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Hale_Bopp
2002-Feb-20, 06:55 PM
This is a lengthy "Survey of the Universe" from the Economist.

http://www.economist.com/surveys/displaystory.cfm?story_id=922278

Rob

DJ
2002-Feb-22, 12:08 AM
I get nervous any time I see the words priest and physics used near each other. Herbert Butterfield has some interesting points on the topic. Recommend ESSAYS ON THE HISTORY OF SCIENCE

Argos
2002-Feb-22, 10:45 AM
Yeah, It sends shivers down my spine. I don't like this thing 'bout priests and myths. Einstein was not a priest in any sense. He was only (according to himself) a curious guy seeking some order for the things. His religion was the feeling of reverence before the beauty of the cosmos - the Spinoza's God. And there's nothing mysterious in it!

ljbrs
2002-Feb-26, 12:19 AM
I never mix science with religion.

ljbrs /phpBB/images/smiles/icon_smile.gif /phpBB/images/smiles/icon_confused.gif

odysseus0101
2002-Feb-26, 02:02 AM
On 2002-02-25 19:19, ljbrs wrote:
I never mix science with religion.

ljbrs /phpBB/images/smiles/icon_smile.gif /phpBB/images/smiles/icon_confused.gif


Of course, it has also been suggested that science is a religion, in various ways. For example, faith in a correspondence theory of truth that can never be falsified.

Azpod
2002-Feb-26, 10:28 PM
On 2002-02-25 21:02, odysseus0101 wrote:

Of course, it has also been suggested that science is a religion, in various ways. For example, faith in a correspondence theory of truth that can never be falsified.


I thought that falisifiability (if there is such a word) is at the core of what makes science science. If I could tomorrow create a perpetual motion machine that actually worked, I could disprove the laws of thermodynamics, and that would require all of known physics and chemistry to be rethought.

Believing that a God created the universe 30 seconds ago is a non-falsifiable theory. That doesn't mean it couldn't be true, but it does mean that is not scientific, because there is no way to construct an experiment to prove that the universe is in fact older than 30 seconds, because I can always claim that whatever you are observing was just the initial state of the universe.

That's the reason that religion and science have problems mixing: religions tend to be non-falsifiable beliefs, and science deals with creating a self-consistent set of theories to explain all known observations. In order to be self-consistent, these theories have to be able to predict the behavior of objects. When it can't, then the theories need to be examined so that they are consistent with the new observations.

ljbrs
2002-Feb-27, 02:06 AM
I still insist that I do not believe in mixing science with religion. Ever...

ljbrs /phpBB/images/smiles/icon_biggrin.gif /phpBB/images/smiles/icon_smile.gif /phpBB/images/smiles/icon_wink.gif

MongotheGreat
2002-Feb-27, 05:00 AM
The very fact that religion requires a belief in something with absolutley no proof separates science from religion for everyone, right?

SeanF
2002-Feb-27, 01:09 PM
I think that the point Odysseus was trying to make is that the idea that you can actually discover the truth about the universe (or whatever) by ignoring any non-falsifiable possibilities (IOW, through the scientific method) is itself inherently non-falsifiable and non-provable, and thus must be taken "on faith."

I think that those who are able to remain both "scientific" and "religious" are those who accept that science doesn't necessarily tell us the absolute underlying truth about the physical world, but it does tell us all we can objectively know about it, and it does provide us with functional "models" we can use in our interactions with the physical world.


_________________
SeanF


<font size=-1>[ This Message was edited by: SeanF on 2002-02-27 08:11 ]</font>

odysseus0101
2002-Feb-27, 11:37 PM
On 2002-02-27 08:09, SeanF wrote:
I think that the point Odysseus was trying to make is that the idea that you can actually discover the truth about the universe (or whatever) by ignoring any non-falsifiable possibilities (IOW, through the scientific method) is itself inherently non-falsifiable and non-provable, and thus must be taken "on faith."

I think that those who are able to remain both "scientific" and "religious" are those who accept that science doesn't necessarily tell us the absolute underlying truth about the physical world, but it does tell us all we can objectively know about it, and it does provide us with functional "models" we can use in our interactions with the physical world.


