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small axe
02-16-2009, 09:46 AM
Here's a simpleton question, but now it's troubling me!

If Space/Time is expanding outwards and apart (starting with the sub-atomic sized Universe expanding "outwards" at huge velocity) ...

If the model we always see is "dots drawn on the surface of an inflating balloon, the dots moving apart ...

If dark energy now seems to be pushing the universe outwards (and at accerlerating rates) AGAINST the gravitational attraction that would tend to pull galaxies back closer and collide ...

How can galaxies be moving closer to collide INTO each other?

Shouldn't everything be moving AWAY from everything else?

If everything starts at the same place, and has the energy to move APART at the BEGINNING ... what force can pull yhem back together again?

Even given gravitational attraction ... the galaxies should've been closer together a million years ago than they are today, right? If dark energy is making ANY space expand ... shouldn't ALL space be expanding (and thus, galaxies moving APART)?

Like I admit, it's a simpleton's question, so I hope it's a quick and effortless answer!

CACTUSWENDY
02-16-2009, 09:54 AM
Interesting question. I will look forward to what the reply is.

Romantic Heretic
02-16-2009, 06:50 PM
The 'moving apart' is an average. Overall the edges of the universe are moving away from the center and taking the galaxies with it.

However, within the confines of the universe there is a lot of random movement. Some galaxies are moving in directions other than straight away from the center.

So it is possible for galaxies to collide. Although I think 'intersect' would be better word.

stephenf
02-16-2009, 07:14 PM
Our Galaxy , the Milky Way, is not just expanding it is also spinning and moving through space. We are travelling at half a million Kilometres an hour, and it has been estimated that in two billion years from now , we will collide with another spiral Galaxy Andromeda.Taking a further three billion years to form into a new larger Galaxy.There is at the centre of our Galaxy a black hole three million times as massive as our sun.Andromeda has a black hole ten million times as massive. No one is sure what will happen when the two black holes meet.

Higgins
02-16-2009, 07:26 PM
Here's a simpleton question, but now it's troubling me!

If Space/Time is expanding outwards and apart (starting with the sub-atomic sized Universe expanding "outwards" at huge velocity) ...

If the model we always see is "dots drawn on the surface of an inflating balloon, the dots moving apart ...

If dark energy now seems to be pushing the universe outwards (and at accerlerating rates) AGAINST the gravitational attraction that would tend to pull galaxies back closer and collide ...

How can galaxies be moving closer to collide INTO each other?

Shouldn't everything be moving AWAY from everything else?

If everything starts at the same place, and has the energy to move APART at the BEGINNING ... what force can pull yhem back together again?

Even given gravitational attraction ... the galaxies should've been closer together a million years ago than they are today, right? If dark energy is making ANY space expand ... shouldn't ALL space be expanding (and thus, galaxies moving APART)?

Like I admit, it's a simpleton's question, so I hope it's a quick and effortless answer!

It's not a simple question, but the simple answer is that the force(s) that are causing the expansion are the same forces that cause collisions. For example, Andromeda is heading for our galaxy because in the local group of galaxies that's the gravitational (+dark energy?)situation. If you take the gravitational situation of the local group its getting pulled in a million other directions by a million other gravitational sources. Its the combined gravitational pull of a million sources pulling a million sources in all different directions that gives a gravitational metric that is part of the expansion. dark energy is contributing more (I guess-- or only 1/3 as much: see the notes)...but the multiple source metric/solution will work even in Newtonian physics with the right kind of "dust"(ie point sources) so I'm told.

Here's some notes about how the newtonian approximations lead into the standard metric.

http://www.astro.uu.se/~nisse/courses/kos2008/lnotes/ln3.pdf

Nivarion
02-16-2009, 07:47 PM
my guess is, that some galaxies are closer to the dark energy source that is pushing them, so they are accelrating more. they over take the ones that are further and therefore not moving as fast.

thats just me guess though.

Higgins
02-16-2009, 08:17 PM
Even given gravitational attraction ... the galaxies should've been closer together a million years ago than they are today, right? If dark energy is making ANY space expand ... shouldn't ALL space be expanding (and thus, galaxies moving APART)?

Like I admit, it's a simpleton's question, so I hope it's a quick and effortless answer!

Here's another way of looking at it: Dark energy (being as near as anyone can tell a feature of all vacua) is just an extra term in the gravitational metric. So if attractive situations in the field dominate then things move together (eg Andromeda toward the Milky Way) and if the field strength is very low (out in the middle of nowhere then you get "expanded vacuum"....

benbradley
02-16-2009, 10:04 PM
Here's a simpleton question, but now it's troubling me!

If Space/Time is expanding outwards and apart (starting with the sub-atomic sized Universe expanding "outwards" at huge velocity) ...

If the model we always see is "dots drawn on the surface of an inflating balloon, the dots moving apart ...
Yes, but the ballon thing is a very crude, first-order approximation. The dots are fixed in relation to the ballon's surface, so as the ballon is inflated, the dots will always move apart. In the real world, partices (or galaxies or whatever) are not connected by any such 'surface', and are free to move about in relation to one another.

The 'moving apart' is an average. Overall the edges of the universe are moving away from the center and taking the galaxies with it.

However, within the confines of the universe there is a lot of random movement. Some galaxies are moving in directions other than straight away from the center.
And even if all particles of matter started off moving directly away from the center (thus every particle would indeed be moving away from every other particle), they are randomly distributed, and some particles that are nearer to each other than to others will have more gravitational force towrd each other and start falling toward each other. More particles will coalesce due to their gravitational attraction, forming stars and galaxies and stuff. Two nearby galaxies, heading away from the origin of the Universe, will initially be heading away from each other but their mutual gravitational attraction can bring them toward each other.

Dark matter and dark energy add a confounding force to this (apparently these things were hypothesized because scientists were confounded that things weren't quite exactly acting as they 'should' with known 'visible' matter and energy), but they're not needed to explain the basic idea.

The "alternative" is for all particles to be evenly distributed throughout the Universe, and that would be awfully boring.

It's interesting that at the really small scale atoms and molecules bounce off each other, giving rise to gas pressure which tends to push them apart. If you pop a ballon in outer space the air or gas molecules will disperse. But at a much larger scale, trillions (or whatever the power of ten should be) of tons of gas will come together due to gravitational force to form a star.

Sophia
02-16-2009, 10:06 PM
If the model we always see is "dots drawn on the surface of an inflating balloon, the dots moving apart ...

If dark energy now seems to be pushing the universe outwards (and at accerlerating rates) AGAINST the gravitational attraction that would tend to pull galaxies back closer and collide ...

How can galaxies be moving closer to collide INTO each other?


It might not have been stated clearly when this balloon model was mentioned, but the dots represent clusters of galaxies, rather than individual galaxies. We, the Earth, our Solar System, the Milky Way or even our Local Group of galaxies aren't expanding - at these levels, everything is bound together by electrical and gravitational forces of attraction between the constituent atoms and molecules. It's only when you get to the scale of clusters of galaxies that expansion dominates what is happening. As individual galaxies fall below this scale, collisions between them are possible.

Angelinity
02-16-2009, 10:07 PM
Here's a simpleton question, but now it's troubling me!

If Space/Time is expanding outwards and apart (starting with the sub-atomic sized Universe expanding "outwards" at huge velocity) ...

If the model we always see is "dots drawn on the surface of an inflating balloon, the dots moving apart ...

If dark energy now seems to be pushing the universe outwards (and at accerlerating rates) AGAINST the gravitational attraction that would tend to pull galaxies back closer and collide ...

How can galaxies be moving closer to collide INTO each other?

Shouldn't everything be moving AWAY from everything else?

If everything starts at the same place, and has the energy to move APART at the BEGINNING ... what force can pull yhem back together again?

Even given gravitational attraction ... the galaxies should've been closer together a million years ago than they are today, right? If dark energy is making ANY space expand ... shouldn't ALL space be expanding (and thus, galaxies moving APART)?

Like I admit, it's a simpleton's question, so I hope it's a quick and effortless answer!

you're thinking in two dimensions. add a few--several, but at least two more.

