you can find in the External Links section.

Notes & External Links

[1] - And let's face it, you're hardly going to search in a different way.
[2] - Yes, the irony was intentional...
[3] - Misinformation Concerning Cosmology and Relativity



Some external links
Why Wikipedia Must Jettison Its Anti-Elitism - Larry Sanger, co-founder, Wikipedia
The Faith-Based Encyclopedia
On "Digital Maoism: The Hazards of the New Online Collectivism" - Jaron Lanier.
Avoid Wikipedia, warns Wikipedia chief


Saturday, April 21, 2007

The voice of reason

Imagine that our planet is under the threat of complete annihilation, for whatever reason, by a more advanced intelligent race. If there's one person, one individual we can send to plead the case for earth's survival, that representative for earth would have to be the astronomer, Carl Sagan. I'll never forget the day when I first came across his work, The Demon-Haunted World 1. Sagan's passion and enthusiasm for science and humanity is truly inspiring and infectious.

Sagan has written some truly brilliant 2 popular science books. If you've not read them yet, I strongly suggest that you do. Among his more popular science books, which I've absolutely enjoyed, are Cosmos, Broca's Brain, The Dragons of Eden and Billions and Billions.

This is a video where Carl Sagan talks about the famous Pale Blue Dot photograph 3, that the Voyager 1 spacecraft took. I can't find adequate words to describe the feeling of awe, beauty and humility that Sagan conveys, so I'll let you experience it for yourself.



Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar", every "supreme leader", every saint and sinner in the history of our species lived there — on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood
spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate... Like it or not, for the moment the Earth is where we make our stand.
The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate... Like it or not, for the moment the Earth is where we make our stand.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. It is up to us. It's been said that astronomy is a humbling, and, I might add, a character-building experience. To my mind, there is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly and compassionately with one another and to preserve and cherish that pale blue dot, the only home we've ever known.


From one of the greatest humans who has ever lived.

Notes

[1] - The more perceptive of you would have noticed that the name of this blog comes from the same book (The Demon-Haunted World: Science as a Candle in the Dark). No coincidence. In fact, Sagan himself was referring to the British physician Thomas Ady, who bravely wrote a treatise against the Salem witch trials.
[2] - That's a poor adjective. I'd probably run out of superlatives if I try to express just how good they are. So, if you've not read any of his works yet, what are you waiting for?
[3] - From his essay, Reflections on a Mote of Dust.


Tuesday, April 17, 2007

Vedic "Science"

I found this wonderful article by Meera Nanda, in which she highlights how modern science is being mixed up by the Vedas. The essay, titled Postmodernism, Hindu nationalism and `Vedic science', was published in the Frontline magazine 1.

This excerpt from the article2, illustrates her argument.


One of the most ludicrous mantras of Hindutva propaganda is that there is "no conflict" between modern science and Hinduism. In reality, everything we know about the workings of nature through the methods of modern science radically disconfirms the presence of any morally significant gunas, or shakti, or any other form of consciousness in nature, as taught by the Vedic cosmology which treats nature as a manifestation of divine consciousness. Far from there being "no conflict" between science and Hinduism, a scientific understanding of nature completely and radically negates the "eternal laws" of Hindu dharma which teach an identity between spirit and matter. That is precisely why the Hindutva apologists are so keen to tame modern science by reducing it to "simply another name for the One Truth" - the "one truth" of Absolute Consciousness contained in Hinduism's own classical texts.

She further says that 2,

ALL these numerous celebrations of "Vedas as science" follow a similar intellectual strategy of finding analogies and equivalences. All invoke extremely speculative theories from modern cosmology, quantum mechanics, vitalistic theories of biology and parapsychology, and other fringe sciences. They read back these sciences into Sanskrit texts chosen at will, and their meaning decided by the whim of the interpreter, and claim that the entities and processes mentioned in Sanskrit texts are "like", "the same thing as", or "another word for" the ideas expressed in modern cosmology, quantum physics or biology. Thus there is a bit of a Brahman here and a bit of quantum mechanics there, the two treated as interchangeable; there are references to "energy", a scientific term with a definite mathematical formulation in physics, which gets to mean "consciousness"; references to Newton's laws of action and reaction are made to stand for the laws of karma and reincarnation; completely discredited "evidence" from parapsychology and "secret life of plants" are upheld as proofs of the presence of different degrees of soul in all matter; "evolution" is taught as the self-manifestation of Brahman and so on. The terms are scientific, but the content is religious. There is no regard for consistency either of scientific concepts, or of religious ideas. Both wholes are broken apart, random connections and correspondences are established and with great smugness, the two modes of knowing are declared to be equivalent, and even inter-changeable. The only driving force, the only idea that gives this whole mish-mash any coherence, is the great anxiety to preserve and protect Hinduism from a rational critique and demystification. Vedic science is motivated by cultural chauvinism, pure and simple.

