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kottke.org posts about science

Willpower, Wealth, and the Marshmallow Test

The marshmallow test is a famous psychological experiment designed by Walter Mischel in the 1960s. Kids were given a single marshmallow but told they could have another if they refrained from eating the first one for 15 minutes. The results seemed to indicate a much greater degree of self-control amongst those children who were able to delay gratification, which led to better outcomes in their lives. From a New Yorker article about Mischel:

Once Mischel began analyzing the results, he noticed that low delayers, the children who rang the bell quickly, seemed more likely to have behavioral problems, both in school and at home. They got lower S.A.T. scores. They struggled in stressful situations, often had trouble paying attention, and found it difficult to maintain friendships. The child who could wait fifteen minutes had an S.A.T. score that was, on average, two hundred and ten points higher than that of the kid who could wait only thirty seconds.

But Mischel only tested ~90 kids from a single preschool. Researchers from UC Irvine and NYU recently redid the test with more kids that were more representative of the general population and found that household income was a big factor in explaining both the ability to delay and outcomes.

Ultimately, the new study finds limited support for the idea that being able to delay gratification leads to better outcomes. Instead, it suggests that the capacity to hold out for a second marshmallow is shaped in large part by a child’s social and economic background β€” and, in turn, that that background, not the ability to delay gratification, is what’s behind kids’ long-term success.

If you’re poor, you might look at the promise of future food somewhat dubiously…and not because of a lack of self-control:

The failed replication of the marshmallow test does more than just debunk the earlier notion; it suggests other possible explanations for why poorer kids would be less motivated to wait for that second marshmallow. For them, daily life holds fewer guarantees: There might be food in the pantry today, but there might not be tomorrow, so there is a risk that comes with waiting. And even if their parents promise to buy more of a certain food, sometimes that promise gets broken out of financial necessity.


An explainer video from 1923 about Einstein’s theory of relativity

In 1923, Inkwell Studios1 released a 20-minute animated explanation of Albert Einstein’s theory of relativity, perhaps one of the very first scientific explainer videos ever made. Films were still silent in those days and the public’s scientific understanding limited (the discovery of Pluto was 7 years in the future, and penicillin 5 years) so the film is almost excruciatingly slow by today’s standards, but if you squint hard enough, you can see the great-grandparent to YouTube channels like Kurzgesagt, Nerdwriter, TED Ed, minutephysics, and the 119,000+ videos on YouTube returned for a “einstein relativity explained” search. (via open culture)

  1. Inkwell later became Fleischer Studios, which made cartoons like Betty Boop, Popeye, and the first animated Superman series. They also introduced the bouncing ball as a technique for singing along to on-screen lyrics.↩


A brief history of fingerprints

Smudge Art

Chantel Tattoli’s piece for The Paris Review, The Surprising History (and Future) of Fingerprints, is interesting throughout, but these two things leapt from the screen (italics mine):

It is true that every print is unique to every finger, even for identical twins, who share the same genetic code. Fingerprints are formed by friction from touching the walls of our mother’s womb. Sometimes they are called “chanced impressions.” By Week 19, about four months before we are issued into the world, they are set.

WHAT?! Is this true? A cursory search shows this might indeed be the case, although it looks as though there’s not established scientific consensus around the process.

Also, Picasso was fingerprinted as a suspect in the theft of the Mona Lisa from the Louvre:

When French authorities interrogated Pablo Picasso, in 1911, at the Palais de Justice about the theft of the Mona Lisa from the Louvre that August, he was clad in his favorite red-and-white polka-dot shirt. Picasso cried. He begged forgiveness. He was in possession of two statuettes filched from the museum, but he hadn’t taken her.

“In possession of”? Turns out a pal of Picasso’s lifted the statuettes from the museum, which was notoriously easy to steal from, and sold them to the artist, who knew exactly what he was buying.

True to Pieret’s testimony, Picasso kept two stolen Iberian statues buried in a cupboard in his Paris apartment. Despite the artist’s later protestations of ignorance there could be no mistaking their origins. The bottom of each was stamped in bold: PROPERTY OF THE MUSΓ‰E DU LOUVRE.

Fingerprint art by Evan Roth. (via @claytoncubitt)


Global Warming Blankets

Using simple graphic representations of annual temperatures (like this one posted by climate scientist Ed Hawkins), people are knitting and crocheting blankets that show just how warm the Earth has gotten over the past few decades. See Katie Stumpf’s blanket, for example.

Global Warming Blankets

According to climate scientist (and crocheter) Ellie Highwood, these blankets are a subset of “temperature blankets” made to represent, for example, daily temperatures over the course of a year in a particular location. The blanket she crocheted used NOAA data of global mean temperature anomalies for a 101-year period ending 2016.

