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When do you think it's socially acceptable to disrobe in public?

Michael Regan/Getty Images

When do you think it's socially acceptable to disrobe in public?

At the Museum of Contemporary Art in Sydney, Australia, the artist Stuart Ringholt leads unusual, after-hours tours: art-gazing in the nude. One day last month, 32 men and 16 women signed up. The New York Times was there to document the tour, in all its glory.

The link between art appreciation and clothes-shedding is pretty tenuous. Ringholt's naked tour may strike you as a mere stunt. Yet it also leads to some interesting questions.

How do we come to be comfortable with certain patterns of dress (or undress) and wildly uneasy about others? What factors influence how different groups or individuals think about nudity and other aspects of body image?

Enlarge Don Davis/NASA

NASA says an impact with a 500-km-diameter asteroid would effectively sterilize the planet.

Don Davis/NASA

NASA says an impact with a 500-km-diameter asteroid would effectively sterilize the planet.

Sometimes death comes from unexpected places. If you were a dinosaur living some 65 million years ago, your greatest fear was probably other dinosaurs; especially if you weren't a mighty meat-eater like the tyrannosaur, who had little to fear apart from, perhaps, other mighty meat-eaters. Yet, in spite of possible downward trends in some types of dinosaurs, what finished them off was a cosmic cataclysm of untold proportions, the collision with a six-mile wide asteroid.

The impact left a 100-mile-wide crater off the coast of Mexico in the Yucatán peninsula. It's hard to imagine that a single impact could do so much damage. But doing the math, the collision with a rock that big traveling at about 20 miles per second (150 times faster than a jet airliner) would deposit as much energy as one-hundred-thousand times the energy that would have been produced by the detonating all the H-bombs that existed at the height of the Cold War. Apparently, the violence of the impact was such that the rebound shot debris half the distance to the moon.

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Mountains rise, mountains fall: change is constant.

Yuri Cortez/AFP/Getty Images

Mountains rise, mountains fall: change is constant.

The only constant is change. It's the most basic fact of human existence. Nothing lasts, nothing stays the same.

We feel it with each breath. From birth to the unknown moment of our passing, we ride a river of change. And yet, in spite of all evidence to the contrary, we exhaust ourselves in an endless search for solidity. We hunger for something that lasts, some idea or principle that rises above time and change. We hunger for certainty. That is a big problem.

It might even be THE problem.

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Heads or tails? It should be a 50-50 chance either way.

Al Messerschmidt/Getty Images

Heads or tails? It should be a 50-50 chance either way.

Last week I started a new series of micro-posts touching on the different ways quantum physics is weird. The motivation comes from my summer project of reviewing old notes and reacquainting myself with the mechanics of quantum mechanics. But no matter how many theorems on Eigenstates and Unitary operators I crank out, I am still bothered by how strange the quantum world is compared with our common sense expectations (of course the world cares not a whit about our expectations).

So today's weirdness can be summed up in a single word: probability. We are all familiar with probability. You flip a coin and before it lands there is a 50 percent chance it will come up "heads" and a 50 percent chance it comes up "tails."

The reason we don't know which side we'll get before it lands is because of ignorance.

From this primate mother to all others out there ... Happy Mother's Day!

I'm sharing here a beautiful two-minute video from the forests of Sumatra; it shows the intense, prolonged mother-infant bond among orangutans (great apes from Asia).

You can keep up with more of what Barbara is thinking on Twitter.

Let's call it Heimat is a show by Hans Schabus, a 42-year-old Austrian artist, now up at Simon Preston's gallery at 301 Broome Street in New York's Lower East Side. The focus of the show is a video installation entitled "Atelier." A roughly 10-minute loop, "Atelier" takes as its score the final shoot-out scene in Sam Peckinpah's 1969 movie The Wild Bunch. Cut for cut, and camera angle by angle, "Atelier," which documents the artist's studio and its Vienna neighborhood, is a match to the Peckinpah original.

