GST 2420: Atoms and Stars
An Historical Introduction to Astronomy, Physics, and Scientific Discovery.
Fall 2002, Section 983, Call Number 16050
Agenda 14 for 12/11

  1. Announcements:
    1. Final is next week, 12/18. This week is the last regular class.
    2. Lab tonight is V. There will be time in class to complete the writeup for that lab, so that you will have only the Final to worry about during the week before the Final.
    3. I have emailed a test message, to see if I have eneryone's correct email address, for notification when I have posted final course grades on the online grade reports. If you do not receive the test email, let me know.
    4. Course web site: http://www.cll.wayne.edu/isp/drbowen/aasf02 (also links from Pipeline).
    5. Online Life at WSU with links at http://www.cll.wayne.edu/isp/drbowen/OnlineLife.
    6. Online grade reports were probably not working for a couple of days last week (passwords rejected) are working now.
      1. There may be glitches with the University online grade reporting system (yes, it COULD happen, unlikely as it may seem). In the past, employers have accepted printouts of the above type of course grade report.
    7. From what I have seen, the State of Michigan budget cuts will not affect the availability of classes.
  2. Essay 2 comments.
    1. Many people picked up the statement in Nissani's essay that science does not say why the Laws/Theories are true. I want to remind you that I said that this is not actually correct. Often, explanations for laws are provided later. This has to do with my idea of spreading blobs of known facts. The outer layers come later, and often explain the inner layers that were used to discover them. For example, Newton's Laws explain Kepler's Laws. In turn, Newton's Laws are explained by Relativity, and perhaps also by the idea of the exchange of "gravitons," although gravitons have not actually been observed yet. Relativity explains Newton's Law of Universal Gravitation by saying that the gravitational force is caused by the bending of space-time in the vicinity of a mass. Spinning a marble around in that funnel is a very good analogy here. Also, other forces (electromagnetic, nuclear and weak) are known to be caused by the exchange of "field particles." These are photons in the the case of the electromagnetic force, pi and other mesons in the case of the nuclear force, and the W meson in the case of the weak force. Quantum Electromagnetism, the theory that explains the electromagnetic force as due to the exchange of photons between charged particles, is often called the most precisely confirmed theory of all. Another example of an "inner" theory being explained by an "outer" one is the explanation of the Second Law of Thermodynamics (heat always flows from hot to cold, or energy always degrades towards an unusable form) by Boltzmann's and Gibbs's Statistical Mecahnics; energy runs downhill because there are many more ways for this to happen than for energy to run uphill from an unusable to a usable form. "Many more ways" requires advanced mathematics to understand, or at no one has come up with a good non-mathematical way to describe it (yet). Now, the outer layer, it is true, remains unexplained. But it is not a true statement that science never explains its theories. But let me ask you - is there ever an explanation of this type? Could there be an explanation of this type? That is, is it possible ever to have an explanation that itself requires no explanation?
    2. "Law" becomes "Theory."  The use of "Theory" replaced the use of "Law" in the twentieth century as scientists saw their "Laws" being overturned. But still, a scientific Theory is much more than a hypothesis, or guess. Many Laws were "grandfathered in," however, even if we now know the Law is not exact. It is still "Newton's Law of Universal Gravitation," even though we now know that, if Mass A moves as it exerts a gravitational force on Mass B, the change in direction of the force on B cannot be transmitted instantaneously, since nothing can travel faster than the speed of light. Thus, the direction of the force on B always points a little behind A. This is the cause of the advance of the perihelion of Mercury.
    3. Several people mentioned that the type of evidence is different for different areas of science. For physics, chemistry and biology, repeatable laboratory experiments can be done and are the standard. However, in astronomy we cannot wheel different planets into a lab to see what would happen if we did this. Similarly, in geology, we cannot say, "Let's experiment with a square earth." History is often counted as a science, and here we cannot say, "Let's see what would happen if Napolean had beaten those Russians." We can speculate, but we cannot experiment and know. This, of necessity, means that science will be different in these area. Some have used this to criticize the theory of evolution, saying, "It is not a real science because we cannot experiment with humans and dinosaurs competing with each other." One thing that happens is showing that results in these large-scale sciences can be derived or follow from the theories in the laboratory sciences. We can also look for traces of past events, and for consistency across the large body of specific observed facts.
    4. Science is not, probably never has been, and probably never will be, 100% internally consistent. The inconsistencies are generally at the frontiers, or the edges of the expanding blobs. For example, we believe both Relativity and Quantum Mechanics are true at the same time, and yet we cannot at this time make the two theories consistent with each other. And another hypothesis, Mach's Principle, which asserts that inertia exists because of interactions with the other masses in the universe, has been around for over one hundred years, is of great interest, and yet still can neither be proven nor disproven. And finally, many scientists understand that theories are never proven, they are just shown to be consistent with many experiments, and to have made significant predictions and so on, and yet we will still speak of theories being proven, as I just did.
    5. Many people made the point that the scientific method is basically common sense. But science has gotten far far away from common sense. I am not writing this as a criticism, but it is true. The earth turns. The world is made up of invisible atoms. Stars bend the space and time around them. What is going on? How can a method based in common sense take us away from common sense? The answer, according to Rachard Feynman, in The Character of Physical Law, is that science is a way of extending our common sense (like a lever?) outside of our common experience, into areas such as the very large, the very small, and the very fast, where we have no everyday experience. (If you're good, I'll tell you my Feynman story about the investigation of the Challenger tragedy.)