I then devised a colour scale using 15 different colours each representing a 0.1 Β°C data bin. So everything between 0 and 0.099 was in one colour for example. Making a code for these colours, the time series can be rewritten as in the table below. It is up to the creator to then choose the colours to match this scale, and indeed which years to include. I was making a baby sized blanket so chose the last 100 years, 1916-2016.

If you read her post, she provides instructions for making your own global warming blanket.

P.S. You might think that with the Earth’s atmosphere getting warmer on average, these blankets would ironically be less necessary that they would have been 50 years ago. But climate change is also responsible for more extreme winter weather events β€” think global weirding in addition to global warming. So keep those blankets handy!


Degrees of Uncertainty

Degrees of Uncertainty is an upcoming documentary by Neil Halloran that “uses data-driven animation to explore the topic of global warming”. It’s based on this XKCD comic of A Timeline of Earth’s Average Temperature.

Halloran is a creator of the excellent The Fallen of World War II interactive documentary, so I’m looking forward to seeing what he does with the topic of climate change.


Can bacteriophages rescue us from drug-resistant bacteria?

Last month when I posted a video comparing the sizes of various microorganisms, I noted the weirdness of bacteriophages, which are bacteria-killing viruses that look a bit like a 20-sided die stuck on the top of a sci-fi alien’s body.

Bacteriophages are really real and terrifying…if you happen to be a bacteria. Bacteriophages attack by attaching themselves to bacteria, piercing their outer membranes, and then pumping them full of bacteriophage DNA. The phage replicates inside of the bacteria until the bacteria bursts and little baby bacteriophages are exploded out all over the place, ready to attack their own bacteria.

I couldn’t find a good explainer (video or text) about these organisms, but over the weekend, Kurzgesagt rode to the rescue with this video. In the second part of the video, they discuss whether bacteriophages might form the basis of an effective treatment for antibiotic-resistant infections.


The Finkbeiner test for gender bias in science writing

In a 2013 piece, Christie Aschwanden suggested a test in the spirit of the Bechdel test for avoiding gender bias in profiles written about scientists who are women.

To pass the Finkbeiner test, the story cannot mention:

- The fact that she’s a woman
- Her husband’s job
- Her child care arrangements
- How she nurtures her underlings
- How she was taken aback by the competitiveness in her field
- How she’s such a role model for other women
- How she’s the “first woman to…”

Aschwanden named the test after her colleague Ann Finkbeiner, who wrote that she was going to write a piece about an astronomer without mentioning that she, the astronomer, was a woman.

Meanwhile I’m sick of writing about [gender bias in science]; I’m bored silly with it. So I’m going to cut to the chase, close my eyes, and pretend the problem is solved; we’ve made a great cultural leap forward and the whole issue is over with.

And I’m going to write the profile of an impressive astronomer and not once mention that she’s a woman. I’m not going to mention her husband’s job or her child care arrangements or how she nurtures her students or how she was taken aback by the competitiveness in her field. I’m not going to interview her women students and elicit raves about her as a role model. I’m going to be blindly, aggressively, egregiously ignorant of her gender.

I’m going to pretend she’s just an astronomer.

(via @john_overholt)


An AI Can Realistically “Paint In” Missing Areas of Photographs

This video, and the paper it’s based on, is called “Image Inpainting for Irregular Holes Using Partial Convolutions” but it’s actually straight-up witchcraft! Researchers at NVIDIA have developed a deep-learning program that can automagically paint in areas of photographs that are missing. Ok, you’re saying, Photoshop has been able to do something like that for years. And the first couple of examples were like, oh that’s neat. But then the eyes are deleted from a model’s portrait and the program drew new eyes for her. Under close scrutiny, the results are not completely photorealistic, but at a glance it’s remarkably convincing. (via imperica)


How to harvest nearly infinite energy from a spinning black hole

Well, this is a thing I didn’t know about black holes before watching this video. Because some black holes spin, it’s possible to harvest massive amounts of energy from them, even when all other energy sources in the far far future are gone. This process was first proposed by Roger Penrose in a 1971 paper.

The Penrose process (also called Penrose mechanism) is a process theorised by Roger Penrose wherein energy can be extracted from a rotating black hole. That extraction is made possible because the rotational energy of the black hole is located not inside the event horizon of the black hole, but on the outside of it in a region of the Kerr spacetime called the ergosphere, a region in which a particle is necessarily propelled in locomotive concurrence with the rotating spacetime. All objects in the ergosphere become dragged by a rotating spacetime. In the process, a lump of matter enters into the ergosphere of the black hole, and once it enters the ergosphere, it is forcibly split into two parts. For example, the matter might be made of two parts that separate by firing an explosive or rocket which pushes its halves apart. The momentum of the two pieces of matter when they separate can be arranged so that one piece escapes from the black hole (it “escapes to infinity”), whilst the other falls past the event horizon into the black hole. With careful arrangement, the escaping piece of matter can be made to have greater mass-energy than the original piece of matter, and the infalling piece has negative mass-energy.

