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Science

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1reading_fox
Editado: Fev 1, 2007, 6:39 am

I'll probably edit this a few times to get what I mean to say down correctly. It may be a bit long! It has come up a few times in the GD threads so here's what I want to say on the matter.

Science is several things. A method most of all. It is also a process - which is not yet, and maybe never will be, over

Some terms:
Evidence : observations, measurements. Things that have occured, preferably though seldom, indisputably.

Evidence is used to generate Theory a hypothesis about how the world may work. Theories have to be testable. If I do x under condition z, I will see y:

Assumption now we are starting to get into the tricky bits. This is all the z's in the theory, and everything else not mentioned! Some of these are what causes the greatest theories to fail. They are hardly if ever reported in the general media covering science but without them the conclusions (y) are invalid. Any failed assumption is enough to invalidate the theory.

Demonstration the process of testing a theory, actually doing the x, and seeing y. Please note the very important point this does not, I repeat NOT, PROVE ANYTHING It provides some evidence that the theory may be correct. Repeated demonstations, ad nauseum, do not prove anything either, they simply provide strong evidence.

proof : a formal mathmatical statement starting from the assumption (see above), that 1+1 =2. This is an assumption and cannot be proved, only demonstrated. There are many occasions when 1+1 = 10. Very few things are proven by science. Of course most proofs include previous proofs by others, such as Newtons "Laws" of nature. In using these you also agree to all the unwritten assumptions contained therein.

Law has no formal scientific meaning. A theory believed to be universally correct (ie very few assumptions), widely tested and always found true - within the limits of the equipment - so far.

Other things that are not proof Models . These are often computer generated, where a list of starting conditions are entered, calculations performed and a result announced. These are actually theories, and not tested theories either. How closely they predict real world scenarios is down to how accurate the underlying theory is - but any change in assumptions, missed starting conditions eyc, will render them invalid. They are very useful and are a powerful way for quickly and cheaply testing theories, but it must always be remembered that they are not the real world.

Arguments within science tend to be discussions on the appplicability of certain assumptions, or the repeatablility of experiments that provided evidence.

Arguments outside science tend to be based on the failure of one or both parties to understand the terms above, and poor journalism.

Good Scientific method.
Observe some evidence, propose a theory: VITAL STEP, test the theory. normally loop back and amend theory several times.
Publish - peers attempt to repeat experiments, and observe the same evidence, also examine theory for unwarrented assumptions. Assuming both are in agreement, the process of science is inched forward one notch.

Bad scientific method. observe some evidence, propose a theory. rush to journalist and funding body claiming to have proved something new.

New scientific discoveries come from observing new evidence - things never seen before - or discovering assumptions previously overlooked, or discounted.

Background reading: there's lots but the trouble with science by Robin Dunbar isn't a bad place to start. How to lie with statistics by Darrell Huff is very useful when looking at common media reports about "scientific" discoveries.

2Jargoneer
Fev 1, 2007, 6:37 am

Can I be mister pedantic here? Science is a method, methodology is the study of method.

Other than that, your explanation of the scientific model is perfectly clear and concise. Why do people find it so hard to grasp?

Talking about bad scientific method - The Guardian (UK newspaper) has a 'bad science' column highlighting exactly those issues you list.

3reading_fox
Fev 1, 2007, 6:39 am

Good point - I've edited that to now be correct.

4Hera
Fev 1, 2007, 7:15 am

I'm going to have to take notes on this. Me = dim Arts graduate wrestling with pencil and paper, but keen to learn.

5readafew
Fev 1, 2007, 10:29 am

The first problem is most people have never taken a Logic class and over half that have taken one barely squeeked a C. I had the second highest score in mine and I missed an 'A' by a couple points.

Many people do a grouping thing, 'a' is similar to 'A' so they are the SAME. No, they are not, they are similar, and can be used interchangable at times.

As I've tried to point out in other posts any aurguement/discussion should be started by difineing the important terms and any others that come up, to make sure everyone is starting at the same place and facing the same direction.

A good example... is a Democrat the same as a democrat?

Unfortunatly most people don't know how to argue just disagree.

6Jenson_AKA_DL
Fev 1, 2007, 10:31 am

Science was never my strong suit.

This might be off topic but I've always loved the idea of the Quantum Theory, at least based on my minimal understanding of it. Something to the effect that everything is interconnected. It always struck me as rather spiritual instead of scientific, but that could be my misinterpretation. Has anyone ever read Stephen Hawking and understood it? I keep trying to read about quantum physics but I can't wrap my brain around it. Is there a simple explanation that I've missed?

7readafew
Fev 1, 2007, 10:34 am

Mensagem removida pelo autor.

