Ask A Scientist General Science Archive

name         Destiny
status       student
grade        9-12
location     TX

Question -   Where can I find information on theories that were proven 
wrong?
---------------------------------------
Answer: Rumor has it that "Fads & Fallacies in the Name of Science" by
Martin Gardner is just what your looking for.

Michael Loop Ph.D.
====================================================================
Before looking for "theories" that were "proven wrong", make sure you 
understand what a (scientific) theory is, because a scientific theory is 
more specific than the colloquial use of the word theory as "a guess".
A scientific theory is:
    "A well-substantiated explanation of some aspect of the natural world; 
an organized system of accepted         knowledge that applies in a variety 
of circumstances to explain a specific set of phenomena."
So for an explanation to pass the test of being a "scientific theory" it 
must meet a higher standard of rigor and generality than "my guess". First: 
Scientific theories are seldom, if ever, "right" or "wrong" in an absolute 
sense. Second: One has to be careful about tossing the term "proven" around 
loosely. What does "proven" mean? By its definition a scientific theory is 
"organized", "generally accepted", and "widely applicable". However, a 
"scientific theory" explains or applies to a "specific set of phenomena". 
Examples: Newton's theory of mechanics and Maxwell's theory of 
electromagnetism are well established theories within the context of their 
applicability, but they are not "universal", in the sense that one can find 
some set of conditions where they do not apply. Neither theory applies to 
atoms and molecules. A new theory, quantum mechanics, was developed to 
"explain" the behavior of atoms and molecules -- but even quantum mechanics 
has its boundaries of applicabilty. Neither Newton's, Maxwell's, nor 
"quantum" theory applies to conditions where the speed of particles 
approaches the speed of light. Here Einstein developed the theory of special 
relativity. And even special relativity does not apply in circumstances 
where gravity is a significant factor. In such cases the "general theory of 
relativity" must be used to correctly describe, explain, and predict 
experimental observations. Remember -- the "gold standard" is: "Does the 
theory correctly predict some phenomena that can be measured 
experimentally." To this day there is no satisfactory theory that correctly 
predicts conditions where both "gravity" and "quantum mechanics" play a 
significant role. That does not make either one "disproved". It only 
identifies their boundaries of applicability.
    A "hot debate" these days is the "theory of evolution". Proponents of 
"creationism" and "intelligent design" proclaim the "theory of evolution" is 
ONLY a theory, but they are using THEORY to mean "a guess". This is a misuse 
of the term as scientists use the term THEORY. However, "creationists" and 
"intelligent designers" have no experimental data to "put on the table" to 
be examined, verified, or refuted. Instead, they proclaim that "evolution" 
is not universal, that it does not explain every aspect of biological 
development. Nobody who understands "evolution" claims that it does. All 
"theories" are the product of human intelligence, and there is no theory of 
"everything".
    Advances in chemistry are unraveling the chemical structure of DNA and 
other complex biological molecules. In the not too distant future the 
connection between various species (and even individuals) will be a "simple" 
matter of chemical analysis of the molecules that define "species" and 
"individuals" within species. Then the protagonists of "creationism" and 
"intelligent design" are going to have to refute "chemistry" as a science. 
They will have to claim that the chemical analysis of the building blocks of 
species and individuals are "theory", "just a guess". Interesting.
    The term "proof" belongs in axiomatic logical systems. I 
"prove"/"disprove" a mathematical theorem by showing that it is consistent 
with the axioms of the mathematical system.  It is only the logical 
consistency of the theorem with those axioms that is important. But I am 
free to setup whatever axioms I choose. As an example, there are several 
self-consistent geometries related to traditional Euclidian geometry. 
Euclidian geometry ASSUMES parallel lines never cross, another "geometry" on 
the surface of a sphere ASSUMES (correctly) that parallel lines (at the 
equator) cross (at the North Pole) and (at the South Pole). One isn't 
"right" and the other "wrong" -- they are just different.
    That is a different process than testing a theory in the experimental 
sciences, which compares prediction with experimental data.

Vince Calder
====================================================================
    Every scientific theory is wrong in some respect. There is no
scientific theory of "everything".  The point is this. A theory is "a
well-substantiated explanation of some aspect of the natural world; an
organized system of accepted knowledge that applies in a variety of
circumstances to explain a specific set of phenomena." [definition from
"WordWeb Pro"]
     Physical theories are not "proven" or "disproved". They apply, or do not
apply, to some set of observations.  In mathematics "proved" means the
theorem (statement about the elements of the axioms) are logically
consistent with the axioms. That does not mean it is "true", that is, "right"
versus "wrong". So for example, the theory of real numbers is totally
encompassed by the theory of complex numbers, but that does not make the
theory of real numbers "wrong". It only specifies its limits and consistency
within the axioms of the mathematical theory.
     Physical theories, for example, Newtonian mechanics, applies to a
certain range of measurement. It applies to most of the world as we observe
it with our senses. However, at the atomic level, it does not make the
correct prediction of what is OBSERVED. At conditions where the speeds
approach the speed of light it does not make the correct prediction of what
is OBSERVED. In these two examples, quantum mechanics and relativistic
mechanics respectively, do predict what is OBSERVED. This doesn't make
Newtonian mechanics "right" versus "wrong".
     There is a current, actually recurrent, debate on whether "the theory of
evolution" is "right" or "wrong". The debate misses the point. It is neither
"right" nor is it "wrong". The measure is: Does "evolution" explain many of
the OBSERVATIONS of the genetic relation between species. Most scientists
believe it does, and have experimental DATA to support their OBSERVATIONS
and the limits of their observations . Advocates of "creationism" and/or
"intelligent design", on the other hand, invoke absolute "right" or "wrong"
based upon articles of Christian faith. Other faith traditions, even
Christian traditions, do not accept that position. So physical theories do
not address absolute "truth" versus absolute "false".
     It is interesting and ironic that a Catholic monk, Mendel, first
"explained" genetic relationships and Georges Lemaître, a Jesuit priest,
first proposed what is now called the "Big Bang". Neither felt their "faith"
was compromised.

Vince Calder
====================================================================