This same effect can also be used in conjunction with a massive mirror to superradiate electromagnetic energy: you shoot light into a spinning black hole surrounded by mirrors, the light is repeatedly sped up by the ergosphere as it bounces off the mirror, and then you harvest the super-energetic light. After the significant startup costs, it’s basically an infinite source of free energy.


How to reduce opioid addiction

This morning I ran across news from two different studies about reducing deaths from opioid overdoses and they both had the same solution: medication-assisted treatment. First, from a study involving inmates in Rhode Island correctional facilities:

The program offers inmates methadone and buprenorphine (opioids that reduce cravings and ease withdrawal symptoms), as well as naltrexone, which blocks people from getting high.

The data set is small but the results are encouraging: there were fewer overdose deaths of former inmates after the program was implemented in 2016.

In the 90s, France used a similar program to cut heroin overdose deaths by 79%:

In 1995, France made it so any doctor could prescribe buprenorphine without any special licensing or training. Buprenorphine, a first-line treatment for opioid addiction, is a medication that reduces cravings for opioids without becoming addictive itself.

With the change in policy, the majority of buprenorphine prescribers in France became primary-care doctors, rather than addiction specialists or psychiatrists. Suddenly, about 10 times as many addicted patients began receiving medication-assisted treatment, and half the country’s heroin users were being treated. Within four years, overdose deaths had declined by 79 percent.


“What do census tracts with highest concentrations of particular populations look like?”

The use of satellite imagery has revolutionized many areas of science and research, from archaeology to tracking human rights abuses to (of course) climate science. This vantage point makes different sorts of observations possible than looking at ground level does.

In what she calls “a work in progress”, Jia Zhang, a PhD candidate at MIT Media Lab, used census data to collect chunks of satellite images from areas with the highest concentrations of white, black, Asian, and Native American & Alaska Native people. The result is striking (but perhaps not surprising):

Census Satellite

I’m looking forward to seeing more of Zhang’s work in this area.


Alan Turing was an excellent runner

Alan Turing Runner

Computer scientist, mathematician, and all-around supergenius Alan Turing, who played a pivotal role in breaking secret German codes during WWII and developing the conceptual framework for the modern general purpose computer, was also a cracking good runner.

He was a runner who, like many others, came to the sport rather late. According to an article by Pat Butcher, he did not compete as an undergraduate at Cambridge, preferring to row. But after winning his fellowship to King’s College, he began running with more purpose. He is said to have often run a route from Cambridge to Ely and back, a distance of 50 kilometers.

It’s also said Turing would occasionally sometimes run to London for meetings, a distance of 40 miles. In 1947, after only two years of training, Turing ran a marathon in 2:46. He was even in contention for a spot on the British Olympic team for 1948 before an injury held him to fifth place at the trials. Had he competed and run at his personal best time, he would have finished 15th.

As the photo above shows, Turing had a brute force running style, not unlike the machine he helped design to break Enigma coded messages. He ran, he said, to relieve stress.

“We heard him rather than saw him. He made a terrible grunting noise when he was running, but before we could say anything to him, he was past us like a shot out of a gun. A couple of nights later we caught up with him long enough for me to ask who he ran for. When he said nobody, we invited him to join Walton. He did, and immediately became our best runner… I asked him one day why he punished himself so much in training. He told me ‘I have such a stressful job that the only way I can get it out of my mind is by running hard; it’s the only way I can get some release.’”

I found out about Turing’s running prowess via the Wikipedia page of non-professional marathon runners. Turing is quite high on the list, particularly if you filter out world class athletes from other sports. Also on the list, just above Turing, is Wolfgang Ketterle, a Nobel Prize-winning physicist who ran a 2:44 in Boston in 2014 at the age of 56.


A high-resolution tour of the Moon from NASA

Using imagery and data that the Lunar Reconnaissance Orbiter spacecraft has collected since 2009, NASA made this video tour of the Moon in 4K resolution. This looked incredible on my iMac screen.

As the visualization moves around the near side, far side, north and south poles, we highlight interesting features, sites, and information gathered on the lunar terrain.

See also The 100-megapixel Moon and A full rotation of the Moon.


A great list of science books written by women

Scientist and educator Joanne Manaster has compiled a growing list of science books written by women (with a rule of one book per author). Some of the books and authors featured are:

Hidden Figures by Margot Lee Shetterly.

Biomimicry by Janine Benyus.

My Life with the Chimpanzees by Jane Goodall.

Silent Spring by Rachel Carson.

Black Hole Blues and Other Songs from Outer Space by Janna Levin.

The Autistic Brain by Temple Grandin.

Me, Myself, and Why: Searching for the Science of Self by Jennifer Ouellette.

The Confidence Game by Maria Konnikova.

The Invention of Nature by
Andrea Wulf.

The Sixth Extinction by Elizabeth Kolbert.