_________________
SeanF


<font size=-1>[ This Message was edited by: SeanF on 2002-02-27 08:11 ]</font>


Thanks for clarifying my point for me, SeanF. That is basically what I meant. Furthermore, there is always the difficulty of proving that what we can perceive (test, etc.) actually tells us something about some Objective World Out There. The overly simplistic version of this is the 18th century argument about "when I see yellow, where is the yellow? Is it in the Object [used in the technical philosophical sense] or is it in my mind?" The more serious version of this difficulty is concerned with - as SeanF pointed out - accessing the actual structure of some Objective Existence.

Please allow me to get literary for a moment: Science is a self-referential text, just like any other text, and is therefore characterized by an internal play of signification without correspondence to an exogenous Truth.

Then someone says, "yeah, well then that applies to what you said, too, so you can't say anything Objective that has true Correspondence with Reality either."

Then I say, "You speak The Truth," and go get a sandwich.

Thargoid
2002-Feb-28, 12:46 AM
Here's a philosophical pretzel:

Perhaps science itself, as defined above, is not a well-defined set. Sort of like B. Russel's example of the set of all sets that do not contain themselves. Is this set a member of itself as well?

Hmmm.... /phpBB/images/smiles/icon_smile.gif

<font size=-1>[ This Message was edited by: Thargoid on 2002-02-27 19:48 ]</font>

GrapesOfWrath
2002-Feb-28, 01:14 AM
On 2002-02-27 18:37, odysseus0101 wrote:
Please allow me to get literary for a moment: Science is a self-referential text, just like any other text, and is therefore characterized by an internal play of signification without correspondence to an exogenous Truth.

And it's hard to go wrong with these two guys: Physicial concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world. In our endeavor to understand reality we are somewhat like a man trying to understand the mechanism of a watch. He sees the face and the moving hands, even hears its ticking but he has no way of opening the case. If he is ingenious he may form some picture of the mechanism which could be responsible for all the things he observes but he may never be quite sure his picture is the only one which could explain his observations. He will never be able to compare his picture with the real mechanism and he cannot even imagine the possibility of the meaning of such comparison. (Albert Einstein and Leopold Infeld, The Evolution of Physics)

2002-Feb-28, 11:43 AM
<a name="20020228.5:09"> page 20020228.5:09 aka Search4 [INLINE]
On 2002-02-26 21:06, ljbrs wrote:
I still insist that I do not believe in mixing science with religion. Ever...

ljbrs /phpBB/images/smiles/icon_biggrin.gif /phpBB/images/smiles/icon_smile.gif /phpBB/images/smiles/icon_wink.gif

[/quote]
ok so i'll attempt to link in to this page
FROM lunar Con or Against
in the next day or so { my appologies }

DJ
2002-Feb-28, 04:26 PM
And it's hard to go wrong with these two guys: Physicial concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world. In our endeavor to understand reality we are somewhat like a man trying to understand the mechanism of a watch. He sees the face and the moving hands, even hears its ticking but he has no way of opening the case. If he is ingenious he may form some picture of the mechanism which could be responsible for all the things he observes but he may never be quite sure his picture is the only one which could explain his observations. He will never be able to compare his picture with the real mechanism and he cannot even imagine the possibility of the meaning of such comparison. (Albert Einstein and Leopold Infeld, The Evolution of Physics)


I see myself in the mirror every morning, and think of how handsome I am. Yet everyone around remarks that I am hideous. How could we both be right?

The notion that being inside of something limits our ability to understand it puts science then in the realm of philosophy... it is non-falsifiable.

Azpod
2002-Mar-01, 05:38 AM
On 2002-02-28 11:26, DJ wrote:
The notion that being inside of something limits our ability to understand it puts science then in the realm of philosophy... it is non-falsifiable.


Quite untrue; it merely limits the degree to which it is falsifiable. I can create a theory on how the watch works which fails to predict the watch's behavior, or fails to hold up when I examine the face of the watch in more detail. Such a theory is falsifiable, and is this scientific. However I can create another theory that states that there exists a being that enables the watch to behave exactly as it does.

