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Accelerated Radioactive Decay

alpha_decay — One mode of radioactive decay is alpha decay, where an unstable nucleus spits out two protons and two neutrons bound together as a helium nucleus, which is also called an alpha particle.
(public domain image)

When I first heard about the idea that radioactive decay might vary from the smooth, constant-half-life behavior that is typically observed, I was more than a little skeptical. As a nuclear chemist, I am well aware of how much energy it takes to affect nuclear processes. Since those energies are not generally attainable except with the use of a particle accelerator, a magnetic containment system, or some other high-powered device, it seemed absurd to think that variable radioactive decay was anything other than the mad wish of those who didn’t like the conclusions of radiometric dating. However, over the years, the data have convinced me otherwise. I written a couple of posts about variable radioactive decay (see here and here), and it seems clear to me that it does happen, at least under some circumstances.

Recently, I came across another study on variable radioactive decay. It is actually a follow-up to a previous study,¹, and it explores the alpha decay of uranium-232. As shown in the drawing above, alpha decay is one specific type of radioactive decay in which an unstable nucleus attempts to reach stability by spitting out two protons and two neutrons. Those four particles are bound together to form the nucleus of a helium atom, which for historical reasons is also called an alpha particle. It turns out that when uranium-232 does this, the resulting nucleus still isn’t stable, so a long series of further alpha decays occur, eventually producing lead-208, which is stable.

The authors of the study I am writing about weren’t interested in the subsequent decays. They looked specifically at the alpha decay of uranium-232. Under normal circumstances, this decay has a half-life of 69 years.^* This means if I start with 200 uranium-232 atoms, after 69 years, only half of them (100) will remain. The other half will have decayed away. If I wait another 69 years, only half of those (50) will remain. In another 69 years, half of those (25) will remain. In the end, this is typically how radioactive decay works: the number of radioactive atoms ends up decreasing by half over every half-life.

The results of the study seem to indicate that a tabletop device involving a laser and gold can end up decreasing the half-life of uranium-232 by as much as a factor of 435,494,880,000,000!²

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An Insect with Gears

The video above shows you the jumping prowess of a juvenile Issus coleoptratus, a species of plant hopper. As its name implies, this insect hops from plant to plant, eating sugar directly from the veins of the plant’s leaves. Believe it or not, jumping is a rather difficult way to travel, because once you are in the air, you don’t have a lot of control over your body’s movement. As a result, the jump itself is very important. Not only must it be aimed correctly, it must happen so that the body stays upright throughout the time it is in the air.

That latter task can be a bit difficult. Imagine, for example, if an insect pushes off really hard with one leg, but not very hard with the other leg. This imbalance would cause the body to start spinning in the air, which would make for horrible aerodynamics and a very difficult landing! The same thing would happen if the pushes were not timed very well between the legs. If one leg started pushing sooner than the other, the insect would once again go spinning out of control. Most jumping insects are designed to deal with this by having their jumping legs arranged on either side of the body. This gives them a larger margin of error when it comes to both the timing and the force of each leg. This is convenient, but it also inherently limits how high and far the insects can jump.

For species of insects that must jump really high and far, the legs must be right under the body. This maximizes the amount of force that goes into the jumping motion, but it also allows for only a tiny margin of error in terms of the timing and relative force of each leg. As a result, these species must coordinate their jumping legs very, very precisely.

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Relationships in Nature Go Deep – Really Deep!

It has long been known that the species of jewel wasp pictured above (Nasonia vitripennis) can mate with another species of jewel wasp (N. giraulti), but the male offspring die in their larval stage. This, of course, keeps the species separate. Scientists have always assumed that the death of the male larvae must have something to do with an incompatibility between the two species at the genetic level. However, a recent study indicates that’s not true. The real reason the males die off is because their bacteria are incompatible with them.

Each species has bacteria living in its gut, helping it digest food, fight off infection, etc. However, the actual mix of bacterial species is different in each wasp species. When male larvae that came from the interbreeding of the two species were given antibiotics to kill off those bacteria, the larvae were able to survive. They weren’t incredibly healthy, but they were as healthy as purebred wasps that also had no bacteria living inside them. However, when bacteria from either species were introduced back into the larvae that came from interbreeding, they died! In the end, then, the males don’t die because of genetic incompatibilities. They die because of bacterial incompatibilities. As ant taxonomist Dr. Corrie Moreau commented:¹

I would never have predicted that…We were blown away.

So in some way that we don’t currently understand, the bacteria that live in the gut of these two species of jewel wasps so fundamentally affect their development that the wasps cannot survive unless they are compatible with a specific mix of bacteria. Interestingly enough, this isn’t the only case of bacteria affecting the development of an animal.

