Intuitive Physics: What Is It?

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In summary, "intuitive physics" is a research field in Developmental Psychology that studies the pre-verbal understanding of physical concepts and laws in children. It aims to explore the cognitive roots of physics and how they may differ across different cultures. While these intuitive concepts may form the basis for later understanding of physics, they are not considered to be actual physical models or laws. This research also suggests that a rich sensory experience of nature in childhood may provide a foundation for learning physics later in life.
  • #1
Carla1
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What is intuitive physics?

Thanks in advance.
 
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  • #2
seems to be a research topic in Education and Developmental Psych

I had never heard of an academic study area called "intuit. phys." until seeing your post. I put "intuitive physics" into google and got links to a bunch of research done in Developmental Psychology in places like Berlin and Zurich.

The idea is there is a certain amount of physics that you pick up as an infant or child which doesn't involve any MATH and may even be be BEFORE LANGUAGE.

(I know Piaget studied children learning certain physical concepts at pre-school age----he studied that long long ago, so maybe people would say he began the study of "intuitive physics". Wasnt Piaget Swiss?)

If some learning of physics concepts and facts is prior to language then it perhaps would not even depend on what CULTURE the child is raised in. One can explore the pre-verbal development of physicsal understanding in two different cultures to see how much is cultural and how much is even more basic. Here is an example of a cross-cultural study in I.P. done in Berlin and in Trobriand Islands South Pacific. The following quote is from
http://content.mpiwg-berlin.mpg.de/ECHO_content/content/children [Broken]

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Studying Intuitive Physics in two Cultures


Intuitive Physics
Physical knowledge significantly predates any systematic theoretical treatment of physics. The most basic knowlegde presupposed by theoretical physics is based on experiences acquired almost universally in any culture by human activities. It includes the perception of material bodies and their relative permanence, their impenetrability, their mechanical qualities such as heaviness or hardness, as well as their physical behavior. The outcome is an „intuitive physics“ which is built up in ontogenesis and guides human activities related to our physical environment.

A Cross-Cultural Study on Intuitive Physics
In view of the lack of sufficient empirical evidence on the universal character of intuitive physics, a study was carried out at the Max-Planck-Institute of the History of Science, including field research both in Germany and on the Trobriand Islands (Papua Newguinea). Interviews with 56 German school children were conducted with the aim to analyze the ontogenetic development of intuitive conceptions of life, force, motion and weight. In order to examine which aspects of intuitive physical thinking and its development might belong to universal cognitive structures, a parallel investigation was carried out in Kiriwina (Trobriand Islands). The same tasks given to the German school children were administered to Trobriand children and adults. To control for possible influences of schooling, two groups were studied; the first group consising of 31 children the Catholic mission school in Gusaweta, and the second group consisting of 41 children and adults from a remote Trobriand village (Iuwada) with no school.


... In order to explore concepts of motion and its causes, five tasks were utilized. For the assessment of concepts of throw, collision and horizontal motion, one task was administered, respectively. Two tasks aimed at conceptions of fall. To assess criteria for the inanimate/alive distinction, one task was administered. In order to study concepts of weight, six tasks were used. One task aimed at the idea of weight conservation, one task - Floating and Sinking - involved judgments about the behaviour of different objects in water, one task aimed at the relation of matter and weight, and three tasks tested an extensive idea of weight...
--------------------

I am not saying that research in "Intuitive Physics" is good or interesting. I just heard of it this minute, from you.

Before now, when I say "please give me an intuitive explanation of what energy is, please give me an intuitive idea of how an electric motor works..." I mean something different. For me "intuitive" means NON-TECHNICAL, non-mathematical, using plain language and commonplace images and ideas we all share. For me, physics is physics and "intuitive" is just a STYLE of explanation. So it is not an academic research area! Maybe it is silly to turn it into an academic field of study! I can't say. But GOOGLE thinks it is a research field in Developmental Psych.
 
