This year has been declared International Year of Physics. It's been 100 years since 1905, the year that Einstein signed these wondrous items that have become the history of science.
However, there is Einstein's work of what I write. I believe that there is enough information about Einstein, that will give us a lot this year, nor think that I can contribute much (although the year is very long and probably will finish writing something.)
This year, another anniversary occurs scientific, well connected, incidentally, another great German physicist. In this case, a geophysicist. Also part of the history of science. But, paradoxically, and without ever having come to understand it, is usually ignored in reports, books, articles ... the history of science. I am referring to the great geophysicist, meteorologist, climatologist, Berlin astronomer and polar explorer Alfred Wegener. Valga this article as my special tribute to the German scientist. It will serve as an excuse to start a series of 2 or 3 articles devoted to the vindication of a number of science, so convicted (in my opinion) as Wegener ostracism in the field of popular science and the media appreciation of science: Earth Sciences (and more specifically, of the Solid Earth).
Alfred Wegener, the magician of the obvious
Alfred Lothar Wegener
is one of those great examples that occasionally rewards us the history of science. Is an example of those great minds, which is attached a great curiosity and desire to learn, with a boundless capacity to assimilate ideas. One of those people who are able to hold his head encyclopedic knowledge, able to master many disciplines. When this is attached to a prodigious capacity for synthesis, we have the ideal mix for the emergence of revolutionary ideas. On occasion you can not remember, I heard a phrase that "a genius is a person who finds something that has been hidden, but a person who finds it clear that all we had before but we have not managed to do. " In this sense, Wegener was a genius. Spread knowledge gathered from different disciplines (the specialization of science, was beginning to impede communication between disciplines) and found the common idea that emerged from the combination of these ideas. That was Wegener, a magician of the obvious.
In this sense, Wegener is on the intellectual level of other "big" science. Just as Darwin had biology, physics had its Galileo, Newton, Einstien ... the Earth Sciences have had Wegener. Brief biography
Alfred Wegener Alfred Wegener
born in Berlin in November de1880. From a young age, he was attracted by Greenland, who became his passion. Study Natural Sciences and in 1904 he received his doctorate in astronomy at the University of Berlin. However, do not get to spend ever astronomy, tie in your career to the weather, which would make important contributions (making the use of balloons and studied the causes of rainfall).
's desire to become part of an expedition to Greenland was to train hard and become an athlete. Thus, in 1906, along his brother Kurt, beating the world record for staying in the air climbed to a balloon, remain in flight for 52 hours.
this year, in 1906, Wegener was invited to be part of an expedition to Greenland. On that expedition, Wegener became the first scientist to use balloons to study air movement in the atmosphere. Wegener became, well, a pioneer of meteorology.
In 1910, Wegener's hands comes a letter from the German naturalist von Hulmdot (1769-1859), which draws attention to the match between South American and African coasts. Let
a point to explain briefly the history of this idea.
Already in the seventeenth century, the English philosopher Francis Bacon had suggested the similarity between American and African coasts. Hulmdot
also noticed this similarity, but blamed on the Atlantic Ocean was a valley carved by erosion between America and Africa.
Lamarck (the same as evolution), intrigued by the fact that marine fossils can be found in inland areas, proposed a similar mechanism of "continental migration" to that proposed by Hulmdot. According to Lamarck, the erosion of the continents in specific areas, and deposition of erosion products in other areas, determine the migration of continents and oceans over time. In 1882 Fisher
Oswald related the migration of the continents with the formation of the moon from the Pacific. In the late nineteenth century geologist Eduard Suess proposed that all the southern continents had been united.
Back to Wegener.
Initially, Wegener saw this as a curiosity. But in 1911, when he was already a post as professor of meteorology at the University of Marberg, read a report which identified the paleontological similarities between South America and Africa. This is when you start to take the theory seriously and start working on it. Wegener
Simultaneously, and independently by two scientists American, Frank Taylor on the one hand, and Howard Baker on the other, they begin to develop the same idea.
In 1912, Wegener published his classic " On the origin of continents and oceans ." World War I prevented its spread, but when you hang issued new expanded editions, translated into several languages, putting his theory exposed to all the specialists of Earth Sciences.
geodynamics theory prevailing at that time meant that the distribution of continents and oceans had remained constant over geological time, and mountain ranges were formed to "wrinkle" Earth's surface due to the decrease in volume of the Earth since its formation by thermal contraction. Something similar to how an apple is wrinkled as the days and lose water. Wegener
What arose was that 200 million years ago, all the continents had been united into a large supercontinent called Pangea. And that this supercontinent was broken to make way for the current configuration of the earth's surface. This idea provided evidence other authors such as Alexander Steinmann and Gustav du Toit.
However, what was largely his theory of continental drift was critical. By the geology, where they found the more reluctance ideas for motorists was in the U.S. and Russia, not in Europe, where it had some support. In the U.S. the opposition came from an excessively over the principle of uniformity. In Russia, was linked to that prevailing ideas Tectonics and his disciple Tetyayev Beloussov. For tectonic Russian school, the only movements that took place in the earth's crust were vetical (in a way, this thinking is understandable, since it must be remembered that in the Siberian geology, for instance, a cratonic area, the cratons are old continental areas, dominated by vertical tectonics).
But it was the discipline of geology provided the strongest arguments against the ideas of Wegener. Rather, it was geophysics. Major geophysical events such as Harold Jeffreys Hans Cloos or strongly opposed to the theories of Wegener.
