Posts Tagged ‘links’

Do The Math

April 24, 2012

In a follow-up to yesterday’s post, I want to point out a blog by astrophysicist Tom Murphy at UC San Diego (I don’t know him).

Do the Math looks at back-of-the-envelope calculations related to energy, environmentalism, and related issues. Tom produces more high-quality material than I’ve been able to absorb, but what I’ve read has consistently been insightful and, thankfully, sane. Check out his post index for some food for thought.

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Let’s Read the Internet! week 8

December 8, 2008

Wind-Powered Perpetual Motion
and
Why the Directly-Downwind Faster Than the Wind Car Works”
Mark Chu-Carroll on Good Math, Bad Math

“The only true wisdom is in knowing you know nothing.”

Socrates would have to be a fan of the scientific method. We frequently acclaim the shift towards naturalism in Western thought, as a turning point in our intellectual maturity, but that shift brought with it the less-recognized roots of an even higher goal – the eradication of hubris in the search for understanding. Naturalism, the philosophical position that empirical observation holds the final word in debates on truth, essentially kills the argument of “because I say so.” Truth comes from no one in particular, so there’s at least the faint possibility that people trying to understand the way things work will some day no longer jockey and battle to be “the one who got it right.” That’s a far-out ideal, and maybe if nobody thought they were going to be credited with brilliance, nobody would have the incentive to try to do something brilliant in the first place. But at the very least, when two naturalists have an argument, they can frequently appeal to a common, impartial, higher source – nature – as arbiter.

That’s what’s happened here on Mark Chu-Carroll’s widely-read blog. He initially, and incorrectly, believed a certain device that drives overland into the wind and faster than the wind was a fraud. After long, long debates, he changed his mind, and carefully explained the mistakes in his own reasoning and what he had learned in the process of investigating his own error. Which is pretty much awesome, because such things hardly ever occur in arguments on less savory topics, like abortion. (Oh my God, was that an eating-dead-babies joke?)

I also appreciated the sort of emergent didactic property of the hundred-some post comment thread on Chu-Carroll’s original post. After watching the youtube video of the device (linked from the original post), I wasn’t completely sure whether the treadmill test was fair. It seemed reasonable enough, but I certainly wouldn’t have been prepared to defend it against someone eager to argue the opposite way.

As I read the thread, commenters raised most of the points I was considering. Other people answered those points, and then even more people chimed in with takes that I hadn’t considered at all. The overall effect was for a large amount of white noise and repetition, but also for a strikingly-diverse set of mindsets converging on the same problem. By the time I was done reading what everyone had to say, I felt that I had appreciated more intricacies in the problem than I would ever have discovered thinking about it alone, and I probably understood it better than I would have even if a single skilled author had written a long exposition. The challenge of interpreting each new voice’s arguments, incorporating them with the previous knowledge, and then parsing all of it for myself over and over, trying to find holes in everyone’s logic and patch together a firm understanding piece by piece, was absorbing because it’s so much more interactive than simply reading one single person’s explanation, no matter how clear, detailed, or precise.

It makes me want to argue about physics more often, but only in the good way where your ego doesn’t get too involved.

A Russian Teacher In America
Andre Toom, linked from God Plays Dice

A long essay that’s a borderline sob story about the woes of the American educational system. As a private tutor, I see exactly the sort of problems Toom is discussing on a daily basis – students, even (or perhaps especially) the “good” students, are so maniacally focused on their grade that learning becomes completely lost amidst a sea of test-cramming, and question-memorizing. Students are so wrapped up in the concrete performance markers visible to the world, that they don’t care at all for their true progress, visible chiefly to themselves.

That, at least, is the picture. I only partially buy it. It’s true, to varying degrees, for many students. But it’s not as if this entire nation has no one left interested in math. The sad part is that over two hundred or so students I’ve had, there have been a handful who are truly interested in math and physics, but they seldom have much guidance. Because these kids can gets A’s in math class, no one in public school is very concerned with pushing their limits when there are too many problem kids to worry about first. So I’m more interested in people with plans on how to reach interested young students with extra-curricular math opportunities than I am with people deriding a broken system.

