Naturwissenschaften DOI 10.1007/s00114-005-0076-8 MINI-REVIEW Jesús Martínez-Frías . David Hochberg . Fernando Rull A review of the contributions of Albert Einstein to Earth Sciences—in commemoration of the World Year of Physics Received: 7 February 2005 / Accepted: 12 December 2005 # Springer-Verlag 2005 Abstract The World Year of Physics (2005) is an inter- Introduction national celebration to commemorate the 100th anniversary of Einstein’s “Annus Mirabilis.” The United Nations has In 1905, the same year that Albert Einstein obtained his officially declared 2005 as the International Year of doctorate after submitting his thesis (University of Zurich) Physics. However, the impact of Einstein’s ideas was not On a new determination of molecular dimensions, he pub- restricted to physics. Among numerous other disciplines, lished his five famous articles (Bushev 2000; Pais 1983; Einstein also made significant and specific contributions to Stachel 1998): On an heuristic viewpoint about the emer- Earth Sciences. His geosciences-related letters, comments, gence and conversion of light—submitted in March; A new and scientific articles are dispersed, not easily accessible, determination of the molecular dimensions—submitted in and are poorly known. The present review attempts to April; On the movement, required by the molecular theory integrate them as a tribute to Einstein in commemoration of of heat, of particles suspended in a motionless fluid— this centenary. These contributions can be classified into submitted in May; Towards the electrodynamics of moving three basic areas: geodynamics, geological (planetary) ca- bodies—submitted in June; and Does the inertia of a body tastrophism, and fluvial geomorphology. Regarding geo- depend on the energy it contains?—submitted in dynamics, Einstein essentially supported Hapgood’s very September. The World Year of Physics (2005) is an inter- controversial theory called Earth Crust Displacement. With national celebration to commemorate the 100th anniversary respect to geological (planetary) catastrophism, it is shown of Albert Einstein’s “Annus Mirabilis.” It also marks how the ideas of Einstein about Velikovsky’s proposals the 50th anniversary of Einstein’s death (McCrea and evolved from 1946 to 1955. Finally, in relation to fluvial Lawson 1955). The United Nations has officially de- geodynamics, the review incorporates the elegant work in clared 2005 as the International Year of Physics (APS which Einstein explains the formation of meandering 2005; Sathyasheelappa 2005; WYP 2005). rivers. A general analysis of his contributions is also carried However, the impact of Einstein’s theories was not out from today’s perspective. Given the interdisciplinarity restricted to physics and technological applications of and implications of Einstein’s achievements to multiple physics: Einstein’s achievements (1989) influenced philo- fields of knowledge, we propose that the year 2005 serve, sophy, art, history of science, literature, and many other rather than to confine his universal figure within a specific disciplines (Byrne 1980; Goenner and Castagnetti 1996; scientific area, to broaden it for a better appreciation of this Hentschel 1986). Beyond the general implications for brilliant scientist in all of his dimensions. geophysics and other geosciences of his revolutionary ideas on magnetism and gravity, Einstein also made significant, and much more specific, contributions to Earth Sciences. J. Martínez-Frías (*) . D. Hochberg . F. Rull One could even speculate that such interest, particularly Centro de Astrobiologia (CSIC/INTA), associated with the related to some geomorphological fluvial problems, could NASA Astrobiology Institute, mark, in a certain way, his son’s vocation: a renowned Ctra de Ajalvir, km 4, hydraulic engineer who is famous in his own right for his 28850 Torrejon de Ardoz, Madrid, Spain e-mail: [email protected] sediment transport equation (Ettema and Mutel 2004). Tel.: +34-91-5201111 However, these works are dispersed and poorly known Fax: +34-91-5201621 essentially because (a) they were eclipsed by his major scientific accomplishments and (b) his geosciences-related F. Rull Cristalografía y Mineralogía, Facultad de Ciencias and Unidad notes, letters, comments, and even scientific articles are Asociada al Centro de Astrobiologia, disperse (not constituting nor collected together as a Universidad de Valladolid-CSIC, 47006 Valladolid, Spain thematic whole). In fact, to the best of our knowledge, and after conducting an exhaustive search in the Institute The following Einstein quotation illustrates very well for Scientific Information (ISI) Web of Science, the present how Einstein was knowledgeable and aware of the work is the first scientific review article which