That theory is not falsifiable, and is thus not scientific. A scientific theory must be able to predict future behavior, and if it fails to do so, then the theory is false. The theory of the being who makes the watch behave exactly as you observe it can explain any new observations, but can predict none of them. Thus, it is not falsifiable, and is not scientific. That's not to say that such a being could not exist, but that the theory of this being holds no bearing on determing the inner workings of the watch, unless it can predict its future behavior.

That's not to say that all religious or philisophical theories aren't scientific. There could be a theory that all airplanes work because God causes lift across all horizonal surfaces proportional to the surface area and wind speed. This theory is scientific, religious and falsifiable. It also happens to be quite false. Many theories of how the mind worked in the 19th centure were rooted in philosophy, not science. Yet most of them were scientific, and the proof of that is that many of them were later proven to be false.

DJ
2002-Mar-01, 05:47 PM
The theory of the being who makes the watch behave exactly as you observe it can explain any new observations, but can predict none of them. Thus, it is not falsifiable, and is not scientific.


I disagree 100%

And my argument will never succeed with your mindset, so I will disagree, and will pursue no further.

Azpod
2002-Mar-01, 06:46 PM
On 2002-03-01 12:47, DJ wrote:


The theory of the being who makes the watch behave exactly as you observe it can explain any new observations, but can predict none of them. Thus, it is not falsifiable, and is not scientific.


I disagree 100%

And my argument will never succeed with your mindset, so I will disagree, and will pursue no further.


??? What mindset are you refering to? If you can show me how that the statement above is untrue then I will happily accept it. All I am saying is that a believer in a God can always claim any phenomenon occured b/c "God did it." Such a theory, however, makes no claim on any future occurance.

I'm not making this argument to bash religion, nor to embrace it. All I am saying is that the core of what makes science what it is is self-consistency with known observations, and the ability of predicting future observations. If you disagree on that basic premise, then we are talking about two radically different things when we are discussing science. If that is the case, please let me know so that we can discuss what is the core definition of something scientific.

I'm sorry but saying that you disagree 100% but not stating why does very little to support your argument.

Footnote: definition of "Scientific Method" from dictionary.com (http://www.dictionary.com/search?q=scientific%20method)

_________________
Lobster sticks to magnet. (http://www.solarisdx.net/features/1lm.html)
That is all.

--Azpod... Formerly known as James Justin

<font size=-1>[ This Message was edited by: Azpod on 2002-03-01 13:47 ]</font>

Wiley
2002-Mar-01, 07:05 PM
On 2002-02-27 18:37, odysseus0101 wrote:

Please allow me to get literary for a moment: Science is a self-referential text, just like any other text, and is therefore characterized by an internal play of signification without correspondence to an exogenous Truth.


Excuse me if I think this is a load of postmodernist excrement.

Science is self-referential insofar as it builds upon itself. However, its basis of observation and repeatability of experiment keeps it well grounded in reality. (Yes, science does assume an objective reality, but so does every other non-trivial philosophy. If one denies an objective reality, i.e., everything is a dream, one should stay in bed.) All this means is science tries to fit itself to reality, unlike a certain mediocre French historian.

Silas
2002-Mar-01, 07:57 PM
On 2002-03-01 14:05, Wiley wrote:


On 2002-02-27 18:37, odysseus0101 wrote:

Please allow me to get literary for a moment: Science is a self-referential text, just like any other text, and is therefore characterized by an internal play of signification without correspondence to an exogenous Truth.


Excuse me if I think this is a load of postmodernist excrement.



Somebody had to say it! Worse: I don't know what the phrase "characterized by an internal play of signification" means. I don't know what an "exogenous truth" is, either. (I suppose this might refer to the difference between "analytic" and "synthetic" statements. Shrug...)

But I *do* know what is meant by "electron," "force," "mass," "light," "mirror," etc. The terms are well-defined and clearly refer to external objects.

Science works extraordinarily well, because we're all looking at the exact same items. There is no ambiguity of translation or interpretation; there is no question of which authority has the greater power to dispense truth. In science, properly speaking, there is no authority at all! Any one of us can, for relatively little expense, go out and re-create most of the foundational observations.

