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Posts tagged: science

Accurate and honest metric weights and measurements

My height is 1 metre and 78 centimetres. I refuse point-blank to quote that in feet and inches.

My weight, as of 12:30 on Saturday 19 August, is 79.8 kilograms. One again, I don’t care what that is in stones and pounds, so working it out is left as an exercise for the reader.

Over the past three months I have made it my goal to take a five kilometre walk every day that I can. Once again, converting that into miles is left as an exercise for the reader.

Those who have engaged in discussions with me in (sometimes lively) debates about science and faith will be aware that one particular passage from the Bible that I am always quoting, over and over again, is Deuteronomy 25:13-16, which says this:

13Do not have two differing weights in your bag — one heavy, one light. 14Do not have two differing measures in your house — one large, one small. 15You must have accurate and honest weights and measures, so that you may live long in the land the Lord your God is giving you. 16For the Lord your God detests anyone who does these things, anyone who deals dishonestly.

It should come as no surprise, therefore, to learn that I am an ardent proponent of metrication, frustrated at the lack of progress that the UK has made in this area since the initial push in the 1960s and 1970s, and totally opposed to any attempt to head in the opposite direction.

This one should be a no-brainer. With the exception of the UK, the USA, Myanmar and Liberia, almost every other nation on Earth uses metric units exclusively. It’s not hard to see why either. Metric units of measurement make sense. Different measurements of the same units are related to each other by multiples of ten, with a consistent set of prefixes denoting their relationships. So getting from metres to kilometres, grams to kilograms, bytes to kilobytes and so on, you just notice the word “kilo” at the start and multiply by one thousand.

On top of that, metric units, or SI units, are the foundation for measurement in science, engineering, commerce, finance, law, education and just about every other context where measurement is used. They are based on well defined, easily measurable, high-precision quantities. They are consistent, unambiguous, precise, easy to understand, easy to work with, internationally recognised, and exactly the same everywhere you go. They are the lingua franca of accurate and honest weights and measurements worldwide.

Imperial measurements, by contrast, are a mess. There are sixteen ounces in a pound and fourteen pounds in a stone—or is it the other way around? Up until the nineteenth century, the number of pounds in a stone varied depending on where you were and on what was being measured. There are eight furlongs in a mile, ten chains in a furlong, 22 yards in a chain, three feet in a yard, twelve inches in a foot … how on earth are you supposed to remember all the details? British and American gallons are different. British and American tons are different. I have no idea how much a fluid ounce is supposed to be. Repeat after me: an acre is the area of a rectangle whose length is one furlong and whose width is one tenth. None of it offers you a shred of sense or coherence whatsoever.

Someone asked me the other day on Facebook, in response to my quoting of Deuteronomy 25 yet again, whether I thought that having a mixture of imperial and metric measurements was unbiblical. I replied that it quite possibly could be. Having two different systems of measurement makes it a whole lot harder for consumers to compare like for like when trying to figure out how much something costs. Supermarkets being supermarkets, they will take every opportunity they legally can to pull off shenanigans like that. This was a concern back in the 1970s when the push for metrication was in full swing, and it would be a concern if we were to try to turn the clock back to imperial ones again.

Unfortunately, there are certain politicians here in the UK who, in the wake of Brexit, want to do precisely that. One of the most prominent of these is, of course, the Right Honourable Member for the eighteenth century, Sir Jacob Rees Mogg, who instructs his staff, in no uncertain terms, that imperial measurements they must use. The only reason why anyone would want to do things such as this is some sort of misguided rose-tinted nostalgia for the good old days of the 1940s and 1950s or earlier. Why don’t we just bring back post-war rationing, outside loos, black and white TV, and horses and carriages while we’re at it?

Supergiant stars are hot vacuums

You may have seen this video showing the relative sizes of different stars, and how massive some of them are:

What’s often not appreciated is that as well as being mind-bogglingly large, the largest supergiant stars are also incredibly tenuous.

