Saturday, April 28, 2012

Things we don't understand. Yet.

One of the most powerful words in the scientific vocabulary is “yet”. As in “We don’t know the answer to that question. Yet.”

It’s one of the biggest challenges that the opponents of science face, trying to understand how scientists and the followers of the scientific approach can cope with not knowing things. It’s particularly hard for those followers of belief systems who offer fake certainty, all-encompassing but wrong explanations for life’s challenges and a bogus absence of doubt.

In fact science actually welcomes doubt and uncertainty. After all if the scientific method provided all the answers it would simply stop. There’d be nothing left to do, no more findings to find, no more fun to have.

The greatest of all the uncertainties we face at the moment is also the simplest to understand. Where the hell is everything?

c/o Wikipedia
Our current understanding of the universe suggests that most of the matter out there in the universe is missing. The way the galaxies are moving in relation to each other suggests that there should be a lot more “stuff” out there than we can see. Only a huge amount of missing matter could explain why the galaxies are gravitationally attracted to each other as strongly as they are. We’re pretty sure it’s out there somewhere but we just can’t see it. That’s why it’s called “dark”.

And it IS a big chunk. The mathematics suggests that something over 80% of all the matter that exists is this invisible, dark matter.

This is the biggest puzzle in physics at the moment and astronomers and theoretical physicists all over the world are doing their best to come up with a suggestion about what this stuff might be. The current consensus is that it’s not matter that’s simply hiding, it must be something entirely new, something that we simply don’t know how to detect. Yet.

For scientists this is as good as it gets. The uncertainty, this gap in humanity’s knowledge is the sexiest thing they can imagine. In order to find this dark matter they’ll need to develop new theories, new experiments and new observations that can help us solve the problem. They’re going to have to push themselves and their imaginations to the limits.

A good example of a problem that was eventually solved was the seemingly bizarre behavior of the Pioneer space probes. These were launched in the early 1970s to explore the outer planets and achieved spectacular results. After this was over a strange thing happened. As these probes disappeared into the depths of space it was noticed that they were slowing down a bit more than expected. The mission controllers knew that this would happen a bit because of the combined gravitational pull of the Sun and the planets but their calculations couldn’t explain why it was slowing down as much as it was.

A huge variety of explanations have been proposed but none seemed quite right. Scientists were puzzled and didn’t have a good explanation. Yet.

Now they have. After trawling through vast amounts of data they’ve worked out a very persuasive explanation. It’s not interplanetary material, it’s not aliens, in fact it’s nothing extraordinary at all. The solution is almost mundane but it’s still elegant. It turns out that the on-board power generators, like most power sources, radiate small amounts of heat, but the heat on the Pioneer probes wasn’t radiating equally in all directions. More thermal radiation was shining forwards, in the direction of travel, than backwards towards the Sun. It’s as if the probe was shining a torch ahead of itself. That tiny amount of “photon pressure” accounts for the tiny deceleration of the Pioneer probe.

I think this is a very good example of how a puzzle was eventually solved using old-fashioned scientific methods. The answer remained unknown for a while but eventually it was resolved. Like they all will, sooner or later. However, there is a point that it’s critical to understand. Unlike some so-called scientists in the distant past, who predicted that one day ALL scientific problems will be solved, I don’t agree. For every problem that science answers, at least one more emerges. It’s a constant struggle against ignorance. It’s also a constant fight against the peddlers of deliberate ignorance like religious fundamentalists, the peddlers so-called “alternative” medicine and the quacks who want your money.

One day we’ll beat them. Just not yet.

Sunday, April 22, 2012

Weekend Post - The science and pseudoscience of weight-loss

In all the areas of health science you’ll undoubtedly find the largest quantities of claptrap, hogwash and nonsense in the marketing of weight-loss products.

Let’s start with the basics. Despite what many so-called experts and all the charlatans and frauds will tell you, there is only one way to lose weight. Consume fewer calories than you expend. That’s it, that’s all there is to it. The best way to use excess calories is to take some exercise, the best way to reduce the number you take in is to swallow less of them.

