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Author Topic: Question on the use of "Theory"
Dagonee
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One Big Bang, or were there many?

quote:
The universe is at least 986 billion years older than physicists thought and is probably much older still, according to a radical new theory.

The revolutionary study suggests that time did not begin with the big bang 14 billion years ago. This mammoth explosion which created all the matter we see around us, was just the most recent of many.

The standard big bang theory says the universe began with a massive explosion, but the new theory suggests it is a cyclic event that consists of repeating big bangs and big crunches - where every particle of matter collapses together.

"People have inferred that time began then, but there really wasn't any reason for that inference," said Neil Turok, a theoretical physicist at the University of Cambridge, "What we are proposing is very radical. It's saying there was time before the big bang."

Under his theory, published today in the journal Science with Paul Steinhardt at Princeton University in New Jersey, the universe must be at least a trillion years old with many big bangs happening before our own.

Given the discussions we've had about the use of the word "theory," especially in evolution discussions, is the use of the word "theory" appropriate here? Is there a nuance I'm missing?

Or is it likely that the article in Science didn't use that word, but the journalist did?

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King of Men
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First, I would note that the cyclic universe is hardly very new. It was proposed at least as far back as the fifties. Perhaps these guys have come up with a new variant, or (better still) some experimental evidence or at least some consequences; but the basic idea is as old as the Big Bang itself.

Apart from that, I think scientists usually use the word 'theory' in its accepted sense within that community : That is, a hypothesis well supported by the data, which has not yet succumbed to any challenge. So if it was indeed the article and not the journalist, then the writer probably meant 'theory' as a compliment rather than an attack. He's saying "Well, this opposing hypothesis is pretty strong stuff! But even so, I think I can knock it down, and here's why." If it was inserted by the journalist, then who knows? But while creationists do tend to attack the Big Bang, I think I would not assume that that 'controversy' is rearing its ugly head in a quite random cosmology article. I think it's a legitimate use of the word. If nothing else, it's not as though the cyclic universe model supports the creationist view - rather the opposite.

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ricree101
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I'm more interested in the journalist's definition of new. I've definitely heard of the general idea before, and there doesn't seem to be anything much new in this article.

I'd say that there definitely is some poor reporting here. Either they left out key details that really make this something new, or it is being given a lot more significance than it probably deserves.

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Xavier
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This can't be all that new, I've heard about possible cyclic "crunches" and "bangs" for years. I'd thought that it had been largely discredited in the 90's.

quote:
Given the discussions we've had about the use of the word "theory," especially in evolution discussions, is the use of the word "theory" appropriate here? Is there a nuance I'm missing?

I can't pretend to be an authority, but to me this is a case of overusing a term. In my mind, the Theory (with a capital T) of evolution is that species are created through random mutations and natural selection. The theory (with a little T) that the first organism evolved from heterotrophic molecules is not the part of evolution that earns it its Theory status.

Now, in regards to the Big Bang, also in my mind, the Theory (captial T) is that all matter in the universe once occupied a single point, and diverged in an great explosion. The added theory (little T) that time originated at this point, is not something which is included in the Theory.

If that makes any sense [Wink] . Now someone can come in and give you a better answer...

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Shigosei
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Judging from the abstract, I'd guess that "model" might be a better term.
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Dagonee
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KoM, my question actually had nothing to do with creationism or its relationship to the Big Bang, nor did I think it was an "attack" on the article nor did I think there was any controversy. Rather, I was asking if the more relaxed use of the word "theory" which is evident here is accepted amongst scientists.

The standard response to "Evolution is only a theory" is "Gravity is only a theory." The fact that two contradictory hypotheses can rightly be called theories seems to dull the rhetorical effect of that rejoinder.

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King of Men
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Oh, but hang on - both models are referred to as theories. That makes it more likely to me that this was inserted by the journalist. The cyclic stuff hardly deserves that status yet, it's more of a 'conjecture'. But still, since he treats them as being on an even footing, it's unlikely he intended it as an attack; he probably just doesn't realise what a theory is.