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  • #3
I see. Thanks. So you would not say intuition is the basis upon which all constructed physics models ultimately rest, I think, if I am reading you correctly. If that is correct, upon what basis do they rest, in your opinion?
 
  • #4
Originally posted by Carla1
I see. Thanks. So you would not say intuition is the basis upon which all constructed physics models ultimately rest, I think, if I am reading you correctly. If that is correct, upon what basis do they rest, in your opinion?

I suspect that YOU have some ideas about the cognitive basis of mathematical models of nature. So I should be asking YOU to reveal some of your thinking about this, not the other way around!

You asked: what is "intuitive physics"? I reply that according to Google it is a research field in Developmental Psych. (the study of how children acquire social behavior, skills, language, culture, personality or whatever it is they acquire.

You should come out with your ideas. I will help by giving you some "traction"---some gravel so the road is not so slick---if you want. But I have not thought about it.

I think physics mainly involves mathematical models of nature that let one predict the results of measurements----or anyway the measurements let one refine the parameters in the model.

The quantities in the models have roots in childhood experience----like volume, hard, soft, bigger, smaller, fast, slow, area, length, color, balance, push, swing, bounce, fall, liquid, bubble, musical pitch.

One learns some basic physical properties sometime in childhood probably in the same years that one learns spoken language.

But these are not physical models or laws. They are at the cognitive roots but they are not physics. They are also at the cognitive roots of mathematics (which is about other things as well as number).

A child who gets a rich sensory experience of nature will have
RESOURCES to learn physics later in life, and yet may not learn--may chose to focus on other things.
The job of the physics teacher is to tap into the fund of experience in a way that vitalizes the laws.

BTW the laws are not absolutely true. They get improved-on from time to time. But they are the best we have for the time being and they do work rather well for many purposes.

Experience is more true (my feeling is) than laws. You either went skiing or you did not. You felt certain things. You fell while going down the ski-slope or you did not.

the physical model that is applied to experience is subject to change---Aristotle and Newton would have explained skiing differently, and scuba-diving too, no doubt.
 
  • #5
If you want to think about the relation of experience and natural language to physical models, maybe it would be good to go back to one of the earliest.

Aristarchus (250 BC?)

he realized that the sun was much much bigger than the Earth and
set up a heliocentric model (earth and planets going around sun) to compare with what he and others could see

Archimedes read Aristarchus heliocentric model and discussed it in a book written for the child of a friend of his---a book intended to teach about the relative sizes of things in the universe.

Copernicus later discovered much the same thing.

Everybody had always seen the sun and seen the moon. This is experience.
To say that one is a lot bigger than the other is mathematics (of a very simple kind) or anyway borders on math.

To make a model with E going around S, and day/night being produced by Earth ROTATING instead of sun rising in east and flying across sky and setting in west, this is an early act of physics.

It is not rooted in experience. The experience of seeing sun and moon in the sky we all had for a million years. What he did was physics, not experience, and required drawing a geometrical model (in the sand, on papyrus, in a computer)

He drew a picture and counted the days the moon took from quarter to quarter and from this DEDUCED that the sun was very far away (much farther than the moon, and thus much bigger) which was not something that one can simply look up in the sky and experience.

And so I say that physics is a quirky peculiar activity that is different from universal primitive human activities that we invariably get around to in the course of living life. A person can live their whole life (and live a good full life) and never ask a physics question or have a physics insight. There did not have to ever be a person named Aristarchus
 
  • #6
He drew a picture and counted the days the moon took from quarter to quarter and from this DEDUCED that the sun was very far away (much farther than the moon, and thus much bigger) which was not something that one can simply look up in the sky and experience.

If you mean Aristarchus did that, the facts are a little different. Aristarchus figured a way to get the relative distances of the sun and moon by observation. He reasoned that at the exact moment the moon is half full, the line from the moon to the sun makes a right angle with the line from the moon to the earth. Thus the earth, the moon, and the sun form a right triangle, with the right angle at the moon, and the earth-sun distance as the hypotenuse. So if you measure the angle between the Moon and the Sun at that exact moment, the ratio if the moon's distance to the sun's distance will be the cosine of that angle. Yes they did know how to solve right triangles in his day, although Aristarchus would have used a "chord" function instead of a cosine.

