Now, one scientist is arguing that people should do away with these misunderstood words altogether and replace them with the word "model.
It means we need better scientific education. From "theory" to "significant," here are seven scientific words that are often misused. The general public so widely misuses the words hypothesis , theory and law that scientists should stop using these terms, writes physicist Rhett Allain of Southeastern Louisiana University, in a blog post on Wired Science.
A hypothesis is a proposed explanation for something that can actually be tested. But "if you just ask anyone what a hypothesis is, they just immediately say 'educated guess,'" Allain said. Climate-change deniers and creationists have deployed the word "theory" to cast doubt on climate change and evolution. That's despite the fact that an overwhelming amount of evidence supports both human-caused climate change and Darwin's theory of evolution.
Part of the problem is that the word "theory" means something very different in lay language than it does in science: A scientific theory is an explanation of some aspect of the natural world that has been substantiated through repeated experiments or testing. But to the average Jane or Joe, a theory is just an idea that lives in someone's head, rather than an explanation rooted in experiment and testing.
However, theory isn't the only science phrase that causes trouble. Even Allain's preferred term to replace hypothesis, theory and law -- "model" -- has its troubles. The word not only refers to toy cars and runway walkers, but also means different things in different scientific fields. A climate model is very different from a mathematical model, for instance.
It has an appearance of solidity in physics right now mainly because of the Standard Model. By contrast, in genetics and evolution, 'models' are used very differently. When people don't accept human-caused climate change, the media often describes those individuals as " climate skeptics. It is contrarianism True skepticism is, as [Carl] Sagan described it, the 'self-correcting machinery' of science," Mann said. The phrase " nature versus nurture " also gives scientists a headache, because it radically simplifies a very complicated process, said Dan Kruger, an evolutionary biologist at the University of Michigan.
Genes may influence human beings, but so, too, do epigenetic changes. Compare this to the 19th century argument: The sun cannot produce enough power burning according to the known laws of calorimetry and thermodynamics, therefore there must be a constant source of new fuel for the sun.
We know this argument is likely false, but I cannot see any scientifically definable difference between this argument in the 19th century , and the supposition that dark matter is responsible for behavior that is different from our known set of rules.
In what way is the dark matter of the 20th century a more scientifically acceptable hypothesis than the dark energy hypothesis of the 19th century? This is a good question! I started to compile such a list, and it became obvious that it includes just about all of astronomy, directly or indirectly. For example, models of stars include hydrostatic equilibrium; evidence that gravity is not behaving the way we expect it to, outside the solar system, would show up as inconsistencies between these models and observations of stars.
Such inconsistencies could, potentially, be seen in asteroseismological data, or even in the HR diagram. I don't know anything about the 19th century argument, so I can't comment on the "better" part of your statement. So DM in astronomy is analogous to the neutrino, in at least two phases of its scientific history: from hypothesis to direct detection , and from the 'solar neutrino problem' s?
Looked at in another way, "DM as evidence of gravity not behaving the way we expect it to, outside the solar system" may be an example of how science really works In this way, the Lakatosian view of the nature of science more closely matches the behaviour of what astronomers, as scientists, do than alternative views such as those of Popper, Kuhn, or Feyerabend.
Which is a reasonable approach, except for one nagging problem: Most calculation of cosmic-scale effects contain at least three corrective factors: Relativistic expansion, CMB flow, and DE effects. DE and GR effects; if they are both wrong in a small degree, have the potential of lining-each-other-out when evaluating observations on a cosmic scale. This is one of many reasons I think we need to limit acceptable parametric effects to those which can be both modeled and tested locally.
Parametric tweaks in the cosmos should be sold as speculative, rather than dogmatized. It is better to say we do not know, than to pound square pegs into round holes and declare victory. As of today, its nature is quite uncertain. Perhaps if you clarify this, I could comment on the rest of your post.
And in any case, what does this have to do with DM which is what the part of my post you quoted refers to? Like Jerry, you seem to be under the impression that Popper would have claimed that the observational inconsistencies which astronomers explain via the dark matter theory would have led Popper to completely reject the standard model. Well, then, why did he never say such a thing? He did live well into the nineties!
I am also surprised that you seem to think Kuhn would have a problem with such a situation. I don't know his philosophy of science as well as Popper's, but it seems like he would have a straightforward explanation: everyone is doing their best to save the old paradigm, until such time as a sufficiently powerful new paradigm shows up. The first hints about dark matter henceforth DM were from measurements of the rotational velocities of stars in galaxies and of the motions of galaxies within clusters.
