Entropy reversed

I had an ulterior motive when I wrote the last blog post. It was a needed lead-up to its final italicized statement:

If you pump energy into an isolated system, order will increase.

It 's easy to prove the opposite. Just be lazy for a while and don’t put energy into keeping your living space in order. Disorder [entropy] increases, and it can get really messy!

It isn’t so easy to do an objective experiment to prove that adding energy to an isolated system brings about order. However, I did read of a very convincing such test suggested by Dr. John Todd in his forward to Gaia’s Garden, a book by Toby Hemenway. I was so impressed, in fact, that I have described it below and quoted Dr.Todd himself:

In teaching ecology classes Dr. Todd asked his students to collect samples of equal volume from at least three aquatic habitats, such as a small pool in the woods, an animal wallow on a farm, and a river- or lakeside marsh. They were then to mix them together in a glass jar until it was about half full, and with the jar’s lid screwed on tightly, turn it upside down and place it in a sunny window. They were then required to watch and record the unfolding drama within over a period of weeks.

Quoting Dr. Todd: “In the presence of sunlight, a microcosm, or miniature world, begins to organize itself. … Within days, an internal physical structure or architecture starts to evolve, complete with biological zones of activity. … The communities that adapt within are unique. … And each of the student’s microcosms develops differently. … If a blind is left closed and the sunlight blocked for several days the ecosystem within will collapse. But if the jar is returned to the light soon enough, the living system will begin to reorganize itself. The self-repair process generates a new system, usually different than the one from which it was derived … yet as a whole, the system is amazingly persistent. … The miniature ecosystem (on my desk) that I am looking into now as I write may well outlive me.”

Amazing? I rest my case that the reverse of the Second Law of Thermodynamics holds true. Rie

The Sun

Like a precious spring in the vast empty desert of space, the Sun makes our Earth a beautiful living oasis in the cold, dark universe around us.

What makes the Sun shine and keep on putting out such colossal amounts of energy for billions of years? It is amazing to me that, like most people, I didn’t ever ask that question when I was growing up. Maybe it was because the Sun is so awesome that I didn’t think anyone could possibly know the answer.

But Einstein figured it all out in 1905 when he developed his famous equation: E=mc²

That equation simply says that energy (E) and matter (m) are interchangeable -- one can be turned into the other. In the Sun, incredible amounts of energy (E) are created when very, very small amounts of matter (m) are destroyed. That’s because the constant (c²) that is on the same side of the equation as the mass (m) stands for the enormous speed of light multiplied by itself.

The Sun is made up of gases, about 75% hydrogen and 25% helium. In the very hot centre of the sun (15 million degrees Celsius), two hydrogen nuclei fuse when they collide, and the helium nucleus that forms as a result has a mass (m) that is very slightly less than the combined masses of the two hydrogens. That lost mass (m) is converted to the prodigious amount of energy (E) in the form of heat and light that the Sun gives off and has been giving off for billions of years. Watching this short YouTube clip helps visualize this thermonuclear reaction happening in the Sun.

So far the Sun has used up only about half its hydrogen, so no worries, there is no reason it won't keep flooding planet Earth every single day with an amount of energy that is equivalent to the whole of the world’s oil resources. That constant and beautiful supply of energy has been a major cause of the truly awe-inspiring evolution that has occurred on our planet – that, and of course the laws of nature.

One of nature's laws - the famous Second Law of Thermodynamics – says that in an isolated system, Entropy, or disorder, increases. But what about a system that is not isolated and that is receiving the wonderful energy from the Sun constantly? A relatively new theory, Complexity Theory, recognizes that if you pump energy into an isolated system, order will increase!!