Higgins
02-16-2009, 10:38 PM
Here's another way of looking at it: Dark energy (being as near as anyone can tell a feature of all vacua) is just an extra term in the gravitational metric. So if attractive situations in the field dominate then things move together (eg Andromeda toward the Milky Way) and if the field strength is very low (out in the middle of nowhere then you get "expanded vacuum"....

Same course notes...something on metrics:

http://www.astro.uu.se/~nisse/courses/kos2008/lnotes/ln2.pdf

Lhun
02-16-2009, 11:01 PM
my guess is, that some galaxies are closer to the dark energy source that is pushing them, so they are accelrating more. they over take the ones that are further and therefore not moving as fast.

thats just me guess though.
It's reasonable for a guess, but not what really happens.
"Everything moves away from everything else" is basically correct, just as the mentioned ballon model, only in 3D. There is no single source everything is pushed away from. The balloon model was first invented to show how expansion works when you have no center, and everything move away from everything else, not away from one common point.
Another feature of universe expansion is however that the farther apart two object are, the faster they move away from each other. And the reverse, obviously.
Very distant galaxy move away from each other at a speed faster than the speed of light, while galaxies close to each other can have individual dV that results in collisions.
Note: galaxies can only exist because of this, gravity is strong enough to hold galaxies together even though all the stars move away from each other. And all atoms in the stars from all other atoms etc.
One scenario is that in time, the (accelerating) expansion of the universe will have reached a speed at which not even atoms will stay coherent.

MelancholyMan
02-18-2009, 01:44 AM
Personally, I'm not convinced that space is expanding or that there is dark matter at all. This is not the first time that learned people have observed a phenonemnon and fabricated an explanation that turned out to be wrong. And they have a nasty habit of killing people who don't agree.

The only evidence for expansion is red-shift. No matter what direction you look, everything has a red-shift. And the farther away it is, the bigger the red shift. So, the farther away something is, the faster it appears to be moving away from us. The only explanation that fits is universal expansion. But isn't it possible that these red-shifts could be caused by something other than recessional velocity? We've only known about red-shifts in stars for a hundred years or so. And man thought the Earth was the center of the universe for several thousand years before he figured out it wasn't.

Don't look too closely at the 'science' behind estimates of the age or size of the universe, they have as many shaky assumptions as a Medieval alchemist. Beyond parallax, good for hundreds of light years, and Cepheid variables, good for a few million light years, there is NO universal yardstick. No doubt the universe is very old, and no doubt it is very large, but when science becomes intransigent to new ideas, as it is now, and towing a line to keep your career on track becomes necessary, it is no longer science but politics. And politicians NEVER get it right.

So, galaxies colliding is no big deal. We have pictures of it happening, after it has happened, and about to happen. Shelve expansion and dark matter and let your mind wander! Come up with your own explanations for the phenomenon we see, they are valid as any other.

As for dark matter, the idea of the ether has only been dead for about a hundred years(Michaelson Morley Experiment) and now it has apparently been resurrected! Amazing how science, which claims to be totally emperical, and often denounces those who believe in the spiritual, will simply invent whatever abstractions are necessary to prop up a popular theoretical framework. No one has ever seen dark matter. Never measured any. We know NOTHING about it. Yet it's existence has already gone past theoretical and become accepted. Faith? I guess scientists have it too.

kuwisdelu
02-18-2009, 06:02 AM
There are several factors that could be considered in an explanation, but the most important and and simplest one is this:


Here's another way of looking at it: Dark energy (being as near as anyone can tell a feature of all vacua) is just an extra term in the gravitational metric. So if attractive situations in the field dominate then things move together (eg Andromeda toward the Milky Way) and if the field strength is very low (out in the middle of nowhere then you get "expanded vacuum"....

While the universe is homogenous when taken on a large scale, this isn't true once you get really local. That is, while matter is--more or less--evenly distributed throughout the universe, you will still have areas where matter is more concentrated than others--galaxies, galaxy clusters, superclusters, etc. While the universe is expanding on the large scale, gravity can be the more powerful and dominant force in these local interactions.


Personally, I'm not convinced that space is expanding or that there is dark matter at all. This is not the first time that learned people have observed a phenonemnon and fabricated an explanation that turned out to be wrong. And they have a nasty habit of killing people who don't agree.

The only evidence for expansion is red-shift. No matter what direction you look, everything has a red-shift. And the farther away it is, the bigger the red shift. So, the farther away something is, the faster it appears to be moving away from us. The only explanation that fits is universal expansion. But isn't it possible that these red-shifts could be caused by something other than recessional velocity? We've only known about red-shifts in stars for a hundred years or so. And man thought the Earth was the center of the universe for several thousand years before he figured out it wasn't.

As you pointed out yourself, though, it's the only explanation we currently have. It fits the observations, and we can make models and predictions from it. It may not be perfect; it may be completely wrong, but that fact is that it's the best thing we've got. I understand your skepticism, but I don't really think "because it might be wrong" is a good enough reason to dismiss a very good explanation.

Until someone comes up with new, experimentally testable physics that would better explain the observations, most of us are going with an expanding universe.


So, galaxies colliding is no big deal. We have pictures of it happening, after it has happened, and about to happen. Shelve expansion and dark matter and let your mind wander! Come up with your own explanations for the phenomenon we see, they are valid as any other.

It's great to come up with one's own ideas. I've had a few of my own. But any idea would still have to have a lot of mathematical rigor, observational evidence to back it up to be anywhere near as valid.


As for dark matter, the idea of the ether has only been dead for about a hundred years(Michaelson Morley Experiment) and now it has apparently been resurrected! Amazing how science, which claims to be totally emperical, and often denounces those who believe in the spiritual, will simply invent whatever abstractions are necessary to prop up a popular theoretical framework. No one has ever seen dark matter. Never measured any. We know NOTHING about it. Yet it's existence has already gone past theoretical and become accepted. Faith? I guess scientists have it too.

I think you're getting a little carried away here. Dark matter isn't really like the "ether." Nor was it invented to prop up a merely "popular theoretical framework." General relativity is as good as we have right now for understanding gravity, and I'm guessing that would have to be the "popular theoretical framework" to which you refer. General relativity may not be perfect--hell, it certainly won't be close even, and neither will QM, until we can unite them--but it's extremely rigorous and has proven itself time and time again with observation and prediction.

Yes, "dark matter" was invented to explain the differences between GR's predictions and the observations in the velocities of outer stars in distant galaxies. The "missing matter" hypothesis was the best, unless there is a problem with general relativity--which there may well be. But with its track record, the more likely explanation is some kind of weakly interacting massive particles, or some other form of "dark matter," non-observable but through their gravitational effects. I'd hardly call it "faith" when one's belief is based on observational evidence and the scientific method.

While physics sure has had its share of embarrassments of scientists clinging to outdated ideas they believed just had to be correct, out of some faith or ego or intransigence (e.g., the ether, or even Einstein's rejection of QM), it's also had its share of discoveries through exactly these kinds of theoretical "inventions" and hypotheses. The positron, for instance, was theorized in a similar way--as a hypothesized particle naturally arising from a certain theoretical framework (the Dirac equation). No one knew whether it existed or not; no one had seen it before. Lo and behold, some testing later, and it existed.

No. We don't know what dark matter is. Does that really matter? We see its effects. We can measure them. When a better or clearer explanation comes along, we'll adopt that. But for now, they "dark," or unknown, and what appears to be "matter," and ultimately, that's just place-holder until we know what the heck it really is (or manage to explain it away through revision of GR).

Skepticism is good. But sometimes it's easy to get carried away and dismiss good ideas.

small axe
02-18-2009, 08:24 AM
But for now, they "dark," or unknown, and what appears to be "matter," and ultimately, that's just place-holder until we know what the heck it really is (or manage to explain it away through revision of GR).
Skepticism is good. But sometimes it's easy to get carried away and dismiss good ideas.

Well, obviously I'm the one asking the questions, so I'm not knowing the answers!

That said, some people would point out:

Others who have to "make up" mysterious dark energies and forms of matter (and seven extra dimensions of space/time) for which there is no evidence just to make their own materialist theories work out ...

