Archive for September, 2019

Sep 17 2019

Indoor Solar Cells

Published by under Technology

Sometimes technology is developed for a specific function. At other times, however, technology is developed simply because it is possible, and then uses are found for the technology later. Most often, however, it seems that technology is developed with some specific application in mind, but once it exists out in the world many new functions are developed. In fact the “killer app” may have nothing to do with the original purpose. This is partly why it is so difficult to predict future technology, because it is impossible to replicate the effects of a massive marketplace.

This is what I was thinking when I read about a somewhat new technology – indoor solar cells. This is actually not totally new, it’s basically organic solar cells. However, the solar cells have been optimized for the spectrum of light typical in indoor environments. There are, in fact, already indoor solar cell products on the market, but they are basically just regular solar cells sized for indoor applications. What’s innovative about these new indoor solar cells is their greater efficiency in indoor environments – the researchers claim a 26.1% efficiency. Further:

“The organic solar cell delivered a high voltage of above 1 V for more than 1000 hours in ambient light that varied between 200 and 1000 lux. The larger solar cell still maintained an energy efficiency of 23%.”

That’s pretty interesting, but not surprising. We are still on the steep part of the curve when it comes to solar cell development. I reviewed the technology recently – there are basically three types. Silicon-based cells are the ones currently dominating the market. Thin film, like perovskite, are being developed and promise to be better and cheaper, but there are still some technical hurdles to overcome. They are not yet stable for long term use, for example.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 12 2019

What Is Red Mercury?

Published by under Culture and Society

I’m not a fan of the Star Trek movies reboot. While I do like the cast, and as a Trek fan I have some level of enjoyment of anything in the franchise, the movies were disappointing. As is usually the case with big budget movie failures, the problem was in the writing. Case in point – red matter. This is a mysterious substance invented by Vulcans in the future, a single drop of which could produce a singularity. It appears as a blob of red liquid. In the end it was a silly physics-breaking plot device that took you out of the movie.

I was reminded of this with recent reports of another mysterious red matter – so-called red mercury. As far as I know there is no connection between the two, and the similarity is pure coincidence. Perhaps the only connection is a psychological one. Mercury is already a fascinating substance, a metal that is liquid at room temperature. It would be fun to play with, if it weren’t so toxic. Red mercury would be an even more exotic form of this amazing element, and that is perhaps the same wonder-factor that the movie writers were going for.

In any case – as with red matter, red mercury does not actually exist. I write about a lot of things here that don’t actually exist, in order to deconstruct persistent belief in something nonexistent. People, apparently, are good at believing in things that aren’t real, a manifestation of the many flaws and limitations in our belief-generating machinery.

Beliefs can be generated and supported by a number of mechanisms – first hand experience, a phenomenon having a real effect in the world, misperception, biased memories, deliberate cons, wish fulfillment, cultural inertia, and a host of cognitive biases.  There are sufficient mechanisms of belief at work to create and sustain belief in something without any basis in objective reality. Every culture, in fact, is overwhelmed with such beliefs.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 10 2019

How the Brain Filters Sound

Published by under Neuroscience

Our brains are constantly assailed by sensory stimuli. Sound, in particular, may bombard us from every direction, depending on the environment. That is a lot of information for brains to process, and so mammalian brains evolved mechanisms to filter out stimuli that is less likely to be useful. As our understanding of these mechanisms has become more sophisticated it has become clear that the brain is operating at multiple levels simultaneously.

A recent study both highlights these insights and gives a surprising result about one mechanism for auditory processing. Neuroscientists have long known about auditory sensory gating (ASG) – if the brain is exposed to identical sounds close together, subsequent sounds are significantly reduced. This fits with the general observation that the brain responds more to new stimuli and changes in stimuli, and quickly become tolerant to repeated stimuli. This is just one way to filter out background noise and pay attention to the bits that are most likely to be important.

Further, for ASG specifically, it has been observed that schizophrenics lack this filter. You can even diagnoses schizophrenia partly by doing what is called a P50 test – you give two identical auditory stimuli 500ms apart, and then measure the response in the auditory part of the brain. In typical people (and mice and other mammals) there is a significant (60% or more) reduction in the response to the second sound. In some patients with schizophrenia, this reduction does not occur.

In fact researchers have identified a genetic mutation, the 22q11 deletion syndrome, that can be associated with a higher risk of schizophrenia and a failure of ASG. Reduced ASG may be the cause of some symptoms in these patients with schizophrenia, but is also clearly not the whole picture. It’s common for a single mutation is a gene that contributes to brain development or function to result in a host of changes to ultimate brain function.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 09 2019

Born That Way

Published by under Neuroscience

If someone is a bad person based on their behavior, are they more likely to have been born that way, or the result of environmental factors? Does it matter to how you would treat them, or how they should ethically be treated? If someone is a very good person, is their behavior the result of nature vs nurture? The actual answer to this age-old nature vs nurture debate is – it’s complicated. Both factors play a role in a complex interaction that differs for different people. It’s likely that true psychopaths were born that way, lacking an empathy circuit that most typical people possess in their brains. But of course there are also cultural norms that have a profound effect on our behavior.

Psychologists have been asking a slightly different question – not what the answer objectively is, but what do people assume that it is, and how does that affect their behavior toward other people. The assumption or belief that behavior is due primarily to instrinsic factors is called essentialism. A recent study looked at both children and adults and how they thought about characters with both morally good and morally bad behavior. Prior research suggests that in general we tend to attribute other people’s behavior to essential factors. People don’t just do good vs bad things, they are good vs bad.

This is part of what psychologists call the fundamental attribution error. We tend to attribute our own behavior to external factors and other people’s behavior to internal factors. I am the victim of circumstances beyond my control, but that other person (perhaps acting in an identical way) is just a bad person.