Just as one example: the Bad Astronomer explained something about the refraction of light, and how the sun, at sunset, might actually be just below the horizon, but the refraction of light causes it to appear to be over the horizon. The effect is most pronounced *at* the horizon... And so, this weekend or the next, I'm going to go out with a protractor and a plumb bob and a stopwatch, and see if the angular rate of descent of the sun appears to slow right at sunset. It's an easy observation to make, and I want to do it for fun. (NOT because I doubt the BA's word!)

Then again, I live near the coastline, so maybe I'll end up measuring fog instead...

Silas

odysseus0101
2002-Mar-02, 12:24 AM
On 2002-03-01 14:57, Silas wrote:


On 2002-03-01 14:05, Wiley wrote:


On 2002-02-27 18:37, odysseus0101 wrote:

Please allow me to get literary for a moment: Science is a self-referential text, just like any other text, and is therefore characterized by an internal play of signification without correspondence to an exogenous Truth.


Excuse me if I think this is a load of postmodernist excrement.



Somebody had to say it! Worse: I don't know what the phrase "characterized by an internal play of signification" means. I don't know what an "exogenous truth" is, either. (I suppose this might refer to the difference between "analytic" and "synthetic" statements. Shrug...)

But I *do* know what is meant by "electron," "force," "mass," "light," "mirror," etc. The terms are well-defined and clearly refer to external objects.

Science works extraordinarily well, because we're all looking at the exact same items. There is no ambiguity of translation or interpretation; there is no question of which authority has the greater power to dispense truth. In science, properly speaking, there is no authority at all! Any one of us can, for relatively little expense, go out and re-create most of the foundational observations.

Just as one example: the Bad Astronomer explained something about the refraction of light, and how the sun, at sunset, might actually be just below the horizon, but the refraction of light causes it to appear to be over the horizon. The effect is most pronounced *at* the horizon... And so, this weekend or the next, I'm going to go out with a protractor and a plumb bob and a stopwatch, and see if the angular rate of descent of the sun appears to slow right at sunset. It's an easy observation to make, and I want to do it for fun. (NOT because I doubt the BA's word!)

Then again, I live near the coastline, so maybe I'll end up measuring fog instead...

Silas



I was going to respond by explaining myself further, but in all seriousness I just don't really feel like arguing about this. It would take too much energy to explain things properly, such as if any of you were to try to explain to me in a serious and accurate way many of the things you discuss on this board.

DJ
2002-Mar-05, 06:07 PM
I realized the other day that every time I wear my black jacket (it's a very nice jacket, so I wear it a lot)I never seem to get attacked by lions. I also realized that every time I went to the zoo I also had my black jacket on. I wasn't attacked there, even though I was too close to the lions.

I have come to realize that it is indeed, based on observation and testing, the fact that I wear a black jacket that protects me from lions.

I suspect that even if I was standing in the middle of the Serengetti, with a fresh pork chop hanging around my neck, as long as I wear my black jacket I will not be attacked by lions. I can't really go to the Serengetti to try this, however, as it is way beyond my means.

Get it, yet?

SeanF
2002-Mar-05, 06:30 PM
DJ, you're reaching the conclusion too early. You're not considering the fact that you are never attacked when you're not wearing the jacket, either - this would be the "control group" test.

Also, just because you can't go to the Serengeti doesn't mean nobody else can, and "science," by definition, requires results that can be duplicated by others. That, after all, is what makes it objective rather than subjective.

Wiley
2002-Mar-05, 07:14 PM
DJ & SeanF,

While the analogy is not completely sound, it does raise a valid concern. How do we know what is "true" from what "appears to be true" based on a limited perspective? The answer is two-fold: peer review and constant testing.

Going back to DJ's analogy, DJ finds that wearing your black jacket protects him from lions, but then SeanF comes along and says, "Hey, wait a minute. What about your control group?" Either his control group was eaten or DJ must find a new hypothesis. This is why peer review is so important because sometimes you're not testing what you think you're testing. I am using the term peer review to include the entire process from bouncing ideas off collegues over lunch to the formal review process for technical journals.

The second and perhaps most important, keep testing. Again heading back to the lion analogy. Let's say that the black jacket wearing group lives and the white jacket group is consumed. We need try this experiment at different zoos and with different colored jackets. Don't exclude the possibilities of sending robots wearing black jackets to the Serengeti. Perhaps lions don't like dinner jackets but like black leather jackets. We keep testing to determine the range of validity of the theory.