Not everyone is going to love math. In fact, I doubt there’s ever been a society where a majority of people are interested. But the vast majority of our society has to take it in school. So yeah, it’s inevitable that there are lots of people taking math who don’t care about math. But I’ve done the same thing in a literature class before. Ultimately, math is cool enough that some people are going to discover it no matter what the educational system is like, so I’m not all that worried about the alarm bells being rung here.

Blow to Vitamins as Antidote to Ageing
James Randerson at The Guardian

We thought we understood, like, everything. Turns out not. But the next study that comes out will surely reveal the secrets to perfect health once and for all…

Swiss Approve Heroin Scheme but Vote Down Marijuana Law

Sounds like a pretty good plan to me. Administer heroin to addicts in a safe, controlled environment, thereby reducing health risks and driving down the general nastiness associated with black market activity. I can also understand why you wouldn’t want to legalize marijuana in just one small portion of Europe, since everyone would then go there just to smoke. The same argument doesn’t hold as much water for the US with its block-like geography, but I live in California, where marijuana is as good as legal anyway.

Nebulous
Tara Donovan

from Three Quarks Daily

The Not-So-Presidential Debate

The Not So Presidential Debate from aaron sedlak on Vimeo.
also from Three Quarks Daily

Why Punishment Is Worth It In The End
Ed Yong at Not Exactly Rocket Science

Read this article or else! Nah, honestly I would never be able to go through life as someone who tried to understand human interactions by designing toy experiments like this. But It’s nice to get little sixty-second summaries of their months of hard labor.

Over-budget Mars rover mission delayed until 2011
Rachel Courtland at New Scientist

Bad news, since I work at the place where they’re building this thing, and they owe me two months’ back pay already.

15 of the World’s Most Creative Papercraft Artists

You get to feeling a little bit sleazy when you realize all the exposure you’ve had to art in the last two years has come in the form of internet lists with titles like “The Top Ten Totally Badass Avant-Garde Experimental Playdoh Exhibitions of 2008!!” But on the other hand, some of this stuff actually is pretty badass, for being a paper sculpture of a cat.

A Happy/Unhappy New Pair of Studies
Stephen Black at Improbable Research

Among the headlines of news feeds I scanned through this week, there must have been at least ten stories referencing a recent paper purporting to show that happiness is “contagious”, that is, if I were to reach down and magically make your friends happy, you would become happy as well. When I first heard about this, I was intrigued, because I was wondering how you would establish this is a “contagious” effect, and not just correlation. It turns out: you don’t. The researchers, from what I can tell, simply found a correlation and announced that happiness is contagious. News stories are apparently contagious, too, because once word of this paper got out, most of the major science news outlets published something on the story.

But as the link describes, another study found that height was also “contagious”. That is, if your friends are tall, it’s likely you’re tall, too. Just as with happiness.

Sine of an Inscribed Angle
Brent Yorgey on The Math Less Traveled

A cute visualization of the law of sines.

Let’s Read the Internet! Week 7

November 30, 2008

Most Planets May Be Seeded With LIfe
Phil Berardelli Science

The title of this article really is “Most Planets May Be Seeded With Life”. I would point out what a ludicrous construction this is, but it would be approximately equivalent to nudging the guy standing next to you at the Taj Mahal and saying, “pretty nice, huh?”. The author also drops the journalistic gem, “The new find, described this week in the journal Astro-ph, is stronger.” Which is a bit surprising, because “Astro-ph” is not a journal at all, but just the name of the astrophysics section of arXiv.org, where physicists post free preprints of their work. The paper, which can be found here, has actually been accepted for publication in The Astrophysical Journal Letters.

The paper uses the word “life” twice in seven pages of text – once in the abstract and once in the introduction. The news story uses the word “life” five times, including in the title. I made a token attempt to skim through the paper, but I have no experience with astrochemistry and can’t really say much about the scientific merit of the work. The data sure looks pretty.

