Superseded scientific theories

From Wikipedia, the free encyclopedia

You have new messages (last change).
The obsolete Geocentric model of the universe places the Earth at the centre.
The obsolete Geocentric model of the universe places the Earth at the centre.

A superseded, or obsolete, scientific theory is a scientific theory that was once commonly accepted but (for whatever reason) is no longer considered the most complete description of reality by mainstream science; or a falsifiable theory which has been shown to be false. This label does not cover theories that are yet to gain wide support in the scientific community (protoscience or fringe science). This also does not cover theories that were never widely accepted. Some theories which were only supported under specific political authorities, like Lysenkoism, may also be included.

In some cases, the theory has been completely discarded. In other cases, the theory is still useful because it provides a description that is "good enough" for a particular situation, and is more easily used than the complete theory (often because the complete theory is too mathematically complex to be easily usable). An example of this is the use of Newtonian physics in many mechanical engineering applications, and even in calculating the orbits of satellites, because the deviation from such physics is smaller than other sources of error. Karl Popper suggested that all scientific theories should be falsifiable otherwise they could not be tested by experiment. Anything that cannot be shown by experiment to be false would therefore be an axiom and have an absolute status, beyond any confirmation or refutation.

Contents

[edit] Superseded biology theories

Giraffes are often invoked in explanations of Lamarck's superseded theory of evolution. In Lamarckism, a giraffe is able to lengthen its neck over its life time, for example by stretching to reach higher leaves, and subsequently have an offspring with a longer neck. The theory has been superseded by the understanding of natural selection as the primary mechanism of evolution.
Giraffes are often invoked in explanations of Lamarck's superseded theory of evolution. In Lamarckism, a giraffe is able to lengthen its neck over its life time, for example by stretching to reach higher leaves, and subsequently have an offspring with a longer neck. The theory has been superseded by the understanding of natural selection as the primary mechanism of evolution.

[edit] Superseded chemistry theories

[edit] Superseded physics theories

  • Plum pudding model of the atom - assuming the protons and electrons were mixed together in a single mass
  • Rutherford solar system model of the atom with an impenetrable nucleus orbitted by electrons.
  • Bohr model with quantized orbits
  • Electron cloud model following the invention of Quantum Mechanics in 1925 and the eventual atomic orbital models derived from the quantum mechanical solution to the hydrogen atom.

[edit] Superseded astronomical and cosmological theories

[edit] Superseded geographical and climatological theories

  • Flat Earth theory
  • The Open Polar Sea, an ice-free sea once supposed to surround the North Pole
  • Rain follows the plow - the theory that human settlement increases rainfall in arid regions (only true to the extent that crop fields evapotranspirate more than barren wilderness)

[edit] Superseded geological theories

[edit] Superseded medical theories

[edit] Obsolete branches of enquiry

[edit] Approximate theories

Here are theories that are no longer considered the most complete representation of reality, but are still useful in particular domains. For many theories a more complete model is known, but in practical use the coarser approximation provides good results with much less calculation.

[edit] See also

[edit] Lists

Retrieved from "http://en.wikipedia.org../../../s/u/p/Superseded_scientific_theories.html"
In other languages