Are indeed teetering dangerously (or at least unrationally) into the realms of mere "faith" :poke:

If we are happy imagining spooky extra dimensions ... who is to say those dimensions are not ALSO inhabitted by ghosts and gods, along with the supposed Theories Of Everything?

No one.

No one can say that ... except those who allow themselves their own "faith" when necessary to support their positions ...

Yet scorn the faiths of others.

Freeman Dyson in his interesting book "INFINITE IN ALL DIRECTIONS" makes the fascinating suggestion that "It is impossible to calculate in detail the long range future of the universe without including the effects of life and intelligence" ... and that it may be 'philosophically regretable' that the same question is not explored in regards to the EARLY history of the universe. :)

A universe that generates INTELLIGENT BEINGS might be fundamentally as greatly shaped by Intelligence as it is shaped by Gravity or "dark energy" etc.

Perhaps even more shaped by Intelligence than by Gravity. After all ... Gravity acts without plan or motive ... while Intelligence can empower itself and its effect a million-fold via planning and motive!

http://www.mactonnies.com/paranoia.jpg

And so we must ask ourselves, which is at play?

"dark energy" ? Or ...

"dark" MOTIVES ???

Higgins
02-18-2009, 07:34 PM
Well, obviously I'm the one asking the questions, so I'm not knowing the answers!

That said, some people would point out:

Others who have to "make up" mysterious dark energies and forms of matter (and seven extra dimensions of space/time) for which there is no evidence just to make their own materialist theories work out ...

It is not easy to take the universe as it is and try to figure out an explanation based on what we can directly verify experimentally. The thing about "materialist" theories is that they have a requirement that they be materially verifiable. Eg. microwaves on earth act like microwaves from the beginning of time. ie they are microwaves and have all kinds of materially verifiable characteristics.

Theories that have no material predictions or verifications are easy to articulate at one level, but they don't give you any indications about anything. So if you want to figure things out you are stuck with the difficulties of materialist theories.

veinglory
02-18-2009, 08:15 PM
As an analogy, shrapnel moving outwards from an explosion can still collide and bounce off other shrapnel. Exactly how things move from the central point depends on a lot of other factors.

kuwisdelu
02-18-2009, 10:16 PM
Well, obviously I'm the one asking the questions, so I'm not knowing the answers!

That said, some people would point out:

Others who have to "make up" mysterious dark energies and forms of matter (and seven extra dimensions of space/time) for which there is no evidence just to make their own materialist theories work out ...

Are indeed teetering dangerously (or at least unrationally) into the realms of mere "faith" :poke:

If we are happy imagining spooky extra dimensions ... who is to say those dimensions are not ALSO inhabitted by ghosts and gods, along with the supposed Theories Of Everything?

No one.

No one can say that ... except those who allow themselves their own "faith" when necessary to support their positions ...

Yet scorn the faiths of others.

I'm not scorning the faith of others, merely demonstrating that such explanations are more than simply "faith."

I'm pointing out that someone is more than just "faith" if it has experimental and observational support. The effect of dark matter has been observed. What it is, we do not know. If physicists were proclaim tomorrow "we know exactly what dark matter is!" without experimentally verifiable evidence, that would be an act of pure faith.

Say someone doesn't know about gravity. Call this person Bob. Bob sees an apple fall. He notices when he jumps up and down, he also falls. Bob takes it as an assumption that when he is not moving, he is standing still (not quite accurate, but let's run with it like that). Say Bob comes up with an idea, called the force of Plemton. Plemton made the apple fall! Plemton makes all objects fall!

Does this person know what Plemton is? Does he understand exactly how it works? Does he understand the mechanism of how it works? No. Is he acting out of pure "faith" that Plemton is real and exists--no, because he's seen its effects. In this analogy, Dark Matter is Plemton.

Just because we don't know what Dark Matter or Plemton are doesn't mean they don't exist. And if they don't exist, it may be that one of our fundamental postulates is wrong. In Bob's case, it might be that he is standing still--he could be standing on a platform accelerating upward at 9.8 m/s^2 instead. In our case, there may be a flaw with General Relativity.

But every suggests to Bob he really is standing still. Everything suggests to us General Relativity is a very good model.

It's not faith when it's based on evidence.


In the case of string theory and your extra dimensions--well, those extra dimensions come about as a necessary side-effect of string theory, which is has a rigorous mathematical framework. Now string theory has made no experimentally testable hypotheses yet--so I'd actually agree with you here that those that "believe" string theory to be necessarily correct are acting on pure faith. But I would disagree that coming up with ghosts and gods that inhabit those other dimensions are just as valid scientifically--and if you're not speaking scientifically, then that's just fine. But scientifically, string theory does predict the rest of current physics--you can work our electricity, magnetism, etc., from it. It works. So that does prove extra dimensions wouldn't contradict our current understanding of physics, and could even follow from a new understanding.

But come up with ghosts and gods all you like. No one's stopping you.

Take something like Dark Energy. I don't think there's much of a question it exists. We don't know what it is. If you want it say it's the hand of God, then I'll say that that's a perfectly valid explanation. But merely suggesting its existence--which is observable--is not on the same level of pure faith.

geardrops
02-19-2009, 12:16 AM
As you pointed out yourself, though, it's the only explanation we currently have. It fits the observations, and we can make models and predictions from it. It may not be perfect; it may be completely wrong, but that fact is that it's the best thing we've got. I understand your skepticism, but I don't really think "because it might be wrong" is a good enough reason to dismiss a very good explanation.

Until someone comes up with new, experimentally testable physics that would better explain the observations, most of us are going with an expanding universe.

This mentality is potentially damaging to the field of science. Yes, we should work off theories we have, but we should also always question those theories, lest we find ourselves trapped in a paradigm-driven body of science.

Yes, I like Kuhn.

MelancholyMan
02-19-2009, 12:20 AM
I don't necessarily accept that the effects of dark matter have been observed. We have observations, yes, but we can't be sure the interpretation is correct for the reasons I pointed out previously. I am not the only scientist in the world who suspects that something other than recessional velocity is the only thing responsible for red shift. And every measurement that supports the existence of dark matter is based on velocity dependent red shift analysis. Gravity, for instance - as predicted by SR - will induce a red shift on light departing the gravitational field.

At the same time, it is possible that Dark Matter exists. It is also possible that extraterrestrials exist. But just because something is a possibility, doesn't mean it should be thought of as true. The same argument applies to evolution. Whether you believe it or not, it is by no means an open and shut argument as many would have you believe. All the hominid bones ever found would not fill even a single coffin.

Being a scientist myself I'm not against theoretical frameworks being erected in an attempt to explain things. Unfortunately, the first generation talks about it as a hypothesis, the second talks about it as a theory, and the third talks about as a fact - as has happened with evolution, when virtually nothing has been proven. In almost every case, it becomes a political argument resistant to new ideas. That's the only thing I'm against.

Personally, if the observations are correct, I tend to think that dark matter isn't exotic at all - as was the immediate conclusion - but something much more mundane like, say, brown dwarfs. There are estimates that up to half a galaxy's mass might be in the form of brown dwarfs; gaseous bodies that lack the mass to initiate fusion and so are dark. Entire solar systems surrounding brown dwarfs could outnumber stars by more than ten times and still be spread out enough to go completely unnoticed.

And as a note, Einstein didn't reject QM. Einstein rejected one of the interpretations of QM. He understood that it worked well in predicting interactions, he just didn't accept that the randomness was an actual effect but felt it was only a convenient abstraction to explain the observed behavior... sort of like dark matter. :-)

Lhun
02-19-2009, 01:16 AM
This mentality is potentially damaging to the field of science. Yes, we should work off theories we have, but we should also always question those theories, lest we find ourselves trapped in a paradigm-driven body of science.

Yes, I like Kuhn.
The problem with Kuhn is that he was wrong about one small, yet important detail. The way science progresses, differently than Kuhn theorizes, is that a better theory comes along. The thing is, we need to have theories of the physical world to do mundane activities like designing computers and airplanes. If someone comes along and succesfully questions a theory, proving that it's wrong, he still can't expect anyone to stop using that theory. It'll still be in use until someone finds one that works better than the old one.
Too many people get high on the "questioning established dogma" part and forget that the "finding better explanation" part is what's really important.