Just how tenuous? Let’s take Betelgeuse as an example. There’s some uncertainty about the exact figures, but it has a mass about eleven times that of the sun, and a radius of about 900 solar radii. In other words:

Mass:2.2×1031 kg
Radius:6.3×1011 m
Volume:1036 m3
Density:2×10-5 kg/m3

On earth, a density of just 2×10-5 kg/m3 would be considered a hard vacuum. It is just one sixty thousandth of the density of the earth’s atmosphere, 1.2 kg/m3. The density of the largest known star in the video, VY Canis Majoris, is roughly similar.

Yet despite this, this gives Betelgeuse an escape velocity of about 70 km/second at its outer extremity. Betelgeuse’s enormous size is due to extreme nuclear fusion reactions in its core, where helium is converted into carbon and oxygen, and then subsequently into heavier elements, culminating in the conversion of silicon to iron. Once its supply of silicon is exhausted, nuclear fusion is no longer possible, the star collapses in on itself, and a supernova explosion results. For Betelgeuse, it is estimated that this will happen sometime in the next million years or so.

What is xkcd “Time” all about?

You can’t go far on the Internet these days without coming across the webcomic, xkcd, by Randall Munroe. Three times a week, he publishes comics giving a twist on science, pop culture, and general knowledge, that are amusing, informative, and at times pretty cryptic. Every so often, he posts something that reaches epic proportions. One of his most spectacular creations was comic number 1190 — “Time.”

At first glance it appears to show this particularly puzzling looking picture:

What is it? And what does it represent?

A brief history of Time

“Time” is, in actual fact, a masterpiece of storytelling that won the 2014 Hugo Award for Best Graphic Story. What you see here is the last frame in an epic series of 3,099 different images that were updated on the hour, every hour, starting on March 25, 2013. For the first five days, they were updated every half hour, but the frequency changed to hourly on March 30. It continued updating with a new picture every day until late July that year. If you click through the picture on the xkcd site, you will be taken to another website, which allows you to scroll through the images and follow the story.

The first picture was every bit as puzzling as the last. It simply showed two characters (known to xkcd fans as Cueball and Megan) sitting on a beach:

The tooltip that appeared when you hovered over the picture initially said, “Wait for it.” So we waited.

Over time, as the story unfolded, we saw them building a sandcastle of epic proportions:

As they worked, they noticed something strange: that the sea was rising. Further, and faster, than they’d ever known it to rise before.

Why is the sea rising? Where is the sea anyway? If you want to see the whole story first, head over to the geekwagon viewer. You may want to do so now because the rest of this post contains spoilers.

Eventually, our twosome decide to set off on a journey to try and find out why the sea is rising. On the way, they encounter some epic scenery, including rivers:



Abandoned dwellings:

They get attacked by a large cat:

After fending off the cat, they spend a tense night out in the open, sleeping beneath the stars:

And finally they meet up with some people in woolly hats who speak a strange language:

The Beanie Bunch take them to their leader, who explains to them why the sea is rising:

The leader then shows them a map telling them how far she thinks the sea will rise, and at this point, all is revealed:

What happened to the Mediterranean?

It turns out that the Straits of Gibraltar had become blocked, the Mediterranean had dried up, and Cueball and Megan were members of a small settlement of just forty people living by the shores of a small, hyper-saline sea at the bottom of the Mediterranean basin, a bit like the Dead Sea of today. But now the blockage at the straits had been breached, water was starting to flow into the basin, and that was why the sea was rising.

This is something that has actually happened before. There is a lot of evidence that 5.97 million years ago, the Straits of Gibraltar were blocked up by the northward movement of the African continental plate towards Europe. This precipitated a period called the Messinian Salinity Crisis, in which the Mediterranean Sea dried up. We can see the legacy of this event in the vast deposits of halite (i.e. salt) on the floor of the Mediterranean basin, and also in large, now filled-in canyons that were carved by the Nile and other rivers that flow into it.

The Messinian Salinity Crisis came to an end about 5.33 million years ago, when the Straits of Gibraltar were breached one last time, in an event called the Zanclean Flood. It is estimated that the Mediterranean took several months to two years to fill up again, with torrents of water flowing in from the Atlantic at a rate a thousand times greater than the flow of the Amazon river. It left its mark by cutting the Straits of Gibraltar into a deep and wide channel, whose maximum depth today is 900 metres.