The dynamics and visual logic of the Peckinpah battle organize our perceptual encounter with what appears to be a safe, benign urban locale. We hear the Peckinpah soundtrack, very loud — mostly the violent noise of gun fire — as it builds energetically to a bloody conclusion.

The effect is darkly hilarious and even shocking; it is mysterious and fascinating, even once you are in on the joke. (See here for a short, very positive review.)

Thanks to Bad Astronomy for posting this beautiful fly-over of the asteroid Vesta via the Dawn space probe.

Enlarge Courtesy of Farm Sanctuary

Courtesy of Farm Sanctuary

Franklin and Lila had no clue they were making history earlier this week when they went to the hospital in upstate New York.

Franklin is a piglet and Lila is a goat. Each was rescued from a life-threatening situation and taken to Farm Sanctuary's new animal hospital, the country's first to be dedicated to what a Sanctuary press release calls "the victims of America's industrialized food system."

I see the new Melrose Small Animal Hospital in Watkins Glen as an excellent step forward in how we may think about, and work to protect, farm animals.

So, the semester is over, which means I have a little more time to turn to issues that keep me awake at night. One thing I am trying to do this summer is relearn some facets of quantum mechanics I may have forgotten over the years. In the process I am getting hit over the head, yet again, with how weird the world is at the micro-level. I was thinking that it would be fun to share these little tidbits with the 13.7 community. So today I begin an ongoing series of little posts on what makes quantum mechanics so strange.

Let's start with the most basic fact. On small enough scales, the world, which seems like a seamless whole to us, resolves itself into sand. What I mean is that, ultimately, reality is granular. That is what "quantum" in physics means: "package." To paraphrase Oliver Morsch:

"The photon... is the the quantum of light and as such indivisible: it is the smallest denomination of the currency of nature representing electromagnetic radiation. With a real currency such as the dollar you can, in principle, speak meaningfully of a fraction of a cent (when quoting for instance, stock market prices) although as a physical object it doesn't exist. No so in physics. A photon cannot be divided into anything smaller, period."

What is true of a photon is also true for something like spin. The spin of a particle is quantized. There are only certain values it takes and nothing else. Everything in nature, including energy, motion and space and time comes in discreet chunks. It's as if when, walking from one side of the room to another, you could only appear and disappear from discreet locations as you cross. That is weird.

And it only gets stranger from there.

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A 2007 artist's conception of the James Webb Space Telescope in operation.

NASA

A 2007 artist's conception of the James Webb Space Telescope in operation.

Science is expensive, but the payoffs more than justify the costs. Let's focus here on basic science, that is, science that doesn't have the goal of being "useful" in the short run through technological or medical applications, and through generating wealth (usually for the shareholders). By basic science (and the boundary between basic and applied science is very blurry) I mean science for science's sake, the investigation of the fundamental workings of nature. How much should a country spend on basic scientific research?

In a time when balancing the United States' federal budget seems a distant dream, we have to ask if, indeed, a country is justified in spending billions of dollars on fundamental research. There are funding shortages in education, transportation infrastructure, modernization of the Internet, health care for millions of people and so on.

Of course, as well-argued by Nobel laureate Steven Weinberg in a recent essay for The New York Review of Books, the solution should never be to take money out of services that are badly needed, such as health care or public transportation, to sponsor scientific projects. However, the directive to invest in basic science should be a no brainer to any country that intends to either remain in, or climb to, a position of world leadership.

Walt Disney Pictures

Thor (Chris Hemsworth, left) and Captain America (Chris Evans) join up with Iron Man and the Hulk to save the Earth in The Avengers.

Way back in 1992, the great saxophonist Branford Marsalis was trying to explain to an interviewer how jazz improvisation always works within constraints. "There's only freedom in structure, my man," he said. "There's no freedom in freedom." Now it might seem like a stretch to some of you, but I think Marsalis' point holds just as true for the great new Avengers movie as it does to Bebop.