The actual measurement, as you can see is fraught with difficulties and sources of error. Aristarchus got a wrong figure, sun distance >= 30 times moon distance (the actual ratio is close to 400 to 1). His figure was enough to set him off though, since it was already known that the moon is about a quarter the size of the earth, so the sun would be over 30 times that or 7.5 the size of the Earth (in diameter, 421 times the Earth in volume). Such a big ball couldn't swing through the sky every day, and so...
 
  • #7
definition of intuition:
a first or primary truth.

definition of physics:
The study of the natural or material world and phenomena; natural philosophy

logically putting these two together as a single definition, i would interpret as the human being's ability to "know" the primary truth of physics before being conditioned with traditional education - which may (or may not) lead a student away from the basics or away from the primary guiding truth within that helps us understand the laws of our universe...
 
  • #8
Originally posted by marcus
I suspect that YOU have some ideas about the cognitive basis of mathematical models of nature. So I should be asking YOU to reveal some of your thinking about this, not the other way around!

You asked: what is "intuitive physics"? I reply that according to Google it is a research field in Developmental Psych. (the study of how children acquire social behavior, skills, language, culture, personality or whatever it is they acquire.

You should come out with your ideas. I will help by giving you some "traction"---some gravel so the road is not so slick---if you want. But I have not thought about it.

I think physics mainly involves mathematical models of nature that let one predict the results of measurements----or anyway the measurements let one refine the parameters in the model.

The quantities in the models have roots in childhood experience----like volume, hard, soft, bigger, smaller, fast, slow, area, length, color, balance, push, swing, bounce, fall, liquid, bubble, musical pitch.

One learns some basic physical properties sometime in childhood probably in the same years that one learns spoken language.

But these are not physical models or laws. They are at the cognitive roots but they are not physics. They are also at the cognitive roots of mathematics (which is about other things as well as number).

A child who gets a rich sensory experience of nature will have
RESOURCES to learn physics later in life, and yet may not learn--may chose to focus on other things.
The job of the physics teacher is to tap into the fund of experience in a way that vitalizes the laws.

BTW the laws are not absolutely true. They get improved-on from time to time. But they are the best we have for the time being and they do work rather well for many purposes.

Experience is more true (my feeling is) than laws. You either went skiing or you did not. You felt certain things. You fell while going down the ski-slope or you did not.

the physical model that is applied to experience is subject to change---Aristotle and Newton would have explained skiing differently, and scuba-diving too, no doubt.


I do have some thoughts about that which I am asking on but I'm really, at this point, attempting to clarify for myself, the philosophical basis of physics. For that, I need to develop an understanding of how physicists themselves view physics. I have obtained a picture of physics as being a system devised on the basis of logic and reasoning, as a way of understanding phenomena in relation to phenomena.

The result of that cognitive processing (logic/reason)has been the development of a highly sophisticated language, namely, mathematics, to symbolise relationships between phenomena. As you are aware, language itself is symbol and affects how phenomena are observed and even experienced. A good and well-known example of this is the difference between how those from extremely cold, snowy climates experience snow and how those from warmer climates experience snow. Those from snowy climates may have a linguistic access to the experience of snow which is much broader and subtlely descriptive than those from warmer climates. For the warm-climate person, snow may simply be white and cold, possibly even pretty. For the snow-acclimatised person, snow might be grey, white, heavy, light, pelting, driven, floating...you get the picture (I am probably not using the exact terms used).

Do you think there is a possiblity that the highly-specific mathematical language of physics actually affects the experience of the language-user, of the phenomena and do you think it is possible that models of the universe humanly-constructed over the past couple of thousand years, have affected the experience of existence in cultures in which those models have become commonly accepted?