8reading_fox
Editado: Fev 1, 2007, 12:01 pm

#6 "Has anyone ever read Stephen Hawking and understood it? I keep trying to read about quantum physics but I can't wrap my brain around it. Is there a simple explanation that I've missed?"

We're outside, I'm not going to get snitty about a little offtopic ness.

Yes I've read Hawking. Yes I thought I understood most of what I was reading. No there isn't a simple explanation.

Note: I'm a chemist by profession, so whilst I've read an dealt with QP from time to time, I can't say my explanation? will be perfect.

First of all there's a very famous quote from someone I can't remember along the lines of "If you think you understand Quatum Physics, you're wrong!"

In the shortest form, it is the study and rules pertaining to matter at very small (sub atomic john gribben - its a book in my library I don't know why it won't touchstone. For a slightly more understandable version, though this book is now dated. There are sequals but I haven't read them. the Science of Discworld (not really by Terry Pratchett but often filed as if it were) also introduce quantum physics but I can't remember which of the three books it comes into. Looking at LTs author page it appears Gribben has written a lot of "public science" texts on various aspects of physics. If theya re all as useful as Cats he would be well worth seeking out.

I don't know considering my essay at #1 how much of this is proven, and where the assumptions lie. On the other hand a lot of testable hypothesis have been made, and their is a substantial body of evidence to support it. In the end it may prove to be more of a model than "real".

9readafew
Fev 1, 2007, 11:29 am

Hasn't there also been testing done suggesting that photons (light particles) don't exist in intervening space, but at the end point of its journey. source, destination, observation point?

I'll see if I can find something what I'm talking about.

10BTRIPP
Editado: Fev 1, 2007, 11:50 am

I believe you're referring the "wave/particle duality" which suggests that all subatomic entities "exist" as probability waves until measured; the measurement, in essence, extracting the "particality" out of the probability.

The classic experiment is the one-slit vs. two-slit target, where photons fired at a two-slit target will create an "interference pattern" on the recording surface behind the slits, indicating that what passed through the slits was a wave, whereas the one-slit target will simply fill up a space as though particles were being shot through the slit.

I just finished reading Kip Thorne's very interesting Black Holes & Time Warps in which he posits that all subatomic units have this dual nature.

11psiloiordinary
Fev 1, 2007, 11:53 am

Hi All,

A suggestion for the definitons.

Observe, propose a hypothesis, test it, if it seems to work at the moment call it a theory.

In other words there is a hierarchy of "we-think-this-is-rightness"

It goes;

some observed facts

hypothesis which generates a prediction and if proved right by more observed predicted facts

hypothesis becomes theory

i.e. the theory of gravity is of more use in describing the universe that a fact recording an apple falling

Just a thought.

Regards,

Mark

12reading_fox
Editado: Fev 1, 2007, 3:55 pm

Well that would be all massless "particles" yes.

edit: I'm not sure upon reflection that it is limited to massless particles now, I think it is all particles (even greater than atomic) travelling in a beam/wave thing.

I don't think it is fair to say that it IS a wave until measured as a particle. It is equally "true" that it is a particle unitl measured as a wave. In "reality" it is probably neither - a particle travelling in a wave or a wave broken up into small particles. ....

hey isn't science definitive!

And the "problem" with general perception of science is that the ambiguity seems to confuse journalists and they just convey the black view and the white view (in the interest of balance?!) but fail to understand/report the truth in the middle.

If they did the "public" might understand that there are very few hard and fast answers, which might lead to better comprehension of society all around. Or maybe more converts to religion where you can rely on an ancient hard and fast answer. :-(

13Eurydice
Editado: Fev 1, 2007, 12:06 pm

Reading_fox, while I am not the one who asked about quantum physics, thank you for a gracious, simple, and - for the forum - suitably lengthy response. Also, I quite appreciate the approach, and perhaps mood, in your first message.

Calm, would be one word for it. Reasonable and sane seem to me a couple of others. :)

I'm another who, for various reasons, never had a decent science education: and yet I do find it interesting, appealing, valuable - if not an oracle to be accepted blindly. It's clear, as little as I do know, how little that is touted as proof isn't susceptible of being argued or overturned: so I find you (and readafew, on defining terms) make excellent sense. (Incidentally, I had joined GD, but went Outside for a walk soon, as I found both the cheerful and not-so-cheerful discussions a bit noisy, in total. :) I don't think I even contributed.)

Converts to ancient religions are not a bad thing, provided we are willing to think and don't want to kill (or hate) those who disagree. But then, being one, what can I say? :)

14readafew
Editado: Fev 1, 2007, 12:04 pm

BTRIPP - YES!! However I think someone went one step farther and when TRACKING which 'slit' the photons went through (in the dual slit) the pattern reverted to the one slit pattern.

It was postulated that it had to do the 'observation' of the photon(s) that caused the change in behavior.

To me THAT is freaky cool.

