In order for it to be scientific, however, a scientist must be able to test the explanation to see if it works and if it is able to correctly predict what will happen in a situation. What is a Theory? The United States National Academy of Sciences describes what a theory is as follows: "Some scientific explanations are so well established that no new evidence is likely to alter them. Note some key features of theories that are important to understand from this description: Theories are explanations of natural phenomena.
They aren't predictions although we may use theories to make predictions. They are explanations as to why we observe something. Theories aren't likely to change. They have a large amount of support and are able to satisfactorily explain numerous observations. Theories can, indeed, be facts. Theories can change, but it is a long and difficult process.
In order for a theory to change, there must be many observations or pieces of evidence that the theory cannot explain. Theories are not guesses. The phrase "just a theory" has no room in science. To be a scientific theory carries a lot of weight; it is not just one person's idea about something Theories aren't likely to change. What is a Law? What is a Belief? Laws vs. Theories A common misconception is that scientific theories are rudimentary ideas that will eventually graduate into scientific laws when enough data and evidence has accumulated.
Summary A hypothesis is a tentative explanation that can be tested by further investigation. A theory is a well-supported explanation of observations. A scientific law is a statement that summarizes the relationship between variables. If the circumstance changes, then the law would change.
For example, in the vacuum of space, the apple may float upward from the tree instead of downward. Many scientific laws can be boiled down to a mathematical equation. For example, Newton's Law of Universal Gravitation states:. F g is the force of gravity; G is the universal gravitational constant, which can be measured; m1 and m2 are the masses of the two objects, and d is the distance between them, according to Ohio State University.
Another example of where mathematics influences scientific law is probabilities. With large numbers, probability always works. The house always wins," said Dr. This is known as the confidence interval. For example, we can be 95 percent certain that what we are trying to estimate lies within a certain range or we can be more certain, say 99 percent certain, that it lies within a wider range.
Just like in life in general, we must accept that there is a trade-off. Just because an idea becomes a law, doesn't mean that it can't be changed through scientific research in the future. The use of the word "law" by laymen and scientists differ.
When most people talk about a law, they mean something that is absolute. A scientific law is much more flexible. It can have exceptions, be proven wrong or evolve over time, according to the University of California.
Exceptions have been found. Theories can also evolve. The evolution from Newtonian physics to general relativity is a good way to explain how new information can cause a theory to evolve into a more complete theory:.
Albert Einstein later discovered the theories of special and general relativity — that the force of gravity exists due to the bending of spacetime, which is caused by massive objects. This created a more complete theory of gravity. He just had a partial answer. In this case, scientists made observations, hypotheses, and testable predictions to figure out which theory was right.
For example, one scientist might observe that the universe is expanding, hypothesize that it had a beginning, and test their hypothesis by doing the math. Eventually, either one theory is overturned completely in this case, the Big Bang theory turned out to be correct , or the correct aspects of each theory are combined to form a new theory — one singular theory.
In many cases, one theory forms the foundation upon which other theories are built. Scientific laws are short, sweet, and always true. Laws are accepted as being universal and are the cornerstones of science. They must never be wrong that is why there are many theories and few laws.
If a law were ever to be shown false, any science built on that law would also be wrong. A law is used to describe an action under certain circumstances. A theory describes how and why something happens. For example, evolution by natural selection is a theory.
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