Well, obviously I'm the one asking the questions, so I'm not knowing the answers!

That said, some people would point out:

Others who have to "make up" mysterious dark energies and forms of matter (and seven extra dimensions of space/time) for which there is no evidence just to make their own materialist theories work out ...

Are indeed teetering dangerously (or at least unrationally) into the realms of mere "faith" :poke:
What you have to keep in sight here is that physicists didn't came with dark matter and energy while smoking a lot of pot one evening and thinking "hey, cool idea, we don't know better so let's run with this".
Science follows Occams Razor, i.e. dark matter and dark energy are the simplest explanations we have currently available. Supernatural theories are neither simple nor useful, science can only deal with natural explanations.

Lhun
02-19-2009, 01:24 AM
<snip>Out of curiousity, if you don't mind me asking, what is your scientific field/area of expertise?

geardrops
02-19-2009, 01:31 AM
Too many people get high on the "questioning established dogma" part and forget that the "finding better explanation" part is what's really important.

I think this really comes down to personal philosophy. The pragmatist will want a better functioning theory, and the ... theorist? I can't think of a better term ... will be interested in the holes poked in the theory.

The problem is the pragmatists tend to "win" to the point where instead of talking of things as a best-fit theory we talk about it as a real thing. So we get things like "dephlogistated air."

ETA: I also think this confuses science with engineering.

small axe
02-19-2009, 03:40 AM
I'm not scorning the faith of others, merely demonstrating that such explanations are more than simply "faith."

I didn't mean to suggest that YOU were scorning the faith of others! (I meant my use of 'others' to mean 'others' than those involved in our thread, etc)


But come up with ghosts and gods all you like. No one's stopping you.

Take something like Dark Energy. I don't think there's much of a question it exists. We don't know what it is. If you want it say it's the hand of God, then I'll say that that's a perfectly valid explanation. But merely suggesting its existence--which is observable--is not on the same level of pure faith.

I just worry that not knowing what something IS, but then saying it is 'observable' ... doesn't satisfy those (and I may not be one of those) who reply: How can you know WHAT you're observing UNLESS you know what it is?

I think I understand that YOU are using "dark" to mean that you're putting no claims upon its ultimate nature. (And that is good Science. That keeps the mind open to extreme possibilities that can rightfully be explored)

But ... I bet I could walk onto any University campus and find hundreds of educated adults, materialists who, not having ANY IDEA what 'dark energy' is ... and having NO BASIS for ruling out anything ... would demand that it CANNOT be "the Hand of God"

That, imo, is "faith"

In fact, it is NOT faith EQUAL TO the faith of God-worshippers, it is a far greater and less open-minded dogma!

Why?

Because I could find you a hundred Believers who could do the same exact and valid SCIENCE concerning "dark energy" ... and simply attribute it to GOD working through the natural laws of God's Creation. :)

The Believer can be open-minded and both Believe and still do quality Science.

The strict materialist (an extreme being the Athiest who demands that no God can exist) must on the other hand close his or her mind to a Universe of possible (but non-atheist) possibilities.

Why?

Because they demand that such a thing as the "supernatural" cannot exist -- based not upon Knowledge and Evidence, but upon Ignorance (what they DON'T know) and dogma.

I won't go so far as to suggest that Einstein's temporal relativity is the same thing as losing Time while in Fairyland and returning after a day in Faerie to realize centuries have passed here on Earth!

Just that what was once "supernatural" is now natural science; and what is today "supernatural" to the closed-minded can easily be the accepted Physics and Science of a more-enlightened Future.

Like I said: I didn't even know why galaxies can both expand away from each other and still collide (until it was explained! Thanks to all)

But there are some leaps into materialist dogma I still shan't make ... :)

small axe
02-19-2009, 04:01 AM
Science follows Occams Razor, i.e. dark matter and dark energy are the simplest explanations we have currently available. Supernatural theories are neither simple nor useful, science can only deal with natural explanations.

Occam's Razor has always troubled me, though: to ASSUME that the 'simplest' explanation is always the best one?

I realize that Science is in pursuit of the Theory of Everything, and sees ultimate knowledge in the UNIFICATION of currently diverse cosmic forces etc. The 'simplification' of the Universe.

But it seems that the POINT of the Universe is (and I'm just observing) towards COMPLEXITY. Increasing Diversity and Difference.

Stupid hydrogen atoms evolve into self-aware creatures who are trouble by Occam's Razor issues etc. The value of the human (to me) is to hear what the human Thinks and Dreams ... and not so much in the original state of the unborn fetus' DNA (which, again, is found in complexity, not simplicity)

A Unified Cosmos was ... well ... so basic that we cannot even grasp of what it was.

Play the movie back a few frames before the Big Bang and ... there isn't even a movie there to play, anymore.

The Meaning of the Movie isn't to be found in how it starts but how it ends, some suggest.

The Art of the movie isn't in the analysis of the chemicals upon the celluloid.

*shrug*

I blather.

Is there ANY example of Occam's Razor being WRONG? Where the simplest explanation ISN'T the true explanation?

I'm betting that where simplicity is,
Intelligence and Self-awareness haven't had much involvement. YET.

A Universe without those ... is an unfinished story, imo. :Sun:

Edited to Add:

I'm betting that where simplicity is,
Intelligence and Self-awareness haven't had much involvement. YET.

Unless we're taking some sort of Diety creationist approach, in which case "simplicity" can be seen as existential "elegance" and creating the Self (the highest form of Being) out of the most simple and lowest elements is part of the entire point. :)

The Joy there is that Complexity would not be impressed by understand Itself, but having Simplicity become Complexity would be COOLEST.

MelancholyMan
02-19-2009, 06:24 AM
Out of curiousity, if you don't mind me asking, what is your scientific field/area of expertise?

Not at all. Physics with specializations in astrodynamics, control theory, aerospace engineering, and atmospheric science. I currently work as a rocket scientist but we're a dime a dozen in this town.

And you?


What you have to keep in sight here is that physicists didn't came with dark matter and energy while smoking a lot of pot one evening and thinking "hey, cool idea, we don't know better so let's run with this"..

Actually, this is exactly how a lot of stuff gets started. Carl Sagan comes readily to mind. That dude admitted to smoking a lot of weed and dropping acid as well, and said that it opened his mind to new ideas. Tons of hippies were studying at physics departments during the seventies and wound up being my instructors, and a fair number of them still burned a dube from time to time.


Science follows Occams Razor, i.e. dark matter and dark energy are the simplest explanations we have currently available. Supernatural theories are neither simple nor useful, science can only deal with natural explanations.

I agree, but an exotic form of matter never before seen and completely untestable is NOT Occams Razor. Brown dwarfs and proto-planets are much simpler and far more likely, but carry the stigma of not being sufficiently exciting to garner additional funding from the NSF - the real basis of most theories anyway. Like everything else, and sadly so, money.

geardrops
02-19-2009, 08:55 AM
I'd really love to contribute to this thread, but MelancholyMan and small axe seem to prettymuch have my opinion covered, and with greater credentials than my BS/MS-in-progress in engineering.

Lhun
02-19-2009, 05:14 PM
ETA: I also think this confuses science with engineering.Not really, engineers aren't the only people who use scientific theories. Though their work is the most ovious confirmation of such theories.
I.e. all of astronomy needs solid physics to work, and any theory of physics that gets disproven will still be used as an assumption when doing astronomy until there is something better available.
Another thing to keep in mind when talking about scientific theories is the congruency principle. Any observation that gets explained by theory, must also be explained by other theories for them to be viable alternatives.
In other words, we can observe that apples fall down. Our theory of gravity explains why. We know that our theory of gravity is most likely very wrong (because we don't really understand much about gravity yet) but any theory someone comes up with that says apples don't fall down or cannot explain why apples fall down is wrong be default. Evidence trumps theory, always has and always will.

