TSA and X-Ray Scanners

I was trying to answer a biological physics question from a family member about TSA's use of X-ray scanners, when I came across a very interesting article from Scientific American:

One after another, the experts convened by the Food and Drug Administration raised questions about the machine because it violated a longstanding principle in radiation safety — that humans shouldn’t be X-rayed unless there is a medical benefit. 

... Today, the United States has begun marching millions of airline passengers through the X-ray body scanners, parting ways with countries in Europe and elsewhere that have concluded that such widespread use of even low-level radiation poses an unacceptable health risk. The government is rolling out the X-ray scanners despite having a safer alternative that the Transportation Security Administration says is also highly effective. 

That safer alternative is the millimeter-wave scanner, which uses low-frequency radio waves which do not have enough energy to damage DNA.  Radiation of X-ray frequency can damage DNA and thus, in high enough doses, cause cancer.

I told my concerned family member that as an individual person, the risk that you will get cancer from an X-ray scanner is apparently negligible:  about 1 incidence of cancer per 10 million scans, by one estimate.  The drive to the airport and the flight itself are probably more dangerous, and if you really want to minimize the risk of cancer you can forget about sunbathing on the beach once you arrive at your destination.  But from a public health standpoint, when you have a population of millions of people it becomes likely that a few of them will get cancer each year from X-ray scanners.  Why risk the health of even one traveler unless absolutely necessary?

Who was Gore Vidal?

He died last week at age 86.  I guess it was timely that I blogged about William F. Buckley, as the two were public adversaries as you can see in this clip.  Other than that, I don't know much about Gore Vidal.  Who was he?  Perhaps someone with broader experience than myself can help me out.

Conservapedia vs. Einstein

It's no surprise that a website like Conservapedia provides a megaphone for creationism and climate change denial.  What is remarkable is that this anti-science attitude extends all the way down to the seemingly apolitical laws of physics, namely Einstein's theory of relativity.  Putting aside Conservapedia's handling of the topic -- with its careful cherry-picking of facts, and quoting physicists out of context -- what on earth has relativity got to do with political ideology in the first place?

The conservative magazine The American Spectator entered the fray, too, publishing an article which questions relativity.

Conservapedia styles itself as "The Trustworthy Encyclopedia".  (It has to be trustworthy ... there's Old Glory flying triumphantly right there in the logo.)  Unlike Wikipedia, "We do not allow liberal censorship of conservative facts" over at Conservapedia.  I think that says more about the website's attitude towards facts than its authors intended.

Selfish genes, nice people

Few things are more fascinating to me than an apparent, but not actual, paradox.  For example:  I acknowledge the scientific fact that life has evolved by a process of ruthless Darwinian selection.  I am also a humanist who believes in principles that transcend narrow self-interest.  Isn't that a contradiction?

These issues are on my mind because I have finally gotten around to reading The Extended Phenotype, which is a follow-up to The Selfish Gene, Richard Dawkins' celebrated book on modern evolutionary biology.  I highly recommend both.  (But read The Selfish Gene first!)  


A common misconception is that these books advocate social Darwinism, i.e. ruthless aspiration to "survival of the fittest" in our personal and political lives.  In reality, the books merely explain the fact of biological Darwinism, i.e. the mechanism in nature by which all species, including humans, came to be.  


Hence the resolution to the apparent paradox:  the answer to the question "Where do we come from?" has already been written by nature.  The answer to the question "Where do we go from here?" is entirely up to us.  (The two answers are related, actually -- it seems evident that "selfish" evolutionary competition has written a sense of morality and even altruism into our genes, and this is another apparent [but not actual] paradox.  In any case, the two answers are not interdependent in principle.)  Like me, Richard Dawkins is a humanist who marvels at evolution, finds social Darwinism repugnant, and sees no contradiction in this.

What do you think, contradiction or nay?  How do you cope, personally, philosophically, or politically, with the fact that nature is "red in tooth and claw"?  (Vegans need not reply.)