Edit : I wrote this while Dag was posting the above.

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Dagonee
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quote:
Oh, but hang on - both models are referred to as theories. That makes it more likely to me that this was inserted by the journalist. The cyclic stuff hardly deserves that status yet, it's more of a 'conjecture'. But still, since he treats them as being on an even footing, it's unlikely he intended it as an attack; he probably just doesn't realise what a theory is.
OK, that's what I was wondering.
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twinky
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I agree with KoM's 4:17 post. Also, "hypothesis" would be a suitable drop-in replacement to correct the problem.
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The Pixiest
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Ya I thought the Big Crunch was discredited in the 90s too. That in a trillion trillion trillion trillion .... trillion trillion trillion years matter would be scattered without the gravity to crunch back down.

Pix

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Baron Samedi
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There's an idea among many people that an hypothesis is a completely unproven idea which, once it passes certain tests, graduates to being a theory. Then once the theory passes its tests, it graduates to the status of law. There are several definitions of theory, but this isn't the one that scientists use.

According to my understanding, a law is something that is observably true, such as gravity or thermodynamics. When trying to explain how a law works, people come up with individual ideas that can be tested, which are called hypotheses. Once people test enough hypotheses to gain some kind of broad idea that explains how a law works, they can form these ideas into a picture, called a theory.

From this point of view, calling something a theory isn't saying it's better than an hypothesis or less reliable than a law. After all, atomic theory and the theory of relativity, which are fairly universally accepted, aren't laws. It's not that they're unreliable or controversial, it's just that they describe a different type of idea that doesn't fall under the definition of "law".

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King of Men
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That's an interesting way of looking at it, and I wish it were true, but it ain't so. A 'Law' is just what they called a theory back in the nineteenth century, when people tended to be a bit more bombastic on how good Progress and Science was for the human race, especially the white part; and also before Popper and Kuhn did their work. So Einstein's "Theory" of general relativity is actually more accurate than Newton's "Law" of Gravity, but they both describe the same thing, namely that things tend to stick to the earth unless you push 'em.
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Baron Samedi
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quote:
Originally posted by King of Men:
So Einstein's "Theory" of general relativity is actually more accurate than Newton's "Law" of Gravity, but they both describe the same thing, namely that things tend to stick to the earth unless you push 'em.

Actually, you're thinking of Newton's laws of physics. You are right, though, the definitions have evolved over time. Nevertheless, a "law" doesn't have to be complete, just accurate within whatever parameters it sets up.

In any case, my point is that there isn't the stepwise hierarchy relating hypotheses, theories and laws that most people assign to them.

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rivka
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quote:
Originally posted by Baron Samedi:
Actually, you're thinking of Newton's laws of physics.

Pretty sure he's referring to Newton's Law of Universal Gravitation, actually . . .
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Will B
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I would say "theory" is a perfect word. So are "explanation," "hypothesis," and "model."
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Orincoro
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quote:
Originally posted by Dagonee:
quote:
Oh, but hang on - both models are referred to as theories. That makes it more likely to me that this was inserted by the journalist. The cyclic stuff hardly deserves that status yet, it's more of a 'conjecture'. But still, since he treats them as being on an even footing, it's unlikely he intended it as an attack; he probably just doesn't realise what a theory is.
OK, that's what I was wondering.
Stephen Hawking writes extensively on his use of the word "theory" in "A Brief History of Time."

The proper use of the word eliminates a wide range of suppositions and conjecture. An idea can't be a theory for instance, if it can't be used to make observable predictions about the nature of the universe or interactions within it. This probably isn't a theory because it doesn't seem to provide any useful outlook on cosmic events. Its just a supposition who's consequences haven't been provided for: a hypothesis perhaps.

Theories in science are actually closer to what most people call plain facts or laws. A theory in common use is usually supported by alot of observation, and is as close to true as science is likely to get in that field.