Science is a dynamic process. No single experiment or single theory solves everything and his held inviolate. Through these two processes, we keep "checking our facts" and refining our knowledge of what is "true".


<font size=-1>[ This Message was edited by: Wiley on 2002-03-05 14:24 ]</font>

Roy Batty
2002-Mar-05, 10:01 PM
How about double blind testing. Dont tell the people/robots what theyre wearing & dont tell the experimenters till after the feast/not feast is over.
But should we tell the lions.. /phpBB/images/smiles/icon_wink.gif

DJ
2002-Mar-06, 02:29 PM
Thanks to all who responded to my very simple analogy. I realized as I went to bed last night a whole bunch of technical holes in it, which if exploited to the letter would ruin the overall message. However, I am pleased that many of you really did "get it."

Remember that quote on the bottom of the BA homepage... the one by Mark Twain? It's the same message.

We should all humbly acknowledge our lack of ability to examine things from any other viewpoint than the current viewpoint. Unfortunately, that viewpoint is from within, and being within something does not allow us the most accurate observations.

Can a cell truly understand the body? Can it even conjecture, at any level, the grand function of it all, by being an integral cog?

I really don't think so. And damn, I really look good today! /phpBB/images/smiles/icon_wink.gif

informant
2002-Mar-06, 05:25 PM
DJ wrote:

“We should all humbly acknowledge our lack of ability to examine things from any other viewpoint than the current viewpoint. Unfortunately, that viewpoint is from within, and being within something does not allow us the most accurate observations.”

I would like to comment – not criticize – DJ’s statement. You know, aside from all the empirical evidence that supports science as a means to acquire knowledge I find that science is not arrogant about itself.
OK, there are always some stubborn die-hard scientists who will not let go of their favorite theories, and might even lobby against alternative explanations.
But I still find that the overall attitude of science/scientists is one of accepting that they just might not be always right.
No offense intended to the religious people on the board, but I don’t think I can say the say the same about religion, or even philosophy. At least with philosophy it’s generally a very personal matter. But religion is something you do in groups, and religious groups often just won’t even want to hear anything about the possibility that they might not be right.
Another thing is that some religions – not all – feel compelled to convert everyone to their faith, “for their own good, whether they like it or not”. I just don’t like this sort of attitude, and I don’t think it exits in science. Scientists may push a lot for an idea to be accepted, they may resist ideas that go against theirs, but for me it still isn’t the same.
In short, I find that scientists – give or take a few human flaws – are generally more humble about science, than priests about religion. They don’t have that I-know-it-all-and-there’s-nothing-else-worth-knowing attitude.

DJ
2002-Mar-06, 07:35 PM
I would have to agree, however I find that science OFTEN presents a lot of things as fact when they still truly conjecture. And while we may understand, do our children when it is taught a certain way at school? Or do we create a box that later we have to think ourselves out of? (If we teach big bang vs. creationism, but it's really just inflationary, have we done a good job?)

I am not very religious -- way too messy, etc etc etc, but I do like metaphysics quite a bit. It's weird, that name: Metaphysics, physics, etc. Meta = A prefix meaning one level of description higher. (According to one of many descriptions on Dictionary.com).

I wonder who got that designation. I consider it a coup!

DJ

Wiley
2002-Mar-06, 08:15 PM
On 2002-03-06 14:35, DJ wrote:
I would have to agree, however I find that science OFTEN presents a lot of things as fact when they still truly conjecture. And while we may understand, do our children when it is taught a certain way at school? Or do we create a box that later we have to think ourselves out of? (If we teach big bang vs. creationism, but it's really just inflationary, have we done a good job?)

DJ


I disagree that science often presents things as facts when it really conjecture. I think its the popular media that presents conjectures as facts. If you read the actual technical papers, terms like "the evidence suggests" or "a possible explanation is" are common. While the author may write "The evidence suggest Twinkies cause weight gain" the popular media will shorten this to the more authoritive "Twinkies cause obesity".