Here is the bottom line: the researchers behind this paper work hard at solving technical problems. The problem they were trying to solve here is, “how can you tell whether some particular organic molecule is out there in a given direction of outer space, when you can’t go there, can’t send a probe, can’t do an experiment, and can only passively collect a little bit of light?” Their work is astrochemistry, and it has no honest direct association with the origin of life. Also, if you want to understand what they do, you will have to devote a lot of time and energy into it.

But, the science writer is on a deadline. I know someone who interned for Science and wrote this sort of five-minute story. You probably only have one day to read about the work, get in contact with and get a quote from one of the lead scientists on the paper, then find another, independent scientist in the same field, who has also seen this particular preprint on the arXiv, and get a quote from that guy to balance the story out. Then you have to throw your story together as quickly as possible so it can go through revisions and the art people can find a relevant graphic, so you add a pun if you can detect one, and somehow make it catchy or attention-grabbing with the least possible effort. Of course “Origin of Life!” becomes the slant of the story.

I see two problems with this. One is that there are a lot more “origin of life” stories out there than there are actual breakthroughs on the origin of life. So if you’re innocently following at home what “those guys in the white labcoats” do all day, you’d at first think they’re making huge progress every week. Then after a while, you’d begin to wonder why, if they’ve been making so much huge progress, they still don’t seem to have all this figured out yet.

The second is a problem I’ve personally encountered. Science simply is not 100% adrenaline. Most of it is boring. Scientists spend much of their time waiting for gels to run, debugging their code, and fixing their lasers. (Sound awesome? It gets monotonous. But there are those few seconds every once in a while where you think, “Whoa! I play with lasers all day!” Then your thesis adviser tells you how much he’s looking forward to your presentation in group meeting on Monday. This is Friday night. You start to cry.) Having a science job is a lot like having a normal job. You just work more and get paid less.

That isn’t the picture you get coming in, though. Many of my high school students (I’ve had a couple hundred) have told me that they “love” science. I cringe a little when I hear that. (I cringe a lot when I get, “I love science, but I just don’t get the math part of it.”) Loving science, for them, just isn’t possible. They don’t know science. They might love the ideas they learned in science class. They might have loved doing their science fair project. But they probably will not love writing grant proposals or reviewing inscrutable papers. When they do finally get to the lab, they get a little confused about what it is they were looking forward to all this time. Come to think of it, maybe I was using the wrong pronoun this last paragraph, and wasn’t referring to my students at all.

Of course, seeing problems is easy. Everyone sees a thousand problems a day, mostly with other people. Then they bitch about it a bit and consider the issue closed. Not that I see a solution. But let’s leave the issue open.

Sea Change For Turtle Origins
Erik Stokstad at Science

I like this one much more than the last. Its attempt at a pun is so bad it’s simply confusing. It gives a nice picture of the “we don’t know shit” side of science. The underside of a turtle shell is apparently called a “plastron”, which is an egregiously-awesome term for such a mundane thing. Finally, there is a guy saying “The reason I’m excited about that is that it pushes the story of turtle origins even further back in time.”

Well shit yeah, baby! Now I’m excited, too. I’m so wired I can barerly acontrl my ffingers on the keybaorad.

Happy Thanksgiving
Nikita at Monosyllables

Here’s an awful confession. I was sitting around with some other guys like myself (well, not EXACTLY like myself, but other young American nerds) on Thanksgiving, projecting the computer screen on the wall so we could watch downloaded versions of Arrested Development. A story from Google news popped up citing the number of people killed that day in the terrorist attacks in Mumbai. I jokingly calculated that because Mumbai has about 13 million people in it, and people live 70 years or so, we could calculate the daily death rate there, which is order of magnitude 500. That gives a daily standard deviation of root 500, or 20-25 people assuming deaths are independent, randomly occurring events. The attacks that day were a three or four-sigma event. Barely statistically significant, because that many extra people should die totally at random in Mumbai once every few years. Then Nikita’s post reminded me there were real people there, that I knew some of them, and that it wasn’t so great a joke.