The Immortal Life of Henrietta Lacks by Rebecca Skloot.

Code Girls by Liza Mundy.

Grunt: The Curious Science of Humans at War by Mary Roach.

The Human Age by Diane Ackerman.

Manaster is soliciting suggestions on Twitter for authors she may have missed.


What makes a tree a tree? Scientists still aren’t sure…

Broccoli Tree

In Knowable Magazine, Rachel Ehrenberg writes about the tricky business of understanding what a tree is. Trees are tall, woody, long-lived and have tree-like genes, right? Not always…

If one is pressed to describe what makes a tree a tree, long life is right up there with wood and height. While many plants have a predictably limited life span (what scientists call “programmed senescence”), trees don’t, and many persist for centuries. In fact, that trait β€” indefinite growth β€” could be science’s tidiest demarcation of treeness, even more than woodiness. Yet it’s only helpful to a point. We think we know what trees are, but they slip through the fingers when we try to define them.

Ehrenberg then suggests that we should think about tree-ness as a verb rather than a noun.

Maybe it’s time to start thinking of tree as a verb, rather than a noun - tree-ing, or tree-ifying. It’s a strategy, a way of being, like swimming or flying, even though to our eyes it’s happening in very slow motion.

This reminds me of one of Austin Kleon’s strategies for How to Keep Going: “forget the noun, do the verb”. Hey, it seems to be working for the trees. (via @robgmacfarlane)


Carl Sagan’s tools for critical thinking and detecting bullshit

In his 1995 book The Demon-Haunted World, astrophysicist Carl Sagan presented a partial list of “tools for skeptical thinking” which can be used to construct & understand reasoned arguments and reject fraudulent ones.

Wherever possible there must be independent confirmation of the “facts.”

Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.

Arguments from authority carry little weight β€” “authorities” have made mistakes in the past. They will do so again in the future. Perhaps a better way to say it is that in science there are no authorities; at most, there are experts.

Spin more than one hypothesis. If there’s something to be explained, think of all the different ways in which it could be explained. Then think of tests by which you might systematically disprove each of the alternatives. What survives, the hypothesis that resists disproof in this Darwinian selection among “multiple working hypotheses,” has a much better chance of being the right answer than if you had simply run with the first idea that caught your fancy.

Try not to get overly attached to a hypothesis just because it’s yours. It’s only a way station in the pursuit of knowledge. Ask yourself why you like the idea. Compare it fairly with the alternatives. See if you can find reasons for rejecting it. If you don’t, others will.

Quantify. If whatever it is you’re explaining has some measure, some numerical quantity attached to it, you’ll be much better able to discriminate among competing hypotheses. What is vague and qualitative is open to many explanations. Of course there are truths to be sought in the many qualitative issues we are obliged to confront, but finding them is more challenging.

If there’s a chain of argument, every link in the chain must work (including the premise) β€” not just most of them.

Occam’s Razor. This convenient rule-of-thumb urges us when faced with two hypotheses that explain the data equally well to choose the simpler.

Always ask whether the hypothesis can be, at least in principle, falsified. Propositions that are untestable, unfalsifiable are not worth much. Consider the grand idea that our Universe and everything in it is just an elementary particle β€” an electron, say β€” in a much bigger Cosmos. But if we can never acquire information from outside our Universe, is not the idea incapable of disproof? You must be able to check assertions out. Inveterate skeptics must be given the chance to follow your reasoning, to duplicate your experiments and see if they get the same result.

I found this via Open Culture, which remarked on Sagan’s prescient remarks about people being “unable to distinguish between what feels good and what’s true”.

Like many a science communicator after him, Sagan was very much concerned with the influence of superstitious religious beliefs. He also foresaw a time in the near future much like our own. Elsewhere in The Demon-Haunted World, Sagan writes of “America in my children’s or grandchildren’s time…. when awesome technological powers are in the hands of a very few.” The loss of control over media and education renders people “unable to distinguish between what feels good and what’s true.”

This state involves, he says a “slide… back into superstition” of the religious variety and also a general “celebration of ignorance,” such that well-supported scientific theories carry the same weight or less than explanations made up on the spot by authorities whom people have lost the ability to “knowledgeably question.”

Yeeeeeeeep.

Update: After I posted this, a reader let me know that Michael Shermer has been accused by several women of sexually inappropriate & predatory behavior and rape at professional conferences. I personally believe women, and I further believe that if Shermer was actually serious about rationality and his ten rules for critical thinking listed above, he wouldn’t have pulled this shit in the first place (nor tried to hamfistedly explain it away). I’ve rewritten the post to remove the references to Shermer, which actually made it more succinct and put the focus fully on Sagan, which was my intention in the first place (the title remains unchanged). (via @dmetilli)


A comparison of the sizes of various microorganisms, cells, and viruses

Microorganisms are so small compared to humans that you might be tempted to think that they’re all about the same size. As this video shows, that is not at all the case. The rinovirus and polio virus are 0.03 micrometers (ΞΌm) wide, a red blood cell is 8 ΞΌm, a neuron 100 ΞΌm, and a frog’s egg 1 mm. That’s a span of 5 orders of magnitude, about the same difference as the height of a human to the thickness of the Earth’s atmosphere.