Lhun
02-19-2009, 05:26 PM
Occam's Razor has always troubled me, though: to ASSUME that the 'simplest' explanation is always the best one?
"Do not multiply explanatory entities beyond necessity" is the proper form for Occams Razor. I know i just say "simple" too, because it's shorter, but it's important to understand what is meant by "simple" in this context.

But it seems that the POINT of the Universe is (and I'm just observing) towards COMPLEXITY. Increasing Diversity and Difference.You cannot infer teleology from ontology. That's a basic logical error.

Is there ANY example of Occam's Razor being WRONG? Where the simplest explanation ISN'T the true explanation?
None that i know of. Which is not surprising, because by definition Occams razor refers to the most simple adequate explanation.

Unless we're taking some sort of Diety creationist approach, in which case "simplicity" can be seen as existential "elegance" and creating the Self (the highest form of Being) out of the most simple and lowest elements is part of the entire point. :)Having some kind of supernatural agent create the universe as in creationist phantasies is not simpler than the big bang model. It only sounds simpler. In explanatory terms it is much more complex, because you then have to find explanations for the existence of this supernatural agent. (and "he just does, he's god" doesn't cut it)
Imagine the old model of the earth, disc on elephants and all that.
When asked what the earth rests on, the answer "a turtle" is not simpler than a complicated answer explaining with lots of impressive mathematical and physical formulae how the earth floats in vacuum not needing anything to rest on.
"A turtle" might be easier to understand, but it is not simpler in terms of Occams Razor, because you just added another step to the process, resulting in the question what the turtle rests on. While the complicated explanation detailing how the disc floats on its own might be more difficult to understand but is simpler in terms of occams razor because it gives an answer to a question without creating another question just one step down.

Lhun
02-19-2009, 05:35 PM
Not at all. Physics with specializations in astrodynamics, control theory, aerospace engineering, and atmospheric science. I currently work as a rocket scientist but we're a dime a dozen in this town.So you're the guy i can PM to get competent opinions on missile design for SF? Or would that be classified? :D

And you?A few years of Chemistry at University, though i switched to philosophy before getting Masters degree. (~equivalent. Not an american uni)
I figured i wasn't interested enough in money to get through to a PHD in even a halfway interesting field, so i switched to something i'd gladly do all day for free.

Actually, this is exactly how a lot of stuff gets started. Carl Sagan comes readily to mind. That dude admitted to smoking a lot of weed and dropping acid as well, and said that it opened his mind to new ideas. Tons of hippies were studying at physics departments during the seventies and wound up being my instructors, and a fair number of them still burned a dube from time to time.Well ok, but usually the non-hippies call them on the BS if the only support for the theories is dop not data.

I agree, but an exotic form of matter never before seen and completely untestable is NOT Occams Razor. Brown dwarfs and proto-planets are much simpler and far more likely, but carry the stigma of not being sufficiently exciting to garner additional funding from the NSF - the real basis of most theories anyway. Like everything else, and sadly so, money.
As far as i'm aware brown dwarfs and proto-planets aren't being totally ruled out. Maybe i only read from sensible physicists about dark matter by accident.
Anyway, if wat you're critizing isn't dark matter as such, but positing exotic and exiting stuff in the absence of data, you won't hear disagreement from me. ;)

MelancholyMan
02-19-2009, 06:44 PM
So you're the guy i can PM to get competent opinions on missile design for SF? Or would that be classified? :D

censored


A few years of Chemistry at University, though i switched to philosophy before getting Masters degree. (~equivalent. Not an american uni) I figured i wasn't interested enough in money to get through to a PHD in even a halfway interesting field, so i switched to something i'd gladly do all day for free.

Perhaps the biggest misconception about science and engineering is that we make a lot of money. Even the Ph.D.'s. If you want to make money in science you have to either be an M.D. or start a company which requires, not knowledge of science and engineering, but business and politics - two of the things scientists and engineers generally hate the most. Of course, if I'd known the work was this dull I'd have majored in history, so I am with you on this one 100%.


Well ok, but usually the non-hippies call them on the BS if the only support for the theories is dope not data.

Sadly it has become so bureaucratic that as long as money is flowing, no one calls anyone on much of anything anymore. It is when the money stops flowing that things get interesting. The current economic downturn could distrupt the status quo and shake things up a bit.

And Dempsey, don't EVER think that because you think you don't have credentials that you can't add to a discussion. It is the very credentials we earn that blind us to the possibilities. That's why I don't generally discuss qualifications because it tends to color perceptions and bias the discussion. As the Bible teaches, "Let no man despise thy youth."

Always question.

Always probe.

Learn from those who offer to teach

Never assume the fashionable is correct when looking for an answer.

And KISS - Keep It Simple Stupid.

P.S. I saw two galaxies collide this morning. A pristine convertible '67 and a pieced out '65 hardtop. Sorry, but felt I had to stay on thread.:D

Lhun
02-19-2009, 07:20 PM
Perhaps the biggest misconception about science and engineering is that we make a lot of money. Even the Ph.D.'s. If you want to make money in science you have to either be an M.D. or start a company which requires, not knowledge of science and engineering, but business and politics - two of the things scientists and engineers generally hate the most. Of course, if I'd known the work was this dull I'd have majored in history, so I am with you on this one 100%.
Well "a lot of money" depends on what you consider a lot of course. For "a lot" me and my brother should have gone into IT and economics and spend the next thirty years working 12 hours a day to built up our father's company into something that sells for millions. We both opted out, and since we already declined the head start we'd get on the corporate game by inheriting a small but running company trying to start one in a different field doesn't seem so attractive.
But still, working as an employee in a company with a technical degree still guarantees you a starting wage of around 100k a year. At least here were i live.
While a degree in a social field (or philosophy) entitles you to a warm handshake from your boss at the cab company. :D

Sadly it has become so bureaucratic that as long as money is flowing, no one calls anyone on much of anything anymore. It is when the money stops flowing that things get interesting. The current economic downturn could distrupt the status quo and shake things up a bit.One can always hope, but i suspect that the pure sciences will only suffer. After all, there's no money to made from dark matter theories, be they wrong or right.

And Dempsey, don't EVER think that because you think you don't have credentials that you can't add to a discussion. It is the very credentials we earn that blind us to the possibilities. That's why I don't generally discuss qualifications because it tends to color perceptions and bias the discussion.I second this. On their own credentials don't mean zip. Arguing about stuff is the only way to find out who's right or wrong. (or, unfortunately, who's right but just sucks at explaining why)

kuwisdelu
02-19-2009, 07:27 PM
It seems to me we're arguing semantics more than anything, since I'm pretty much in agreement.

Essentially, I'm saying this:


As far as i'm aware brown dwarfs and proto-planets aren't being totally ruled out. Maybe i only read from sensible physicists about dark matter by accident.

Anyway, if wat you're critizing isn't dark matter as such, but positing exotic and exiting stuff in the absence of data, you won't hear disagreement from me. ;)

To me, "dark matter" encompasses the possibility of brown dwarfs and non-exotic matter. It's a place-holder term.

And of course, there's just the possibility that GR is more flawed than we think.

Higgins
02-19-2009, 07:30 PM
At the same time, it is possible that Dark Matter exists. It is also possible that extraterrestrials exist. But just because something is a possibility, doesn't mean it should be thought of as true. The same argument applies to evolution. Whether you believe it or not, it is by no means an open and shut argument as many would have you believe. All the hominid bones ever found would not fill even a single coffin.

The current cosmologically Big problem is dark energy not dark matter and here's more than one coffin load of homo erectus from one site:

http://www.uiowa.edu/~bioanth/ZhoukoudianModel.pdf

geardrops
02-20-2009, 03:28 AM
Another thing to keep in mind when talking about scientific theories is the congruency principle. Any observation that gets explained by theory, must also be explained by other theories for them to be viable alternatives.
In other words, we can observe that apples fall down. Our theory of gravity explains why. We know that our theory of gravity is most likely very wrong (because we don't really understand much about gravity yet) but any theory someone comes up with that says apples don't fall down or cannot explain why apples fall down is wrong be default. Evidence trumps theory, always has and always will.