I tend to agree with what she says. Her article is definitely one of the most informed essays I've read.

Notes

[1] - Volume 20 - Issue 26, December 20, 2003 - January 02, 2004

[2] - Reproduced under fair use.

Sunday, April 15, 2007

Free convection for dummies

The Nonoscience blog has a nice series of articles that serve as an introduction to the principles of free convection. You can find the posts here:

(i) Introduction to Free Convection
(ii) Mechanism of Free Convection
(iii) Free Convection and the Rayleigh Number

As for me, I'm still grappling to make sense of my heat transfer course. It's hard enough trying to get a physical grasp of all those dimensionless quantities1, and on top of that, my head's still reeling trying to figure out when to use all the empirical correlations2.


Notes

[1] - Nusselt, Rayleigh, Prandtl, Grashof, Richardson, apart from good old Reynolds and Archimidies. I could probably write a poem!

[2] - Churchill and Chu, you're exempt. But Dittus & Boelter, Sieder & Tate, Petukhov, Notter & Sleicher, I'm piping confused. And then there's Whitaker, Polhausen , ... I could go on & on

Saturday, April 14, 2007

On convergence

I recently came across something interesting while reading Mary L Boas text on Mathematical Methods.

Has it ever bothered you, why the power series of a pretty function like converges only for , even though there's nothing strange which happens at ? For example, if you take , it's easy to see that there's a singularity at . But what's the catch here? What's wrong with the power series of at ? This apparent conundrum is actually trivial when one looks at it from the complex perspective. Consider the complex function,



Since is infinite when , isn't analytic in any region containing . Now, there's a theorem that says that, since is analytic at points other than , it converges inside the circle centered at the origin and extending to the singularity at . From this, one can clearly see that when , and the corresponding power series also converges only when .


The lesson here is that looking at things from a complex perspective might give important insights in the real case.

Wednesday, April 11, 2007

Darfur Images

Darfur is burning. But we all knew that already, didn't we? After all, 300,000 dead and 2.5 million homeless (just another number? think about it) isn't enough reason for the UN to actually do something.

Atleast Google isn't evil. It's possible for you to see the extent of the destruction in Darfur in high-resolution using the Google Earth software. It's impossible to miss if you pan over Africa.

For example, in the picture below, you can see the village of Niala. The circles you see are what's left of the mud huts with straw roofs, known as gottias. (Click on the images to get a larger image)



Similarly, this is the village of Selenyi, which has been completely destroyed.



In some cases, you can even see the ashes of some huts which have been recently burnt



Google Earth also allows integrates actual photographs from various destroyed villages, videos and testimonies of some survivors. Here's an account from a 61-year-old interviewed in Goz Amer


"It was early when I heard the noise and went out to see what is happening. When I opened the door there were Janjawid pointing a gun at me. They told me to stop and they aimed at me with their guns. The Janjawid were everywhere. I saw them collecting men from all the huts, it was mainly men from 16 to 35 years of age. They took them out of the village. They took as they liked, money and belongings. They took the men by car outside of the village. I could see the car returning to bring more every ten minutes back and forth. They took the men behind the mountain. The government army was there with their guns, but they did not burn the village and they did not loot. But they were there with the Janjawid. Behind the mountains they killed them and they arrested others. On that Friday they killed 116 men. I saw the dead bodies behind the mountains. They killed my son, Isa Ibrahim Shagar, he was 23 years of age. They took everything we had. We heard them shooting people. Those who were arrested were told to go and see [name of Janjawid leader] to pay to be released. This was all still on Friday.

"Those who were arrested were tied up: arms behind their body, they had to lie face down on the earth and were beaten. They were hitting them hard until their heads were bleeding. They told us that those between the age of 16-35 could not pay only those older than 55 could pay. They asked for 500.000 Sudanese Pound for one person. Only eight people could pay.The remaining men and women and children were kept under trees outside the village and the Janjawid did not allow anybody to move. We heard women who went to collect firewood who were raped. There was a 15 year old girl, I do not know her name, she was raped by the Janjawid when she went to collect fire wood. Those who were still arrested they were told to get into the cars, because they would to take them to the police in Garsila. But they were taken behind the hills and killed. Some of us could climb the hills and see what they did.On Saturday they killed the rest of the men. This time they did not use their guns, they twisted their necks. One Janjawid stood behind the man to hold him down and others twisted the neck until it broke."