It turns out that the events of Time are set about 10,000 years into the future — in April, 13291 AD to be precise. What caused the Mediterranean to be blocked up this time round is not stated, but it could perhaps have been an engineering mega-project sometime in the next thousand years or so. There have been ambitious proposals made in the past to dam up the Straits of Gibraltar, lower the level of the Mediterranean, and create massive amounts of hydroelectric power and open up new lands for settlement. The likelihood of such proposals ever being implemented, however, is low, to say the least.

What happened to Cueball and Megan?

Ah, spoilers! You’ll just have to visit the Geekwagon viewer to see the whole story.

Now can somebody please make this delightful epic into a Hollywood movie?

New blog on creation and evolution

In the past few months I’ve written a couple of posts here on my blog about my forays into the creation and evolution debate. However, since I’d rather keep this blog focused on subjects related to my professional work with software development, DevOps, and this Parliament-as-a-service startup that I’m working at, I’ve started up a separate blog to act as a brain dump for everything that I’ve learned about the subject over the past couple of years.

At the moment I’ve got it set to publish a new post every Monday every week through until September.

In case you hadn’t already figured out, my position on the matter is 100% evangelical Christian but also 100% old-earth. I’m sorry folks, but the earth simply isn’t six thousand years old, it’s as simple as that. The Bible does not require it, and the evidence does not support it and can not be re-interpreted to support it without descending into absurdity or dishonesty or both.

I’m generally tending to focus more on the physical sciences side of the debate — dating methods, geochronology, astronomy, and so on. Not being a biologist, I don’t tend to have much to say about evolution itself. Not unless you’re making claims about it that are blatantly clueless, such as that it’s “only a theory,” or that it contradicts the Second Law of Thermodynamics, or that mutations can’t produce new information, or that there are no transitional fossils, or silly straw man arguments about cats not turning into dogs. All I ask is that you make sure that you know what you are talking about, and that your facts are straight.

Ten things you need to know about the age of the earth

Now as I keep saying, my position on the whole creation and evolution debate is simple.

Make sure that your facts are straight.

Genesis 1-11 is a part of the Bible that leaves a lot open to interpretation, and while it may seem audacious and bold and uncompromising and full of faith to opt for the most radical interpretation (a Literal Six Day Young Earth Creation, non-evolution, dinosaurs on Noah’s Ark etc), if you’re supporting this position with demonstrable falsehoods and displays of ignorance, you won’t be upholding the Bible; on the contrary, you’ll be undermining it.

Unfortunately, I frequently see well-meaning but badly informed Christians making claims about the age of the earth, and about how it is determined, that are demonstrably and indisputably untrue. Some of these are just rumours and hearsay, and some of them just demonstrate ignorance, but there is also a lot of misinformation out there being published by certain people with PhDs who should know better.

So before you rush into the debate with all guns blazing, here are ten things that you need to know about the age of the earth, the ages of rock strata, and how they are determined.

1. It is based on measurement and mathematics, not on guessing or presupposition.

I sometimes hear people claiming that determining the age of the earth is “guessing at best,” or that if you looked at the evidence with different, young-earth “glasses,” you’d get different, young-earth results. Or that old-earth results are based entirely on an a priori commitment to the theory of evolution and philosophical naturalism.

This is nonsense. The age of the earth is determined first and foremost by measuring things. Measuring and guessing are complete polar opposites, and measuring anything gives the same result no matter what “glasses” you look at it through. You could look at Mount Everest with glasses that make it look like it’s just four inches high all you like, but that won’t stop you from getting a height of 8,848 metres when you actually measure it.

Anyone who tells you that rocks don’t come with time stamps doesn’t know what they’re talking about. Rocks contain radioactive elements such as uranium-238, potassium-40, rubidium-87 and so on, which decay exponentially at well-established rates. When a rock cools below a certain temperature (the “closure temperature”), these elements are “locked in” in ways that follow certain highly predictable patterns. Scientists can then take samples from the rocks, measure their composition, determine how much these patterns have changed, and in that way determine the age of the rock.

