Theory -> Law?

[Numenor]

I always thought that technically speaking a Theory never get to 'graduate' into a Law because it could always be falsified by evidence which could arise at any time. But during some googling tonight I came across a webpage which seemed to be saying that a Theory can become a Law. Thoughts?

http://pasadena.wr.usgs.gov/office/ganderson/es10/lectures/lecture01/lecture01.html

This diagram demonstrates the point the notes are making:

 

[Locrian]

It all depends on how you define the terms, which scientists spend little time doing and even less time using appropriately. It seems to me that at least half the "laws" in physics are old ideas that have been shown to be demonstrably false in many circumstances. This does not preclude them from being useful in many other circumstances, but the term law seems too strong.

I also find that chart amusing. If you look too carefully you see that few in science really spend a lot of time going through the process like that because it is either implied or unnecessary. What's more, the chart leaves off (but implies, in a poor way) the most important part of modern scientific method: peer review.

 

[DaveS]

I suppose a theory becomes law when it is applied. For example, the orbit of celestial objects was proven when the first spacecraft orbited the Earth, E = MC2 was proven when the atom bomb blew over Hiroshima and Nagasaki. Those could now be considered 'law' I suppose as they have been shown to be true.

 

[billwald]

"Law" is better reserved for legal stuff. Christian's use "law" to confuse people and themselves. Before the rationalists came along the alchemists searched for formula and incantations by which God micromanaged the universe.

 

[Darkhorse]

To my understanding, there is no formal procedure to "graduate" a theory into a law. It seems to be more a matter of historical seniority. Newton's 3 laws of motion were contradicted (some would say "updated") in 1905 by Einstein's special theory of relativity. Since then, Newton's laws have been proven inadaquate for very small particles and very high speeds, but Einstein's theory has not yet been proven wrong (it has been verified many times, though).

Science is based on inductive reasoning: "since I let go of a rock 10 times and it fell each time, then I can conclude that the rock will fall every time I let go of it". The Scientific Method is simply a formalized procedure to expand knowledge through reproducable experiments. Any law, theory, or hypothesis of science can be overturned by one reproducable example where it doesn't work.

 

[delight1]

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.

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.

An analogy can be made using a slingshot and an automobile.

A scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back.

An automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged.

A theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole. 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.

It is possible for a theory to graduate into law,but only a part of theory can do that.
As in theory of kinetic behavior of particle,the relationship with pressure and temperature became Boyle's and Charles Law.

 

[Kripost]

The relationship between 'law' and 'theory' is not that 'laws' are better than 'theories'. Laws state the relation in consise terms (e.g. F=G*m1*m2/r^2), whereas theory attempts to explain the relation, given the body of knowledge at that time.

Also, laws can be falsified, or superceeded by more accurate laws. The classic example would be Newton's law of gravity, which fails to explain mercury's orbit, and also does not hold for bodies moving near the speed of light.

In other words, theories do not graduate into laws.

 

[bob135]

In some sciences, Laws are simply ideals which do not have as much predictive value as theories. A theory tries to explain a phenomenon in detail, while a law just gets the general idea. The ideal gas law, for example, assumes that gas particles have no mass and no intermolecular forces. Obviously, this isn't true, but the law ignores it.

 

[AngelusTenebrae]

Newton's laws work in terms of classical physics, but the only reason it's still taught is because it is still an effective approximation, even if it isn't right. The distinction I make between theory and law is that law is a statement made, that can come from a hypothesis, observation or tests. Theory goes into more detail, and usually has more equations or explanations related to it. That's why you can't call evolution a law because it's simply too detailed to be crammed into a single statement. If it could be, creationists should know what they're talking about on evolution, but they often don't. A law is no more credible than a theory is; both arise from methods of observations and repeated experiments, but both of them make no absolute claim. They are both subject to probability.