A recent study in the USA confirmed this. Surveying over 4,000 overweight adults they examined the strategies they used to lose weight and the success or failure they experienced. The only successful strategies they found were reducing fat in the diet, increasing exercise, taking certain medications prescribed by a doctor and joining a formal weight loss program. Nothing else worked. Buying “over the counter” products achieved precisely nothing.

The other key piece of truth about sustained weight loss is that it’s never easy. It takes time for this approach to work and if you want the benefits to last you need to make these changes permanently. Long-term weight-loss requires a change in lifestyle. In the US study 63% of the sample were trying to lose weight but only 40% reported losing more than 5% of their weight and only 20% of them lost more than 10%.

This is why you see such a wealth of gibberish from fraudsters offering faster solutions or solutions that require no effort. Most of us want to avoid the hard work.

Anyone who uses Facebook may have recently seen an advertisement for "HCG Ultra Diet Drops" showing a picture of two small medicine bottles. These drops, the suppliers claim, have some remarkable qualities. They claim that if you buy these the drops you can:
"Loose 0.4kg to 1kg per day safely with an all natural homeopathic product."
Firstly that claim is just stupid. It’s impossible to lose 1kg per day, let alone safely. They go further and suggest that:
"HCG is like no other diet you have tried before. It burns the unwanted, deep tissue fat that no other diet can reach but leaves structural and normal fat."

This is, of course, complete nonsense. HCG is a hormone, human chorionic gonadotropin, that is produced by women during pregnancy but also by a growing embryo and by its placenta. As a result of some pretty dubious logic an otherwise respectable scientist, Albert Simeons, came up with a theory half a century ago that small doses of HCG, in conjunction with an extremely low calorie diet could aid weight loss. The obvious observation is that it was the absence of calories that achieved the weight loss, not the hormone but obvious facts have never deterred frauds from selling bogus cures.

The problem with this theory about HCG is simple. It’s not true. There is precisely no evidence that it is effective. Various trials have shown that it has absolutely no effect whatsoever.

What’s more the US Food and Drug Administration have instructed several companies marketing HCG products for weight-loss to stop it. They’ve also issued public warnings, one of which described the products as “Fraudulent HCG Products for Weight Loss” and another that was entitled “HCG Diet Products Are Illegal”. They say, very clearly, that “HCG products marketed as weight loss aids are unproven and illegal”. Well they are in the USA but that doesn’t stop the crooks marketing them here in Africa.

Of course one option for the fraudsters is to market these bogus products as “homeopathic” which would mean they contain no HCG at all. That’s what they say in their advertisement but it’s not what they claim when you ask them. When I emailed the Facebook advertiser, who’s based in Namibia, she told me that her drops do indeed:
"contain the HCG hormone and is a real HCG product. The market is being flooded with fake HCG products but HCG Ultra Diet Drops are not one of them."
So it’s clear. Anyone selling these drops in the USA would be fined or put behind bars but, as always, they think they can get away with it in Africa. Not only are these HCG drops useless, they’re peddled by charlatans, crooks and frauds. Isn’t it time that they were stopped from selling dangerous, pseudoscientific miracle products here as well?

Saturday, April 14, 2012

Weekend Post - Straight or gay? Why?

I was asked recently, as someone who firstly has an interest in science, but also had a brief academic background in psychology, why some people are gay. I confessed that I wasn’t entirely sure but the answer can probably be found by also asking why other people are straight.

It’s a bit like asking why some people are left-handed. You can’t separate the question from it’s sibling, why are most people right-handed?

The problem with the question is that there are many influential bodies and belief systems who think they know the answer, not from a scientific point of view, but from a “so-called” moral one. Unfortunately that’s not good enough for a scientist. A scientist is interested in evidence, not pre-formed opinions based on faith, ancient texts or something instructed by someone in pretended authority. A scientist, and indeed anyone interested in the truth, will actually be interested in facts, not opinions, whoever they come from.

