View 637 august 23 - 29, 2010 (original) (raw)
Thursday, August 26, 2010
Musing on science
It continues hot in Los Angeles. There's a dinner tonight, and some other stuff so it's taking a while to catch up.
Meanwhile, one of the more interesting things to think about is the possible relationship of radiation decay rates to the Sun. From Rutherford's decrees on we have "known" that radiation decay rates are constant. For any given isotope there is a probability that it will decay and emit radiation. There are several kinds of radioactive decay. It's a bit more complicated now than it was when I was in high school physics, but the essentials are the same. The major kinds of radiation are alpha particles -- which are helium nuclei, two protons and two neutrons; beta decay, in which a neutron breaks up into a proton and an electron (and an anti-neutrino); and gamma decay in which things break up and emit x-rays. There are other kinds of radiation discovered more recently. In all cases, though, Rutherford's dictum was that the amount of radiation is dependent only on the number of atoms of the radiating stuff. Over time more atoms pop and do their emissions, so there are fewer of them left to pop, so the total radiation decreases.
We generally express this in "half life": the time it takes for half the radiation in a sample to be emitted, which is to say the time it takes for half the atoms to pop. There are a lot of theories on why a given atom pops when it does, but none I know of that "explains" it, and certainly none that will let you predict when a given atom will pop; that's a random process.
This is mostly confirmed by observation, but there are exceptions. Long term observations of the emissions of some substances like silicon-32 (half life 172 years) show something very strange: the radiation emitted certainly adds up to that expected by a half life of 172 years, but there is seasonal cycle, a wobble, with radioactive output peaking when the Earth is at perihelion and at minimum when the Earth is as aphelion. The closer we are to the Sun, the more radioactive output. The variation is fairly small, but it's there. There are observations of other periodic radiation, some in periods of 7 seconds. Since no one has been looking for any such thing, there's no predicting what else may be found on closer observation.
Understand that it's not easy to observe this. The variations are fairly small compared to the total radiation (which continues to conform to what's predicted by Rutherford's uniform decay rate if you look at longer time periods). You can't study this in stuff with half lives in the millions of years because the total decay is tiny and the variations would be invisible. It's hard to study it in stuff with short half lives because it doesn't last long enough to go through the cycles. You need stuff with half lives in the order of a century, it needs to be pure, and you need to look at it and record the output continuously. Until recently that hasn't much been done.
If proximity to the Sun affects radioactive decay, then presumably so does solar activity. A lot of the Earth's interior is radioactive stuff and its decay is what heats the Earth's interior. Apparently this is another possible coupling of the Sun to Earth temperature. How powerful this influence can be isn't known to me, and so far I haven't found anyone studying it. Perhaps it is not a large enough variation to put into the climate models. On the other hand, we know that climate seemed to be different during the Maunder Minimum (1645 - 1750) when there was very little solar activity (few to no sunspots). We don't have much of a sunspot count before that when the Little Ice Age was forming; but the Maunder Minimum happened during the middle of the Little Ice Age. In 1709 the Rhine froze and wasn't navigable until Summer. Many in Europe starved. After about 1715 sunspot counts rose, and so did temperatures. Whether that has any causal relationship is a matter of debate.
The acceptance of ignorance over what causes radioactive decay has annoyed a number of theoretical physicists. "It just happens that way" isn't very good theory, but our understanding of nuclear forces doesn't really give a better hypothesis. Attempts to quantify and understand nuclear forces including the "strong nuclear" force have resulted in a number of theories, and as I understand it are being revised again in terms of field theories. Let me hasten to say that my understanding is minimal. I wasn't all that interested in nuclear forces in my undergraduate physics courses. and the theory wasn't all that good in those days anyway. What I did learn was that we can't predict when a given atom will pop because we don't really know why it pops. I don't think that has changed much.
It does seem to me that if something as fundamental as nuclear decay can be influenced by solar radiation, this is a significant discovery. Whether it has implications for climate science I don't know, but since climate science has no real predictive power and doesn't seem able to explain things like the Ice Ages in any detail, it may be interesting. Ben Franklin postulated volcanoes shading the Earth could have great cooling effects and cause it to be cold. I'm not sure we have got a lot further than that, and I doubt that's the explanation for the 200,000 year Ice Age cycles. Note that we are in a temporary warm period in the middle of a big Ice Age. Our temporary warming period is about to run out; the best prediction from past cycles is that the ice will come back. That fear was all the rage when I first began writing science fact columns back in the last millennium.
The significance here is that the Rutherford dictum was about as accepted as anything in science ever can be. Now it appears to be in doubt. Science remains exciting, because there's so much we don't know -- but we could find out. If we keep looking.
