After initially supporting continental drift, the late Australian geologist S. Warren Carey advocated expansion from the 1950s (before the development of plate tectonics provided the generally accepted explanation of the movement of continents) to his death,
demonstrating that
subduction
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...
and
other events could not balance the
sea-floor spreading at
oceanic ridge
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a diverg ...
s, and piling yet unresolved paradoxes that continue to plague plate tectonics. Starting in 1956, he proposed some sort of mass increase in the planets and said that a final solution to the problem is only possible in a
cosmological
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', and in 1731 taken up in Latin by German philosopher ...
perspective in connection with the
expansion of the universe
The expansion of the universe is the increase in distance between any two given gravitationally unbound parts of the observable universe with time. It is an intrinsic expansion whereby the scale of space itself changes. The universe does not exp ...
.
Bruce Heezen
Bruce Charles Heezen (; April 11, 1924 – June 21, 1977) was an American geologist. He worked with oceanographic cartographer Marie Tharp at Columbia University to map the Mid-Atlantic Ridge in the 1950s.
Biography
Heezen was born in Vinton, Io ...
initially interpreted his work on the mid-Atlantic ridge as supporting S. Warren Carey's Expanding Earth Theory, but later withdrew his support, finally convinced by the data and analysis of his assistant,
Marie Tharp
Marie Tharp (July 30, 1920 – August 23, 2006) was an American geologist and oceanographic cartographer. In the 1950s, she collaborated with geologist Bruce Heezen to produce the first scientific map of the Atlantic Ocean floor. Her cartograp ...
. The remaining proponents after the 1970s, like the Australian geologist James Maxlow, are mainly inspired by Carey's ideas.
To date no scientific mechanism of action has been proposed for this addition of new mass. This is a big obstacle for acceptance of the theory by other geologists.
It is a well known fact that the earth is constantly acquiring mass through accumulation of rocks and dust from space, as are all other planetary bodies in our system. According to NASA, "Every day about 100 tons of meteoroids -- fragments of dust and gravel and sometimes even big rocks – enter the Earth's atmosphere." The majority of this debris burns up in the atmosphere and lands as dust. Such accretion, however, is only a minuscule fraction of the mass increase required by the growing earth hypothesis.
Decrease of the gravitational constant
Paul Dirac
Paul Adrien Maurice Dirac (; 8 August 1902 – 20 October 1984) was an English theoretical physicist who is regarded as one of the most significant physicists of the 20th century. He was the Lucasian Professor of Mathematics at the Univer ...
suggested in 1938 that the universal
gravitational constant
The gravitational constant (also known as the universal gravitational constant, the Newtonian constant of gravitation, or the Cavendish gravitational constant), denoted by the capital letter , is an empirical physical constant involved in ...
had ''decreased'' in the billions of years of its existence. This led German physicist
Pascual Jordan
Ernst Pascual Jordan (; 18 October 1902 – 31 July 1980) was a German theoretical and mathematical physicist who made significant contributions to quantum mechanics and quantum field theory. He contributed much to the mathematical form of matri ...
to a modification of
general relativity
General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics ...
and to propose in 1964 that all planets slowly expand. This explanation is within the framework of physics considered as a viable hypothesis.
Measurements of a possible variation of the gravitational constant showed an upper limit for a relative change of per year, excluding Jordan's idea.
Formation from a gas giant
According to the hypothesis of
J. Marvin Herndon (2005, 2013) the Earth originated in its
protoplanetary stage from a
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...
-like
gas giant
A gas giant is a giant planet composed mainly of hydrogen and helium. Gas giants are also called failed stars because they contain the same basic elements as a star. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" ...
. During development phases of the young
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
, which resembled to those of a
T Tauri star
T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus star-forming region. They are found near molecular clouds and iden ...
, the dense atmosphere of the gas giant was stripped off by infrared eruptions from the sun. The remnant was a rocky planet. Due to the loss of pressure from its atmosphere would have begun a progressive decompression. Herndon regards the energy released due to the lack of compression as a primary energy source for geotectonic activity, to which some energy from radioactive decomposition processes was added. He calls the resulting changes in the course of
Earth's history
The history of Earth concerns the development of planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to understanding of the main events of Earth's past, characterized by constant geologic ...
by the name of his theory ''Whole-Earth Decompression Dynamics''. He considered the
seafloor spreading
Seafloor spreading or Seafloor spread is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.