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Another Experiment from Science in the Beginning

As if I have not been harping on this enough, I have a new book out. It’s called Science in the Beginning, and it’s an elementary science course that uses the days of creation as reported in Genesis to introduce scientific concepts. The course is very hands-on, with an experiment or activity in every lesson. One of the homeschooled students who field-tested the course, Ryan McFall, has been kind enough to allow me to show pictures that were taken while he was performing some of those experiments. This one is about diffusion.

First, soak an egg in vinegar for a day or so:

The vinegar will slowly react with the calcium carbonate shell of the egg, turning it into a salt (which dissolves in water) and a gas (which bubbles away). In the end, you are left with an egg that has no shell:

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The Atomic Bomb and the Brain

One of the features of the mammalian brain is a structure called the hippocampus. Since the brain is split in half, every mammal has two hippocampi, one on each side, as illustrated in the drawings of the human brain above. These structures are very important for the formation of memories as well as spatial navigation. The reason I am telling you all this is because an incredibly interesting study was just published in the journal Cell, and it uses the aftereffects of the atomic bombs (both their use and testing) to pin down the specifics of how many new brain cells people make in their hippocampi throughout their adult life.

At one time, it was considered a rather strong scientific fact that adult mammals do not produce new neurons (the cells that make up the basic building blocks of the nervous system). For example, An Introduction to Neural Networks (a textbook published in 1995) puts it this way:¹

In mammals, although not in many other vertebrates, central nervous system neurons have an important peculiarity; they do not divide after a time roughly coinciding with birth. When a neuron dies, it is not replaced.

Prentice-Hall’s textbook, Exploring Life Science (published in 1997), tells us what this means for people:²

All the neurons you will ever have were formed by the time you were six months old.

We now know that such statements are incorrect. In a variety of mammals that have been studied, adults produce new neurons in the olfactory bulb (a part of the brain used in the sense of smell) and the hippocampus.³ This new study uses a technique that shows adult humans produce a significant number of new neurons in their hippocampi, but they probably don’t produce new neurons in their olfactory bulbs.

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Richard Dawkins Produces Another Theist

Dr. Laura Keynes grew up in Cambridge, arguably the intellectual center of the United Kingdom. She studied at the University College of Oxford on a full-ride scholarship and ended up earning a Doctor of Philosophy degree. Her doctoral thesis was on epistemology, the study of knowledge and justified belief. As her last name indicates, she is the great-grandniece of the famous economist John Maynard Keynes. She is also the great-great-great-granddaughter of Charles Darwin.

Why am I telling you about this young lady? Because she recently wrote an article entitled, “I’m a Direct Descendant of Darwin…and a Catholic.” Now the title didn’t surprise me at all. I know a lot of Catholics (and even more Protestants) who believe in evolution. Indeed, one of the leaders of the Intelligent Design movement, Dr. Michael Behe, says:¹

You can be a good Catholic and believe in Darwinism. Biochemistry has made it increasingly difficult, however, to be a thoughtful scientist and believe in it.

However, as I read the article, I couldn’t help but smile. You see, Laura was raised Catholic but drifted away from the faith after her mother became a Buddhist and her brother rejected all organized religion. By the time she was studying for her Doctor of Philosophy degree, she was an agnostic. During that time, however, Richard Dawkins had opened up an international dialogue on the existence of God with his thoroughly awful book, The God Delusion. Well, Laura decided to read Dawkins and his fellow New Atheists, and she says:

I expected to be moved from agnosticism to atheism by their arguments, but after reading on both sides of the debate, I couldn’t dismiss a compelling intellectual case for faith. As for being good without God, I’d tried and didn’t get very far. At some point, life will bring you to your knees, and no act of will is enough in that situation. Surrendering and asking for grace is the logical human response.

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An Experiment From My New Book

I have been posting a couple of videos of me doing experiments from my new book, Science in the Beginning. You can find them at the publisher’s YouTube channel. However, one of the Australian mothers who field-tested my book, Jen McFall, posted on her Facebook page some pictures of her son, Ryan, doing a few of the experiments. She has graciously allowed me to use the pictures to show other people how much fun the experiments can be. Here is one about how light can do multiple things when it encounters a new substance:

Step 1: Fill a glass bowl with water:

Step 2: Lay a utensil (like a spoon) on the bottom of the bowl:

Step 3: Arrange the bowl so it is at the edge of a counter, and then look up through the side of the bowl:

Notice that you see the spoon lying on the bottom of the bowl, but you also see an image of the spoon upside down on the surface of the water! This is because when light encounters a new substance, it can do more than one thing. You see the spoon lying at the bottom of the bowl because light passes through the bowl, passes through the water, reflects off the spoon, passes back through the water, passes back through the bowl, and travels through the air to hit your eyes.

