Archive for April, 2012


Don’t worry, be happy, it’s all just a matter of scale…

As I mentioned in my last post, the interwebs are a fantastic asset to spreading information. Information, after all, wants to be free to spread itself in the wild. One of the downsides of this fantastically efficient network of ours is the spread of information that is alarmist or even false.

Consider this article that a very concerned friend sent me the other day: The Radiation Warnings You Won’t Get from the Mainstream Propaganda Machine

scary greenpeace image

Aside from the fact that it is poorly researched muckraking, with little to no sourcing of information, it is totally designed to play on our lack of scientific understanding.

Consider:

Samples of milk taken across the United States have shown radiation at levels 2000 percent higher than EPA maximums. The reason that milk is so significant is that it it representative of the entire food supply. According to an article published on Natural News, “Cows consume grass and are exposed to the same elements as food crops and water supplies. In other words, when cows’ milk starts testing positive for high levels of radioactive elements, this is indicative of radioactive contamination of the entire food supply.”

Follow the article to Natural News and they begin reporting things like “Fukushima radiation taints US milk supplies at levels 2000 percent higher than EPA maximums” They source their data, which is a good thing. The first problem is more that the data is now over a year old. The second problem is that most people don’t really understand radiation contamination levels in any meaningful way.

Ask yourself, do you know what pCi/L means? More than likely you had no idea it stands for picocuries per liter. Even if you did happen to know that definition, which I will confess I did not remember it from my last Physics class at Berkeley more than 20 years ago, you almost positively had no idea that it stands for one trillionth of a curie.

The basis for the curie is the radioactivity of one gram of radium. Radium decays at a rate of about 2.2 trillion disintegrations (2.2×1012) per minute. A picocurie is one trillionth of a curie. Thus, a picocurie (abbreviated as pCi) represents 2.2 disintegrations per minute. To put the relative size of one trillionth into perspective, consider that if the Earth were reduced to one trillionth of its diameter, the “picoEarth” would be smaller in diameter than a speck of dust. In fact, it would be six times smaller than the thickness of a human hair.

Now the interesting thing about stating the risk in terms of picocuries is that you cannot convert that to sieverts. This is because pCi (picocuries) and Sv (sieverts) are not compatible. We use sieverts to quantitatively evaluate the biological effects of ionizing radiation as opposed to just the absorbed dose of radiation energy, which is measured in grays.

unit dimensions common physical quantity
pCi (picocuries) 1/[time] radioactivity
Sv (sieverts) [length]^2/[time]^2 equivalent dose of ionizing radiation

The reason you cannot compare the two has to do with the time component to sieverts that is used to establish the risk of harm from exposure to radiation. By comparison, picocuries only tell us an amount of radiation at period time-1 and cannot tell us anything about the biological impact of exposure over time.

Where does this leave us? Well, at least one of the reasons why radiation is so scary for most people is that it is invisible (and of course potentially deadly). This invisible “threat” can be as terrible as the fallout from Fukushima ( 40 mili-sieverts ) or as harmless as eating a banana ( 0.1 micro-sieverts ). In fact, when I go to the dentist’s office I refuse to wear a lead vest when getting dental x-rays. This usually scares the shit out of the oral hygienists. Silly right? The average dental x-ray is 5 micro-sieverts and my flights from Boston to San Francisco ( one way ) which I make 8 to 10 times a year are exposing me to 40 micro-sieverts EACH time I fly. Perhaps I should get Virgin America to give me a lead suit to wear!

( See the wonderful chart at XKCD for a better understanding of Radiation dosages ).

The bottom line is that radiation may be invisible, but it is not magic. With an application of the right medium and an understanding of the physics involved, we can (indirectly) see radiation happening in real-time ( see cloud chamber video below ). Perhaps if we expand our understanding of radiation we will be less afraid and less susceptible to the fear mongering and muckraking of the interwebs.


Unplugging. An experiment in abject failure.

It was once said that “Connectedness has brought glut.”

Information and connectivity feed on each other. They also feed on us. And we on them.

Facebook captures the best we have to offer – our ideas, our love of one another, the epochs of our lives. Facebook also feeds our addiction and the worst of our proclivities – our obsessions, our desire to be informed of the minutia of other people’s lives, as my grandmother would have said, Lashon Hara ( לשון הרע ). Facebook was unimagined at the time James Gleick wrote the book FSTR:The Acceleration of Just About Everything but it now reads like a cautionary tale of that which has come to pass in just this last decade.

As the likes of the internet, and Facebook in particular, unravel the neat and natural compartmentalization of the periods of time in my life, I find myself slightly unnerved. I know I’m not the first person to observe this phenomenon. I’m sure I’ll not be the last.

If we look at the mathematics of the problem, we see that I am connected to upwards of 1,165 “friends.” A term which here means everyone from people I went to kindergarten and summer camp with, co-workers, kids I’ve coached, and, almost any imaginable class of person in between.

For most of human history, our experience ( the collective knowledge of humanity ) has been spread through proximity. If the early internet disabled the need for proximity to exchange reports of our experiences, Facebook has supercharged our information exchange.

Knowledge and ideas can spread voraciously with these kinds of numbers. In a group of 1,165 people, the numbers of possible iChat or email conversations works out to be a rather large number. The approximate form is 5.011 x 10^350. The exact form is calculated here:

5011237068214031931148893693477333140204405861862670258192006969009741643455
8532257207798938139010492265139820030778610929220819644445614612753298956460
5445620240162582369255859075343949954698441621936637065854337745860837989037
658841482298624409787145419505417214065636350382928000221168542070444604843
929293178742119092578424243146009944450224095232

Think of the potential feedback loops with Facebook now claiming over 800 million users. In the not to distant past, even in a place like New York City, we lived close enough and were friendly enough to only a few people to, say, read their journals or track the temperature of their hot tubs ( now blogs and tweets). Now, each of you readily feeds the stream of information ( I’m doing it now ). The Facebookification of information paths leads to positive feedback effects in the nature of frenzies. The more people talk and write about things like the death of Dick Clark or that kid singing the more people seem to want to hear.

You might remember the Standard Temperature and Pressure lecture from high school physics. If you do, then you will recall that as fluid pressure rises, molecules collide faster and more frequently. As a result, the temperature rises too. Close packing and transmission speed are two sides of the same coin. Information travels faster through dense networks, and if you are like me, you get a little addicted to the flow and speed.

It seemed every time I thought I could go a day without sending just one more note to a friend here or a friend there, no luck. My iPhone enabled me to post to Facebook and bug my friends I had left behind on the slightest whim. My iPad allowed me to compose blog posts, collaborate with a few friends via google docs on various things from work projects to fun projects. I wasn’t the only one mind you.

In a nutshell, even though I wanted to walk away and unplug, everything and everyone around me was plugged in here and there. Just one more email. Just one more text message. Just one more… The one exception was Torri who managed to avoid texting the homeland. She’s also not on Facebook. Perhaps there’s something to avoiding this network all together. Oh well, I guess I’ll have to wait for another lifetime to find out.

Thank goodness I’ll be out of range when I take my middle son Zachary to Yosemite this summer