Darwin certainly made great breakthroughs – recognizing evolutionary patterns and coming up with his ‘survival of the fittest’ dictum. But consider the tremendous driving force for the increasing complexity on the planet that is now being directed by us. And where do we get our energy? Indirectly, like everything else on Earth, from that marvelous thermonuclear reaction going on in the Sun! Rie

Chirality

As a break from our harsh Canadian winters we have ‘gone south’ to the Caribbean islands for years. I love beach combing and as a result, I have baskets full of sea shells at the cottage that I have picked up and enjoy handling.

When I read that spiral shells were a good example of the invisible chirality [left or right handedness] that many molecules in living systems possess, I lined up some of my spiral shells with their earliest growing tips down and took the picture above. When you look at the picture, you can’t help but see that the open ‘mouth’ of the shell is always on the left.

Try it out yourself the next time you have any spiral shells at hand, and you may be lucky enough to find a shell that breaks the rule and opens on the right. They are rare, but exceptions do exist, and therefore the shell's outward chirality must be for another reason, because our body’s chiral molecules are always only one-handed without exception! For snails, the reason for the shell coiling happens to be sex. Snails make coiled shells because their sexual organs are usually twisted, and it is difficult with snails of opposite handedness to mate. Picture on the right is the Nautilus shell.

The fact that our body’s DNA, enzyme and sugar molecules, etc., are chiral was not generally known until a widespread medical tragedy occurred. In the late 1950’s, a drug called ‘thalidomide’was developed by a pharmaceutical company as a sedative and a treatment for morning sickness in early pregnancy. When tested on animals it had few or no side effects, and so was used in many countries, including the UK and Canada starting in 1958. It was not until 1961 that doctors fully realized the drug was the cause of severe birth defects – many children developing flippers instead of arms.  It was withdrawn but too late for kids shown on the left .

When thalidomide was investigated, the results knocked organic chemists for a loop. It was discovered that the molecule was chiral, and when synthesized in the lab, equal amounts of two isomers, one left-handed and the other right-handed, were produced. Because molecules involved in our body chemistry are also chiral, the two isomers reacted differently, with one isomer causing the birth defects. Fortunately, under normal circumstances, if we ingest a molecule with the wrong handedness, our bodies recognize it and - unlike the unfortunate thalidomide case where a fetus was in an early stage of development - it is sent to the liver where most toxins are dealt with.

The development of one-handedness in our body chemistry probably happened just by chance when life first formed on our planet. Should we ever travel to another planet many light years away, it is possible that life started there with its molecules having the opposite handedness, and we could eat as much of their food as we wanted, but we would starve to death! Rie

Clouds

A few years ago we had a visit from a friend with a small plane, and when he invited me to go up with him, I jumped at the chance! It was my first time being in the co-pilot's seat, and the fun of the joy-ride for me was heightened by the number and variety of all the switches and dials on the instrument panel, but even more so by the routines and checks my now preoccupied companion was carrying out. I was fascinated with the flight plan he was reporting and the information he was jotting down that was coming from some voice of authority I could hear through his earphones.

It would have been inappropriate to interrupt any of these serious preparations, but I made a some mental notes and, after we successfully landed, I was ready with a few questions. One of them had to do with the dew point. I already knew that the dew point was the temperature at which water molecules slow down so much that they tend to stick to each other instead of bouncing off like they do when they are moving faster at higher temperatures. But why did the pilot need to know the dew point, and why was it reported as an altitude? It turned out that it was just another way of telling him the altitude at which the clouds started forming!

As air rises, it expands and cools down, so this means that at a certain height the temperature reaches the dew point and water vapour condenses. Simple enough - but ever since thinking about it like a pilot, I have taken special delight in looking at clouds. Understanding why they are so often flat lets you observe the normally invisible water vapour in the air appear all at once. The darkness on the bottom of flat clouds is another story for another time.

Just as I find a painting often lets me delight in seeing the world the way the artist was seeing it when he/she created it, so I think scientists can often give us information that allows us to take delight in observing from their informed perspective.

I hope that on a partly cloudy day after this you will find new appeal in looking at the clouds billowing above their flat bottoms. Rie