The Toughest Man In Cairo Vs. The Zionist Vegetable
Anand Balakrishnan in Bidoun

According to my old neighbor, Kamal Hanafi, the vegetables in Israel are huge and good for only one thing. “The cucumbers,” he exclaimed, eyes lighting up, “are this long”—he stretched his hands more than a foot apart. “They are this wide”—he made a circle with his two hands. “And they taste like shit, all chemicals and unnatural fertilizers.” He spat. “No one can eat vegetables that disgusting. The only people who use them are the women, who sit like this”—he spread his legs to demonstrate. “And the men, of course.” The invisible cucumber in his hands jabbed sharply up. “And now they’re sending their vegetables to Egypt to fuck us all.”

Dancing Droplets and Spherical Harmonics
Stefan on Backreaction

Little bubbles of oil resonating as spherical harmonics. I’ll bet you didn’t know they could do that. Now you do.

Perfect athlete’s 100m sprint time calculated
Dave Robson on New Scientist

More terrible abuse of the word “science”. The article says, “fitting the data to a mathematical model that matches the other results, Denny predicts future male sprinters will at best shave 0.21 seconds off Usain Bolt’s current world record of 9.69 seconds for the 100 metres.”

It’s wrong. It’s so terribly wrong. There is really no reason to believe that just because you drew a curve through some data points, you’ve predicted the future. If it were that easy, everyone would have done it earlier, and predicted today’s world records. But they didn’t. The article itself does technically refrain from calling the work “science”. But apparently it’s actually being published in the Journal of Experimental Biology, despite containing no experiment or biology. Can’t we just take all these people and send them somewhere?

Beethoven and Borge
from In The Dark

Humor on the piano. It’s like stand up comedy, but they’re sitting down. You better be, too, before watching these wacky films!

That’s it for this week. I read plenty of other stuff, but it was just boring things. Reminded me of you.

Let’s Read the Internet! week 6

November 24, 2008

Becoming Screen Literate
Kevin Kelly in The New York Times

I am not screen-literate. My first reaction to this article was to think the barrier to becoming screen-literate was still rather high – there’s a learning curve associated with using the video technology Kelly is writing about. Not all that many people are skilled at video editing, but nearly everyone can write. But then I realized that not that many people put much effort into becoming “screen literate”, whereas everyone in America is forced to write extensively in school for many years.

So what are the consequences of “visualcy” dominating over literacy? Is it a Brave-New-World-esque degeneration into overstimulation, short attention spans, and a intellectual hedonism, or a improvement in the efficiency with which we can absorb, process, and create new information that leads to higher levels of creativity, collaboration, productivity, and better life?

The Plan
Jack Handey in The New Yorker

Garrett Lisi’s Exceptional Approach to Everything
Greg Boustead in Seed

They forgot to draw his hair. Also, this story would be more inspiring if Lisi’s work were broadly considered by other physicists to be a meaningful step forward in theoretical physics. His work has gotten far more media attention than attention from his colleagues.

Chicks Dig Scars
Finally, a good reason to cut yourself.

Cool Things the Greeks Did in Astronomy
Dot Physics

How are you supposed to measure the distance to the Sun? Turns out it’s more than a million hot dogs end to end. Of course, hot dogs shrink a little as you cook them by putting them closer to the sun, but still, it’s a lot. How did they count that high anyway?

Let’s Read the Internet! Week 2

October 19, 2008

Davisson-Germer Experiment Chad Orzel at Uncertain Principles
The first observation of the wave properties of electrons came by accident. Just like you.

A Beautiful New Theory of Everything Garrett Lisi on TED.com
In case you were wondering how everything works…

Didn’t quite catch that? Don’t worry. You can always read the paper.

Infinity is NOT a Number Mark Chu-Carroll at Good Math, Bad Math
More comprehensible than the previous post, if less profound. The fundamental problem with making infinity a number seems to be that it lets you prove all manner of foolishness, such as 1=2.

The Universal Declaration of Human Rights

It’s awfully pretentious to claim your document to be “universal”. Who has the authority? Further, what does it mean for everyone to be equal in rights? Clearly, we are not equal in many senses. Separating out “these things are rights” and “these things are what you have to deal with because of the circumstances of your life” is a tough task. For example, according to this declaration, everyone has a right to marry. But marriage is simply not a universal concept among humans. It’s perfectly conceivable to have viable, righteous societies with absolutely no concept of marriage. The concepts of privacy and property ownership could be sacrificed in righteous societies, under the right circumstances. Creating a list of rights that’s simultaneously universal and specific seems nearly impossible. But the visualization is nice.