As to what to teach in school, this leads to another question: When is a theory good enough? For instance Newton's theory of gravity, not Einstein's, is taught in schools. Einstein's theory of gravity is more accurate and qualitatively very different. So why do we teach gravity as a force as opposed to a curving of space-time. Simply because for 99.99999% of our everyday experience is explained accurately by Newton's theory. Newtonian mechanics is used to build houses, cars, nearly everything, while most people will only use general relativity for the GPS.

So the question remains, when is a theory good enough? Newton's theory is good for engineers but not for cosmologists. If we have a theory that explains all observations and makes all the right predictions, i.e., it perfectly explains nature from our limited perspective, can we call it reality? Newtionian mechanics is subsumed by general relativity, which eventually will be subsumed by a theory of quantum gravity. But suppose eventually we find a theory that explains our reality, is it true? Kind of an ontological definition of true.

ToSeek
2002-Mar-06, 10:19 PM
On 2002-03-06 15:15, Wiley wrote:

So the question remains, when is a theory good enough? Newton's theory is good for engineers but not for cosmologists. If we have a theory that explains all observations and makes all the right predictions, i.e., it perfectly explains nature from our limited perspective, can we call it reality?


I don't think you can ever have a theory that explains all observations, just one that explains all the observations you've made so far. So there's always the possibility of a better theory.

Wiley
2002-Mar-06, 11:41 PM
On 2002-03-06 17:19, ToSeek wrote:


On 2002-03-06 15:15, Wiley wrote:

So the question remains, when is a theory good enough? Newton's theory is good for engineers but not for cosmologists. If we have a theory that explains all observations and makes all the right predictions, i.e., it perfectly explains nature from our limited perspective, can we call it reality?


I don't think you can ever have a theory that explains all observations, just one that explains all the observations you've made so far. So there's always the possibility of a better theory.



I agree. And Godel's incompleteness theorem would preclude a true theory of everything, or at least an axiomatic theory of everything.

My question is more how do we differentiate theory from reality. Compare the special theory of relativity and Lorentz's theory. Both have the same quantitative predictions; they both give the Lorentz transformations. Qualitatively they could not be more different. Lorentz's theory is based on an absolute reference frame and an actual force performing the contraction, but like SR, it predicts a null result for MM and Fizeau experiments. So why do we choose Einstein over Lorentz? Is it purely aesthetic? Lorentz's theory also says we can never know our velocity with respect to the ether, so that we can never know an object's true length or an event's true duration. Most physicists find this idea unpalattable. Or is it because SR generalizes to incorporate gravity? But Poincare extended Lorentz's theory to the dynamic case in 1905 (I think its also the first paper to predict gravity waves, but I'm still researching that).

I suppose one has to remember that a theory is only a mathematical reprensentation of reality, not necessarily reality. Why do I feel like I am arguing DJ's case all of a sudden? /phpBB/images/smiles/icon_smile.gif

Azpod
2002-Mar-07, 12:12 AM
I suppose one has to remember that a theory is only a mathematical reprensentation of reality, not necessarily reality. Why do I feel like I am arguing DJ's case all of a sudden? /phpBB/images/smiles/icon_smile.gif


Because DJ is making an argument that has its roots in metaphysics: that there is a reality that everything we observe is merely a subset of. One cannot use science to describe this reality, because we cannot observe all of it. It's like being inside of a bubble whose barrier cannot be breached. One can describe everything inside the bubble to perfection, but one cannot describe anything outside of the bubble.

This is where Ockham's Razor is applied. One can dream up infinite realities that surround our observable one, but if these realities cannot be observed or tested in any way, they are useless when one is trying to create theories for the subset that can be observed. Likewise, theories that try to explain how these two realities interact can be safely discarded for simpler ones that only rely on the observable reality. This is because while both can explain all observed phenonemon, one can be tested and the other cannot.

I happen to believe that what we can observe and test is only a tiny part of a larger universe, but that is because of my faith as a Christian. However, I know that science cannot explain this meta-universe, nor can my faith explain why the ISS orbits the Earth. They are seperate things, and should remain that way.

Metaphysics is not science. It is an interesting philosophical and religious discipline, one that I have had many arguments about when I was in college. But simply because it is not testable, it does not meet the criteria of being scientific. It is people's attempts to treat metaphysics as if it was science that creates much of the pseudoscience that exists out there.