15reading_fox
Fev 1, 2007, 3:53 pm

#14 what to me is equally unusual is that if you watch the interferance pattern and reduce the intensity such that there is only 1 photon involved - ie technically nothing to interfere with you STILL see the interferance pattern. QM is just ODD.

#13 Eurydice - Scientists are as human as everyone else, and dislike, as much as everyone else, someone disagreeing with "their" theories, I've made it sound calm but some scientific disputes have been very bitter, with participants not speaking to each other directly for the rest of their lives etc. However that wasn't your point. - Dogma is, I suspect, the biggest "enemy" of all, the attitude that " this is so because I say it has always been so." I can't blame, hate (or want to kill) anybody who has trully put some thought about how the world functioins and why one thing leads to another - and come to different conclusions. (They'd still be wrong of course ;-) but like MrsLee, I don't object to the company). It would be a very dull world if we were all the same.

16MrsLee
Fev 1, 2007, 4:33 pm

#15 - Since my name was mentioned...thank you for that clear definition. That is exactly why I don't think science can be used to prove or disprove faith. Science is interesting, mind-blowing at times and can certainly cause us to examine our beliefs and the world around us. A wonderful pursuit, if properly understood. And I agree with the statement that journalists can blow things out of proportion because of their need for the controversial soundbite.

17Jenson_AKA_DL
Fev 2, 2007, 11:30 am

>8 reading_fox: Thanks for the explanation.

I never did understand the cat thing. It was a "theoretical" experiment, right? I just found it facinating that so much stock was put into an experiment that never actually happened.

18reading_fox
Fev 2, 2007, 11:58 am

the CAT thing, I thought we get to this.

I believe it was Schrodinger but maybe Einstein, put forward a "mental experiment" regarding why QM is too weird to be true.

it goes thusly:
If you put a cat in a box with food and water and a vial of poison gas with a trigger, and set the trigger so that it is 50% chance of firing after a period of 1 day, based on whether or not an atom decays, what will happen?

According to QM and this duality stuff "explained" above, whether or not that atom decays is based upon whether or not anybody is looking - it is either a wave or a particle, until you look - hence in QM speak it is both.

Therefore the cat after one day is both alive and dead. At the same time. until you look.

Silly right?

Yes. and No. Its theoretically both regarding the mathmatics that model whether or not that atom decays. In practice, quantum mechanical waveforms collapse at larger scales into observable realities - I like that phrase and I just made it up too - so the cat either remains alive, or dies from the poisen, you can't tell until you look. If it were just an atom it may continue to behave in both modes.

I'm not sure I've made this any clearer. Its not an easy subject.

19BTRIPP
Fev 2, 2007, 12:06 pm

I think the essence of the "Schrodinger's Cat" thought experiment is that mathematically, the cat must either be in an indeterminate state of being both live and dead until observed by the experimenter, OR be both live and dead, with the universe having split into two separate reality tracks. In practice (not that I've ever heard of it being performed), I would think that the cat's observation would be sufficent to "collapse the probability envelope"!

Needless to say, while being mathematically coherent, most people reject the "multiverse" interpretation, as the levels of complexity involved (given the endless plethora of randomized outcomes which would provide "splitting points") is truly staggering.

20readafew
Fev 2, 2007, 12:08 pm

I've heard along the lines you have the POTENTIAL to be in either univese (the cat lives, or dies) at the time you OBSERVE one or the other your universe is known and the POTENTIAL has been spent.

Which can beg the question, can one choose?

21myshelves
Editado: Fev 2, 2007, 12:17 pm

The Cat:

Fascinating. I had a vague grasp of it, but y'all are good teachers!

Btw, why does science need to be "taken outside"? Has it come to that? Are we in Kansas, Toto? :-)

22MrsLee
Fev 2, 2007, 12:56 pm

Possibly because it's not fiction or fantasy (depending on your view :)), and people are trying desperately to get the pub back on an even keel. Don't rock the boat. I don't think the intent of the Green Dragon was to discuss every subject, and the one special thread/room thing didn't seem to work for some, it was offensive, so better to start a new pub with every topic speakable.

23Jenson_AKA_DL
Fev 2, 2007, 2:21 pm

I always thought that the experiment had to do with the actual physical effect of radiation on a physical being (the cat). This probably explains a lot as to why I didn't get it. I didn't realize that it was more of an exercise into the theory of alternate universes with a duality of outcomes.

It seems like every account I've read of the experiment put so much emphasis on how the experiment would be conducted if it were to really happen (for the cats sake, I'm really very glad it never did!) I never got past that part of the explanation.

Thanks!