History of study
Earlier theories by Alfred Wegener an ...
at
divergent plate boundaries as an effect of it.
In his opinion
mantle convection
Mantle convection is the very slow creeping motion of Earth's solid silicate mantle as convection currents carrying heat from the interior to the planet's surface.
The Earth's surface lithosphere rides atop the asthenosphere and the two form ...
used as concept in the theory of
plate tectonics
Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...
is physically impossible. His theory includes the effect of
solar wind
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sola ...
(
geomagnetic storms
A geomagnetic storm, also known as a magnetic storm, is a temporary disturbance of the Earth's magnetosphere caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth's magnetic field.
The disturbance that d ...
) as cause for the reversals of the
Earth magnetic field. The question of mass increase is not addressed.
Main arguments against Earth expansion
The hypothesis had never developed a plausible and verifiable mechanism of action.
During the 1960s, the theory of
plate tectonics
Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...
—initially based on the assumption that Earth's size remains constant, and relating the
subduction zones to burying of lithosphere at a scale comparable to seafloor spreading
—became the accepted explanation in the Earth Sciences.
The scientific community finds that significant evidence contradicts the Expanding Earth theory, and that evidence used in support of it is better explained by plate tectonics:
*Measurements with modern high-precision
geodetic
Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...
techniques and modeling of the measurements by the horizontal motions of independent rigid plates at the surface of a globe of free radius, were proposed as evidence that Earth is not currently increasing in size to within a measurement accuracy of 0.2 mm per year.
The lead author of the study stated "Our study provides an independent confirmation that the solid Earth is not getting larger at present, within current measurement uncertainties".
* The motions of
tectonic plates
Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...
and subduction zones measured by a large range of geological, geodetic and geophysical techniques supports plate tectonics.
[Fowler (1990), pp 281 & 320–327; Duff (1993), pp 609–613; Stanley (1999), pp 223–226]
* Imaging of lithosphere fragments within the mantle supports lithosphere consumption by subduction.
*
Paleomagnetic
Paleomagnetism (or palaeomagnetismsee ), is the study of magnetic fields recorded in rocks, sediment, or archeological materials. Geophysicists who specialize in paleomagnetism are called ''paleomagnetists.''
Certain magnetic minerals in rock ...
data has been used to calculate that the radius of Earth 400 million years ago was 102 ± 2.8 percent of today's radius.
*Examinations of data from the Paleozoic and Earth's
moment of inertia suggest that there has been no significant change of Earth's radius in the last 620 million years.
See also
*
:Plate tectonics
*
Timeline of the development of tectonophysics (before 1954)
The evolution of tectonophysics is closely linked to the history of the continental drift and plate tectonics hypotheses. The continental drift/ Airy-Heiskanen isostasy hypothesis had many flaws and scarce data. The fixist/ Pratt-Hayford isostasy ...
*
Timeline of the development of tectonophysics (after 1952)
Notes
Bibliography
* ; 1976: "The Expanding Earth", Developments in Geotectonics (10), Elsevier, ; digital edition 2013: ASIN B01E3II6VY.
* ;1988: "Theories of the Earth and Universe: A History of Dogma in the Earth Sciences", Stanford University Press, .
* ; 1993: ''
Holmes' principles of physical geology'', Chapman & Hall (4th ed.), .
* ; 1990: ''The Solid Earth, an introduction to Global Geophysics'', Cambridge University Press, .
* ; 1999: ''Earth System History'', W.H. Freeman & Co, .
External links
* {{Commons-inline, Expanding Earth, Expanding Earth
Historical
*
Ott Christoph Hilgenberg
Ott, OTT or O.T.T. may refer to:
Entertainment
* OTT (group), a pop band from the late 1990s
* Ott (record producer), British record producer and musician
* "O.T.T" (song), a song by Fugative
* ''O.T.T.'' (television series), a UK TV programme f ...
:
* G. Scalera
Roberto Mantovani an Italian defender of the continental drift and planetary expansion* Giancarlo Scalera
Variable Radius CartographyBirth and Perspectives of a New Experimental Discipline* G. Scalera, Braun
Ott Christoph Hilgenberg in twentieth-century geophysics* G. Scalera
Samuel Warren Carey – Commemorative memoir
* Andrew Alden
Contemporary
Database of Expansion Tectonic Scientists, living and deceased
Structure of the Earth
Geophysics
Geodynamics
Obsolete geology theories