Everything else that was observed confirmed GR as an accurate description of how gravity works. So, you have three options: 1 throw out GR as invalid because there are two or three observations that it cannot exaplin; 2 accept that GR is not perfect, but also accept that you do not yet know how it needs to be modified; or 3 accept GR as a good theory and that the unexplained observations imply the existence of matter that has not been observed in any part of the EM spectrum.
The observations were indeed observations of gravity not behaving as expected, but astronomers did not take this as an indication that a theory that had passed so many tests and had no credible competitor was false. Instead, they inferred the existence of matter that we have not yet observed. Until a better theory comes along, GR is the best description we have of how gravity works. And that was the best explanation available until a better theory came along.
Scientists only throw out a theory in favour of a better one. What else can you do? Throw out a theory in favour of no framework at all? Simply this: the difference is years or more of astonishing scientific advancement and discovery. We know so much more about the universe and how it works than did the scientists working in the 19th century. We also have a deeper understanding of the philosophy of science, what assumptions we take as axiomatic, and how we deduce information from observations.
At least consider the possibility the primary theory is wrong; especially when auxillary theories lack supporting evidence. There should be no requirement that a new theory is sitting on the table when an old one false to satisfy observational evidence.
Why would you consider this good scientific methodology. By profession, I do a lot of reverse engineering, but sometimes the right answer is that I have no idea how this works. It would be wrong to say "until proven otherwise, this chip is just like the last one, except that they added a new output".
That's naive falsificationism, and I think the record is very clear that Popper didn't hold to that view, despite rather widespread misconceptions to the contrary including, so far as one can tell, the misconceptions held by Jerry. In this case, I was trying to say that, of the four views I cited, the Lakatosian one is a better match to the way science actually works than any other.
If you expand your criteria for deciding 'better', in terms of views of the nature of science, to include things like providing insights that permit you to go on to learn more, or the ease with which you can map your views onto the actual, observed behaviour of scientists, I'm sure you'd agree that Popper's falsificationism is definitely second best when compared to the Lakatosian research programme.
As with Popper, it's not that I think Kuhn "would have a problem with such a situation", it's that the Kuhn view of how science is done - DM and gravity in this case - isn't as good helpful, productive, provides good insights, etc as that of Lakatos. Well, in your OP, you asked about how we determine if a theory is valid.
Whatever you're doing, by suggesting that we throw out GR in favour of no framework at all, it sure isn't science! Think about it Jerry - this position would require vast swathes of science and engineering to grind to a halt At least consider the possibility the primary theory is wrong;That's more like it You've said this several times before, if not in this thread, and haven't answered my questions above - what do you mean?
Please be as specific as you can. How about "because that's the way science astronomy in this case works"? That you may not like it, or may wish that the nature of science were otherwise, or If, as your OP seems to say, you want to know how we determine if a scientific, astronomical theory is valid, then any answer must include 'there is no viable alternative'. I can't comment on what you do in engineering; your question was about science astronomy , and how it works. One ephemeris, several ephemerides eff-uh-MARE-i-deez.
Actually, I can't think of any time when a field of science was left with a refuted old theory and no new theory to replace it. When you add auxiliary hypotheses to an old theory, you end up with a new theory. What's the etymology? Are there any other words in English which form the plural in such an odd way? Jerry, I agree with Nereid on this one: science needs some kind of framework in which to interpret results and observations. This is the case even if you suspect that the leading theory is flawed.
Having a flawed theory as the best in a field is a great motivator for the theorists. One of the several things that spurred Einstein to develop GR in the first place was the fact that the Newtonian formulation of gravity could not explain several observations in particular, the observed motion of Mercury. Take particle physics as another example. The Standard Model is strongly suspected to be flawed: it does not explain the existence of the "zoo" of subatomic particles.
There are several attempts to formulate a better theory in progress, but we are still using the Standard Model, because it is the best we have at present.
The theory of creation, espoused by Newton, was certainly flawed. We could have modified the theory: Many individuals today will argue god is responsible for evolution; and that Genesis is in complete agreement with ssome variation of 'intellegent design'.
I bring this up because this was one of the choices Darwin could have made: Natural selection as an auxillary hypothesis to the intellegent creation of the first DNA. We know there are still flaws - there is no way to marry particle physics with GR.
Which of the two is 'most correct'; and how we get from A to B has been up in the air for half a century now. Therefore I do not see how the argument that auxillary hypothesis are preferable to fundamental changes are supported by either the history of science or the current state of our physical understanding of the universe.