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Tresopax
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I would say a theory, in a general sense, is simply any proposition that is backed up by some sort of reasoning. It's a very broad concept - it can cover anything from the Theory of Evolution to someone's personal theory that aliens abducted him. I think this is what people are thinking of when they normally use the term "theory".

In science, there is a more technical usage. Science requires that the reasoning supporting the "theory" be pretty strong and scientific in nature. In practice, however, I think it often boils down to "Something is a theory if a large enough number of qualified scientists back it, and something isn't if few or no qualified scientists back it" because there is no clear way to define what evidence constitutes strong enough.

I dislike this technical usage because it invites conflict for no good reason. What is strong enough evidence is debateable. Who is qualified to declare something well-supported is debateable. Thus, the same proposition can be a theory to one person and not a theory to someone else. And the only reason one would care about what is truly a "theory" and what isn't is if one wanted to elevate certain propositions in scientific discussion above certain others. I don't think science needs to be in the business of using semantics to make such distinctions. Instead, there should be perfectly good scientific explanations, rather than semantic arguments, to explain why one proposition is elevated above others by scientists. So there is no need to make "theory" into such an exclusive term.

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Orincoro
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quote:
Originally posted by Tresopax:
I would say a theory, in a general sense, is simply any proposition that is backed up by some sort of reasoning. It's a very broad concept - it can cover anything from the Theory of Evolution to someone's personal theory that aliens abducted him. I think this is what people are thinking of when they normally use the term "theory".

I dislike this technical usage because it invites conflict for no good reason. What is strong enough evidence is debateable. Who is qualified to declare something well-supported is debateable.

I'm sorry but the "its all relative" argument doesn't cut any ice in the real world. There needs to be a very strict standard, and a demarcation between what is theory and what is supposition. In science "theory" is closer to fact than to anything suppositional. Yes, lay usage allows for "theories" which are really only unsupportable ideas, but that doesn't make this ok in the scientific realm. The thing is, we need a word for what is in all practical terms fact, but which can not be inconclusively proven.

Scientific theories can only be dispoven, whereas the lay usage of the word assumes that a theory needs proving. That's simply not the way science works, and I think you aren't taking that into account. Theories are shaped by everything that is not possible, and a good theory makes predictions based on what is proven not to be true. The goal is to eliminate all inadequate theories until one theory stands uncontravertable, because it perfectly describes the universe. You can't go to the end and explain everything all at once, then prove it. You have to develop a series of seperate theories and then derive your final picture from those few that stand up to investigation.

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Destineer
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quote:
Apart from that, I think scientists usually use the word 'theory' in its accepted sense within that community : That is, a hypothesis well supported by the data, which has not yet succumbed to any challenge.
A couple of people in this thread have made claims similar to this one. I must disagree.

A theory in science is just a statement, or a bunch of statements, about how the world is. Some theories are accepted by scientists, which typically means they have good experimental support. Some theories are never accepted, and some are set aside or rejected. No one believes Newtonian mechanics any more, but it remains a theory nonetheless.

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Tresopax
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quote:
There needs to be a very strict standard, and a demarcation between what is theory and what is supposition.
Why? What's wrong with just saying some theories are well-justified by evidence and others are not?

quote:
The thing is, we need a word for what is in all practical terms fact, but which can not be inconclusively proven.
Perhaps such a word is needed, but a theory is definitely not something that is in all practical terms fact. This is proven by the following:

-Disproven theories are still called theories, even in science.
-There are often different theories that answer the same scientific question with different explanations. Both of them could not be fact.

Hence, it is incorrect to say that a theory is in all practical terms fact.

quote:
Scientific theories can only be dispoven, whereas the lay usage of the word assumes that a theory needs proving.
That is what separates SCIENTIFIC theories from other theories, not what separates theories from non-theories.
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King of Men
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quote:
Originally posted by Destineer:
quote:
Apart from that, I think scientists usually use the word 'theory' in its accepted sense within that community : That is, a hypothesis well supported by the data, which has not yet succumbed to any challenge.
A couple of people in this thread have made claims similar to this one. I must disagree.

