Transcript What is Science - s3.amazonaws.com

What is science?
• Science is the study of the natural world in
an attempt to explain how it works.
What is a scientific theory?
• A scientific theory is the best explanation
based on evidence of why things are or
why a phenomenon takes place without
regards to how it works or behaves.
• Example: The Theory of Gravitation set forth by Einstein
is the best explanation of why objects attract each other
in that massive objects warp the space around them and
objects are simply following the warped space when the
are attracted.
What is a scientific law?
• Scientific laws attempt to explain describe
phenomena without regards to why it
works. Laws often use equations to
describe.
• Example: the Law of Gravitation
F = G m1m2 / d2
Science is
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Consistent
Observable
Natural
Predictive
Peer reviewed
Testable
Tentative
Simple
Consistent
• Every time we observe the phenomenon, it
must happen the same way.
• If I dropped a ball and it fell away from the
Earth, science would need to revise the
theory of gravity.
• Science is internally consistent. One part
of science may not contradict what
another part maintains.
Observable
• Directly through our 5 senses or indirectly
through use of equipment, we must be
able to observe the evidence for a
scientific theory or law.
• Equipment such as an electron
microscope, a cloud chamber etc.
Natural
• Science does not use explanations that
invoke the supernatural.
• All evidence for science must be from the
natural world and observable by our
senses or equipment.
God is not able to be understood or
proven by science because God is
supernatural.
Predictive
• A theory or law must make predictions
about the natural world that can be tested.
• If the tests yield the expected results, this
provides evidence or support for the
theory or law.
Einstein’s theory of general relativity predicted that light would
be bent as it passed a large body such as a star like light is
bent when a spoon is in a glass of water. Observations made
during an eclipse showed it was.
Peer Reviewed
• When a scientist does research, for that
work to be accepted it must be published
for other scientists to comment on and
verify.
Scientists announced that they had
discovered “cold” fusion. When other
scientists tried to verify their work, they did
not achieve the same results. Their work was
discredited.
Testable
• The predictions made by a scientific theory
or law must be able to be tested by
experimentation or observation.
String theory does not make
predictions that we can test given the
current level of our technology.
Therefore, while interesting it is not an
accepted scientific explanation.
Tentative
• Scientific theories or laws are always
subject to change or rejection.
• Because they must be consistent, even
one counterexample will cause
examination of a theory or law.
It was assumed that time was the same for all
observers. Einstein showed that light speed is the
same for all observers not time. This led to the
revision of many of Newton’s Laws.
Simple
• If many explanations of a phenomenon
exist, the simplest is the one chosen.
Ptolemy was able to predict the location of the
planets in the sky using a complex series of
calculations. Kepler’s model of the elliptical orbits of
the planets was much simpler and just as accurate.
It replaced Ptolemy's.
Think About
• Think of something that you believe to be
true that is not accepted by the scientific
community.
• Why do you think something such as
anthropogenic climate change which has
overwhelming scientific evidence is not
accepted by many intelligent nonscientists?