My issue here lies in the treatment of filler-theories such as "dark matter" (or, seriously my favorite term because the word is so amazing, phlogiston) as fact.

(Seriously. Phlogiston. What an awesomely-shaped word.)

Yes, we can observe the apple falling. We call the "why" of apple-falling "gravity." Before gravity rolled onto the scene, we said that all matter likes to be at rest, on the ground, and that any matter, when displaced, will want to return to its natural place (thanks, Aristotle!).

But then when observing the planets, and observing things on earth, we started to see, hey, there's two sets of rules. Pieces stopped fitting together so well. Eventually we came to Newtonian physics, but this took many men many years of saying "Guys, something's not right here" for us to change.

Happened again with the ability to observe sub-atomic particles. The same laws that govern large bodies do not work on the small. Gravity is weird here. Et cetera.

So, fine, we have instances where incorrect models were replaced with more-correct ones when they became useful. But there's two problems here: one, the concern with usefulness as opposed to truth (which I'll grant is primarily a bit of idealism on my part but damnit I like science to be concerned with truth above all things); and two, the persistent use of incorrect or insufficiently proven models as truth, as opposed to recognizing them as temporary tools to get things done.

Understand this doesn't bother me on a practical level. I realize things like dark matter are useful in getting work done. But the problem arises when we stop talking about dark matter as a theoretical model and start talking about it like fact. The problem, to me, arises when lay people think dark matter is real, and envision little black balls of stuff bumping around in the outer reaches of space.

As was stated earlier, it's like what happened with evolution. It's a theory. A theory. If it was hard-proven we'd call it a postulate. Yes, a lot of data supports it. But a lot of data supported black holes and we still had to discover those.

I suppose this comes down to my issues with induction. Thank you, Hume, for ruining my life :)



And Dempsey, don't EVER think that because you think you don't have credentials that you can't add to a discussion. It is the very credentials we earn that blind us to the possibilities. That's why I don't generally discuss qualifications because it tends to color perceptions and bias the discussion. As the Bible teaches, "Let no man despise thy youth."

Well I was more saying that you all had my opinion covered, that anything I added would simply be restating what you said or quoting it with "QFT" slapped underneath. I don't think my seeming lack of credentials preclude me from any argument. Though I do try to step lightly and keep them under consideration.

And let me add to the list my minor in philosophy, which I considered furthering my education in. I chose engineering in the end, but I still read philosophy for fun :)

Dommo
02-20-2009, 05:47 AM
I agree on the credentials thing. It's largely why I dislike the way "Big Science" and the like are being done, because I think it often leads to group think types of situations, and leads to less than great results.

It's like with Nuclear Fusion. I think ITER isn't going to be the first to succeed in what they're doing, simply because too many people have their reputations at stake and will do whatever they can to protect themselves, even if it means stifling innovation. It's all the bureaucratic bullshit that's really hampering science and engineering.

small axe
02-20-2009, 08:09 AM
Originally Posted by small axe http://www.absolutewrite.com/forums/images/buttons/viewpost.gif (http://www.absolutewrite.com/forums/showthread.php?p=3304383#post3304383)
Occam's Razor has always troubled me, though: to ASSUME that the 'simplest' explanation is always the best one?
"Do not multiply explanatory entities beyond necessity" is the proper form for Occams Razor. I know i just say "simple" too, because it's shorter, but it's important to understand what is meant by "simple" in this context.

Quote:
But it seems that the POINT of the Universe is (and I'm just observing) towards COMPLEXITY. Increasing Diversity and Difference.
You cannot infer teleology from ontology. That's a basic logical error.

Oh. Okay.

Logic? Or mere observation?

But (changing my horse mid-stream etc because you has drownt the prettypony of my actual comment) the arrow of the Universe "POINTS" IN THE DIRECTION OF increasing Diversity and Difference. :)

Right?

I mean, isn't it fair to "observe" that things are getting more diverse and different, as Time progresses?

And observation then has naught to do with logic, perhaps. Observation is observation!

I'll have you know that "My observation skillz are intact! Only my conclusions are insane, sirruh!" :D

Unless, of course, they are supported by accurate observation.



Teleology (Greek (http://en.wikipedia.org/wiki/Greek_(language)): telos: end, purpose) is the philosophical (http://en.wikipedia.org/wiki/Philosophy) study of design and purpose (http://en.wikipedia.org/wiki/Purpose). A teleological school of thought is one that holds all things to be designed for or directed toward a final result, that there is an inherent purpose or final cause for all that exists.
http://en.wikipedia.org/wiki/Teleology

If the Meaningfulness of All Existence demands teleology, then it is a coin I'll pay to have Meaning, yes ...

As I mentioned above, many hold that Life and Awareness may ultimately shape the Universe to a greater extent than any of Science's blind "natural laws" acting blindly and randomly.

Logic. ha.
Life lives, and Logic scolds.

'Coincidence is God's way of remaining Anonymous' etc! :)

Higgins
02-20-2009, 06:35 PM
Understand this doesn't bother me on a practical level. I realize things like dark matter are useful in getting work done. But the problem arises when we stop talking about dark matter as a theoretical model and start talking about it like fact. The problem, to me, arises when lay people think dark matter is real, and envision little black balls of stuff bumping around in the outer reaches of space.

As was stated earlier, it's like what happened with evolution. It's a theory. A theory. If it was hard-proven we'd call it a postulate. Yes, a lot of data supports it. But a lot of data supported black holes and we still had to discover those.



:)

Evolution is a "theory" in the sense that it is an area of reseach like "gravitational theory". If I say "I'm working on evolution" I might mean I'm thinking about having sex, if I say "I'm working on evolutionary theory" I would mean I'm working in that area of reseach.

Dark matter is real in the sense that some effects are put under that heading.

Dark energy is real in the same way...they are essentially observations in search of a comprehensive theoretical frame work...which does exist for evolution which in turn means that evolution is currently much better understood than dark matter or dark energy.

kuwisdelu
02-20-2009, 09:49 PM
Dark matter is real in the sense that some effects are put under that heading.

Dark energy is real in the same way...they are essentially observations in search of a comprehensive theoretical frame work...which does exist for evolution which in turn means that evolution is currently much better understood than dark matter or dark energy.

Exactly what I've been trying to say.

I'm more of a scientist of an engineer, myself, too, in that I'm far more interested in "truth" than what "works."

The important part to remember is that the closer you get having a theory that "works" (better and better) usually the closer you're getting to the truth. Sometimes this is subverted (see Ptolemy and his epicycles), but more often than not, it's the case.

In the absence of truth, I think a working hypothesis that can be changed and improved is better than none at all. I do agree there is a problem when everyone accepts that hypothesis as "truth," and can be a barrier to true scientific work. At the same time, it's also important to remember talking about and researching that hypothesis is not the same as taking it as truth.

Higgins
02-20-2009, 10:31 PM
Exactly what I've been trying to say.

I'm more of a scientist of an engineer, myself, too, in that I'm far more interested in "truth" than what "works."

The important part to remember is that the closer you get having a theory that "works" (better and better) usually the closer you're getting to the truth. Sometimes this is subverted (see Ptolemy and his epicycles), but more often than not, it's the case.

In the absence of truth, I think a working hypothesis that can be changed and improved is better than none at all. I do agree there is a problem when everyone accepts that hypothesis as "truth," and can be a barrier to true scientific work. At the same time, it's also important to remember talking about and researching that hypothesis is not the same as taking it as truth.

On Kuhn's behalf it is worth noting that transitional theories can very very strange....melodramatic even...for example Kepler halfway between copernicus and Newton, halfway to unified gravity...but he gets the planetary orbits right:

~ Although Copernicus himslef never hoped that his predictions would be better than within 10', Kepler felt that Copernicanism was true period, and not merely a good approximation to the truth. If it is true, it should give exactly the right answers. This 8' of difference between prediction and observation in Mars's apparent position leads Kepler to reject a fundamental claim of astronomy that had been accepted for at least 2000 years: Kepler suggested that the planets' orbits were not exactly circular.


from http://faculty.unlv.edu/frostarn/MMSlecture8.htm

small axe
02-21-2009, 04:57 AM
Truth precedes proof. :D

Romantic Heretic
02-21-2009, 05:46 PM
I prefer wisdom to truth, myself.