A theory in science is just a statement, or a bunch of statements, about how the world is. Some theories are accepted by scientists, which typically means they have good experimental support. Some theories are never accepted, and some are set aside or rejected. No one believes Newtonian mechanics any more, but it remains a theory nonetheless.

You seem to be making a statement about how you think science ought to be. I do not think it describes what scientists really do. I for one would not refer to Newtonian physics as a theory; it is a model, a method, or an approximation. Or, more commonly, just 'Newtonian physics'. I have certainly never heard anyone refer to it as a theory.

Now, against this, it must be said that we don't usually bother with distinctions like that while actually working, anyway. I've heard people say things like "Well, suppose we just look at it with straight Newton, and see what happens." Or again, "Ok, that makes no sense, suppose we try Einstein?" Conversely, in papers, people will say things like "We use a lattice model of the strong interaction" or "in the heavy-quark-field approximation" or "assuming full SU(3) symmetry" - these latter three are models. While on the other hand, the Quantum Field Theory that they are based on is a full-fledged theory, we just can't solve the math.

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JonnyNotSoBravo
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quote:
Originally posted by Destineer:
Some theories are never accepted, and some are set aside or rejected. No one believes Newtonian mechanics any more, but it remains a theory nonetheless.

Actually, most scientists do believe in Newtonian mechanics. It's taught in virtually every beginning college level physics class. It is definitely not set aside or rejected. It is adjusted when approaching "relativistic" speeds by changing the formula slightly. Newtonian mechanics is definitely "correct", i.e. it gives reliable predictions, for most lower velocities. In some cases, Einstein's theory gives much better results, like it "explained slight alterations in Mercury's orbit around the Sun."
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King of Men
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I think you are using different definitions of 'believe in'. Believe that it is a useful approximation, sure. That's what you are describing. Believe that it really is the way the world works, no. That's presumably what Destineer meant.
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JonnyNotSoBravo
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Well, Einstein's theory is an approximation as well, it's just better than Newton's in cases. It is not exact in a lot of cases. I think using the "believe in" definition that you presume Destineer to have meant is a poor means of communication. I was trying to clarify that physicists still use Newton's formulas very often.
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King of Men
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Hang on, in just what cases is Einstein not exact? I ask this out of sheer greed, you udnestand, because I'd purely love to get that trip to Stockholm for publishing such data.
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fugu13
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KoM: the sufficiently small ones [Wink]
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Orincoro
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From what I remember in my science readings, General Relativity and quantum theory provide different views of the universe, and don't always agree on answers.

Tres- my point with my post was to quell an instinct to say: "everybody is right in varying degrees, and we can't judge." This is a ludicrous worldview that was forced upon me, and probably many American kids as a child, and I see it crop up all the time. The thing is that some ideas are stupid and some are good, and I think science aught to have primacy over what it wants to call a good idea. Science can't go injecting alot of TLC into its treatment of obviously dodgy ideas.

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JonnyNotSoBravo
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Link from above:
quote:
In 1960, Robert V. Pound and Glen A. Rebka demonstrated that a beam of very high energy gamma rays was ever so slightly redshifted as it climbed out of Earth's gravity and up an elevator shaft in the Jefferson Tower physics building at Harvard University. The redshift predicted by Einstein's Field Equations for the 74 ft. tall tower was but two parts in a thousand trillion. The gravitational redshift detected came within ten percent of the computed value. Quite a feat!
Not exact, unlike the slight alterations in Mercury's orbit which were exact.
quote:
In the 1960s, a team at Princeton University measured the redshift of sunlight. Though small, given the Sun's mass and density, the redshift matched Einstein's prediction very closely.
Not exact.