 

[mnphysicist]

Theories are a best guess as to what may be a reasonable model, and are only correct within a limited point of view. Laws are the same, but its an issue more so with English language than a degree of correctness. Newton was wrong, Einstrein will be proven wrong, and so will the next generation of theories and laws. However, by being wrong does not mean we can't generate valid predictions, or create value from theories or laws. However, to accept them as absolutes can serve to shoot one in the foot as well.

Personally I'm not a big fan of peer review. Its a whole lot better than a free for all of unsubstantiated and non reproduceable claims published as fact or just anecdotal evidence. Otoh, when something is under peer review, politics and economics dominate much of the time, so it can be counterproductive as well. Now, if peer review was accomplished in a similar fashion to digg, or perhaps slashdot with weightings assigned, perhaps the economic factor would be less... but politics might be greater, not sure. There is not an easy answer.

Ron

 

[billwald]

"Law" better used in religion or the courts. It is to confusing to use in science.

A theory is a well demonstrated hypothesis. Theories can only be falsified, never proven.

 

[simplicity]

This is certainly the prevailing structure to interpret, handle and resolve problems in Western culture. It tends to be rather linear and as the diagram suggests prone to boolean testing near the end. It relies on absolutism - the fact that the contributing evidence is itself stable, static or in any event true. It's probably the greatest hurdle science will ever have to overcome to delve into the new frontiers of abstraction and relativism that made possible by computer technology.

 

[Talcara]

Laws (of Nature) are theories that pass every test, are not contradicted by any observation and apply without exception. Such laws include the first and second laws of thermodynamics, for example. IMHO. These laws of nature are absolute and if any theory crosses against these laws, the theory is wrong. If, however, an observation is seen to contradict these laws, then we must assume that they were never really laws of nature in the first place.

 

[Kripost]

Laws (of Nature) are theories that pass every test, are not contradicted by any observation and apply without exception. Such laws include the first and second laws of thermodynamics, for example. IMHO. These laws of nature are absolute and if any theory crosses against these laws, the theory is wrong. If, however, an observation is seen to contradict these laws, then we must assume that they were never really laws of nature in the first place.

The problem with the that statement is these: "theories that pass every test", and "laws of nature are absolute".

Firstly, it is not possible to design experiments which test for each and every condition. Thus, given a set of observations (as long as the set is finite), and a law is derived from these observations, it is possible that there exist one or more observation which contradict that partocular law. This would in turn imply that laws can only exist in mathematics, and never in physical science.

Secondly, by using this definition of law, that would imply that Newton's gravitational law: F=(G*m1*m2)/(r^2) and Ideal Gas laws are not laws, since Newton's law failed to accurately predict the orbit of Mercury, and ideal gases do not exist. In other words, these laws are not absolute.

 

[mark kennedy]

Hypothesis can be tested to the point where they graduated to a valid theory. Theory carries with it a lot of futher questions meant to be developed and researched further, that is the whole idea of a theory. A law is universal, for instance, Mendel's laws of inheritance pertain to all sexually reproducing organism. In April 16,1676 Sir Issac Newton performed his experimentum crucis (meticulas experiment) for the Royal Society in London demonstrating that light was composed of 7 colors raising it to the level of a valid theory. This never became a law of science per se since for every tested hypothesis there are two new lines of testing suggested. Newton's optics did become part of the law of gravity aka the principles of motion in the principia which is largely focus on calculas applied to astronomy, physics, motion ...etc

Science has been focused on experimentation ever since, it wasn't allways like that. Aristotlian deductive reasoning was considered perfectly valid ways of explaining nature, after Newton insisted that his theory could only be argued against using experimental methods this changed science into demonstrative proofs, period. A modern application of this would be the good ole string theory with it's elaborate speculations about time and space travel. Einstein was into a unified theory of physics but was never able to come up with one which in no way invalidates his work on relativity or further work on Quantum mechanics and mathamatics.

If you did Newton's experimentum crucis you would still get the exact same results. Newton's theory of light is still valid but never ascended to a universal principle that transended the many subcatagories of physics. Theory and practice are discerably different ways of undertanding the world around us but ultimatly they are two parts of the same thing.

Have a nice day
Mark