The first fact that has to be faced when considering homosexuality is that it’s by no means a new phenomenon. There are records of same sex attraction and activity as far back as historical records go. It existed on every continent, including Africa, and certainly before colonialism reared it’s ugly head. There are historical records of established same-sex relationships and also more fluid attitudes towards marriage in countries as far apart as Egypt, Nigeria and Lesotho. It’s certainly NOT something new, and certainly not something introduced to Africa any more than colonialism gave us left-handedness.

Africa is no exception. Similar histories can be found in every other continent. What’s more it’s not even just humans that do it. Same-sex behavior has been recorded in species as varied as penguins, giraffe, dolphins, lions and elephants. However the most enthusiastically homosexual of our animal relatives are the Bonobo chimpanzees. Bonobos are renowned for being incredibly sexually active. They also don’t seem to care terribly what sex their partner is and use sexual behavior for a variety of social purposes, not the least of which is having some fun. Bonobos are also, whether people like it or not, our closest animal relatives. They’re not much more than a very distant cousin.

Given all of this it’s reasonable to assume that homosexuality isn’t a recent invention, not a product of colonialism and not foreign to Africa. It’s remarkably similar to being left-handed.

So why are most people straight and some gay? The simple answer is that nobody knows but what is well accepted is that it’s certainly not a choice that people make. A person’s sexual orientation seems to be a core part of their identity, again just like being left-handed. I remember a teacher in my primary school beating a child with a ruler on the back of her left hand every time she wrote or drew with that hand in a feeble effort to make her right-handed. That was just as unsuccessful as the efforts by certain evangelical church groups to “correct” or “reform” homosexuals. It simply doesn’t work. All the evidence suggests that this just causes nothing but unnecessary hardship and guilt to the recipients of the efforts made to change them.

The common question in psychology about the origins of any personal attribute is “nature versus nurture”. What in your environment or in your body’s development brought about that attribute? Much as the political left would like us to believe that all things are environmental and the right’s feeling that it’s all fate, life isn’t that simple. A small number of things are wholly environmental, such a boy’s preference for blue and a girl’s for pink, others are purely innate like eye color or handedness. Everything else seems to be a complex mixture. Despite this the current evidence is that sexual orientation is almost entirely innate. You’re simply born that way. That’s known, but the exact mechanism isn’t. It might be genetic, something you inherit, but where the evolutionary advantage comes from we don’t know. It’s certainly no advantage not to be able to have children although almost every gay man or lesbian I know has children from an earlier heterosexual relationship. They've certainly passed on their genes.

It might instead be a group genetic phenomenon where the genes of the group have to be considered. One study showed that the female relatives of homosexuals, the ones connected to the person's mother were more likely to have lots of children, but that was just one study.

A lot of current research is looking at the hormonal influences on babies as they develop in their mother’s womb. One fascinating observation is that gay men are more likely to have older brothers than straight men. This doesn’t mean that big brothers turn their little brothers gay but that as a mother gestates more and more boys something might be changing slightly in her body as time goes by. The most bizarre element of this is that this effect is only apparent when the younger brother is right-handed.

So in short we don’t currently know exactly how it works. But we do know this. Being gay or straight isn’t a choice. No normal, sane person decides what sexual orientation to have. It’s just the way they are.

Sunday, April 08, 2012

Weekend Post. We're not alone

We’re not alone

No, I don’t mean that aliens have been found, either here on Earth or anywhere else. Despite what many of the lunatics on the internet will tell you, there’s no evidence that aliens are here on Earth. Much as I like science fiction movies about alien invasions and extra-terrestrial conspiracies I recognize that they’re just fiction. Honest, they are. Also, there’s precisely no credible evidence that they’ve EVER been here. Despite what some will say, the stories about us being created by visitors from other parts of the universe are just hogwash.