  3. Discussion of reading - Kansas School Board and Evolution etc.
    1. Creationism, Creation Science and Intelligent Design
    2. The nature of the Theory of Evolution.
      1. Survival of the fittest, but the fittest in the sense of leaving the most offspring which reproduce. Organisms must adapt to changes in the environment.
      2. Relative fitness is determined by genes which lead to adaptation. The genes must exist before the adaptation is required. This is a completely statistical process, with no pre-adaptation or foreknowledge. (Humans primarily adapt through culture today, which can pre-adapt.)
      3. In the 19th century, Jean-Baptiste, chevalier de Lamarck ("Lamarck") believed that characteristics acquired during an organism's lifetime could be inherited. Examples of acquired characteristics are a broken arm, or surgically enhanced body parts, or an education. But genes are present at the very start of the lifetime, and do not change due to acquired characteristics. (Genes can, however, mutate during a lifetime, and the mutations are passed on.)
      4. Trofim Denisovich Lysenko (Russian biologist under Stalin) believed that organisms could learn to adapt by being exposed, in line with Lamarck. "By 1948, when education and research in standard genetics were virtually outlawed, some geneticists had suffered secret arrest and death of undisclosed causes." (Encyclopedia Britannica 2002 CD-ROM.) Lysenko's policies lead to famines in Russia, and the loss of a generation or more of progress in Biology and Agriculture.
    3. What exactly was decided?
    4. How are the affected subject areas related?
    5. Decision reversed by election of new candidates for School Board on August 1 2000, one year after the initial decision
  4. Colliding circles of knowledge, relationship between science and technology
    1. Third example from this course: Newton uniting celestial and terrestrial mechanics. What was the "bonus?" A framework for the next 200 years - find those force laws!
    2. Will science continue as it has?
      1. Less interest in school
      2. Religious fundamentalism - moves towards creationism or intelligent design continue
      3. Increasing interest in mystical thought
      4. Decreasing government funding, increasing role of proprietary research - can science be science in a proprietary setting?
      5. Increasing (?) post-modernist attacks on science as just another belief system
      6. Possible limitation of science to industrial society, while we are moving beyond industrial society
      7. Less interest in a common social enterprise, less willingness in compromising to achieve it
      8. etc.
    3. Will there be consequences if science does not continue as it has? Some possible consequences: US leadership, economic, progress
    4. As science drives technology, the success of technology becomes additional evidence for the success of science (Nissani essay).
    5. On the other hand, I foresee science, in the next few decades, being able to explain who we humans are, and why we think and feel the way we do. Those who say that science cannot explain faith or ethics may be in for a controversial period. Those expanding circles of fact may expand further, into areas that people thought they could not go.
  5. Global warming from the early elements C, H, O, N.
    1. Fossil fuels are C and H, air is O and N. C and 2 O's combine to give CO2, carbon dioxide, H and O combine to give H2O, water. Everything else, such as N and O forming NO2, is a poison or severely degrades the environment. But CO2 is a greenhouse gas, traps heat in atmosphere, warms up the earth. Sunlight and heat radiation (infrared) are both electromagnetic radiation, but light can penetrate the atmosphere, while infrared (given off by warm objects) cannot, and gets reflected back to earth.
    2. Facts:
      1. CO2 will act as a greenhouse gas. (Interesting aside. Everybody assumes that H2O is benign, but clouds do have a warming effect.)
      2. The earth is warming.
      3. We are putting enough CO2 into the atmosphere to have an effect.
      4. Strong scientific consensus that man-made CO2 is causing the warming. There is a serious question about how much heating is going on.
    3. If second and third world industrialize to our level (and it is their announced intention to do this, and our announced intention to help them do it), then levels of CO2 will rise to six times current levels.
    4. Can we let it happen and adapt? My take on this.
      1. We know enough about the physical world to know that significant warming will occur.
      2. We do not know enough about biological world to predict what the effects will be, but there will be many.
      3. Also, we do not know enough about our society, including our economy, to predict what those effects will be.
      4. Therefore, we cannot make a rational decision about this, since we do not know how much it will cost to adapt.
    5. Possible effects (not an exhaustive list)
      1. Rising sea levels (sinking of island nations), tainting of coastal fresh water supplies, loss of land area.
      2. Generally warmer weather but with large regional and perhaps local differences, and increasing unpredictability and weather extremes. General increase in cloudiness, rainfall, and violent storms.
      3. Rising levels of CO2 lead to increased plant growth, but mix of species will change because of climate and weather. Some areas will probably benefit, among them Michigan, but this is not reliable since we don't know all of the effects, or their sizes.
      4. Possible increase in degenerative diseases such as bone spurs
      5. Possible increase in the activity levels of microorganisms such as germs, viruses, and soil organisms, and pests
      6. Loss of important ecosystems such as coral reefs and coastal marshes, credited with being the breeding grounds for much of our wildlife
      7. Possibilities for civil and economic disruptions
  6. Final exam
    1. Updated list of questions for final (handout)
    2. Draft of info sheet for Final (handout)
    3. Continue review.
  7. Lab V, pages 16 - 20.