TMA-1
02-21-2009, 06:10 PM
It is always discouraging to hear the old and flawed argument that "evolution is just a theory, not a fact". Actually theories and facts are different things, it's not like facts are promoted theories or something. A theory describes and explains observed facts. We know that life has evolved and continues to evolve, it is known that populations change in their genetic characteristics over time. There is really no doubt about it. The theories try to explain how it is happening, what the causes are. Theories are interpretations of facts.

Lhun
02-22-2009, 02:18 AM
It's like with Nuclear Fusion. I think ITER isn't going to be the first to succeed in what they're doing, simply because too many people have their reputations at stake and will do whatever they can to protect themselves, even if it means stifling innovation. It's all the bureaucratic bullshit that's really hampering science and engineering.I disagree here. While ITER seems like a worse choice than polywell now, it nonetheless is a very promising project. The big problem wit fusion research is that it got a bad reputation because it's often claimed that scientists said "it's 50 years from being ready" for 60 years or so.
While what you really should look at is that scientists say (and said) "it's x years and y million bucks from being ready" and since they never get y, the x won't shrink. The reasearch funds going into fusion worldwide are totally ridiculous when compared to other government spending, and that still today when global energy crisis is no longer an end-of-century scare.

small axe
02-22-2009, 07:59 AM
It is always discouraging to hear the old and flawed argument that "evolution is just a theory, not a fact". Actually theories and facts are different things, it's not like facts are promoted theories or something.

But how is it a 'flawed' argument ... when even you agree it is a true argument?

'Evolution is just a theory, not a fact' indeed.

Theories can and do change, as interpretations change.
Facts do not change.

Should schools educate our children with FACT, or mere theory? (Because Science and human history may be full of WRONG 'theories' ... and we don't pay to have our children taught on the validity of invalid Theories, as if Theory itself has lasting value.

A THEORY is only of value if it approaches (to the best of our understanding) FACT. Or as an example to how Theory can fall so far short of understanding Fact.

Much legal and cultural debate has occurred over people's wanting to make the DISTINCTION between Evolution Theory and Evolution "fact" a clear distinction. Science itself needs clear distinctions.

So 'evolution is just a theory, not a fact' isn't a flawed argument, but an attempt at a valid and clear distinction.

One distinction that needs to be made clear (not in our minds, but in the minds of young schoolchildren being graded on the "knowledge" they are taught as fact and then must regurgitate on school tests):
The 'evolution' of fruit flies is more scientifically supported than the supposed 'evolution' of humans from single-celled lifeforms. :)

The 'flaw' would be to teach them that both instances of supposed 'evolution' have equal scientific evidence or support.




A theory describes and explains observed facts. We know that life has evolved and continues to evolve, it is known that populations change in their genetic characteristics over time. There is really no doubt about it.

Of course there is doubt about it. Your statement is over-reaching in its over-generalization.

SOME life 'has evolved and continues to evolve.'
I suggest that you cannot demonstrate that ALL life 'has evolved and continues to evolve.'

Therefore, there can indeed be 'doubt' :Hug2:
When doubt is removed ... I suggest Science is crippled and withers.


The theories try to explain how it is happening, what the causes are. Theories are interpretations of facts.

Interpretations change.
Evidence changes.
FACTS are the reality, not our possibly flawed 'interpretation' or 'theory'

***

ETA: I don't say that to start some futile circular debate about "Evolution vs Creationism" -- both which can easily be twisted into strawman arguments etc -- (So let's not have one of those in a Science Fact thread!)

Statements (such as claims about Evolution) that are meant to represent Science and Scientific clarity, rationality, and factuality ... are open to analysis and critique, totally separate from any "religious" debate or dispute. imo

JS Emuakpor
02-22-2009, 04:52 PM
I would like to contribute, but I am a biologist - ask me about reproductive hormones and I may have something.


In fact, it is NOT faith EQUAL TO the faith of God-worshippers, it is a far greater and less open-minded dogma!

[...]

The strict materialist (an extreme being the Athiest who demands that no God can exist) must on the other hand close his or her mind to a Universe of possible (but non-atheist) possibilities.

I do want to say that I agree wholeheartedly with this. Then again, I have a strong spiritual faith and anything that cannot be fully explained by science, I accept as the Hand of God.

That being said, I also believe the theory of Evolution and the Creation Story are one and the same; so feel free to think I'm a lunatic!:Shrug:

Mac H.
02-22-2009, 06:14 PM
SOME life 'has evolved and continues to evolve.'
I suggest that you cannot demonstrate that ALL life 'has evolved and continues to evolve.'Indeed.

However, that applies to everything. We observe that lead is denser than hydrogen. It makes sense and is logical and is consistent that all lead is denser than hydrogen .. but we haven't examined every lead atom in the universe.

Should we then refuse to teach the density of lead as a 'fact' ?

Another example:
Kangaroos, Platypuses and Echidnas are native Australian animals. That is a 'fact', by any reasonable definition of the word.

However, should books on animals only report this as a 'mere theory' ?

After all, some people believe that Kangaroos, Platypuses and Echidnas once came out of a wooden box in Turkey, and then travelled to Australia. So by that belief they are not native to Australia.

Should that theory be taught, or would you be happy with textbooks referring to 'Kangaroos are native to Australia' being reported as a fact ?

You asked 'Should schools educate our children with FACT, or mere theory?'
Please list the things in science that you believe are FACTS, rather than 'mere theory'.


The 'evolution' of fruit flies is more scientifically supported than the supposed 'evolution' of humans from single-celled lifeforms.That is a bizarre way of looking at the results.

How about:

The evolution of animals which have very fast breeding cycles and can be studied easily is much more studied than the evolution of animals with very slow breeding cycles and with major ethical issues over deliberately causing mutations.

So far we have managed to reproduce many of the suspected stages of evolution:

* Change within a species: Done
* Creating new species: Done
* Introducing new features not present in the original generations: Done
* Observing DNA being generated from simpler chemicals (RNA): Done
* Observing RNA being generated from simpler chemicals (Peptides): Done

Mac
(PS: The 'Anything that cannot be fully explained by science, I accept as the Hand of God' principle is a very popular one historically. It is called 'The God of the Gaps'.)

kuwisdelu
02-22-2009, 09:26 PM
If our science classes only taught "facts," there really wouldn't be a whole lot to bother teaching... Might as well get rid of them.

Lhun
02-23-2009, 02:33 AM
Didn't have time for this post yesterday so i post this now.

Logic? Or mere observation? A logical error. Nothing to with observation.

But (changing my horse mid-stream etc because you has drownt the prettypony of my actual comment) the arrow of the Universe "POINTS" IN THE DIRECTION OF increasing Diversity and Difference. :)

Right?Wrong. ;)

I mean, isn't it fair to "observe" that things are getting more diverse and different, as Time progresses?Nope. That one's an error of observation, not of logic. First of all, before you can ever talk about complexity or diversity you have to define carefully what you mean by the words because they are used in very different ways depending on context. But anyway, to observe that the universe tends toward higher complexity is a a simple mistake. You see, whenever something starts out at the baseline of pretty much the least possible complexity it can only get more complex (or stay the same) so any change will increase complexity. The same mistake is often made when people talk about how evolution produces ever more complex creatures. When you start out with only unicellular things pretty the only way is toward more complexity.
And aside from that, it is also generally wrong. You can many changes from the complex to the simple in nature, be that evolving creatures or the universe in general. It's just that the complex is so much more noticeable to us humans since our brains evolved for pattern recognition. (When you see animal shapes in clouds, that's an example of your brain overdoing what it is supposed to do)
Now the logical error then stems from that. To see a partly real, partly fictional trend towards more complexity and diversity, and to think that this means it is the purpose of the universe. That is inferring teleology from ontology which is a categorical error.