Of course, both of these have to do with measuring redshift, and possibly we do not have sensitive enough equipment to measure it accurately.

Both of these were published in the 60s, so I doubt you will get any money from Stockholm.

Source:
quote:
However, minuscule deviations from the laws of relativity could arise in an underlying theory that unifies gravity with quantum physics. Observable signals from these relativity violations are governed by a theory called the Standard-Model Extension.
Not a very good link. But it hints at deviations. I'll keep searching.

From Wikipedia:
quote:
Some physicists think dark energy (energy density of virtual particles) is an indication of a failure of general relativity on the large scales, perhaps due to the effect of living on a brane (Dvali, 2000), or due to other corrections to the Einstein field equations.

Other physicists think dark matter is an indication of a failure of general relativity on galactic scales, and that the observed flat galactic rotation curves are due to a theory of Modified Newtonian dynamics or a relativistic variant, such as the TeVeS theory of Bekenstein. Some physicists point to the Pioneer anomaly as evidence of the failure of general relativity. This is not the view of most cosmologists, however, who think that the rotation curves are best explained by cold dark matter.

So relativity seems to fail when using large galactic scales, perhaps similar to how Newtonian mechanics seems to fail at very high velocities. Perhaps general relativity needs to be adjusted for those large scales, just as Newtonian mechanics is adjusted for high speeds. This is a Wikipedia link, so feel free to take issue with it.

I have no doubt that you are better at physics than me, KoM! I bow to your superior knowledge in this area. I am betting we are arguing over semantics.

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JonnyNotSoBravo
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quote:
Originally posted by fugu13:
KoM: the sufficiently small ones [Wink]

Well, from the link I just posted above, it actually might be the sufficiently large ones. [Wink]
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King of Men
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You are completely misunderstanding the 'very closely' and 'within ten percent'. That's not errors in Einstein, that's experimental uncertainty. The rest is either hypothetical - 'could arise' - or sufficiently explained by cold dark matter.
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fugu13
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JNSB, you are misunderstanding what the difference between exactly matching measurements and being an approximation is.

Due to the inability to compute every factor affecting something, even a perfect theory will often result in computations not matching reality, because the computations we make based on the theory don't try to take in every possible effect; that would be futile.

This is different from what it is meant for a theory to be an approximation. A theory is an approximation if we are confident the theory does not reflect the reality of things. For instance, we know Newton's equations do not reflect the reality of things, so they are approximations. Einstein's theory, however, appears to be pretty much a correct characterization of reality.

This does not mean we expect every experiment to exactly match the outcomes of the idealized experiment calculated mathematically, but that we expect outcomes of real experiments to almost always have the theoretical outcome within some reasonable confidence interval of the actual one.

With relativity theory, they do (where relativity theory is applicable under its assumptions).

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JonnyNotSoBravo
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Actually, I did understand that which is why I posted about not having sensitive enough equipment might be the reason behind not being exact. What I have a hard time distinguishing is the difference between experimental uncertainty and whether a theory is "exact" enough. Newton's theories were exact enough for a long time. The question I have is: Will Einstein's theory be "exact" enough for a long time until someone comes up with something better and the theory gets adjusted once again?

Edit: Yes, Einstein's theories appear to "explain" things better than Newton. I think someone will come up with something that supercede's Einstein's theory, just as Einstein's superceded Newton's. All theories are just mediating representations, IMO, of reality. Some are better repesentations than others.