Here I have to make a clarification and take up the cudgels on behalf of these scientists. It is often said that the opposition by geophysicists Wegener's ideas came from what looked like an intruder, he was a meteorologist rather than an expert in the solid Earth. I do not think that way. Keep in mind that there were geologists and geophysicists at the time supported the German (du Toit, Arthur Holmes, Vening Meinesz, Argand ...). Told
thus history, it might seem that scientists are a dogmatic, clinging to their ideas even when they are indefensible, for fear of changing established truth.
really did not. These scientists, in order to accept the ideas of Wegener, needed a mechanism by which the continents moved. Failure to respond to that fundamental question, the theory was empty and left many more unanswered questions than answers. And Wegener was unable to propose any convincing mechanism. He suggested that the material they were made of continents was more rigid and less dense than the ocean, and moving like rafts over the denser material and viscous the oceans. However, he was unable to quantify or to suggest force capable of displacing (suggested two: the centrifugal force of rotation of the earth and tidal waves). This explains why
Harold Jeffreys (perhaps the most critical of the new winds blowing from Germany) strongly opposed.
was not until 1938 that Arthur Holmes propose a convincing mechanism, convection currents beneath the bark responsible for the movement of continents. This time supported by geophysical data, gravity data collected by the oceanographer Vening Meinesz.
However, in 1938 and Wegener was not to see it. Partly discouraged by the hostile receptions he had received his theory, and partly because he decided to focus on his passion, Greenland, left his studies of continental drift. In 1924 he wrote along the geographer, great student of the climate, Köppen the book " climate during geological times ." Since that year, served as professor of geophysics at the University of Graz in 1929 published the latest revision of its ideas, again and again to reveal its multifaceted nature and ability to relate ideas, while recognizing that failure to propose a responsible force was a major obstacle, followed vindicating their ideas, and was able to realize that there was a significant relationship between these forces of continental drift and all the processes of fracturing, seismicity, volcanism and changes in sea level (technically, eustatic ).
In the spring of 1930 he returned to Greenland, this time as leader of a scientific expedition that had about twenty members. In November (curiously the same birth month) for the same year, on this expedition, the great German scientist, was killed along with his frozen Rasmus coexpedicionario Willumsen, about 71 degrees latitude, having been heroically to provide supplies to a group of scientists who were isolated. Its bodies were found a year later. The story did not know it deserved honor: Wegener had no opportunity to see his theory consecrated.
In my opinion, there are many similarities between Wegener and Darwin. Both were two scientists who proposed revolutionary ideas that were characterized by their talent and ability to collect ideas from varied disciplines.
In the case of Darwin, he proposed his theory of evolution by natural selection acting on random variations, not directed. However, fundamentally, a mechanism that was able to explain the cause of these variations, it was something that conseguría Darwin.
Here is their similarity (Darwin luckier than Wegener, it must be said): either one or the other, were able to take ideas from varied disciplines, and recognize the evidence based on a surprising fact. However, they were unable to propose a convincing mechanism to explain this fact. The cause was that the two were ahead of their time. In the case of Darwin, had to wait 50 years for the emergence of genetics explicr allow the cause of the variations. For Wegener, it took about 40 years, as a result of the great campaigns of exploration and geophysical research, multidisciplinary and international, should meet a set of data that led to the advent of the modern theory of plate tectonics.
But what happened next?
After the death of Wegener, the fire is not extinguished. The burning wick he continued to burn, and were increasingly those who took seriously their ideas, and at the same time, there were frequent discussions between the two ideas.
We have said that in 1938 Holmes proposed a convincing mechanism. And there were ever more data, this time geophysicists, who supported the ideas for motorists. Meinesz gravimetric observations, studies of the magnetic pole moves along Runcorn times, Blackett and Irwin, the paleomagnetic measurements in the ocean (Mason, Piltman) or continent (such as Bolt), the studies on the ocean floor (by authors such as Dietz, Menard or Ewing), studies of the magnetic strip of the ocean, Fred Vine and Drummond Mathews ...
This, together with geological evidence, stratigraphic, paleontological and paleoclimatic, as pointed out by Wegener and others, was slowly brewing revolution. In 1962
Harry Hess proposed his theory of seafloor spreading, according to which in certain areas of the ocean, ridges , took place the creation of new ocean floor. In 1965, geophysicist Canadian J. Tuzo Wilson, who in 1959 rejected the theory of continental drift, in the paleomagnetic evidence develops, and publishes in Nature a model of continental drift, which has received the name "Wilson Cycle."
With all this, between 1967 and 1968, with authors such as McKenzie, Morgan, Parker or LePichon was born the theory of Global Tectonics or plate tectonics. This theory postulates that the outermost layer of the Earth, the crust , about 100 km thick, is divided into a series of blocks, plates calls that travel over the surface of the Earth following a movement angular can be described as a rotation around a fixed axis passing through the center of the Earth. The seismological work of Isaacs, Oliver and Sykes in 1968 corroborated the theory.
In 1929, Wegener wrote that the issue of the forces that moved the continents would be a problem that would last years. And he was right. Thus, we come to the 70s where we propose two different models (the Morgan and the Orowan-Elsasser) and are Forsith and Uyeda, 1975, the task of determining the forces acting on the surface of the Earth, deciding the debate in favor of the Orowan model. However, the details and more detailed questions about the movement of the crust are issues that still are discussed.
The most important lesson to be drawn from this story is that it could reach the explanation of all the evidence suggesting continental drift by integrating data from different disciplines. The theory of plate tectonics is a global theory. And as such stems from synthesizing data from all parts of the globe; data, moreover, of all types. Its acceptance comes as a result of the merger of previously separate disciplines (such as Geology, Geophysics and Oceanography). And its development comes from the introduction of data from geochemistry, petrology and the use of computers.
An important lesson: the key for multidisciplinary science. Quality which had Alfred Wegener to his credit.
We've gone from a theory geopoetry , as Harry Hess said in 1962, it established the prose of the current Global Tectonics.
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