The new study adds some further nuance to this effect. They found that study participants (both children and adults) were more likely to attribute good moral behavior to essentialist causes than bad moral behavior. So if someone does good things, it’s because they are a good person. If they do bad things, it’s because of their bad environment. This is an interesting result, and suggest several questions to me. First, how universal is this? Is that result itself a product of learned behavior, a product of our time and culture? Would the result have been different in the 1950s in the US, and would it be different in other countries? I would also be interested in seeing how the results differ based on ideology.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 06 2019

Information Gerrymandering

Democracy, in a very real sense, is math. The point is to aggregate decision-making in order to arrive at the fairest outcome for the greatest number of people. Andrea Jones-Rooy, who spoke at NECSS this year, gave a great lecture about this. Here is an article she wrote about Arrow’s Theorem that goes over the basic concept, but she went into more detail during the talk. Essentially there is no system of voting that has perfect fairness (ranked choice vs least objectionable option, for example), so we just have to pick one and live with the trade-offs.

Jones-Rooy, however, was talking about different systems that work as intended, no cheating. If, however, one group puts their thumb on the scale, the democratic process can be massively distorted. Beyond a certain point you no longer even have a true democracy. Voting becomes a sham used to give a patina of legitimacy to a dictator or minority rule.

Perhaps the best known form of voting distortion in the US is gerrymandering. The best description I have heard of this is that it is a way for politicians to choose their voters, rather than voters to choose their politicians. The idea is to carve up voting districts deliberately to favor one party, so that even if they have 40% of the voters in one state, they can secure 60% or more of the representatives. (This doesn’t work for senators or presidents where voting is state-wide.)

Researchers, however, have published an article in Nature in which they describe a more insidious form of distortion – information gerrymandering. This amounts to a rigorous mathematical description of a phenomenon we have been discussing, the effect of social media networks on public opinion. They found:

Players are assigned to competing groups (parties) and placed on an ‘influence network’ that determines whose voting intentions each player can observe. Players are incentivized to vote according to partisan interest, but also to coordinate their vote with the entire group. Our mathematical analysis uncovers a phenomenon that we call information gerrymandering: the structure of the influence network can sway the vote outcome towards one party, even when both parties have equal sizes and each player has the same influence.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 05 2019

DNA Analysis of Loch Ness

Published by under Skepticism

If you have never been to the highlands of Scotland, add it to your list of places you should visit. It is incredibly beautiful. When I was there last year we visited Loch Lomond of lyrical fame, and also the largest lake in Great Britain. We were given the option of instead visiting Loch Ness, and we had to explain to our guide that she had a bus full of skeptics. She was relieved because she thought Lomond was the better destination, but of course most tourists want to see the more famous Loch.

The legend of the Loch Ness Monster has now taken on a life of its own, and it seems unlikely that any evidence, no matter how definitive, will kill it. Rumors of a monster in the Loch go back centuries, but the modern myth was kicked off by the famous Surgeon’s Photo. In 1934 Colonel Robert Wilson, a British surgeon, published his now iconic photo. His accomplice later confessed this was a hoax, using a model built out of a toy submarine and a clay head (which I always thought looked like it was modeled after an arm and hand). But it was too late, a myth was born.

A recent headline from the BBC now declares: “Loch Ness Monster may be a giant eel, say scientists.” The problem with this claim is that there is no Loch Ness Monster, so it can’t be anything. Of course they mean that giant eels may be responsible for Nessie sightings, but even this is misleading. There is likely no single phenomenon responsible for the continued sightings of something unusual in Loch Ness.

Continue Reading »

Like this post? Share it!

No responses yet

Sep 03 2019

The Politics of Nuclear Power

Published by under Technology

Our president is a global warming denier, is anti-vaccine, and is a conspiracy theorist. Regardless of where you are on the political spectrum, being anti-science is never a good thing. When those in positions of power are ignorant of science and hostile to the institutions of science and the methods that those institutions espouse, that is a recipe for disaster.

But even a stopped clock is correct twice a day. And even though there appears to be a significant asymmetry in the degree to which our two major political parties take anti-scientific positions, on some issues the political left has it wrong for their own ideological reasons. The two big anti-science issues popular on the left are anti-GMO stances and anti-nuclear energy. The latter was recently brought into sharp relief when Trump signed a, “Memorandum on the Effect of Uranium Imports on the National Security and Establishment of the United States Nuclear Fuel Working Group.” 

I doubt that Trump, who has demonstrated profound anti-intellectualism and even an unwillingness to read, has a deep knowledge of the scientific issues surrounding nuclear power, but he is a conduit for those who do, unfettered by political opposition (which remains on the left). Meanwhile, Bernie Sanders, in his version of the green new deal, states, “To get to our goal of 100 percent sustainable energy, we will not rely on any false solutions like nuclear, geoengineering, carbon capture and sequestration, or trash incinerators.” He plans to completely and quickly phase out all nuclear power in the US.

I have to point out for completeness that more moderate Democratic candidates, like Joe Biden, do include nuclear power in their energy infrastructure plans to combat global warming.

Also, attitudes toward nuclear power have been moving toward more favorable in recent years. This seems to be due to a few factors. The more people know about nuclear power, the more favorable they are towards it. Fears about global warming have caused some to moderate their views on nuclear energy. And newer reactors designs are moving toward smaller and safer designs.

There is still an asymmetry politically, however. Only 31% of Democrats say that nuclear power is essential or helpful, while 34% say it would be harmful. For Republicans the numbers are 50% and 17% respectively.

Continue Reading »

Like this post? Share it!

No responses yet