You see the image of the spoon upside down on the surface of the water because light passes through the surface of the water, travels through the water, reflects off the spoon, travels back through the water, reflects off the air at the surface of the water, travels back through the water, passes through the bowl, and then travels through the air to hit your eyes. Nevertheless, when you look straight down into the bowl, you can see the spoon lying there (see step 2). That’s because some of the light passes through the surface of the water, travels through the water, reflects off the spoon, travels back through the water, and passes back into the air so it can travel through the air and hit your eyes.

So in the experiment, you see that when light hits the surface of the water after reflecting off the spoon, it can do two things. (1) Some of it passes back into the air, which is why you see the spoon lying at the bottom of the bowl when you look down at the bowl from above. (2) Some of it reflects off the air so you can see the upside-down image of the spoon when you look through the side of the bowl from below.

People Weren’t The First to Develop an Internet!

mycorrhizae1 — This microscope image shows an arbuscular mycorrhizal fungus in a clover plant's roots.
(Click for credit.)

The microscope picture above shows you a clover root (the mostly transparent material in the picture) whose cells have been “infected” with a fungus (the thick, dark material in the picture). At first glance, you might think the fungus is a parasite that takes nutrients from the plant, but that’s not really true. While the fungus does take nutrients from the clover, it also supplies the plant with critical nitrogen- and phosphorus-based chemicals that the plant has a hard time extracting from the soil. This is a mutually-beneficial relationship, which is often called a mutualistic relationship.

As anyone who has read this blog for a while knows, I am fascinated by such relationships. I have blogged about them many, many times before (see here, here, here, here, here, and here, for example). In fact, I have blogged about this specific kind of mutualistic relastionship before. It is called a mycorrhiza, and it is very, very common in nature.

About 95% of all vascular plants develop mycorrhizae,¹ and these relationships come in many different forms. For example, in the relationship shown above, the fungus forms a highly-branched structure called an arbuscule, which comes from the Latin word arbusculum, which means for “little tree.” This arbuscule is formed inside the walls of the root’s cells, and the fungus is called an arbuscular mycorrhizal (AM) fungus. Such fungi cannot exist by themselves. They can only exist as a part of a mycorrhizal relationship. There are other forms of mycorrhizae as well, but the study I want to discuss is specifically about AM fungi.

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The Blue Planet

Astronomers call earth “the blue planet,” because when you look at it from space, it often appears blue. That’s because most of the earth is covered with water, which reflects blue light better than the other colors of light. So when white light from the sun hits the earth, more blue light is reflected than any other color (as long as there isn’t an enormous amount of cloud cover).

The Cassini space probe that is currently in orbit around Saturn recently had a chance to photograph the earth. It appears as the tiny blue dot pointed out in the photo above. Please click on the photo to get the full-sized version. It really is magnificent. At the time the photo was taken, the earth was 898 million miles away from the Cassini space probe. Nevertheless, it appears as a vivid blue dot on a mostly dark background. In addition, if you “zoom” in close enough, you can actually see the moon orbiting the earth:

cassini1 — The earth (left) and moon as seen from 898 million miles away.
(Credit: NASA/JPL-Caltech/Space Science Institute) Click for a full-sized version.

Notice the differences between the earth and the moon. The moon is smaller, but more strikingly, it appears a stark white next to earth’s blue.

The earth has been intricately designed as a haven for life. Its blue color is a beacon proclaiming that, and the beacon can be seen from nearly 900 million miles away!

More Evidence That Earth Is Designed to Resist Warming

The earth’s polar regions have large amounts of permafrost, a thick layer of soil underground that stays frozen throughout the year. It has been suggested by climate alarmists that as the earth warms, this permafrost will begin to melt, and that will lead to disastrous consequences. Why? Well, there is a lot of organic material in this permafrost, and it doesn’t decompose much, because decomposition is slowed significantly due to the soil being frozen. As the permafrost thaws, decomposition will increase, and that will lead to a significant amount of carbon dioxide and methane being released into the atmosphere. The release of these greenhouse gases, of course, will further accelerate global warming. This affect is known as the permafrost carbon feedback, and here is what the United Nations Environment Programme says about it:¹

If the permafrost thaws, the organic material will also thaw and begin to decay, releasing CO2 and methane into the atmosphere and amplifying the warming due to anthropogenic greenhouse gas emissions…The permafrost carbon feedback is irreversible on human time scales. Warmer conditions and increased atmospheric CO2 will enhance plant growth that will remove CO2 from the atmosphere, but this can only to a small degree compensate for the much greater carbon emissions from thawing permafrost.

Notice how strongly this is worded. The effect is “irreversible,” and even though a warmer climate will result in more plant growth, this will not come close to offsetting the devastating amount of greenhouse gases released by the thawing permafrost.

Well, the results of a 20-year experiment have been published in the journal Nature, and not surprisingly, they show that the effect is precisely opposite of the nonsense quoted above.

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