So how much did Barzan Ibrahim al-Tikriti weigh ?

Given how much hatred there is between Shiites and Sunnis, this could well qualify for a basic physics problem in Shiite science textbooks. Or maybe our Cartman dude from South Park will be delighted to hear a lecture on the cold science of hanging by Ms. Garrison.

It is actually quite easy to explain why Barzan was decapitated while hanging and there is no need to invoke some "divine act" theory as Basam Ridha, the spokesman for Iraqi Prime Minister Nuri al-Maliki's office did. My guess is that the hangman didn't take the Official Table of Drops seriously.

John F Burns from New York Times reports that Barzan was dropped about 8 feet (or 2.43 metres) while his hanging. (Btw, according to the drop table, in modern times, a person weighing 51 kgs is given a 8 feet long drop hanging. I find it hard to believe Barzan was only around 51 kg to be given this much drop ). That means, his velocity just before his neck snapped was about 7m/s ( = sqrt(2gh) ). The science of hanging tells us that the amount of force required to snap the neck is about 4,400 Newtons. So, its safe to assume that Barzan probably felt a force of about 5,000 N. Witnesses from the execution chamber claim that just as Barzan was falling, they heard a snap and saw the noose rope fly up "instantaneously". So , lets assume that he was decapitated very quickly and took place in about 1/10 sec. Therefore, the impulse on Barzan was about 5000/10 = 500 N-sec. This impulse is the change in momentum because of the snap. Lets assume that right after the snap, his body velocity decreased to about 1/10th of what it was before the snap, i.e., to about 0.7m/s. That means, if his mass was M, his change in momentum was about 6.3M Newton-sec. This is also equal to 500 Newton-sec. So a reasonably good and crude estimate for his body mass is about 80 kg ( even though lots of assumptions were made in the calculation ) !

In any case, I would argue that Barzan probably has the most painless execution amongst the three who were hanged recently in Iraq even though decapitation "looks" more cruel.

Isn't science cool ? Many times, it definitely is very cold. If you think this calculation is in bad taste, you probably need to face reality and think the same about lots of other stuff including the death penalty.


I did not discover Cao/Zhu and Kleiner/Lott similarities

One of my friends pointed me to some writings floating around in wikipedia, ars mathematica, optimization news, etc with my name as the "discoverer" of plagiarism in Cao/Zhu paper on Poincare conjecture. This blog is to clarify what really happened. Whoever made the original wikipedia entry probably read this blog of mine where I clearly state in the first line itself that the pdf was emailed to me by Jeremy Morgan. I really don't know if the pdf was made by Jeremy Morgan or someone else. Neither do I know who first noticed these similarities. I would like to guess it was Kleiner and Lott themselves. All I did in my blog was to post the pdf file.

In any case, Cao/Zhu have finally published an erratum in the Asian Journal of Mathematics and can be read by clicking here. If you want to read a more detailed version, click here to read the recent arxiv.org posting by the same authors. This time, they renamed their paper to "Hamilton-Perelman’s Proof of the Poincare Conjecture and the Geometrization Conjecture" and clearly state in the beginning of their introduction that the full credit of proving the Poincare conjecture goes to Hamilton and Perelman.


The Ashley Treatment

One of the best "ethics" blogs I have come across. Check out Ashley Treatment. The blog is maintained by parents of Ashley X, a girl child with static encephalopathy. Her parents decided to check her growth, i.e., her height and weight using hormonal treatment. And as expected, the e-moralists have showered them with insults and slander denouncing them as lazy cruel parents who have spayed and stunted her. Remember all the rants by these moralists during the Terri Schiavo incident ?

I read the complete Ashley blog and must admit was quite impressed with its depth and rationality rather than emotional outburst. The only place I felt her parents were becoming a bit defensive was when they state
A fundamental and universal misconception about the treatment is that it is intended to convenience the caregiver; rather, the central purpose is to improve Ashley’s quality of life.
I personally would have no problem even if the intention was to convenience the caregiver and to improve Ashley's life with an equal weightage. Regarding the debates started on this issue, here is what her parents have to say:
We want to avoid sensationalism or philosophical debates about what we did and why we did it. We’d rather care for and enjoy Ashley than get into endless debates. In our opinion, only parents with special-needs children are in a position to fully relate to this topic. Unless you are living the experience, you are speculating and you have no clue what it is like to be the bedridden child or their caregivers. Furthermore, in the case of the female aspects of the treatment, women are in a better position to relate to these aspects and the benefits for which they are intended.
A very frank and sensible position to take. If you enjoy reading stuff on bioethics etc, I strongly recommend reading the complete Ashley Treatment blog.

On a lighter note, the complete South Park episode on heaven, hell, Sony PSP and Terri Schiavo can be seen by clicking on the video below. It won't last long. So see it soon :)


Onion celebrates 6 courageful years of G. W. Bush

Nice, funny interesting collection of "The Onion" news articles on Bush. Healthy way to laugh out and start your new year. Do check out the "Bush Finds Error In Fermilab Calculations" :)