Watching the animation, you might have noticed the T4 bacteriophage, which looks like a cross between the aliens in Arrival and a lunar lander. Can’t be real, right? Bacteriophages are really real and terrifying…if you happen to be a bacteria. Bacteriophages attack by attaching themselves to bacteria, piercing their outer membranes, and then pumping them full of bacteriophage DNA. The phage replicates inside of the bacteria until the bacteria bursts and little baby bacteriophages are exploded out all over the place, ready to attack their own bacteria.


Facial recognition AIs have a hard time with dark skin

For her Gender Shades project, MIT researcher Joy Buolamwini fed over 1000 faces of different genders and skin tones into three AI-powered facial recognition systems from Microsoft, IBM, and Face++ to see how well they could recognize different kinds of faces.

The systems all performed well overall, but recognized male faces more readily than female faces and performed better on lighter skinned subjects than darker skinned subjects. For instance, 93.6% of gender misclassification errors by Microsoft’s system were of darker skinned people.

Gender Shades

Her message near the end of the video is worth heeding:

We have entered the age of automation overconfident yet underprepared. If we fail to make ethical and inclusive artificial intelligence, we risk losing gains made in civil rights and gender equity under the guise of machine neutrality.


A world-historical theory of tool use

early tools.jpg

I love reading and rereading about the origin of humanity. I love that it’s not settled science: we’re still making new discoveries about when humans first left Africa, how and when we interbred with other hominins, and what makes us human in the first place. It’s just the coolest story, which is also every story.

Popular Science has a really nice new primer on the current state of research on early humanity. Embedded in it is a series of studies on tool use by early humans in Kenya that caught my attention. Basically, the tools got smaller and more portable, the materials used were more exotic (sourced from farther away), and they were decorated with pigments.

“That’s where there’s a similarity to technology in recent times; things start out big and clunky and they get small and portable,” says Richard Potts, head of the Smithsonian’s Human Origins Program and a co-author of the papers. “The history [of] technology has been the same ever since.”

I wonder, though, if all three vectors hold up across history: greater portability, greater range of materials, and greater decorative value.

I suspect the null hypothesis would be that technologies that work tend to stay roughly the same over time. (For most of early human history, our tools didn’t change up that much, which is exactly why the burst of activity in east Africa is noteworthy.) You need something to shake things up: either sudden availability of new materials, or a deprivation of old ones (like the Bronze Age collapse, which eventually helped usher in the Iron Age).

As it turns out, that’s exactly what happened.

“One of the things we see is that around 500,000 years ago in the rift valley of southern Kenya, all hell breaks loose. There’s faulting that occurs, and earthquake activity was moving the landscape up and down. The climate record shows there is a stronger degree of oscillation between wet and dry. That would have disrupted the predictability of food and water, for those early people,” Potts says. “It’s exactly under those conditions that almost any organismβ€”but especially a hunter-gatherer human, even an early oneβ€”would begin to expand geography of obtaining food or obtaining resources. It’s under those conditions that you begin to run into other groups of hominins and you become aware of resources beyond your usual boundaries.”


“Oh My God!” People’s Reactions to Looking at the Moon Through a Telescope.

Wylie Overstreet and Alex Gorosh took a telescope around the streets of LA and invited people to look at the Moon through it. Watching people’s reactions to seeing such a closeup view of the Moon with their own eyes, perhaps for the first time, is really amazing.

Whoa, that looks like that’s right down the street, man!

I often wonder what the effect is of most Americans not being able to see the night sky on a regular basis. As Sriram Murali says:

The night skies remind us of our place in the Universe. Imagine if we lived under skies full of stars. That reminder we are a tiny part of this cosmos, the awe and a special connection with this remarkable world would make us much better beings β€” more thoughtful, inquisitive, empathetic, kind and caring. Imagine kids growing up passionate about astronomy looking for answers and how advanced humankind would be, how connected and caring we’d feel with one another, how noble and adventurous we’d be.