24myshelves
Fev 2, 2007, 2:51 pm

Mrs Lee,

Not trying to rock any boats. The Green Dragon says it is for Fantasy, Science Fiction, etc. (Or is it really intended just for fantasy?) Science is a big part of science fiction --- obviously. (When I started reading it I used to call my friend's husband, who had taught physics, to get some of the concepts explained.) I honestly can't imagine why a science thread wouldn't be appropriate in the Green Dragon. I'd expect Schrodinger's cat to have a place by the fire.

25BTRIPP
Editado: Fev 2, 2007, 4:00 pm

re: #23 ...

Yes, the only "radiation" involve in Schrodinger's Cat is a radioactive source which had a 50/50 chance of having a "decay event" in the given time ... were there to be a decay, a monitor (geiger counter, etc.) would have signaled the fact, and that signal would have been what would have triggered what ever device (i.e. a spring-loaded hammer) that would have broken the vial and released the poison gas.

26reading_fox
Fev 2, 2007, 4:41 pm

Great picture BTRIPP.

I started Science outside, as a place for me to vent about how it should be communicated, as the long posts involved didn't seem to fit with the religious discussions.

I've got a fairly broad though not necessarily deep understanding of most of the common topics and when I feel like it I'll add posts on proving a negative and faith and also evolution (though that did get covered just about in the religion threads)

27myshelves
Editado: Fev 3, 2007, 12:58 pm

Oh. Ok. It just looked odd when I found the thread.
I had this picture in my mind:
"We're gonna talk about the scientific method and quantum physics."
"Yeah?" growls the barkeep, "Then take it outside!" (Grin)

28readafew
Fev 2, 2007, 6:43 pm

I see a little white girl in the middle of the ghetto, late at night with Quantum Physics books... she's going to start something

29Jenson_AKA_DL
Fev 3, 2007, 8:22 am

Will Smith gets some great lines, doesn't he?

30readafew
Fev 3, 2007, 8:59 am

Absolutly! 8)

31geneg
Editado: Fev 10, 2007, 11:37 pm

#6 Demonlover

I find quantum mechanics very spiritual, and imy own spirituality has been affected through my most limited knowledge in a layman sort of way. Two books that bring a spiritual approach of the "everything is connected" variety to QM are The Tao of Physics by Fritjof Capra and Dancing Wu-Li Masters by Gary Zukav. Both of these books are from the late '60's early '70's so some of the specifics may be out of date, but the popularly understood aspects of QM haven't changed that much.

Another book that I found very useful, but a lot more detailed and mathematically oriented is The Elegant Universe by Brian Greene.

As for the duality/many universes theories, I understand the underlying ideas, but the quantum realm, like the rest of existence, is subject to entropy and QM creates complexity through self organization in it's constant battle against entropy. At each level of complexity another set of potential universes falls by the wayside. By the time enough complexity has evolved that observation is possible the observed is firmly planted in this universe, begging the question that, given the nature of self organization is this universe the only possible universe?

If Brian Greene is correct with his superstrings, by the time the quantum realm emerges things have passed the multiple universe stage anyway.

Anyway, I hope this gives you some direction.

32Jenson_AKA_DL
Fev 12, 2007, 7:25 pm

Thanks! You're the second person who recommended The Tao of Physics to me. I'll have to check it out.

33reading_fox
Fev 14, 2007, 8:55 am

For those who want a novel about/involving the scientific method, how it works and how it doesn't, try:

Kim Stanley Robinson's Forty Signs of Rain which I am finding absolutely stunning. I don't know when it si set or how accurate the Climatic predictions are, but all the rest of the science is spot on. In addition the feel for the climbing is also very realistic!

34MrsLee
Fev 18, 2007, 12:59 pm

Now this is my kind of science. :D

http://www.peepresearch.org/index.html

35lorsomething
Fev 21, 2007, 8:29 pm

I just scanned the posts, so might have missed some point that speaks to mine. I have no credentials, but I love science. Duality is a condition of the universe, as I see it, so I was not surprised that light probably also has a dual nature. I think science is like a baby, running around wild and sticking its fingers into things. But it has some growing to do. Much of what is postulated by scientists cannot be proven empirically, so there is an element of faith in science, as well. That's one of the things I love about it, though. If we had all the answers, it would be a dull ride, wouldn't it?

36iphigenie
Editado: Mar 9, 2007, 2:14 pm

#31

I must say I cringe when i encounter any of the theories that try to extend quantum theories to mind and religion. The philosophies they want to promote might be good and enlightening, who knows? but using science to try to give authority to them is just plain wrong.

Most of them take concepts which for most people are still fuzzy and confusing, jump to "it therefore means this for our minds/souls" with all the authority of scientific language.

It's all mumbo jumbo. Even if in their thinking, looking at the science made them connect some dots and get a religious experience, it does not mean that the science in questions "proves" the religious or philosophical truth of their insights.

The one exception might be David Bohm, but then he never really reaches any conclusions, I don't think.