You may have heard that radiometric dating has to make assumptions about the original composition of the rocks — how much of the “parent” and “daughter” isotopes were originally present. This is not true. There is a technique called isochron dating which avoids this assumption altogether. By taking multiple samples from the rock, you can plot a graph of 87Rb/86Sr against 87Sr/86Sr: its slope will give the age of the rock without having to know anything about its original composition. If there has been any contamination or leakage, the points on the graph will not lie on a straight line.

2. Its assumptions can be — and are — rigorously tested.

The claim that “historical science” relies on assumptions that can’t be tested because nobody was there to check (the “were you there?” argument) is simply not true. Historical assumptions can easily be tested by cross-checking different dating methods whose assumptions are independent of each other.

One particularly spectacular example comes from measuring rates of continental drift. In places such as the Hawaiian islands, the dates of lava flows increase linearly with distance from the hot spot in the earth’s crust over which the various islands have formed. In recent years, it has also become possible to measure continental drift directly using GPS. Everywhere we look, the measurements are exactly the same within the measured range of errors.

I’ve occasionally seen claims that different methods only give the same results because they make the same assumptions of uniform rates, or because they adopt the same worldview. This is patent nonsense. The whole point of cross-checks is to test assumptions, not to make them. In any case, any alternative explanation in which the rates weren’t constant would need to have something affecting all the different measurements in exactly the same way, in exactly the same proportions, in exact lock-step with each other, by a factor of up to a million. Since the different rates include nuclear decay, continental drift, formation of tree rings, lake varves, ice core layers, coral growth and a whole lot of other things as well, such a proposition is quite frankly preposterous.

3. Its reliability is measured and calculated as well.

The scientific consensus is that the age of the earth is 4.54 ± 0.05 billion years.

Note the second part of that figure — ±0.05 billion years. It indicates an uncertainty of just one percent. It means that scientists have a 95% confidence that the age of the earth is no younger than 4.49 billion years and no older than 4.59 billion years. Uncertainties fall away exponentially as you move away from the centre of the range, and the chance that the error could be even three or four times as big as that figure is so low as to be effectively zero.

Error bars and uncertainties are not guesses either. They are determined by taking multiple measurements and calculating a statistical property called the standard error of the mean — a precisely defined quantity derived from the “spread” of the results about their average value. There are similar formulae for how to calculate uncertainties when calculating the slope of a graph.

This figure also takes into account the confidence levels that scientists have that rates such as nuclear half lives are constant. They do not blindly assume that these quantities never changed in the past; on the contrary, they study the evidence to determine limits to how much these quantities could have varied over billions of years. These limits are plugged into their formulae.

The end result gives an error of just one percent. Your car’s speedometer is less accurate than that. And six thousand years falls so far outside of this error range as to be ridiculous.

For what it’s worth, the fact that its uncertainty is known contradicts the claims of some YECs that old-earth ages merely arise from old-earth presuppositions designed to make space for evolution. There is no possible way whatsoever of starting off with vague, non-specific “old-earth presuppositions” and ending up with a final result that is constrained to within just one percent.

4. Much of the evidence comes from the oil industry.

Jonathan Baker, a Christian geochronologist and author of the Age of Rocks blog, explains this quite clearly in his article, “Can Young Earth Creationists Find Oil?” As he explains, oil companies need to know both the ages of the oil deposits and their geothermal history. Too young, or too cool, and the deposits will be “premature” — still solid, and impossible to get out of the ground. Too old, or too warm, and they will have been baked into oblivion.

There is no way that petroleum geologists could be artificially inflating the ages of oil deposits and rock strata in order to accommodate an evolutionary worldview. They are paid to produce results that are correct, not results that are ideologically convenient. If their measurements really were ideologically motivated in that way, oil companies would waste a fortune (and a lot of political good will) drilling in all the wrong places, the geologists would be fired and spend the rest of their working lives flipping burgers in McDonald’s, and the radiometric labs would be sued out of their insurances.

