Sure, a laser can shine finely-tuned light to do anything from scanning your barcodes to correcting your vision, but soon that precise hero may meet its match: Physicists have recently imagined a device that can absorb light of certain frequencies, an “anti-laser.”

Absorbing light may not seem all that impressive, since after all, anything that appears black works as an absorber. Your driveway, however, is not the anti-laser. A paper in the Physical Review Letters lays out the plans for this device which can absorb light wave clones (same frequency, phase, and polarization) that some lasers emit. The pickiness of this theoretical light absorber is part of what would make the device unique, just as an important part of what separates a laser from a flashlight is the precision of the light a laser emits.

Instead of amplifying light into coherent pulses, as a laser does, an antilaser absorbs light beams zapped into it. It can be “tuned” to work at specific wavelengths of light, allowing researchers to turn a dial and cause the device to start and then stop absorbing light. “By just tinkering with the phases of the beams, magically it turns ‘black’ in this narrow wavelength range,” says team member A. Douglas Stone, a physicist at Yale University. “It’s an amazing trick.” [Science News]

The Yale University team has gone through the numbers for such a choosy absorber, which works partly by switching the material that reflects light in a laser with material that instead absorbs it. The paper describes a theoretical device using silicon.

A paper-thin slice of silicon would normally absorb about 20 per cent of the incoming light, but the team showed that in this set-up it would cancel nearly all of the light at 945 nanometres, in the near infrared…. So far the effect exists only on paper, but team member Douglas Stone says “ongoing experiments are extremely promising, and I have total confidence it can be realised”. [New Scientist]

Given the specificity of the light that this absorber requires it is unlikely, a Physics review says, to find future employment as part of a solar panel or stealth cloak (shielding a ship for example from radar). Instead, such a device could likely appear in pairs with lasers forming “optical switches” in circuits–and perhaps as the weapon of choice for science fiction foes.

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Image: Wikimedia / Jeff Keyzer

Hounds, pointers, and other dogs bred for their excellent abilities to pick up a scent tend to have longer snouts—but it’s not just that a bigger nose is a better one. Researchers have found that human domestication of dogs has shifted the structure and alignment of some dogs’ brains. And in those varieties with shorter snouts—which humans bred for other reasons, like appearance—the olfactory brain region rotated to a different part of their skull, leaving scientists to question whether we’ve crossed up their smelling abilities (and perhaps more).

Since the first wolf was domesticated an estimated 12,000 years ago, “selective breeding has produced a lot of [anatomical] variation, but probably the most dramatic is in terms of skull shape,” said study co-author Michael Valenzuela [National Geographic].

For this study, which appears in the open-access journal PLoS One, Valenzuela and colleagues examined the brains of 11 dog breeds and found great variation in the size and shape of their skulls. The breeds with shorter snouts had brains that rotated forward by as much as 15 degrees over the generations, the scientists say. That means that the olfactory lobe, as well as other parts of these dogs‘ brains, has shifted position and shape because humans guided their evolution through domestication.

Valenzuela says that in particular humans might have altered the dogs’ rostral migratory stream, or RMS, a connection in the brain that’s important for the sense of smell.

“The RMS starts very deep in the middle of the brain and traces a very predictable path to the olfactory bulb…. Since the olfactory bulb has moved in brachycephalic [short-snouted] dogs, you’d expect to see a change in the course of the RMS, or it may be disregulated” [National Geographic].

The researchers don’t know yet how much the brain changes affect the dogs and their world of smell. But they say the differences in brain size are another surprise showing how diverse dogs can be.

As Dr. Valanzuela explains, the most astounding thing is that dogs’ brains can actually handle such huge differences in the shapes of the skulls that house them. Dogs have already shown unprecedented levels of variety in their different physical breeds, but the variation in brain organization is an even more fundamental and thus more incredible form of diversity across the species [io9].

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Image: Wikimedia Commons

Meryl Dorey, head of the flailing Australian Vaccination Network — an organization dedicated to twisting the truth about vaccines and saying anything at all to scare people into an antivax stance — has once again put fingers to keyboard, and as usual the truth eludes her.

She wrote a lengthy essay about her dealings with Toni and David McCaffery, who lost their four week old infant Dana to pertussis two years ago.

I hardly need to point out that her interpretation of reality doesn’t come within a glancing blow of it; you can read what Dorey wrote, and then compare it to Toni McCaffery’s response detailing what really happened, and why Dorey is so wrong.

I also received a note from David McCaffery about a terrific site that helps educate people about vaccines: Chain of Protection. They have really good videos describing benefits of vaccinations. Here’s the one about herd immunity which shows just why it’s important:

Herd Immunity – How it works from Chain of Protection on Vimeo.

Check out the site. It’s what Meryl Dorey wouldn’t want you to do.