If you can construct an experiment to prove any metaphysical theory that can be repeated, and cannot be explained any other way, then I will happily consider your theory. But then again, at that point your theory would enter the realm of hard science, not metaphysics!

_________________
Lobster sticks to magnet. (http://www.solarisdx.net/features/1lm.html)
That is all.

--Azpod... Formerly known as James Justin

<font size=-1>[ This Message was edited by: Azpod on 2002-03-06 19:24 ]</font>

informant
2002-Mar-07, 08:17 AM
Commenting on DJ again... /phpBB/images/smiles/icon_smile.gif

About Big Bang vs. Creationism:
I don't object to both of them being taught in schools. I just think it shouldn't be in the same subject.
The Big Bang theory, to me, is science. It hasn't exactly been proven that it's right, but there is quite an amount of objective evidence to support it. So it should be taught in a science class.
Creationism - in the sense of the theory that the universe was created by a higher being - is not science. Not only is there no physical evidence to support it (if you discard religious texts), but it's hard to see what kind of evidence there could ever be to support it.
Creationism could be taught in some class of religion, but it shouldn't be presented as science. I think the most important is not as much to put science before religion, or vice-versa, but to put each of them in their rightful place.

informant
2002-Mar-07, 08:42 AM
About Wiley's question: when is a theory good enough?...

I think Newtonian physics is taught in high school instead of Relativity Theory mainly because:
-yes, it is sufficient in some contexts;
-it is mathematically *simpler* than Einstein's theory (I think; stop me on this any time if I'm wrong).
And it isn't exactly a "wrong" theory; it can always be looked at as an approximation to Einstein's relativity, under "earth-like" conditions;
-Furthermore, I think it can be beneficial to teach older theories that were later replaced by better ones. Sometimes it's a good thing to take students through the same path that science itslef went through. It makes their learning easier, and it shows them how science progresses.

Regarding the more metaphysical issues, the German philosopher Immanuel Kant defined two different concepts: the "phenomena", which is the physical reality that we can experience with our senses, and the "noumena", the actual "truth" that lies beneath the appearances.
The purpose of science can usually be looked at as to describe - not as much to understand or explain - the "phenomena".
But the "noumena" is beyond its reach, because it cannot be observed (more accurately, you can never be certain that what you observe has any relation to the underlying truth, the "noumena"). The underlying truth is the realm of religion, metaphysics and philosophy.
Of course, you can always take the *philosophical* standpoint that scientific theories are good enough to describe the underlying truth, as well as the observable world...

Yeah, I read weird stuff... /phpBB/images/smiles/icon_biggrin.gif

ToSeek
2002-Mar-07, 02:31 PM
On 2002-03-07 03:42, informant wrote:
About Wiley's question: when is a theory good enough?...

I think Newtonian physics is taught in high school instead of Relativity Theory mainly because:
-yes, it is sufficient in some contexts;
-it is mathematically *simpler* than Einstein's theory (I think; stop me on this any time if I'm wrong).
And it isn't exactly a "wrong" theory; it can always be looked at as an approximation to Einstein's relativity, under "earth-like" conditions;


It's worth noting that all the astronavigation done for Project Apollo and the deep space probes is Newtonian because that's good enough for their purposes.

Wiley
2002-Mar-07, 08:51 PM
On 2002-03-06 19:12, Azpod wrote:

This is where Ockham's Razor is applied. One can dream up infinite realities that surround our observable one, but if these realities cannot be observed or tested in any way, they are useless when one is trying to create theories for the subset that can be observed. Likewise, theories that try to explain how these two realities interact can be safely discarded for simpler ones that only rely on the observable reality. This is because while both can explain all observed phenonemon, one can be tested and the other cannot.



Ah yes, thank you, Ockham's Razor. That's the answer I'm looking for.

In the Lorentz's theory v. SR, do we choose some mystical force that causes things to contract when they move? or do we choose simple kinematics? Fundamentally SR is very simple. Of course, I say this with 100 years hindsight. To the turn of the century physicist choosing between the aether and coupled time and space, the "simpler" choice was not obvious.



<font size=-1>[ This Message was edited by: Wiley on 2002-03-07 15:55 ]</font>