Scientific Laws, Hypotheses, and Theories

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Scientific Laws, Hypotheses, and Theories

• What do these scientific terms mean?
• People often misinterpret these terms.
• Lets look at the language used by scientists.

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Scientific Laws, Hypotheses, and Theories

• In laymans terms, if something is said to be
  just a theory, it usually means that it is a
  mere guess, or is unproved. It might even lack
  credibility.

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Scientific Laws, Hypotheses, and Theories

• In scientific terms, a theory implies that
  something has been proven and is generally
  accepted as being true.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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THEORIES ON WHY THE ANCIENTS BUILT STONEHENGE

• It was an early attempt to precisely map
  positions of stars and planets to facilitate
  better horoscope writing.
• A few people drank too many cups of espresso one
  morning, had to work it off.
• It was a technological innovation from a people
  way ahead of their time, as explained by the
  little-known inscription "Someday we will be
  able to use this to receive something called
  'satellite TV' for free."

http//www.grinningplanet.com/2004/06-22/stoneheng
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Lets Look At The Definitions

• Hypothesis This is an educated guess based upon
  observation. It is a rational explanation of a
  single event or phenomenon based upon what is
  observed, but which has not been proved. Most
  hypotheses can be supported or refuted by
  experimentation or continued observation.

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Theory

• Theory A theory is more like a scientific law
  than a hypothesis. A theory is an explanation of
  a set of related observations or events based
  upon proven hypotheses and verified multiple
  times by detached groups of researchers. One
  scientist cannot create a theory he can only
  create a hypothesis.

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Shorter Version

• To scientists, a theory is a coherent explanation
  for a large number of facts and observations
  about the natural world.

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Scientific Law

• Scientific Law This is a statement of fact meant
  to explain, in concise terms, an action or set of
  actions. It is generally accepted to be true and
  universal, and can sometimes be expressed in
  terms of a single mathematical equation.
  Scientific laws are similar to mathematical
  postulates. They dont really need any complex
  external proofs they are accepted at face value
  based upon the fact that they have always been
  observed to be true.

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Examples of Hypotheses
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Examples of Theories

• Some scientific theories include the theory of
  evolution, the theory of relativity, and the
  quantum theory. All of these theories are well
  documented and proved beyond reasonable doubt.
  Yet scientists continue to tinker with the
  component hypotheses of each theory in an attempt
  to make them more elegant and concise, or to make
  them more all-encompassing. Theories can be
  tweaked, but they are seldom, if ever, entirely
  replaced.

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Examples of Theories
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Examples of Scientific Laws

• Law of gravity
• The law of thermodynamics
• Hooks law of elasticity.

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More Examples of Scientific Laws

• In the late 17th Century, Nicholas Steno
  established some natural laws relating to
  geology.
• The law of original horizontality - this states
  that when sediments are deposited in water, they
  will sink through it and deposit as horizontal
  layers as the result of gravity (unless acted on
  by other forces).
• The law of stratigraphic succession - this states
  that in a given sequence of sediments, the oldest
  will be at the bottom and the youngest at the
  top. It does not provide ages for those
  sediments, simply the sequence of their
  deposition.

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LAW VERSE THEORY

• The biggest difference between a law and a theory
  is that a theory is much more complex and
  dynamic.
• A law governs a single action, whereas a theory
  explains a whole series of related phenomena

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LAW VERSE THEORY

• In general, both a scientific theory and a
  scientific law are accepted to be true by the
  scientific community as a whole. Both are used to
  make predictions of events. Both are used to
  advance technology.

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Credit

• http//wilstar.com/theories.htm
• http//sci.waikato.ac.nz/evolution/Theories.shtml