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fugu13
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JNSB: at this point that's all speculation. There are explanations perfectly consistent with relativity theory. We're constantly aware that theories might be incorrect, that's no surprise at all, and that incomplete real-world data can often be confounding, also no surprise at all. This can lead to the formulation of new theories and the testing of new and old theories, but in and of itself confounding incomplete data doesn't mean much for relativity at all. Its not even remotely close to a demonstration that relativity theory is an approximation.
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fugu13
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No, you're continuing to misunderstand. It has nothing (usually) to do with the sensitivity of equipment, but with the fact we can't calculate everything. There are incredibly huge numbers of things impacting the outcome of any real life experiment, but we can only calculate the effects of a very small number of them, the ones most affecting the outcome (well, at least so we hope). Even if the calculations we do are accurate and based on a perfect theory, they are done by assuming a simplified worldview that only accounts for some small number of the effects. Any experimental result will thus be off by some factor. A good theory, of course, will be able to tell us on approximately what order those effects occur. That, combined with statistical notions of uncertainty, allows us to state whether or not experimental results are consistent with a theory with various degrees of certainty.

And its not really about adjustment, either. Einstein's theories are completely different from Newtonian mechanics, which Newtonian mechanics closely approximate at non-relativistic speeds. There was no adjustment, there was the wholesale creation of new theory.

As far as we know, there is no need for a new theory to replace relativity (well, one that unified relativity with other theories would be nice, but for the domain it works in under its assumptions we don't need a replacement). If we ever find a class of results that regularly have confidence intervals the theoretical results fall outside, then we'll need a new theory.

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JonnyNotSoBravo
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Ah, we're mired in semantics again. Approximation to me does not mean "if we are confident the theory does not reflect the reality of things". To me, it is impossible to determine the "reality of things" because it is processed through the filter of our senses and intellect. All we can do is get higher and higher predictive accuracy regarding what we observe and interact with. We can achieve this accuracy but still be completely wrong about how the world works. That won't matter to us however, because the predictability is what, IMO, we desire to do things and make things work.

Edit: the "adjustment" I was referring to was (in my head)given by an example of how to calculate mass at high velocities using Newtonian equations. You just adjust the equation by adding in a relativistic factor. I understand that the approach was entirely different, that Einstein's general relativity theory reached much farther than just adjusting Newton's theories, and gave us a new paradigm for looking at the universe.

This is all philosophy, though, and is probably not where you wanted to go.

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King of Men
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As an aside, for tests of GR, I do think experimental error will always be the dominant uncertainty. There are several areas of particle physics where theoretical uncertainties dominate, but GR is highly calculable, if that's a word. That is, we know what we ought to get, pretty much.
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fugu13
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quote:
To me, it is impossible to determine the "reality of things" because it is processed through the filter of our senses and intellect.
This is not a question of semantics, but an epistemological position. My semantics are completely valid, but of course given a philosophical position that no theory will really reflect you're unwilling to accept a particular theory reflects the world. That is a valid perspective, it just isn't especially useful.
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Dagonee
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Just a quick note: I believe my original question was answered, but I'm enjoying the ongoing discussion. I simply have nothing to contribute to it.
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JonnyNotSoBravo
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quote:
Originally posted by fugu13:
quote:
To me, it is impossible to determine the "reality of things" because it is processed through the filter of our senses and intellect.
This is not a question of semantics, but an epistemological position. My semantics are completely valid, but of course given a philosophical position that no theory will really reflect you're unwilling to accept a particular theory reflects the world. That is a valid perspective, it just isn't especially useful.
Oh, there was definitely a question of semantics in there. I don't doubt the validity of your semantics because I think others share that view of what "approximation" means. To me, approximation just means trying to approach 100% predictability, but it might not get there.

I mixed in philosophy to explain why the word meant something different to me. I think the view is useful because when using that view it is easy to embrace something that sounds silly as long as it has great predictability. This would eliminate the bias of "intuition", while allowing intuition to still guide you to areas of great predictability.

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Orincoro
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JNSB, I'm afraid science does quite a bit more than what you suggest.

Your view seems useful to you, but look at what your saying "it is easy to embrace something that sounds silly as long as it has great predictability."

Under that schema I could just as easily wedge in alot of useless rules and ideas that don't effect outocome, and that have no bearing on reality. I would get a whole giant list of predictions, and just because a few of them would be right, that wouldn't make my theory useful in any way.