brings together geodynamical intricacies: all this geological information. These contributions can be classified into three basic areas: geodynamics, geological In a polar region there is a continual deposition of ice, (planetary) catastrophism, and fluvial geomorphology. which is not symmetrically distributed about the pole. The earth’s rotation acts on these unsymmetrically deposited masses, and produces centrifugal momen- Geodynamics tum that is transmitted to the rigid crust of the earth. The constantly increasing centrifugal momentum pro- Geodynamics is the study of the processes and mechanisms duced in this way will, when it has reached a certain that shape, and have shaped, our planet in the past, from the point, produce a movement of the earth’s crust over the longest to the shortest length- and time-scales: from plate rest of the earth’s body, and will displace the polar motions to microscopic crystal deformation and magma regions toward the equator. (p. 1 in (Hapgood 1958)). migration, and from millions of years to minutes. Einstein’s scientific considerations on this topic are It is important to note that, although Einstein wrote this, principally connected to crustal geodynamics and are ex- he had doubts that the weight of the ice caps would have pounded in a series of correspondences in the mid- been sufficient to move the crust. Thus, in endorsing 1950s with Charles Hapgood (courtesy of the Einstein Hapgood’s work, Einstein however did so with some Archives Online, http://www.alberteinstein.info/). Hapgood lingering concerns. (1958) developed a controversial theory called Earth Crust Displacement (ECD), according to which the earth’slith- Without a doubt the earth’s crust is strong enough not osphere can sometimes move as a whole over the to give way proportionately as the ice is deposited. The asthenosphere. only doubtful assumption is that the earth’s crust can The proposed mechanism for these crustal displacements be moved easily enough over the inner layers. is related to the build-up of thick ice-sheets in polar and near-polar regions. This idea is a global geological theory Nevertheless, Albert Einstein wrote about Charles which, in conjunction with many other anomalies of earth Hapgood’s theory of Earth Crust Displacement in a letter science, attempts in a sophisticated (but also controversial) to William Farrington (Flem-Ath 2002) of the Department (Martínez-Frías and Barrera 2000) way to elucidate how of Geology and Mineralogy at the University of Massa- and why large parts of Antarctica could have remained ice- chusetts: “I think that the idea of Mr. Hapgood has to be free until recently. Hapgood claimed that towards the end of taken quite seriously.” the last ice age, the widespread mass of glacial ice covering Hapgood and Einstein continued to correspond and the northern continents provoked the lithosphere to “slip” finally met in January of 1955. Einstein’s last letter to over the asthenosphere, moving Antarctica, for several Hapgood was dated the 9th of March 1955, just weeks centuries, from a location in the middle latitudes to its before he died on the 18th of April 1955. current position and, in unison, rotating the other con- What is the situation concerning these ideas from today’s tinents. Antarctica’s movement to the polar region pre- perspective? It appears to be clear that the geologic rev- cipitated the growth of its ice cap. Similarly, by shifting the olution that took place in the 1960s—explicitly, the de- northern ice sheets out of the arctic zone, the end of the ice velopment of plate tectonics—overshadowed Hapgood’s age was made possible. Support for this theory was given theory. The data demonstrating that the poles were in dif- by Einstein. ferent positions (very slight shifts) during the Pleistocene are convincing (Eden 2005) and explained why Hapgood’s I frequently receive communications from people who theory was seriously considered by scientists such as wish to consult me concerning their unpublished ideas. Einstein and K. F. Mather (a prestigious geomorphologist It goes without saying that these ideas are very seldom and paleontologist). However, plate tectonics had unified possessed of scientific validity. The very first com- many of the features and characteristics of seafloor munication, however, that I received from Mr. spreading and continental drift into a coherent model and Hapgood electrified me. His idea is original, of great had “renovated” geologists’ understanding of ocean basins, simplicity, and—if it continues to prove itself—of continents, mountains, and earth history. In fact, Hapgood great importance to everything that is related to the himself first realized the huge amount of evidence re- history of the earth’s surface. (Einstein, 18th of