Remember that the OP referred specifically to scientific theories i. We could have modified the theory: Since there are still several versions of "creation theory", I would argue that the "theory" was modified, but it is still not scientific because it cannot be cross-checked against reality.
Many individuals today will argue god is responsible for evolution; and that Genesis is in complete agreement with ssome variation of 'intellegent design'.
Perhaps that is so, but the OP referred to scientific theories, not faith-based ones. Actually, I think he did see it that way. There is nothing intrinsically atheistic about Natural Selection or Common Descent.
They only contradict biblical literalism, which has been shown by theologists to be a logically untenable position anyway. Many millions of people reconcile NS and CD with their faith and are quite comfortable to live thus. Yes, and many aspects of evolutionary biology have changed since Science advances. Was there a point you were trying to make here? If by "auxiliary hypothesis" you mean alterations to an existing theoretical framework, I think I can shed some light on the preference.
Over the last 20 - 30 years, our ability to make measurements of natural phenomena has increased significantly in precision. We can thus be reasonably confident that our existing theories are at the very least a close approximation of reality. There are still problems to be solved, challenges to meet, observations to confirm, predictions to test; this is why people go into science as a career well, it certainly ain't for the money!
As you point out, there is still the fundamental disagreement between quantum mechanics and GR - several theories have been proposed to reconcile the two, but we are currently unable to distinguish between them experimentally. So, there are areas of science operating in a "we don't know yet" kind of mode. This does not change the success to date of the theories we have. Without quantum physics there would have been no nuclear power or nuclear weapons and no microelectronics no transistors, no computers and so on.
GR, to take another example, has passed every test to which it has been put. It predicts the existence of black holes, and lo! The discovery of the structure of DNA opened up new ways to explore evolutionary theory; DNA sequencing has delivered a whole new way in which to build phylogenetic trees, in the process supplying a very strong confirmation of the predictions of Common Descent.
It is for these reasons that many areas of science have a strong preference for auxiliary hypotheses based on my interpretation as stated above over entirely fresh theories.
This does not mean, however, that fresh theories are not possible or likely. It simply means it is hard to work out what they might be; what shape or formulation they might take.
This is because the theories we have are good ones: we have confirmed many times over that they are at least close approximations of reality. Actually, there is no way that Darwin could have chosen this theory.
One important reason for this is that he had no concept of DNA and a limited, but operational, concept of genes. Another important reason is that the theory is not about the creation of the world but about the nature of things in the world. Darwin proposed a theory about organisms as they are observed. Whether or not their is some divine ultimate origin of initial life, this has little, if any, bearing on the observations compiled by Darwin.
The hypothesis that there was a divine creator is entirely separate from the theory of evolution. The only seeming exception is that certain observations related to evolution rule out certain kinds of creators, because the theory of a creator must be consistent with what was created. Thus it seems that Darwin could not simply have presented his work as a corrected theory of creation.
Good point, Kwalish Kid. Of course Darwin had no knowledge of DNA, and no knowledge of Mendel's work elucidating the principals of heredity. Good arguments, thank you. I do take minor exception to the Idea that 'GR has passed every test to which it has been put. I don't point this out as proof that there must be something wrong, but this negating evidence is often overlooked and ignored when sweeping statements are made about the success of GR.
Fair points, Jerry, but I suspect the detection of gravity waves is more a test of our ingenuity than it is of the theory. Having said that, if we fail to detect any gravity waves at all in the next 10 - 15 years, this will indicate that there is something wrong with GR. There is some tendency to give the words of the most prestigious scientist more weigh than lesser know opinions.
Few of us know the math, nor the background science, nor the patience to make a learned analysis of science ideas. A scientific theory is not the end result of the scientific method; theories can be proven or rejected, just like hypotheses.
Theories can be improved or modified as more information is gathered so that the accuracy of the prediction becomes greater over time. Theories are foundations for furthering scientific knowledge and for putting the information gathered to practical use.
Scientists use theories to develop inventions or find a cure for a disease. Some think that theories become laws, but theories and laws have separate and distinct roles in the scientific method. A law is a description of an observed phenomenon in the natural world that hold true every time it is tested.
It doesn't explain why something is true; it just states that it is true. A theory, on the other hand, explains observations that are gathered during the scientific process. So, while law and theory are part of the scientific process, they are two very different aspects, according to the National Science Teachers Association. A good example of the difference between a theory and a law is the case of Gregor Mendel.
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