For instance if I could adopt any theory to predict outcome and that theory would be valid, then I could simply say that God decided that the universe would do everything that the universe is now doing. This is not a scientific position because it is molded to fit the facts. Though it predicts that the universe will continue on as it does, the fact that the universe continues on until next year has not proved that God did it, scientifically speaking.

My point, though I am having difficulty relating it, is that your view of what is acceptable in the realm of theory is top heavy with the vagaries of human interactions. You need to make a specific prediction, and ascribe a specific cause. Even then the outcome will be affected by other factors which you must account for, or call your theory wrong. Either way there is not going to be a perfect large statement to account for all small effects, and even if there is, that large statement could be anything, since it wouldn't help you understand the world around you any better than you already do.

edit: Although there have been a few instances in history where human understanding of the universe has lept ahead at an unprecedented rate based on the intuition of a single mind, those are special cases and are far outweighed by the number of times an idea has occured to someone, and been proven wrong almost immediately. Just because Newton and Einstein came up with brilliant theories in moments of unexpected insight, that doesn't mean this is the way you should approach everything you do. Those are the rare moments that the creative mind invents something radical, which turns out to be correct almost by sheer coincidence. Newton himself was so much in shock when he saw that his calculations on gravity were turning out correctly, that he couldn't even hold his pen to write them down.

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fugu13
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As prominent modern theories explicity exclude the possibility of 100% predictability, I think your view on predictability is likely inherently flawed [Smile]
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King of Men
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Predictability is a fine thing, but not everything. Consider the 'theory' of physics that simply consists of a list of everything we have ever observed. The boiling point of water is this, the temperature of star X is that, the diameter of the Earth is so much. It perfectly predicts everything that is known about physics; but I think you'll agree that it's not much of a theory.
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JonnyNotSoBravo
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quote:
Originally posted by fugu13:
As prominent modern theories explicity exclude the possibility of 100% predictability, I think your view on predictability is likely inherently flawed [Smile]

Yes, quantum theory, whether an electron is a particle or a wave, the position of a particle, etc. Probability removes the possibility of 100% predictability. But we predict the odds! [Wink]
quote:
Originally posted by King Of Men:
Predictability is a fine thing, but not everything. Consider the 'theory' of physics that simply consists of a list of everything we have ever observed. The boiling point of water is this, the temperature of star X is that, the diameter of the Earth is so much. It perfectly predicts everything that is known about physics; but I think you'll agree that it's not much of a theory.

But does it predict new things? You can have everyday predictability, like the confidence you have that gravity will still work today. That's called experience. In that way, every child and person is a scientist. The rat who remembers its way through a maze is a scientist. Learning those things is a part of science and does contribute. Like the observation of animals in their habitat - definitely science. Recording what we know of the world around us is definitely science.

But you're talking about figuring out whether a theory is valid. That seems to be done by proposing tests that have never been done before but will have predictable results based on theory and calculations. What's true is based on predictability. If it isn't predictable, the theory is either set aside or adjusted. Predictability can be both what is observed and what has not been.

Think about what people thought was reality: the earth was the center of the universe, electrons act only as particles, there's nothing smaller than an atom. Now we think the universe is made up of STRINGS?! That seems fairly absurd. Electrons act as a particle OR a wave?! Very counterintuitive. What makes us think those ideas are real? Predictability. Didn't we observe those "strings" before they were strings, then find a formula (by flipping through a book) that matched that pattern?

My observation about 100% predictability was a little too flip, as fugu pointed out. [Smile]

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JonnyNotSoBravo
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King of Men, you seem to be hinting that science is more, that it explains WHY. I'll give you an example that might show why I avoid that thinking:

A biologist will watch a bird singing and think, oh it does this to find out where other birds are, to find a mate.

The bird might think I sing because it feels good, or because I like to hear the song.

Why do people sing when they are alone?