Dead Waters Romain Vasseur et. al
Boats that get stuck in plain water. I don’t understand why this works, but the video is really cool.

Chimpanzees Make Spears to Hunt Bushbabies Not Exactly Rocket Science
Like it says, chimps make weapons and kill shit with them. In case you were wondering where we get it from.

Late Bloomers Malcolm Gladwell in The New Yorker
Just because you’re old doesn’t mean you’re useless. Therefore, you might as well slack off for another year or two before beginning that “great life’s work” stuff.

Where’s the Algebra? Michael Alison Chandler on X = Why?
Some chick with a seriously ugly smile asks whether algebra is important. But her “education” from her brother sadly misses the point. She asks, “what good are equations?”, and he replies “We have to learn equations to install lights.” But the entire article is written with the attitude that these equations are magical things that pop out of nowhere to describe lighting systems, their goal being to confuse blue-collar workers to the greatest extent possible. I don’t think there’s any understanding here the equations actually come from somewhere. Someone used a more basic set of principles to derive the equations, or else conducted experiments and then found equations to describe the results. Applying equations to describe real situations is not supposed to be a matter of plugging numbers into formulas.

The Cartoon-Off Farley Katz at The Cartoon Lounge
Normally, I wouldn’t bother linking to something that’s already been Slashdotted, but I bookmarked this page for “Let’s Read the Internet on Wednesday, and then the Slashdot post comes up just hours before I compile my links for the week. I guess the fact that the entire geek culture already knows about doesn’t really impact how funny it is.

The Sun
The web page that makes you go blind if you stare directly at it.

Fabry, Perot, and Their Wonderful Interferometer Skulls In The Stars
The author consistently produces wonderful posts explaining concepts in optics from a historical point of view. I actually used a Fabry-Perot interferometer in physics lab once. What I learned there is that they make surprisingly bad hammers.

Let’s Read The Internet! Week 1

October 12, 2008

Earth From Above

Sensory overload.  Thirty photographs of socially-relevant scenes from around the world, each of which could easily launch me on a few hours of reading and comparing.  Taken together, they present an overwhelming mosaic of a vibrant, living, interconnected, diverse, and changing planet.

But, damn, I just noticed that the story has gone from displaying 30 photographs to just ten, and the impact is nowhere near as great.  It seems hypocritical that the coordinator of the exhibit (not the artist) should ask the website to take photographs down, when the whole point of the exhibit, as expressed by the artist, is that it be completely free and displayed out on the streets in cities across the world to reach as broad and diverse an audience as possible.

Not the end of evolution again!

  John Wilkins at “Evolving Thoughts”

You might have heard about some guy telling the media that human evolution is over because we now care for our sick.  Wilkins presents a brief, irate counterargument.

I’ve done some reading on evolution from time to time.  What I’ve learned is that’s it’s deceptively difficult to understand.  Although the basic idea that heritable variation and selection pressure combined lead to evolution is straightforward, there are an awful lot of intricacies you find when you begin to look more closely.

There are some things you can do – such as study genomes to see how closely-related two species are, or study fossil records to document the evolutionary history of a species.  But there are a lot of things you can’t do, such as say, “Dinosaurs evolved to be really big because they were in an arms race.  Prey got bigger, so predators were forced to get bigger, and then prey got bigger again and off they went.”  That is not a falsifiable hypothesis, because you can’t go back and test it.

You can study evolution mathematically, and you can make falsifiable predictions, and then compare those predictions to observation.  But statements like, “human evolution is over because we care for our sick” are basically pseudoscience.

Extremely simplistic thinking about evolution leads to paradoxes.  For example, now that we first-world men don’t have to worry much about dying in our mothers’ arms during infancy, getting killed in battle at age 16, or starving to death when the buffalo find a new migration route at age 27, shouldn’t the biggest factor left in our reproductive success be how good we are at attracting women?  And therefore, shouldn’t every man spend all his effort spreading his seed far and wide?  Shouldn’t guys just be thinking about sex all the time…  Oh, never mind.