5. There is no circular reasoning involved.

The claim that “fossils are used to date rocks and rocks are used to date fossils” is so misleading that it is, to all intents and purposes, a flat-out lie. Rocks that are used to date fossils are dated first and foremost by radiometric dating. Index fossils are then only used to date rocks that can not be dated radiometrically. There is nothing circular about that.

Similarly, claims that nuclear decay rates are determined from known ages of rocks are also misleading. This would only suggest circular reasoning if this were the only way that these rates were determined. It is not.

Reasoning is only circular if you have two different lines of evidence that both depend entirely on each other. In every claim of supposedly circular reasoning that I have seen, there have been other independent lines of evidence involved which haven’t been mentioned that break the circularity.

6. Fewer than 10% of radiometric results are “bad.”

There is a vast difference between “doesn’t always work” and “never works.”

Young earth organisations love to point out cases where radiometric dating didn’t work — for example, when different methods gave wildly different, or otherwise apparently wrong, results. However, if radiometric dating really were a chaotic mess that couldn’t distinguish between thousands and billions of years, these “bad dates” would be ubiquitous, while close agreement between different dating methods would be all but non-existent.

This is not the case.

Dr. G. Brent Dalrymple, one of the foremost experts on radiometric dating, estimates that no more than 5-10% of radiometric results are “bad.” In other words, more than ninety percent of the time, there is no disagreement; the resultant dates are as expected; and different dating methods do indeed give the same result.

Anomalous dates are not unexpected, and usually indicate that the rocks in question had a complex geothermal history, being heated sufficiently at one point or another to partly reset their “clocks.” However, far from demonstrating that radiometric dating never works, the fact that these cases are the exception rather than the rule demonstrates that 90% of the time, it works just fine.

In any case, there are over forty different isotopes used in radiometric dating, and each will work for some kinds of samples but not others — again, cross-checks between different methods tell us which is which. The fact that carbon-14 does not work on traffic cones, for example, does not prove that uranium-238 does not work on zircon crystals in granites.

Furthermore, the disagreements between different radiometric dates catalogued by the RATE project differed by up to about twenty percent. Disagreements of just twenty percent in a minority of results do not justify claims that all dating methods are systematically in error by a factor of up to a million.

7. Radiometric dating is expensive.

The number of samples that have been dated by multiple methods, with no surprises and with an agreement to within one percent or better, to ages far in excess of six thousand years, runs into the hundreds of thousands. Each sample costs as much as a small car to collect, store, process, and analyse in order to determine a date.

If “evolutionists” really were “throwing out dates that don’t fit their preconceived notions,” millions of results costing hundreds of billions of dollars in total must have been discarded over the past sixty years or so.

Why are there no accountants and bean counters creating a stink about this colossal amount of money being thrown away on wholescale scientific fraud? Given the number of young-earth creationists in the US Congress, why are none of them proposing the simple fix to the problem of requiring pre-registration of all radiometric studies? And why is there nothing about it on Wikileaks?

8. There are no reliable findings of primordial radiocarbon in ancient coals and diamonds.

The RATE project, a young-earth creationist research project that ran from 1997 to 2005, claimed to have found carbon-14 in ancient coals and diamonds that by rights should not have contained any.

Their work was reviewed by Kirk Bertsche, an evangelical Christian radiocarbon expert, who pointed out that not only were the amounts of radiocarbon very low, they also showed clear patterns that were characteristic of contamination. For example, the amount of radiocarbon in heavily processed samples was found to be much higher than those that had undergone comparatively little processing.

Furthermore, he pointed out that although they did attempt to take contamination into account, they did not follow the correct procedures for doing so. High-end radiocarbon laboratories go to extreme measures to avoid contamination, even so far as operating in specially constructed buildings with shielding against cosmic rays. The RATE team merely subtracted a “standard background.”

Contamination in carbon-14 dating is well studied and its vectors are well known. Before ancient samples can be demonstrated to contain primordial radiocarbon, contamination must be rigorously eliminated. To date, no finding of primordial radiocarbon in ancient coals and diamonds has adequately done so.

9. Young-earth “evidences” are based on low-precision measurements and unrealistic assumptions.

Consider the amount of salt in the sea — quoted by Answers in Genesis as one of their ten best evidences for a young earth. A number of things are immediately obvious.

