[LINK] electromagnetic fields effect brain activity

Alan L Tyree alan at austlii.edu.au
Sat Jan 13 08:50:19 AEDT 2007

On Fri, 12 Jan 2007 16:31:41 +1100
Antony Barry <tony at tony-barry.emu.id.au> wrote:

> On 09/01/2007, at 12:47 PM, Alan L Tyree wrote:
> > Am I the only one here old enough to remember the Club of Rome?
> Yes. I read their report in draft and commented on it suggesting
> that they should transfer the demand for oil to coal when the oil ran
> out. as a consequence they cut their figure for the lifetime of coal  
> reserves.
> > Of
> > course, those weren't scientific tests, they were computer models.  
> > Like
> > most of the "scientific" predictions of today.
> ALL mathematical based theories are models. Also as soon as you get  
> away from anything trivial there are no exact analytic solutions and  
> you have to go to numerical approximations. This means computers for  
> anything other than the extremely simple. Then to top it all off any  
> set of equations which aren't dead simple are chaotic and after a  
> period of time the prediction will rapidly drift away from what the  
> real world does because of the impossibility of pinning down the  
> initial conditions. The key is doing a sensitivity analysis to have
> a handle on what the likely time into the future the prediction will  
> hold.  Even planetary dynamics are chaotic over a sufficiently long  
> timescale.

I agree with this. However, useful models can be, and are, testable and
tested. The problem with the models used in climate prediction and in
the Club of Rome models is that they either are not testable (like the
Club of Rome) or not tested (like many climate models) or tested and
the results of the testing ignored (like the many climate models that
cannot "predict" the 30 year global cooling of 1940 - 1970).

The Club of Rome models were essentially Malthusian: linear equations
to describe resources, exponential equations to define demand. Results
are exactly what were expected - and by adjusting the parameters you
can account for being off by a few decades or a few centuries.

> The Club of Rome said we could be in strife through a resource  
> crisis, a food crisis or a pollution crisis around the end of the  
> century depending what we did. They checked the sensitivity of the  
> prediction with respect to resources and showed that a doubling(?)
> of reserves just moved the problem back a decade or two because of
> the nature of exponential growth. They refined the model twice since.

Again, with the basic equation structure, doubling, tripling,
you-name-it increase in resources will merely shift the problem.

Any real-world description is going to be modelled by sets of
non-linear differential equations with lots of feedback. Since it is
hard to get a stable set of equations, most models are going to predict

Example: bombs are modelled mathematically by equations which describe
ovens!! These are good models that allow us to learn a lot, but it
should not come as a surprise that ovens do not blow up.

My own view is that we should be very skeptical of any model that
cannot predict the past. Further, it is not usually reasonable to adopt
the "precautionary" view of preparing for the worst. To do so is to
condemn millions of (mostly) third world people to a life of degrading

Time for me to go back to work.


> Donella H Meadows, Dennis L Meadows and Jørgen Randers. "Beyond the  
> limits: global collapse or a sustainable future". Earthscan, 1992
> Donella Meadows, Jørgen Randers and Dennis Meadows. "Limits to  
> growth; the 30-year update". Earthscan, 2005.
> Their conclusions overall haven't changed. The timeline has shifted  
> back a few decades not unexpectedly and there is trouble coming a
> few decades ahead. Depending what we do it will be very nasty or
> only somewhat unpleasant for a time.
> Look where we are at now -
> Resources
> ---------
> Crude oil production will probably peak by 2015 and then start to  
> decline with natural gas not to far behind.
> For many metals we are going to lower and lower quality ores.
> Pollution
> ---------
> Global warming
> Rapidly increasing dead zones in the oceans
> Ozone hole not decreasing as expected
> Inexplicable rise in cancers in the developed world
> Food
> ----
> Soil depletion
> Rapid fall in the water tables in key grain growing areas which rely  
> on ground water
> Per capita grain reserves lowest for 35 years
> Loss of crude oil will impact heavily on the green revolution
> The crunch is coming.
> If anybody wants to discuss this could we shift it to unlink.
> While I write this it is 40.8 degrees in my part of Canberra so I'm  
> feeling a bit crabby. It was over 40 yesterday but there is a change  
> coming although the storms appear to have gone to the south of us.
> Tony
> phone : 02 6241 7659 | mailto:me at Tony-Barry.emu.id.au
> mobile: 04 1242 0397 | mailto:tony.barry at alianet.alia.org.au
> http://tony-barry.emu.id.au

Alan L Tyree                    http://www2.austlii.edu.au/~alan
Tel: +61 2 4782 2670            Mobile: +61 427 486 206
Fax: +61 2 4782 7092            FWD: 615662

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