Gorgeous 8K video of the aurora borealis dancing in the skies during a lunar eclipse

8K resolution. Time lapse. 360ΒΊ view. Aurora borealis. Lunar eclipse. I’m not really sure how you could pack much more into this video. Probably best experienced with some sort of VR rig, but for those of us without access to such a thing, watching it several times on a large screen while dragging the view around is a more than adequate substitute. If seeing the aurora borealis in person wasn’t already on your bucket list, it is now. Dang. (via the kid should see this)


Physics giant Stephen Hawking dead at age 76

Lego Stephen Hawking

Stephen Hawking, who uncovered the mysteries of black holes and with A Brief History of Time did more than anyone to popularize science since the late Carl Sagan, has died at his home in Cambridge at age 76. From an obituary in The Guardian:

Hawking once estimated he worked only 1,000 hours during his three undergraduate years at Oxford. In his finals, he came borderline between a first- and second-class degree. Convinced that he was seen as a difficult student, he told his viva examiners that if they gave him a first he would move to Cambridge to pursue his PhD. Award a second and he threatened to stay. They opted for a first.

Those who live in the shadow of death are often those who live most. For Hawking, the early diagnosis of his terminal disease, and witnessing the death from leukaemia of a boy he knew in hospital, ignited a fresh sense of purpose. “Although there was a cloud hanging over my future, I found, to my surprise, that I was enjoying life in the present more than before. I began to make progress with my research,” he once said. Embarking on his career in earnest, he declared: “My goal is simple. It is a complete understanding of the universe, why it is as it is and why it exists at all.”

From Dennis Overbye’s obit in the NY Times:

He went on to become his generation’s leader in exploring gravity and the properties of black holes, the bottomless gravitational pits so deep and dense that not even light can escape them.

That work led to a turning point in modern physics, playing itself out in the closing months of 1973 on the walls of his brain when Dr. Hawking set out to apply quantum theory, the weird laws that govern subatomic reality, to black holes. In a long and daunting calculation, Dr. Hawking discovered to his befuddlement that black holes β€” those mythological avatars of cosmic doom β€” were not really black at all. In fact, he found, they would eventually fizzle, leaking radiation and particles, and finally explode and disappear over the eons.

Nobody, including Dr. Hawking, believed it at first β€” that particles could be coming out of a black hole. “I wasn’t looking for them at all,” he recalled in an interview in 1978. “I merely tripped over them. I was rather annoyed.”

That calculation, in a thesis published in 1974 in the journal Nature under the title “Black Hole Explosions?,” is hailed by scientists as the first great landmark in the struggle to find a single theory of nature β€” to connect gravity and quantum mechanics, those warring descriptions of the large and the small, to explain a universe that seems stranger than anybody had thought.

The discovery of Hawking radiation, as it is known, turned black holes upside down. It transformed them from destroyers to creators β€” or at least to recyclers β€” and wrenched the dream of a final theory in a strange, new direction.

“You can ask what will happen to someone who jumps into a black hole,” Dr. Hawking said in an interview in 1978. “I certainly don’t think he will survive it.

“On the other hand,” he added, “if we send someone off to jump into a black hole, neither he nor his constituent atoms will come back, but his mass energy will come back. Maybe that applies to the whole universe.”

Dennis W. Sciama, a cosmologist and Dr. Hawking’s thesis adviser at Cambridge, called Hawking’s thesis in Nature “the most beautiful paper in the history of physics.”

Roger Penrose, the eminent mathematician and physicist who collaborated with Hawking on discoveries related to black holes and the genesis of the universe, wrote a lengthy scientific obituary for Hawking in The Guardian.

Following his work in this area, Hawking established a number of important results about black holes, such as an argument for its event horizon (its bounding surface) having to have the topology of a sphere. In collaboration with Carter and James Bardeen, in work published in 1973, he established some remarkable analogies between the behaviour of black holes and the basic laws of thermodynamics, where the horizon’s surface area and its surface gravity were shown to be analogous, respectively, to the thermodynamic quantities of entropy and temperature. It would be fair to say that in his highly active period leading up to this work, Hawking’s research in classical general relativity was the best anywhere in the world at that time.

And then there was that time Hawking threw a party for time travellers but didn’t advertise it until after the party was over (to ensure only visitors from the future would show up).

Tonight is perhaps a good night to watch Errol Morris’ superb documentary on Hawking (with a wonderful Philip Glass soundtrack) or build a version of Hawking out of Lego.


The Winter Olympics, male & female physiology, and socially constructed bodies

This is a fascinating thread by Milena Popova about the differing performances of male and female athletes at the Winter Olympics. As they point out, humans are sexually dimorphic but the story doesn’t end there. Bodies are also socially constructed.

Physiology is a thing, but physiology is shaped and mediated by our social context.

Look back at those pictures of “women”. Those petite, delicate bodies, those faces we process as “beautiful”. Those are the qualities that globally dominant Western cultures associate with “femininity”.

And sport is one of the institutions that fiercely guards and reproduces dominant ideas about gender, masculinity and femininity. This plays out differently in different sports.

Generally, men and women compete separately. And for the purposes of sport “men” and “women” are defined as people whose bodies were assigned male or female at birth and whose gender matches that assignment.

The obvious example here is South African runner Caster Semenya. But Popova continues with a more subtle (and admittedly speculative) situation:

Now, what really gets me is snowboarding. Because on the face of it that’s not a sport that’s judged on the same gendered criteria of artistry and aesthetics as figure skating or gymnastics.