  • It is based on rates that are extraordinarily difficult to measure, requiring massive international surveys.
  • No error bars in the measurements are quoted; only a vague hand-waving claim about being “generous to uniformitarians.” The error bars would almost certainly be large — well above ±10% for many of the different factors involved.
  • It is based on rates that can not realistically have been the same in the past as they are today, even in a “uniformitarian” model.

When up to date, accurate figures are used and everything is taken into account, a state of equilibrium — where the long-term amount of salt leaving the sea is the same as the amount entering it — is well within the range of experimental error. In fact, there is no evidence that the seas really are getting saltier with time.

Now compare that to radiometric dating.

  • It only requires a relatively small number of measurements (a few dozen) from each rock formation.
  • The error bars in both the measurements and the final result are a fraction of ±1% or better, and are always quoted.
  • It is based on rates that can not realistically have varied in the past without proposing radical new laws of physics for which there is no evidence whatsoever.

The amount of salt in the sea may be only one “evidence” for a young earth, but it is far from unique. Most of the “evidences” are vague at best about exactly what upper limit they place on the age of the earth, and in some cases don’t place any upper limit on the age of the earth at all. On the other hand, old-earth studies tend to be high precision, and the limits they place on the ages of the samples that they test are tight. The underlying assumptions are very, very reliable, for the simple reason that…

10. Accelerated nuclear decay is science fiction.

Perhaps the most outlandish claim that I’ve ever seen coming from the young earth movement is the RATE project’s hypothesis that nuclear decay rates must have been a billion times higher at certain points in the past six thousand years: notably during the first two days of Creation Week and during Noah’s Flood.

What makes this one so outlandish is that they themselves admitted that this would have released enough heat to raise the temperature of the earth’s surface to 22,000˚C — nearly four times that of the surface of the sun. Not only would there have been no Flood left, there would have been nothing left to be flooded!

On top of that, they acknowledged that no known thermodynamic process could have removed this amount of heat fast enough, and that any cooling process would also have had to have cooled rocks such as granites much faster than water, otherwise the oceans would have frozen over.

You can read all this in chapter 10 of the RATE project’s technical report, on pages 758-765.

The RATE team’s ability to downplay the seriousness of this problem is astonishing. Despite their own admission of an impasse of extraordinary proportions, the project has been portrayed as a success, with conferences, books and videos hailing it as providing conclusive evidence for a young earth, and accelerated nuclear decay being presented in their rebuttals of radiometric dating as if it were a proven fact. Randy Isaac of the American Scientific Affiliation (the US equivalent of Christians in Science) describes this portrayal as dishonest, and it’s not hard to see why.

Scientists do not blindly assume that radioactive decay rates are constant. Evidence for this comes from several different directions, not least the numerous cross-checks that are regularly done between radiometric dating and non-radiometric methods such as ice cores, lake varves, tree rings, Milankovitch cycles, and a whole lot more.

In any case, accelerated nuclear decay is the kind of discovery that would win a Nobel Prize if it could be shown to have any merit. Claims of this nature need to be supported by an extraordinary amount of evidence. A single set of studies by a single team working with a predefined agenda, that have never been replicated or even published in a mainstream peer reviewed journal, simply isn’t anywhere near sufficient.


For anyone wishing to discuss science and faith, there are plenty of interesting points for discussion out there, such as the apparent fine tuning that’s evident in the universe. The fact too that there are many questions about physics to which we don’t have the answers should also give us pause for thought, and perhaps instil humility in us as we marvel at God’s creation. But we don’t do ourselves any favours by claiming that scientists don’t know things that they do, or that they are just making things up when they are not, or that they are always changing their minds when they are not, or that they can’t test their assumptions when they can. Nor do we do ourselves any favours by getting all gung-ho and rushing headlong into the debate with all guns blazing only to prove that we haven’t a clue what we are talking about. Proverbs 19:2 says, “It is not good to have zeal without knowledge, nor to be hasty and miss the way.” In our discussions about these matters, let us be wise as serpents and innocent as doves.