If the Meaningfulness of All Existence demands teleology, then it is a coin I'll pay to have Meaning, yes ...Yes, meaning is a teleological property, but this means you cannot arrive at meaning from a purely ontological basis, which observations of natural world are. Meaning is in essence a purely human concept that cannot be found anywhere except where humans assign it. Sure another concious agent like a god could assign meaning too, but so far none has shown up to tell us about his purpose. And inferring this from observations of the natural world, even with the assumption of the gods existence, is invalid. And even assuming we had a god show up and explain his purpose, meaning is still a subjective concept, giving us no reason to agree to his meaning, or consequently to agree to any other humans concept of meaning.

As I mentioned above, many hold that Life and Awareness may ultimately shape the Universe to a greater extent than any of Science's blind "natural laws" acting blindly and randomly.Many might hold that, but so far i don't see it.

Logic. ha.
Life lives, and Logic scolds.In cases where logic fails it's usually not because logic as a tool failed, but because it was misapplied. It is a misconception to assume that just because all people think it is an action that does not need to be learned to do properly.

'Coincidence is God's way of remaining Anonymous' etc! :)If it is, he's doing a goddamn good job at it. ;)

Note: I don't know how the mods see the evolution discussion, but based on a lot of personal experience with such on the internet, i suspect it really should go into a seperate thread in the TIO forum. I withhold any comment on the issue in here because i just know it will derail and not unlikely turn the thread into a flamefest. ;)

small axe
02-23-2009, 04:43 AM
Originally Posted by small axe http://www.absolutewrite.com/forums/images/buttons/viewpost.gif (http://www.absolutewrite.com/forums/showthread.php?p=3315370#post3315370)
SOME life 'has evolved and continues to evolve.'
I suggest that you cannot demonstrate that ALL life 'has evolved and continues to evolve.'



Indeed.

However, that applies to everything. [quote]

You may need it to 'apply to everything' just so you can continue your comment. :) However, it only applies to the statement I applied it to, and to my statement you quoted.

You made an over-reaching statement about life and evolution.
I critiqued the validity of your over-reaching statement.
You quoted my reply.

And now you've over-reached again, trying to expand the issue into something about lead being denser than hydrogen (which obviously doesn't rebut my comment about life and evolution)

You said there can be 'no doubt' and I suggest that Science (to remain valid Science) can ALWAYS bring doubt to bear on a subject.

We needn't debate EVOLUTION versus RELIGION here (please, let's not)

We can legitimately discuss how not to make over-reaching claims though.

[QUOTE]
We observe that lead is denser than hydrogen. It makes sense and is logical and is consistent that all lead is denser than hydrogen .. but we haven't examined every lead atom in the universe.

Should we then refuse to teach the density of lead as a 'fact' ?


Why do you think you question applies to my quote?



Another example:
Kangaroos, Platypuses and Echidnas are native Australian animals. That is a 'fact', by any reasonable definition of the word.

However, should books on animals only report this as a 'mere theory' ?

After all, some people believe that Kangaroos, Platypuses and Echidnas once came out of a wooden box in Turkey, and then travelled to Australia. So by that belief they are not native to Australia.


See? You are dragging 'belief' in here ... and that is almost a challenge to take up the debate about Belief. :)

It's a debate that doesn't belong in this thread.

I don't know about the origins of Kangaroos etc (not my field of expertise or knowledge) ... but I'm open to the idea that marsupials might have originated outside of Australia, then survived there only because they were cut off from whatever pressures killed marsupials off everywhere BUT Australia.

Hence, not knowing for sure, I'd be careful before claiming they are 'native Australian animals' ... (If you 'know' they are, good for you; but I'd now be suspicious of over-reaching claims to knowledge etc)

Dinosaurs once walked in 'North America' ... but then one wonders: in what sense was it actually 'North America' if the continent as we name it didn't exist in its current form AS 'North America' ??? etc.

My point is: you bring 'belief' into a discussion where 'belief' may have no valid place. the belief of fools may be born in an unfortunate over-reaching acceptance ... which I'm here DOUBTING along with other over-reaching claims.



Should that theory be taught, or would you be happy with textbooks referring to 'Kangaroos are native to Australia' being reported as a fact ?

Again, I'd study the origin of Kangaroos more carefully before teaching their origin as 'fact' or not. You could be right, who knows? I hear horses "originated" in the New World then died out here. Then the Spanish brought them here again from Europe.
So would AZTEC science call horses "native" to the New World?
Would the European science of 1492?

See ... I can ask moot questions, too! :D



You asked 'Should schools educate our children with FACT, or mere theory?'
Please list the things in science that you believe are FACTS, rather than 'mere theory'.


Seriously?

'Cogito ergo sum' (on a good day, "Coito ergo sum') ...
That is seemingly a valid fact. Beyond that, maybe it's all Hinduism, Illusion, epistemology and existential uncertainty.

But me, I'm happy to admit it: the cat in the box is alive and dead and so let's not make over-reaching claims about the cat in the box, like either of us knows ... but the other guy is ignorant or superstitious.

Now ... Feel free to list for us YOUR LIST of undoubtable 'facts' :)

I bet there's a few people here who can cast a valid doubt on whatever you claim is beyond doubt, in your list.



Quote:
The 'evolution' of fruit flies is more scientifically supported than the supposed 'evolution' of humans from single-celled lifeforms.


That is a bizarre way of looking at the results.


Well, if it's true (which you seem to agree with), why is it 'bizarre' ???

Do we care what we think is 'bizarre' or what is true?

...




So far we have managed to reproduce many of the suspected stages of evolution:

* Change within a species: Done
* Creating new species: Done
* Introducing new features not present in the original generations: Done
* Observing DNA being generated from simpler chemicals (RNA): Done
* Observing RNA being generated from simpler chemicals (Peptides): Done


Those seem to apply to living creatures as we know living creatures now. So you're stating things about 'fruitflies' (and their equivalents: yes, we know about fruitflies, I said that)

None of that definitely demonstrates the evolution of humans from single-celled lower life forms ...

That's what schoolkids need to be taught about HUMAN EVOLUTION. That we can demonstrate some weird sh*te about fruitflies! :Hug2:



Mac
(PS: The 'Anything that cannot be fully explained by science, I accept as the Hand of God' principle is a very popular one historically. It is called 'The God of the Gaps'.)


Versus filling in gaps with mere assumption and theory ... and then teaching that as 'beyond doubt' ???

small axe
02-23-2009, 04:48 AM
If our science classes only taught "facts," there really wouldn't be a whole lot to bother teaching... Might as well get rid of them.

I should agree with you, I suppose, and pave the road to teaching my Saucer cult! :)

Alas, I cannot agree with you.

There is a world of knowledge to teach.

There are just a few extra caveats I'd throw in, too.

small axe
02-23-2009, 05:29 AM
But anyway, to observe that the universe tends toward higher complexity is a a simple mistake. You see, whenever something starts out at the baseline of pretty much the least possible complexity it can only get more complex (or stay the same) so any change will increase complexity.

Well, what you call 'a mistake' ... you then seem to agree is factual.

The Universe starts out unified and simple and becomes diverse and complex (if only due to the growing diversity)

Life starts out simple and the same (since we might guess we are speaking about Life starting with a single living thing) ... and becomes diverse and complex (in the way that six billion thinking humans are more diverse and complex than a single primitive creature, the SINGLE, FIRST creature)

Not to get personal, but the tact some are taking here seems (imo) to be to label my comments as 'wrong' or a 'mistake' ... but only by extrapolating my comments FAR BEYOND what I simply wrote.

That way leads to making empty 'straw man' arguments.

*shrug* No one is there yet, but it's a pointless path to depend upon, or to take.


The same mistake is often made when people talk about how evolution produces ever more complex creatures. When you start out with only unicellular things pretty the only way is toward more complexity.

That was my observation too: the trend seems towards complexity.

I'm not an absolutist about that, however. Some folks indeed suggest that a VIRUS is the simplified version of a once more-complex lifeform.

I don't doubt viruses 'evolve' either, by the way, so no one needs point out virus evolution as if I were unaware of that example too.

The evolution of viruses may be no evidence suggesting human evolution from pond scum, however.


And aside from that, it is also generally wrong.

Aside from being specifically correct, I was generally 'wrong' ???

Huh.