You’d think under all the skiing gear, helmets, scarves and goggles, it would be quite hard to perform femininity.

And still, as my friend whom I made watch slope style and half pipe for the first time in her life last night pointed out, the body types of the men and women riders are really rather different. You can tell even under all the gear.

And that translates to performance. Women get an amplitude of about 3m above the half pipe, men about 4-5m. The best women do 1080s (three revolutions), the best men 1440s (four revolutions).

But much like any other subculture snowboarding reproduces hierarchical structures. Moves are named after people, some people find it easier to access than others (hint: it’s a massively expensive sport), some people set trends.

One of the structures it reproduces is a gendered hierarchy. It’s a very masculine culture. Women find it harder to access the sport, find it harder to be taken seriously as athletes in their own right rather than “just hangers-on”.

And I have the sneaky suspicion that because the people with the most subcultural capital tend to be men and they decide whom they will admit and accept to the community, there are certain looks and body types of women who find it less hard (not easy!) to gain access.

And those happen to be the body types that may find it harder to do 1440s and to get 5m amplitude above the half pipe.

Another example from figure skating is Surya Bonaly, a French figure skater who landed a backflip on one skate in a performance at the 1998 Olympics. While backflips weren’t banned because of Bonaly’s relative ease in performing them (as claimed here), her athletic style was outside the norm in women’s figure skating, in which traditional femininity is baked right into the rules & judging. This was also a factor in Tonya Harding’s career (as depicted in I, Tonya).

Anyway, super interesting to think about.


Photo of a single atom wins science photo contest

Single Atom Photo

The UK’s Engineering and Physical Sciences Research Council just announced the winner of their annual science photography contest: a photo of a single strontium atom suspended in an electric field taken by David Nadlinger. The atom is that tiiiiny dot in the middle of the photo above.

‘Single Atom in an Ion Trap’, by David Nadlinger, from the University of Oxford, shows the atom held by the fields emanating from the metal electrodes surrounding it. The distance between the small needle tips is about two millimetres.

When illuminated by a laser of the right blue-violet colour the atom absorbs and re-emits light particles sufficiently quickly for an ordinary camera to capture it in a long exposure photograph. The winning picture was taken through a window of the ultra-high vacuum chamber that houses the ion trap.

Laser-cooled atomic ions provide a pristine platform for exploring and harnessing the unique properties of quantum physics. They can serve as extremely accurate clocks and sensors or, as explored by the UK Networked Quantum Information Technologies Hub, as building blocks for future quantum computers, which could tackle problems that stymie even today’s largest supercomputers.


Why speeding is so dangerous

Let’s say you’re doing 100 mph in a car and suddenly a downed tree, stopped car, or person appears in the road up ahead and you need to slam on the brakes. How much more dangerous is that situation than when you’re doing 70 mph? Your intuition might tell you that 70 mph is only 30% less than 100 mph. But as this video shows, the important factor in stopping a car (or what happens to the car when it collides with something else) is not speed but energy, which increases at the square of speed. In other words, going from 70 mph to 100 mph more than doubles your energy…and going from 55 to 100 more than triples it. (thx, david)


A map of the world after four degrees of warming

Four Degrees World Map

In this speculative world map published in 2009, New Scientist imagines what the world might look like if (or more likely, when) the Earth warms by 4ΒΊC. Many current coastal areas would be underwater and much of the most heavily populated areas of the Earth would be desert or otherwise uninhabitable while the northern parts of Canada and Russia would become the new bread baskets of the world. But on the plus side, western Antartica would be habitable and possibly “densely populated with high rise cities”. In an article that accompanied the map, Gaia Vince wrote:

Imagine, for the purposes of this thought experiment, that we have 9 billion people to save β€” 2 billion more than live on the planet today. A wholesale relocation of the world’s population according to the geography of resources means abandoning huge tracts of the globe and moving people to where the water is. Most climate models agree that the far north and south of the planet will see an increase in precipitation. In the northern hemisphere this includes Canada, Siberia, Scandinavia and newly ice-free parts of Greenland; in the southern hemisphere, Patagonia, Tasmania and the far north of Australia, New Zealand and perhaps newly ice-free parts of the western Antarctic coast.

The citizens of the world’s wealthiest and most populous nations will become climate refugees, which means things are going to get really, really ugly for everyone else.


Ed Yong on fixing the gender imbalance in his stories

Science writer Ed Yong noticed that the stories he was writing quoted sources that were disproportionately male. Using a spreadsheet to track who he contacted for stories and a few extra minutes per piece, Yong set about changing that gender imbalance.

