For the curious, I’ve recently moved to Seremban and have taken up a new job. This has left me with far less free time than I had previously, so I will no longer be able to update this blog regularly. Nevertheless, I shall try my best. So here is my belated round up of three of the most interesting science related articles I came across in July. Two of the articles in this entry deal wit optics, though in very different ways. The last article is a psychological study on the values championed in television shows.
The first article is from New Scientist and covers a new range of devices that might be called social x-ray specs. It’s basically a pair of spectacles that come with a built-in camera that tracks whatever the wearer is looking at. This data is then fed into computer about the size of a deck of cards and the results displayed to the wearer inside the spectacles itself. What’s interesting about the device is what it looks for. As everyone knows, when engaged in any sort of social interaction with other people, humans will inevitably give out all sorts of unconscious physical responses to their interlocutor. Think of examples such as subtly nodding your head, arching your brow or pursing your lips.
What Rana el Kaliouby and Simon Baron-Cohen, both of the University of Cambridge in the UK, did was to use software to look out for this signals, analyze them to determine the emotional state of the person and relay that information to the wearer of the spectacles. The original intent of the exercise was to create a device that could autistic patients, who are known to have problems in interpreting social signals. But it was quickly realized that the device would be extremely useful to normal people as well. The researchers found that even normal people managed to correctly interpret the social signals only about 54 percent of the time while their software managed a success rate of 64 percent. After all, it’s very easy for someone to miss an important signal if you happen to blink or even lose concentration for a moment.
The article then goes on to cover a different but related device made by a team led by Alex Pentland of MIT. It’s a small electronic badge that a team of collaborators for a project are supposed to wear around their necks at all times. The device will measure the pitch, volume and clip of all voice communications, record who communicates with who and also note physical proximity between badge wearers. The combined data makes it possible to draw a chart detailing which people in the team are the most loquacious and which are the most silent, which pairs of people talk the most and how they talk to each other. It is effectively a social map of the team.
What was particularly interesting is that when the group was shown this map at the end of each working day, this would change the social dynamics of the group, making social interactions more even. People who talked the most would tend to speak less while those spoke the least would speak more. Pairs who talked to each other rarely would try to communicate more. The researchers claim that this increased the overall emotional intelligence of the group and improved their ability to collaborate effectively.
Both devices can be thought of as novel technologies that attempt to lubricate social interaction in ways that has never been attempted before. There are obvious advantages for this technology but the article also justly points out the ethical problems. For example, how would you feel if a salesman wore such a pair of social x-ray specs, enabling him to see your emotional response to his sales pitch in real-time while you lack the same information about him? At the very least, rules might need to imposed to force users to disclose that such a device is being actively used on the people they are speaking to.
The next article is a look at two recently published papers from Ars Technica, one dealing with a team that claims to have managed to create a material with a zero refractive index and the other on a possible use that such a material might have. Normally, materials have a positive refractive index, which is a function of how much light is slowed down while traveling through that medium compared to vacuum. Due to Snell’s Law, the direction of propagation of light is also changed when it moves between materials with different indices. Not too long ago, researchers have postulated about how a material with a negative refractive index could be used as the basis of a sci-fi cloaking device, but as far as I know, this is the first instance of anyone claiming to have made a material with a zero refractive index.
This was achieved by in effect creating a meta-material of sandwiching layers of materials with different indices, ranging from negative to positive, such that the overall index is zero, albeit for only a narrow range of light wavelengths. They confirmed that the index is indeed zero by splitting a laser beam in two, sending one of the halves through a normal medium with a positive refractive index and the other half through their meta-material and then recombining the two beams. What happens then depends on the effective distance traveled by each half of the beam. If both distances are the same, the laser will add up in phase and become brighter. If they are exactly half a wavelength apart, they will add up out of phase and there will be no light at all.
Light traveling through a zero index material should behave as if it had traveled across a distance of zero, in other words, as if it were not there at all. By comparing the combined beam at the end and seeing the effects, the researchers found that this was indeed the case for their meta-material, allowing them to declare success. As for what use this might have, another team has proposed the outlandish idea of using it as a medium through which to direct the lasers used in laser-induced fusion. In this process, hundreds of lasers need to focused on as small a point as possible. If all of the laser pulses arrive simultaneously, the combined energy can cause fusion in a pellet of deuterium. In the real-world it is extremely difficult to achieve this level of precision, but the team proposes that the lasers be built and embedded directly inside the zero-index material so that they cannot help but contribute to the unchanging field distribution. But at the moment, this is a purely theoretical pipe dream as the fabrication techniques required do not yet exist.
Finally, I think I’m as glad as the average reader that the last article for this post is much easier to parse. It’s from Science Daily and covers a study performed by psychologists at UCLA to survey the values espoused by characters in television shows popular with children from 1967 to 2007. These shows include “Andy Griffith” and “The Lucy Show”from the 1960s, “Happy Days” from the 1970s and “Hannah Montana” and “American Idol” from the 2000s. What they wanted to highlight was how these values dramatically changed from community-based ones such as benevolence, tradition, self-acceptance etc. to narcissistic ones such as fame, wealth and popularity.
For example, they found that community feeling, or the feeling of being part of a group, was the 1st ranked value in 1967, 1977 and 1997 but had fallen out of the top ten by 2007. Instead, financial success went from 12th place in 1967 to fifth place in 2007. The researchers also point out that the change was particularly dramatic in the 2000s and attribute it to the rise of social media which they claim encourage children to act as if they were constantly on a stage being viewed by potentially hundreds of other people, leading to a rise in narcissistic values.
For my part, while I included this as it certainly makes for an interesting read, I rather doubt the scientific merits of such a study. Apart from the suspicion of this being a cheap and easy way to get publicity by highlighting an “obvious” shift in television programming, I also question the methodology of selecting just two television shows to represent a decade’s worth of programming. And of course, there’s no indication in the article about how the researchers ranked the different values as they watched the episodes of each show.