However, our planet is not alone. As well as our neighbor planets in our solar system, the other planets we see in the sky, from Mercury out as far as Neptune, it seems that other stars also have planets, perhaps even some like ours.

For several years astronomers have been able to detect signs of planets orbiting distant stars. These stars, although they are close by galactic standards, are nevertheless staggeringly far away. I suspect that it’s impossible to truly comprehend how far away they are but let’s try.

A beam of light travels at an astonishing 300,000 km/s. It could travel round the Earth seven times in a second. The light you see reflected by the moon took just over a second to reach your eyes. The light from the Sun took 8 minutes to reach you. At the moment the light from Venus takes just over 5 minutes. Light from Jupiter, the biggest planet in our system, and the one you can currently see to the left of Venus just after dark, took about 45 minutes to get here. [See here for fantastically nerdy live distances to our neighbours in our solar system.]

So far everything is measured in seconds and minutes. When you consider the distances to other stars the numbers become even more extraordinary. The light from the nearest star to the Sun took more than 4 years to get here.

These other planets that have been discovered are even further away. The nearest that’s been discovered is more than 20 light-years away, meaning that the light from it takes 20 years to get here. It’s more than a million times further away from us than the Sun.

Despite them being so far away, astronomers do have firm evidence that they’re there. A small proportion has actually been seen directly but the majority have only given us indirect evidence of their existence. Some can be identified because as they rotate around their distant star they regularly pass in front of it and the amount of light we see dips slightly as a result. Others can be inferred because as they rotate around their star the star wobbles very slightly. Our most sensitive instruments can detect that miniscule wobble.

So far, using a variety of techniques, astronomers have detected over 750 of these “extrasolar planets” orbiting over 700 stars. Many of them are so massive that they’re probably gas giants like Jupiter and Saturn and are probably uninhabitable by any form of life we’d be familiar with. Others appear to be so close to their star that they’d too hot to support life. Others are probably too cold.

Although it might sound egocentric (or perhaps geocentric?), most scientists thinking about these things expect that life can only exist in conditions a bit like those on Earth, most importantly on planets where liquid water can exist. They’re looking for extrasolar planets that are just the right distance from their star, in the so-called "habitable zone". So far they’ve found just a handful.

However a recent survey of the galaxy suggests that we should expect to find more. A lot more.

The majority of stars in our galaxy are “red dwarves”, stars are generally smaller than our sun and that burn more slowly. A survey of just over 100 of these stars showed that nine of them had rocky planets like ours circulating them. Given that our galaxy contains something like 160 billion red dwarf stars and that our methods of detecting planets remain primitive, the number of planets is probably going to be measured in billions. Some have estimated that it might be as much as 40% of them. They reckon that perhaps a hundred are within 30 light years of us.

Even if a small proportion are in the realm where liquid water is possible that still leaves a very large number where life as we know it is possible. Given that life seems so abundant on Earth it would be surprising if it didn’t emerge elsewhere. We might never meet them but that doesn’t mean there aren’t aliens reading a newspaper on a distant planet right now, just like you.

Monday, April 02, 2012

I get a quantum comment

Following Saturday's Weekend Post Science article on "Quantum claptrap", I received an email.

It went like this:
"hey i am following you, i have just read this article on weekend post.

ok, my comment is that your using words like rubbish to discredit views you don't agree with is a bit intolerant. nothing in this world is absolutely certain including even our precious science. wisdom whispers: "when you feel most certain, you should doubt yourself more". pride leads leads to a rapid fall, lucifer can testify to that."
I feel absolutely no need to be tolerant of rubbish. The QXCI machine and almost everything you see in the media containing the word "quantum" is rubbish.

I'm not sure that I agree with "nothing in this world is absolutely certain". There are things I think we can agree that are convincing enough to be "certain". 2 + 2 = 4, for instance. Gravity exists. Evolution happens. X-rays exist. Precisely how how we explain these certain things might change but that doesn't affect the certainty that they exist.

The QXCI machine is a piece of worthless but expensive rubbish. Of that I'm certain.