Thanks again.
 
  • #9
Originally posted by Carla1
Do you think there is a possiblity that the highly-specific mathematical language of physics actually affects the experience of the language-user, of the phenomena and do you think it is possible that models of the universe humanly-constructed over the past couple of thousand years, have affected the experience of existence in cultures in which those models have become commonly accepted?

this is going too far afield for me
maybe you are in UK and I am in urban California
we have a different cultural ambience

suppose we narrow it down to one thing: the night sky

suppose I go to a remote village in mexico and try to find out how people experience the sky

and then I go out in my city some evening and try to find out how people experience the sky

it might make me sad and confuse me to do this (people in my city mostly cannot see the sky and have very little idea how wonderful it is) but suppose i do it---ask questions, make notes

then suppose I try to relate the difference to some 2500 years of Greco-European mathematics.

Your conjecture is that there would be some clear correlation. The sky-experience of my fellow citizens would differ in a clearcut way from that of the villagers and this clearcut difference would be partly explainable by there having been 2500 years of G-E mathematics.

I suspect not. So this is depressing.

However, on a more cheerful note, any language that you USE a lot, especially with children, CAN expand experience. If you use a rich vocabulary in describing snow and sensations associated with different kinds of snow, the kid will have a richer experience and be able to see more beauty in snow. Same with stars and the night sky I guess---like, the tracks of planets are evidence of a certain geometry, the milkyway shows the geometrical layout of our galaxy, you can point out where the center of the galaxy is, you can visit telescopes etc---these are ways to enrich the experienc of the sky and ways that language (including math ideas like "center" of a pancake shaped galaxy) enhances beauty.

but most people have little experience of mathematics in their language, cannot sing 4-part harmony but prefer to watch other people singing on television, do not vote in elections, and so on
they have voluntarily abandoned the 2500 yr GrecoEuropean culture, with its history of democratic participation in city life, geometry, polyphonic music, astronomy, enjoyment of numbers, theater, dance.
they watch other people dance on television
they watch a movie about a mathematician who likes numbers but do not experience numbers
the night sky overhead usually has a hazy glow that only a few stars get thru so usually we are not really seeing the stars either

i would rather not discuss this.

there is a nice book called "Coming of Age in the Milky Way" by Timothy Ferris. the 2500year history of the expansion of cosmic perspective. every step along the way was made by a passionate human being. each step is of enormous value. who first discovered the distance to a star? who? how? this is our heritage but most of us don't know it. why discuss this in generalities Carla? read the book and learn every step of the way by which we came to know that we live in our galaxy
 
  • #10
Originally posted by marcus
this is going too far afield for me
maybe you are in UK and I am in urban California
we have a different cultural ambience

suppose we narrow it down to one thing: the night sky

suppose I go to a remote village in mexico and try to find out how people experience the sky

and then I go out in my city some evening and try to find out how people experience the sky

it might make me sad and confuse me to do this (people in my city mostly cannot see the sky and have very little idea how wonderful it is) but suppose i do it---ask questions, make notes

then suppose I try to relate the difference to some 2500 years of Greco-European mathematics.

Your conjecture is that there would be some clear correlation. The sky-experience of my fellow citizens would differ in a clearcut way from that of the villagers and this clearcut difference would be partly explainable by there having been 2500 years of G-E mathematics.

I suspect not. So this is depressing.