Meanwhile, Sudan's president steadfastly refuses to accept that there's any crisis, completely ignoring the blinding evidence as a conspiracy of the "west" to undermine his country's sovereignty.

They say that more than 200,000 thousand have been killed in Darfur, we affirm that this number is not true and that... the number of deaths has not reached 9,000. Any talk of a humanitarian crisis is not true


So, what exactly can we, as individuals, do to end this atrocity?

Nothing really. We can only sit and observe the worst human atrocity in recent history run its course. The organization which has the military power to end this organized mass murder and genocide, the UN (or should I say, the USA?), is happy to remain a passive observer. Governments continue to "impose sanctions", "strongly condemn", "compile evidence" and do absolutely nothing while the genocide bleeds on, people murdered, just like that. Where’s the attention from the world?

Sunday, April 08, 2007

My Vision

I'm afflicted with a rare, progressive eye disease, called Keratoconus 1. While it doesn't cause blindness, it finally results in very bad vision.

Whenever my eye condition comes up during conversation2, I have a hard time explaining exactly how my vision is affected. However, I recently came across a wonderful site3 which contains a compilation of images, some of which I've used here, designed to help communicate how and what individuals with Keratoconus see.

Currently, I'm experiencing the early stages of the disease only in the right eye, so my overall vision isn't too bad. Although, one major problem is that images appear very blurred at night4. For example, this is how the moon looks through my right eye.



Driving at night is especially a problem, because of the glare and streaking of light from the oncoming traffic.



Also, distant objects are never clear or sharp. This results in me ending up with a big headache if I don't wear my glasses or contacts for an extended period of time.



Footnotes

[1] - Believe me, you DO NOT want to wiki this.

[2] - ie, rarely. Usually, I have much more interesting things to talk about. And no, it's not the weather either. Honest!

[4] - They appear slightly blurred during the day too, if you're interested, which doubtless, you're not.

Wednesday, March 28, 2007

Banach Contraction Theorem

Today, I came across a nice theorem which, If I understood correctly, proves the existence and uniqueness of points of a self map in a metric space, such that the map of that point is itself. The formal statement goes as follows.

Let be a non-empty closed subset of a complete metric space and be a map. Let be such that . Then for each , the iterative sequence converges to a fixed point x, which is unique.

To prove this, one needs to first show that
(i) for any . This shows that as
(ii) as . That is, is a Cauchy sequence in X. One can prove this with judicious use of the triangle inequality. Further, since is a complete metric space, also converges to the same in

Using the above, one can show that , and that this is unique.

Wednesday, March 14, 2007

Happy Pi Day

Apart from being Albert Einstein's birth anniversary, today also happens to be, for obvious reasons, Pi Day! So, happy Pi Day everyone!

Thursday, March 08, 2007

Optical Illusions

These are some really neat optical illusions. Many optical illusions are beautiful, astonishing and powerful. I think they show how easy it is to fool the visual system and the brain.

Same color illusion





In the above image, look carefully at the squares marked as A and B. One appears white and the other appears black, right?

Amazingly, both the squares have the same color! Don't believe it?

To verify that the color's are the same, try cutting the two squares and place them side by side in paint or photoshop. Or, you could use the colorpicker tool to check that the colors are the same.

There's an explanation of why this illusion works at the MIT site.

Scintillating Grid Illusion





This is a famous one. You'll see the sudden appearance of black dots at the crossings. Also, if you keep your eye fixed on a particular intersection, no dots appear there.

I wasn't able to find any explanation on how this illusion actually works.

Peripheral drift illusion



Click on the image to get a larger version

The 'rotating snake' illusion is one of my favorites. The 'rotation' of the wheels occurs relative to your eye movements. It's thought that asymmetric luminance at the periphery of the vision causes this illusion.

Click on the image to get a larger version of the illusion.

Afterimage illusion





Keep concentrating on the sign at the center of the circle.

Do you see the rotating green spot?

Fraser’s Spiral





Actually, there are no spirals!
The intersecting black arcs appear to form a spiral, but they are in fact concentric circles.

Zollner_illusion





Parallel or not?

External Resources

70 Optical Illusions & Visual Phenomena by Michael Bach
Optical Illusions, Wikipedia