Skeptics might argue that I needn’t bother, as my work was just reflecting the present state of science. But I don’t buy that journalism should act simply as society’s mirror. Yes, it tells us about the world as it is, but it also pushes us toward a world that could be. It is about speaking truth to power, giving voice to the voiceless. And it is a profession that actively benefits from seeking out fresh perspectives and voices, instead of simply asking the same small cadre of well-trod names for their opinions.

Another popular critique is that I should simply focus on finding the most qualified people for any given story, regardless of gender. This point seems superficially sound, but falls apart at the gentlest scrutiny. How exactly does one judge “most qualified”? Am I to list all the scientists in a given field and arrange them by number of publications, awards, or h-index, and then work my way down the list in descending order? Am I to assume that these metrics somehow exist in a social vacuum and are not themselves also influenced by the very gender biases that I am trying to resist? It would be crushingly naΓ―ve to do so.

Journalism and science both work better with the inclusion and participation of a diverse set of voices bent on the pursuit of truth.

Update: NY Times’ columnist David Leonhardt conducted his own experiment and discovered I’m Not Quoting Enough Women.


The Falcon Heavy launch, space advertising for billionaires, and the beauty of science

I’ve slept on it and my mind & soul are still reeling from the SpaceX launch of Falcon Heavy yesterday. I can’t tell you why exactly, but when the two side boosters landed safely back on Earth at nearly the same instant, as in a beautifully choreographed ballet, I nearly burst into tears. Just watching the replay gets me all verklempt:

Of course, the boosters were supposed to land at the same time. They broke away from the main stage at the same time and were controlled by identical computer systems in their descent; it’s a simple matter of high school physics to solve for the time it takes two uniform objects to travel from point A to point B. But as Richard Feynman said about the beauty of a flower, knowing the science makes moments like this more wondrous.

And then right after that, the video showed what appears to be a human driving a car in Earth orbit to the strains of David Bowie’s Life on Mars. What an incredible, ridiculous, ludicrous thing:

SpaceX Carman

There is ample prior art, but I suspect Elon Musk launching a Tesla Roadster into orbit will go down in history as the first notable advertisement in space, a marketing stunt for the ages. However, it seems problematic that billionaires can place billboards in orbit and then shoot them willy nilly into the asteroid belt without much in the way of oversight. As the Roadster recedes from Earth and our memory, will it become just another piece of trash carelessly tossed by humanity into a pristine wilderness, the first of many to come? Or as it ages, will it become an historic artifact, a orbiting testament to the achievement and naivety of early 21st century science, technology, and culture? It’s not difficult to imagine, 40 or 50 years from now, space tourists visiting the Roadster on its occasional flybys of Mars and Earth. I wonder what they’ll think of all this?

Update: The Roadster has been assigned an interplanetary ID by NASA: Tesla Roadster (AKA: Starman, 2018-017A). Using data from a Chilean telescope, astronomers have been able to figure out how fast the car is tumbling in space from the changes in brightness: 1 rotation every ~4.8 minutes (although there’s some disagreement in the comments that it might be twice that). At any rate (har har), here’s a time lapse video of the car taken with the 4.1-m SOAR telescope in Chile:

Astrophotographer Rogelio Bernal Andreo also captured the Roadster moving across the sky in this video:


A time lapse video where you can actually see the Crab Nebula expanding

The Crab Nebula is the result of a supernova that happened 6,500 light years away from Earth. From our perspective, the supernova happened almost 1000 years ago, in July, 1054. Using a home-built telescope, amateur astronomer Detlef Hartmann took a photos of the Crab Nebula over a ten-year period and assembled them into a time lapse video of the nebula’s expansion. Even after a millennia and across all that distance, the expansion of the nebula is clearly visible. And why not, those gases are moving at a clip of 1400 kilometers per second (more than 3 million miles per hour or 0.5% the speed of light).

As Phil Plait notes, we’re used to seeing things in our solar system move in the skies, but far-away bodies? That’s just weeeeeird.

Sure, the Moon moves in the sky, and the planets around the Sun, but deep sky objects β€” stars, nebulae, galaxies β€” are so distant that any physical motion at all is incredibly difficult to detect. They may as well be frozen in time. Being able to see it… that’s astonishing.

Hartmann’s is not the first Crab Nebula animation; I also found animations using images from 2002 & 2012, 1973 & 2001, 1999 & 2012, and 1950 & 2000. Someone with an interest in astronomy and photo/video editing should put all these views together into one 68-year time lapse of the nebula’s expansion.


Photos from the Curiosity rover’s 2000 days on Mars

Mars Curiosity Photos

Mars Curiosity Photos

Mars Curiosity Photos

NASA’s Curiosity rover has been on Mars for more than 2000 days now, and it has sent back over 460,000 images of the planet. Looking at them, it still boggles the mind that we can see the surface of another planet with such clarity, like we’re looking out the window at our front yard. Alan Taylor has collected a bunch of Curiosity’s photos from its mission, many of which look like holiday snapshots from the rover’s trip to the American Southwest.