I'm not saying we should anthropomorphize animals. I'm saying that, IMO, science often oversteps its bounds when it tries to explain WHY. Yes, the birdsong might have the effect of attracting mates, finding other birds who sing back and warning others. Yes, it might have evolved that way because of those effects. But it might not be why the bird is singing.

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King of Men
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quote:
But does it predict new things?
Well, that's just what I'm saying - predicting a bunch of stuff is good, but it has to do so in the right way.

As for why, I don't see where I said any such thing; but I also think the biologist's explanation was perfectly valid.

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JonnyNotSoBravo
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Orincoro,

I'm having trouble responding to you because your objection seems vague. If religion offered greater predictability than science, I might accept those parts of it that predict things well and avoid the rest. Something that is molded to fit the facts is obviously not being predictive because it was formed afterwards. Predictions based on experience (even religious experience) are still valid if they come true and are independently verifiable. If you can get all those predictive experiences without religion, that would seem to be better wouldn't it? Less hassle.

You can account for different factors rather easily. Call it an X or Y factor, make up a name for it, say it skews the predictability on these occasions. Limited predictability is still an improvement over no predictability. Look at meteorology (the study of weather).

I can sort of see what you're getting at. If, for example, I prayed to the statue of the Virgin Mary and blood ran from her eyes every time I did, I might think God did it, and that it was a predictable response to my piety. Praying to the statue means that blood will run from Mary's eyes. But then I might find out that a man, watching me pray, activated a pump inside the statue to make blood come out. Yet believing that praying would cause blood to come out of Mary's eyes was correct. After finding out about the man and the pump, I change my theory. Because I subscribe to a theory does not mean I shouldn't question it. Science is about questioning things, IMO.

Sometimes "God" is a "deus ex machina" (I love puns), a stand-in for a mechanism we don't understand. In that sense, God can be very scientific.

I haven't found a religion so far that has been more predictive than science, or that adds more predictability to science.

[ May 06, 2006, 10:24 PM: Message edited by: JonnyNotSoBravo ]

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JonnyNotSoBravo
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quote:
Originally posted by King of Men:
As for why, I don't see where I said any such thing; but I also think the biologist's explanation was perfectly valid.

I said that you seemed to be hinting at it, or at least something MORE. Sorry if you were not! [Smile] I agree that the biologist's explanation is valid, but I think the bird's explanation is valid as well. I think when people study the sciences and are told, "this is why such and such happens" they may think of it as the ONLY correct explanation of why it happens. So I avoid the "why" and just think about the effects.
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Glenn Arnold
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There is also a difference between a theory, and the theory of a particular discipline.

Examples of this would be number theory and music theory. Both of these are collections of conventions, each of which reliably produce results within a certain framework. Rather than a single explanation of a phenomenon, these could be considered toolboxes.

Utilizing music theory for example, does not predict a result, but allows a musician to produce something that can be reliably called music (even if it's uninspired). Number theory merely provides conventions that allow mathematicians to produce results that are directly comparable to each other. 1+1=2 is not so much proven to be true as it is defined to be true. That's rather different from the way we treat scientific theories.

However, you get into a grey area, for example, when you discuss "the theory of evolution" and "evolution theory." The two are closely related, but they are not the same thing. In fact, what we usually are referring to when we say "the theory of evolution" is actually "the law of natural selection," which, along with "the law of recombination," and "the law of mutation," are the primary components of evolution theory.

Does this muddy things up or does it clarify?

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Orincoro
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quote:
Originally posted by JonnyNotSoBravo:


Sometimes "God" is a "deus ex machina" (I love puns), a stand-in for a mechanism we don't understand. In that sense, God can be very scientific.

What? My whole point was to say that you can't create a catch-all theory because the predictions it makes will be to broad. Essentially saying "God did it" is like saying "it happened because it happened." This might as well be true but it is completely non-useful in any way. It is very UN-scientific.
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Dagonee
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quote:
This might as well be true but it is completely non-useful in any way.
That's not true. It's not useful to science, but it very well can be useful in other ways.
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