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I have several messages critical of the Space Access Society because it doesn't want to abolish NASA. That seems naive. There is a case for public investment in space; the question is how that should be done. I have always been in favor of X=Projects and Prizes, both of which NASA can do. Space research facilities are expensive; NASA has them; we have a model of governent cooperation with airplane companies during the development of the aviation industry.
NASA has been a good part of the problem and the Standing Army has been one of the major factors; but NASA has done some wonders. It has good people as well as bureaucrats. I'd rather money went to NASA than the Department of Education. In 1980 Larry Niven and Art Dula wrote a paper called "How to Save Civilization and Make a Little Money" for the first Citizen's Advisory Council report. It got critiqued by everyone at the meeting and was rewritten and was part of the Council Report. It gave a good basis for a commercial space policy (Mr. Heinlein was one of those in attendance) and parts of that paper were incorporated into the Commercial Space Act. There are many ways that NASA can be of great benefit to the nation. We need real climate observation data. We need weather observations.
I've been one of NASA's most stringent critics -- I am told that when the rumor went around that I was going to be appointed Administrator there was sheer terror at NASA headquarters -- but I am no advocate of leaving research and development vital to the future of the human race entirely to commercial forces. It is the duty of government to look into the far future long past the time when you can predict return on investments.
I've explained all this in two papers; they are quite old, but the principles have not changed. SeeWhy Have NASA?, andHow To Get To Space.
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I found this interesting: http://news.cnet.com/8301-11128_3-
20014393-54.html?tag=nl.e703 It's a tour of the electric grid and I found it informative.
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Two moons on 27th August 2010
cid:1.183102900@web51001.mail.re2.yahoo.com
27th Aug the Whole World is waiting for......... ....
Planet Mars will be the brightest in the night sky starting August.
It will look as large as the full moon to the naked eye.
This will cultivate on Aug. 27 when Mars comes within
34.65M miles off earth. Be sure to watch the sky on
Aug. 27 12:30 am.
It will look like the earth has 2 moons.
(I suppose I ought to have explained: nothing can possibly be brighter than the full moon except the Sun. Mars doesn't get brighter than about magnitude -2.9, while Venus gets to about -4. The full Moon is about -13 at it's brightest. I don't know why included this other than whim. Please don't go out looking for two full moons...)
I think I must have been distracted by a phone call while I was looking for stuff to put up here and this didn't register.
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The newer GSM-based Kindles *do in fact* have a telephone number - that's how they work on the 3G network.
Go to a GSM-based Kindle's Settings screen, and then type '611' - you'll get all kinds of information (four pages of it), including the telephone number of the GSM Kindle.
You can try and register it on the MicroCell and see if it works . . . AT&T may disallow the phone number ranges they've allocated for the GSM Kindles, but it's worth a shot, if you've access to one of the newer GSM-based Kindles.
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Roland Dobbins
That I will have to try. Thanks!
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If this one doesn't bring tears, we are DEAD!
Click Here <http://www.youtube.com/watch_popup?v=KTb6qdPu8JE>
You may also find this interesting. The letter is at the link:
A Letter to President Obama
A link to Snopes (your favorite folks) -
Did a from nonagenarian World War II veteran write a letter criticizing President Obama?
snopes.com: Letter to President Obama - Harold Estes <http://shar.es/0boCA>
Ed
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A civil service workerproposes a corollary to the Iron Law.
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New Global Model for Climate Change Research Announced
"Scientists can now study climate change in far more detail with powerful new computer software released by the National Center for Atmospheric Research (NCAR) in Boulder, CO. The Community Earth System Model (CESM) will be one of the primary climate models used for the next assessment by the Intergovernmental Panel on Climate Change (IPCC)."
http://www.scientificcomputing.com/
news-DA-New-Global-Model-for-Climate-
Change-Research-082010.aspxThey say it takes a lot more things into account, and that the model itself will be freely available to all researchers worldwide. And they are trying to make the models match the actual data.
"Using the CESM, researchers now can simulate the interaction of marine ecosystems with greenhouse gases; the climatic influence of ozone, dust, and other atmospheric chemicals; the cycling of carbon through the atmosphere, oceans, and land surfaces; and the influence of greenhouse gases on the upper atmosphere. In addition, an entirely new representation of atmospheric processes in CESM will allow researchers to pursue a much wider variety of applications, including studies of air quality and biogeochemical feedback mechanisms."
I will be much interested in whatever comes of this. My expectations remain low.
And I have posted a lot of mailover in mail today.