How We Evolve

Benjamin Phelan at Seed Magazine

A lengthy article about the sort of thing I referenced above – collecting data from genomes to study evolution.  Here, the scientists took genomes from humans of varying ethnic background and looked for characteristic differences in their DNA as evidence of evolution.  Bottom line: Yes, people are still evolving.  For example, as a white man, I am a highly-evolved lactase-producing being, unlike the those primitve, dairy-bloated Asians.

In Defense of Difference

Maywa Montenegro and Terry Glavin at Seed Magazine

In a companion article to the one above, the authors discuss why we might want to save the rainforest, anyway (because we like rain?).  Not just because we like toucans or want to display a World Wildlife Fund bumper sticker on our Prius.  Because it has economic, social, medical, and scientific value to humans.

The idea is that biology is a huge information-gathering system.  From a protein to an organism to an ecosystem, evolution allows biology to record information about how to live in the world, and also provides a ready-made task force 10^30 cells strong that will do its best to find out how to live in a changing world.  The more stuff we destroy, the more Earth loses the ability to adapt to hard times.  Clear the rainforest to raise crops, and disease or natural disaster or pollution find it much easier to brutally rape the new, homogenized biosphere.

The argument is then extended to such things as preserving human languages, which record the results of thousands of experiments in creating human culture.  So nature is basically a billion billion whatever tiny lab books full of experiments, and instead of reading them, we’re throwing them out.

Nobel Sur-prize

Peter Coles at “In The Dark”

Particles are everywhere.  While you read this, particles are in your home, in your infant child’s crib.  In her anus.

I don’t understand them.  But here’s a fairly simple explanation of the work that won this year’s Nobel Prize in physics.  Basically, the uproar is that this guy Cabibbo had a big idea about physics that helped explain a mystery about particles.  Later, Kobayashi and Maskawa solved a mathematical problem that expanded on Cabibbo’s idea.  Both were important – the original idea and the difficult mathematical extension to it – but only one was awarded the prize.

Also check out a more basic article from Mark Chu-Carroll at “Good Math, Bad Math”

What positive psychology can help you become

Martin Seligman on TED

A talk interesting enough that I watched it twice.  The second time while smiling. Seligman decided to break happiness, or life satisfaction, into three categories.  (To me this is rather arbitrary.  It’s not like the categories of happiness are just sitting out there, waiting to be discovered.  But it’s a persistent plague among people who study such things to break them down into categories they believe are fundamental. i.e. “four personality types”, “two political ideologies” (left/right), or even “four kingdoms of life” (some people now say up to 13.  others 2))

The categories are: surface pleasures like active social life, good love life, and sensual pleasure; “flow”, or the state of intense focus and concentration associated with, say, rock climbing or physics sets; and “meaning”, or finding something greater than yourself to dedicate your life to.

Seligman describes the beginnings of a movement to apply a scientific approach to the study of happiness, as opposed to the traditional psychological model of simply curing mental illness and depression.  He claims that it is possible for people to increase the fulfillment they feel in life by a concentrated effort in the right direction.  It’s a summary of the beginning of a quest to understand people in a new way, and apply that understanding to make life better.

Worldmapper

A site you may have seen before.  They use maps of the world to visualize data.  For example, compare a map where each country’s size represents the number of personal computers in that country, to a map showing how many people died of “often preventable deaths”.

There are a lot of technically-interesting things about this project.  How did they get the countries to fit together, when their land area needs to be fixed at some arbitrary size?  What sort of properties of the standard world map’s topology were they trying to preserve?

But more interesting are the social, economic, and political insight you can get.  Compare this project to the Gapminder.

Small samples, and the margin of error

Terry Tao at “What’s New”

Terry Tao tones it down a notch to present something even I can understand.  He discusses how a random sampling of just 1000 people can give an accurate picture of the opinions of a nation of 200,000,000 voters.  He also gives a short proof of the accuracy of the sample, without resorting to the binomial distribution.