Beyond the explosions, sky-cycle-riding aliens and enormous green anti-hero, The Avengers (and the movies which led up to it) achieved a kind of greatness exactly because of its constraints. Like all grand (science) fiction they forced themselves to live within a self-consistent universe of self-consistent rules. Why does that matter? Here is why, take away the superheroes and that's exactly how our universe works: self-consistently and with self-consistent rules.

Enlarge Courtesy of Vanessa Woods

Bonobos at the Lola ya Bonobo sanctuary in the Democratic Republic of Congo.

Courtesy of Vanessa Woods

Bonobos at the Lola ya Bonobo sanctuary in the Democratic Republic of Congo.

What leads people to acts of violence and genocide? What triggers empathy and altruism? Duke evolutionary biologist Brian Hare and research scientist Vanessa Woods believe the answer may be found in the great ape known as the bonobo.

Often mistaken for chimpanzees, bonobos are slightly smaller, with longer black hair atop their heads and pink lips. Unlike male-dominated chimp culture, it's the female bonobos that rule their communities. In these matriarchal societies, alliances are strong and females gang up together on males who step out of line.

There is another difference: while bonobos live in relatively peaceful communities, chimpanzees sometimes engage in a kind of primitive warfare. These instances were famously first documented the 1970's between two neighboring groups at Gombe by primatologist Jane Goodall. Gangs of roving chimps beat, tortured, and killed their rivals to acquire new territory. Since then, other scientists in the field have recorded equally horrible and gruesome accounts of conflict. Sometimes there is even infanticide and cannibalism.

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The Roman poet and philosopher Titus Lucretius Carus (circa 95 - 55 BC)

Spencer Arnold/Getty Images

The Roman poet and philosopher Titus Lucretius Carus (circa 95 - 55 BC)

I was fascinated a few years ago to learn the initial meaning in the Greek agora and among its citizens of "rhetoric." But first, what do we now mean by the term?

Alva wrote recently about cigarette packages carrying frightening images of the consequences of smoking. He described it as propaganda, meant to manipulate, not persuade with the truth. He makes a powerful case.

We now think of rhetoric as, essentially, propaganda. Rhetoric is used to overstate and, often, misrepresent a case. In Alva's good phrase, it is used to "manipulate." In today's sense, "rhetoric" is slightly malign, intentionally misleading, not to be trusted.

Hence my astonishment when I learned (a claim I assume is true) that in ancient Greece the meaning of rhetoric — and the reason it was taught widely in Greece and the Roman Empire — was quite different.

Here is a link to an interesting piece in Science on the psychology of faith. The question raised relates to the cognitive basis for one's sense of religious belief. As the article states:

"Many people with religious convictions feel that their faith is rock solid. But a new study finds that prompting people to engage in analytical thinking can cause their religious beliefs to waver, if only a little. Researchers say the findings have potentially significant implications for understanding the cognitive underpinnings of religion."

While some folks may be offended by the very idea of the study, I think it's worth reading. Also I wonder about the difference between faith in doctrine or dogma vs. the sense of conviction arising from experience. In some sense this is the difference between religion in its institutional settings and spirituality in its personal expression.

Shanthi is a 36-year-old Asian elephant who resides at the Smithsonian's National Zoological Park (NZP). A few days ago, NZP released this video of Shanthi playing harmonica and horns, offered to her when caretakers noted the elephant's tendency to use her body in musically rhythmic ways.

The clip is brief (3:38). If you're short on time, don't miss the song Shanthi created that starts at right about 1:50. Its structure, and its ending crescendo, is pretty cool.

The NZP notes that Shanthi is never cued or coerced in her playing: it's "for her own pleasure and joy."

I wish all elephants could live safely in the wild or in sanctuaries. When they don't, this type of creative enrichment is fabulous for them.

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