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Monday, 3 February 2020

Picture Post #53 Buckled Rails


'Because things don’t appear to be the known thing; they aren’t what they seemed to be neither will they become what they might appear to become.'

Posted by Thomas Scarborough

Buckled railway line near Glasgow, 25 June 2018.

The thermal expansion of railway lines is governed most simply by the formula

Δ L ≈ α L Δ T

This formula failed near Glasgow on 25 June 2018, when railway lines buckled in the heat. In fact they buckled in heatwaves all across Europe in the 2010s.  Why?  The answer is simple.  This formula, and versions of it, failed to include environmental factors—at least, not those which mattered.

It is not only railway lines which buckle.  Oceans are polluted, glaciers retreat, bees are poisoned, toads go blind, groundwater is poisoned, people suffocate—in fact, thousands if not millions of things go wrong besides—all without their being included in the formulae.

Here is the problem.  We take at face value that physical laws are true of this world.  It is the heresy of Plato.  Ordinary things, held Plato, imitate forms.  We hold up forms to reality, which is formulae: 'This is how it is!'  It is not.  And so the world is continually bedevilled by negative consequences.

6 comments:

Keith said...

‘Here is the problem. We take at face value that physical laws are true of this world. It is the heresy of Plato’. Let’s say, hypothetically, that our physical laws and their mathematical representations are flawed — untrue in some material manner. Aren’t these laws and formulas, if ‘untrue’, only that way by degree rather than in their entirety? Aren’t these laws and formulas — no matter their purported imperfections — still essential to us on at least some important level, even as workable approximations? Isn’t it possible to keep improving our physical laws and mathematics — additively, without necessarily canceling each other out — in ways that serve our needs, better and better? Besides, if, instead, we do dispose of these flawed — untrue — laws and formulas as a whole, what better means might be at our ready for learning about, understanding, and describing physical reality? (At a mundane level, to keep those rails from buckling in the future.)

Martin Cohen said...

I'm not sure the image conveys this grand failing, only the more obvious one of not being able to cope with unusual conditions. Indeed, as our blogger says, the "railway lines buckled in the heat"...

As an image, it is somehow rather sad, to me..

Thomas O. Scarborough said...

In reply to Keith. The railway formula in the post is probably the simplest one in use, derived from the more subtle dL ÷ dT = αL. There are expanded versions, too. However these did not predict the buckling of rails throughout the UK. Did we therefore make subjective decisions as to how much our formulae should include? Or worse, did we not think on this at all?

Take the internal combustion engine, which is basically governed by the formula 2C8H18 + 25O2 = 16CO2 + 18H2O. It took us 100 years to realise that this formula was too insular, to the extent that we now want to do away with combustion engines. The problem: we developed the formula in a closed system, but the world is an open system.

There are some very worrying things now. Take the algorithms that we use to improve the efficiency of commerce, gleaned from billions of devices such as yours and mine. The algorithms have an often rapid global impact. Do we understand what we have left out of these algorithms?

The bottom line is that we always fail to take reality into account. Even if we take a wooden ruler and measure an inch. That inch is ideal. The wooden ruler and the thing we measure are not. The fact that we call our formulae 'law', and so on, may deceive us greatly. Perhaps a solution would be to set the scientific method in a new context: an open system rather than closed systems.

Thomas O. Scarborough said...

But now, in reply to Martin, are we not at risk of undoing thousands of years of history? One could, for instance, wait for bits to fall off aircraft before we declare 'unusual conditions'. Have we not, over hundreds of years, learnt to think ahead, to forestall unusual conditions? The trouble is, we often don't. That in turn is the result, I propose, of subjective thinking. In the case of railway lines, we assume subjectively that certain environmental conditions will prevail. In the case of commerce, we assume subjectively that we aim for faster supply and demand. And so our formulae, our algorithms, theories and so on ride on top of subjective assumptions, and lead to such things as bucked rails (and so much more).

Tessa den Uyl said...

Thank you Thomas for this view on formulas and their unformulated sidetracks.

The picture with the two workmen also looks like a trick played by someone to disturb the usual mindset focused on expectations of functionality. The slightest irregularity evokes disfunctioning. And when I think of wagons, to make a train, is that not a bit like our mind? ...

Thomas O. Scarborough said...

Thank you, Tessa. Our minds do indeed snap-snap-snap words and concepts together, and that I think is the whole problem of modern (as opposed to postmodern) philosophy. Or as you say, it is much like linking wagons.

Further to Martin's comment, I stumbled upon a paper today by Nancy Frankenberry, 'Environmental ethics in neopragmatist hands would seek procedures for bringing about agreement in improving our practices, not our epistemology.' I suspect that Martin is the neopragmatist?

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