Welcome to European Tribune. It's gone a bit quiet around here these days, but it's still going.
Display:
They're just complementary qualities. You could call them red and blue, day, night, zombo and fruvious.

(In fact quarks are divided up into 'colours' which are just another example of complementary qualities, grouped in threes instead of twos, and don't imply actual colour.)

It works like this - things behave in a certain way, and you have to label them with something. So historically scientists pick a word that sort of fits - often not very well, and sometimes out of context - and leave it at that. The people who do the exploring get to choose the words. If their exploring is good, everyone else copies them. If the words are not so good - too bad, everyone is stuck with them.

But you've illustrated a point I've tried to make before about the difference between scientific and creative types.

Creative types view the world through their feelings, and feeling is a moral process. So if they're excited about something - that's good. It's positive! If they're not excited about it - and feeling negative - that's bad.

Scientific types just describe what happens. There's no moral imperative, and while they do excited about things, getting excited - or not - isn't the main point of the exercise. The main point is describing what happens accurately, precisely, and reliably.

So with charge what matters is that opposing charges attract, and identical charges repel. You can put some numbers in and calculate exactly how much this happens.

E.g. to make an old-style cathode ray TV or monitor, you need to flick a beam of electrons around to paint the picture. Because you know the charge, it's easy to calculate how much flicking is needed, and how to build something that does it.

And - this would still be true if you went through the whole of physics and swapped the negative and positive signs around.

The current (sorry...) convention is actually rather stupid, because in a battery electrons flow from the negative terminal to the positive one. So if you think of it in terms of water flowing - which is sometimes useful for electricity - there's a flow from negative to positive.

This makes no sense at all, and it's really just an accident of history that the labelling is as it is.

by ThatBritGuy (thatbritguy (at) googlemail.com) on Fri Mar 14th, 2008 at 10:48:25 AM EST
[ Parent ]
Great comment, thanks!

If the words are not so good - too bad, everyone is stuck with them.

Ah!  You have felt my pain.

this would still be true if you went through the whole of physics and swapped the negative and positive signs around.

I read an example where they used green and red balls--precisely to remove the associations with the words "positive" and "negative", but then the red balls and the green balls did different things (the red balls clumped together and the green balls flew around them, I think), so there was some essential difference between a red ball and a green ball; you could change the colours but that difference was still there.  I'm looking for a model where I can assign some concept to "red ball" (apart from redness) such that the behaviour of the red ball can be (at least partly) anticipated by my associating my model...."Those red balls are like...diamonds, hard to the touch and expensive; those green balls are like....cars; always around and needing roads...."

Creative types view the world through their feelings, and feeling is a moral process. So if they're excited about something - that's good. It's positive! If they're not excited about it - and feeling negative - that's bad.

Scientific types just describe what happens. There's no moral imperative, and while they do excited about things, getting excited - or not - isn't the main point of the exercise. The main point is describing what happens accurately, precisely, and reliably.

Would the two words "qualitative" and "quantitative" apply here?  I mean, I can do both but I need the "qualitative" so that I can keep my "quantitative"...in some human context...I can see a synthesis whereby the scientific description (accurate, precise, reliable) can only be brought into human action (lives....I dunno ....into the realm of human....something) when effective models are in place for us to relate the numbers to something less abstract (as is happening at the moment--for me--with the great discussions here and across the internet about economics); and vice versa those that can simply feel something need to be able to turn these feelings into something quantitative so that one person's experience can be spread out across humans (human society...something like that.)

Don't fight forces, use them R. Buckminster Fuller.

by rg (leopold dot lepster at google mail dot com) on Fri Mar 14th, 2008 at 11:26:04 AM EST
[ Parent ]
IEEE - IEEE History Center: FAQS
In the 18th century a number of people made investigations of static electricity. Charles Dufay distinguished between vitreous electricity (the sort created when glass or rock crystal was rubbed) and resinous electricity (the sort created when resin or a wax rod was rubbed). Dufay proposed a two-fluid theory of electricity, the two fluids corresponding to the two types of electricity. Benjamin Franklin proposed a one-fluid theory, hypothesizing that the two apparent types of electricity were, in fact, occurrences of excesses and deficiencies of a single electrical fluid. Franklin introduced the terminology 'positive' and 'negative' to denote, respectively, an excess of electrical fluid and a deficiency of electrical fluid. It was on the basis of certain charging and discharging phenomena that Franklin assigned the designations 'positive' and 'negative', and in the 19th century the terminals of electric batteries were labeled 'plus' and 'minus'. Early in the 20th century it became clear that in most instances of the transfer of electric charge, it is electrons (negative charge carriers) that move, but by then the labeling conventions were firmly established.


Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Fri Mar 14th, 2008 at 11:46:54 AM EST
[ Parent ]
I think qualitative and quantitative happen later. The key point is really that it's about how you feel, and creative types tend to use their feelings as a guide for making sense of reality.

In my experience creative types approach a problem by asking themselves how they feel and making connections between things, and it's the process of finding things that look like other things and assuming they're connected that keeps them interested.

Scientific types systematise. They like numbers and abstractions, and algorithms to glue them all together.

It's very hard to do both at the same time, and individually both are partial and incomplete.

If you just do the algorithms you can lose the plot and spend time building a system that either doesn't work or doesn't answer the question that really matters to people. If you just do the intuitive feeling stuff you can mistake feeling for understanding - because feeling isn't really a useful model or system, it's a fleeting experience.

What makes science and maths hard is that sooner or later you have to stop relying on trying to experience what you're trying to understand. When the maths gets really hard, you can't do that any more. You start from somewhere familiar, blunder around a maze of twisty little equations bumping into things and feeling blind, and - ideally - fall out the other end into somewhere that makes sense again.

I've always had problems at that point. I suffered through maths A Level making very little sense of mechanics because the teacher hadn't bothered to make a simple connection to things I'd learned earlier. Once I got that, it became easier.

The more advanced the science, the harder it is to be physically intuitive about it. Some rare people seem to have a kind of mathematical intution which is a substitute, kinda sorta.

But I don't, and a lot of professional scientists don't seem to either.

And therefore - hard. Sometimes hard maths is abstracted to make it simpler and more intuitive to work with again.

But you can still end up with:

Which is not necessarily intuitive to most people. ;)

by ThatBritGuy (thatbritguy (at) googlemail.com) on Fri Mar 14th, 2008 at 12:16:08 PM EST
[ Parent ]
but then the red balls and the green balls did different things (the red balls clumped together and the green balls flew around them, I think), so there was some essential difference between a red ball and a green ball; you could change the colours but that difference was still there.

That, at least partly, is because the model you're using is so simplified.  It can't hope to explain why the protons stick together, because they shouldn't.  They're all positively charged and so should repel each other and fly apart.

(Don't worry yet about why they stick together.  Just accept that it gets more complicated later on.)

The terms positive and negative were applied consistently to charge before the discovery of the electron.  Unfortunately this turned out to be the wrong way round for easy visualisation.

A rather value-loaded metaphor I think I've just made up is that when you're positive, you attract what you need, and when you're negative, you lose.

But, really, I visualise electrons a bit like little packets of negative charge.  And because I know electricity is a flow of electrons, it's therefore logical that it flows from maximum to minimum, ie the negative to the positive electrode.

If an ion is negative, it's because it's got an extra packet of negative charge...

And...read this slowly...you already know that two minuses make a plus.  Minus "minus one" is one...if an ion is lacking an electron, it will be minus one unit of negative charge.  Therefore it will be positive.

I hope this makes sense...  :)

by Sassafras on Sat Mar 22nd, 2008 at 05:03:12 PM EST
[ Parent ]
It can't hope to explain why the protons stick together, because they shouldn't.  They're all positively charged and so should repel each other and fly apart.

They don't. Two protons can never form a nucleus. That's what you have neutrons for (or rather, that's what neutrons do, if we want to avoid the pitfall of anthropocentrism). If you want a toy model that'll serve you well enough and remain useful pretty far into your studies (if not forever, depending on your line of enquiry), you can think about neutrons as a kind of glue that holds the positively charged protons together.

And by the time that model is no longer adequate, protons, neutrons and electrons should be such familiar mental constructs that they have long transcended the initial toy model.

- Jake

Friends come and go. Enemies accumulate.

by JakeS (JangoSierra 'at' gmail 'dot' com) on Mon Mar 24th, 2008 at 11:15:45 AM EST
[ Parent ]

Display:

Occasional Series