However, on a more cheerful note, any language that you USE a lot, especially with children, CAN expand experience. If you use a rich vocabulary in describing snow and sensations associated with different kinds of snow, the kid will have a richer experience and be able to see more beauty in snow. Same with stars and the night sky I guess---like, the tracks of planets are evidence of a certain geometry, the milkyway shows the geometrical layout of our galaxy, you can point out where the center of the galaxy is, you can visit telescopes etc---these are ways to enrich the experienc of the sky and ways that language (including math ideas like "center" of a pancake shaped galaxy) enhances beauty.

but most people have little experience of mathematics in their language, cannot sing 4-part harmony but prefer to watch other people singing on television, do not vote in elections, and so on
they have voluntarily abandoned the 2500 yr GrecoEuropean culture, with its history of democratic participation in city life, geometry, polyphonic music, astronomy, enjoyment of numbers, theater, dance.
they watch other people dance on television
they watch a movie about a mathematician who likes numbers but do not experience numbers
the night sky overhead usually has a hazy glow that only a few stars get thru so usually we are not really seeing the stars either

i would rather not discuss this.

there is a nice book called "Coming of Age in the Milky Way" by Timothy Ferris. the 2500year history of the expansion of cosmic perspective. every step along the way was made by a passionate human being. each step is of enormous value. who first discovered the distance to a star? who? how? this is our heritage but most of us don't know it. why discuss this in generalities Carla? read the book and learn every step of the way by which we came to know that we live in our galaxy

I'll look out for the book; it sounds like it would be a good, informative read. I agree utterly with you about city night-skies being a depressive thing. I live in Australia with its fair-share of smogged night-views. However, when you get out to some of the more remote parts, the night-skies are awe-inspiring, as I imagine can be found in remote parts all around the world.

You seem to have answered my question. There is no such thing, at least, scholastically speaking, as an intuitive physics. But you have pointed me in the direction, nevertheless, that such a thing does exist. It can exist as a spring-board, in experience and may draw heavily upon reason but is not necessarily shackled by reason. That is a good thing. If reason assists in enlarging understanding and experience, rather than shrinking either, that can only be a good thing.
 
  • #11
I just realized I included your entire quotes in the last two my posts. That can be ruly annoying...sorry 'bout that.
 
  • #12
Originally posted by Carla1
I just realized I included your entire quotes in the last two my posts. That can be ruly annoying...sorry 'bout that.

And I just realized I've been talking too much---should leave space for Kerrie and/or selfAdjoint to say more about intuitive physics if they've a mind to. So I erased some superfluous loquacity.
 
  • #13
No need for such dramatic displays of humility. Why deny your readers the right to make up their own minds as to whether what you have to say is worthy of reading?
 
  • #14
Hello Carla, glad you are still around
I think the topic "intuitive physics" has some possibilities for
discussion---tho you seemed satisfied about yr earlier question
and we reached closure on that.

I think there is something to explore here but I don't know what it is,
and so I don't know what to ask or specifically talk about

some ideas from Kerrie and/or selfAdj. might help. other people's perspective often helps

Here's something: many things in physics are like the distance to the sun.
it is an important quantity, really pivotal! but you can't just look up in the sky and see it

the fine structure constant alpha---a number somewhat like pi---is a proportion in all atoms. it is a deep proportion in nature and inherent in life chemistry and the rate the sun gives out energy and all that, very pervasive---but you can't just look at some material (a tree, some bread dough) and see it. You can SEE pi just by looking at a circle and seeing the ratio of circumf to diameter. but the ratio alpha is also in things but not directly visible

I have this intuitive feeling about physics that what is distinctive is the HIDDEN proportions in nature, the deep proportions that (on the one hand) are very important to the workings of life and shining of stars and motions of planets etc. but (on the other hand) aren't immediately obvious.

the distance to the sun is clearly important, if it was too close we burn up and if too far we freeze and the whole choreography and timing of things depends on it and it is the yardstick for visualizing stuff (the "astronomical unit"---jupiter is 5 AU out, 5 times the Earth's distance, and neptune is 30 AU out, and so on)
but for a long time no one even thought to ask how far the sun is!
The distance is important but invisible!
 
  • #15
Here is another hidden number (also very basic)

It is Kepler's number 2/3
or you can look at reciprocally as 3/2 as he did
He called it "sesqui" which means "one and a half" in Latin
but however, this number is infused throughout the solar system, it is
intrinsic to all the orbits and in 1618, on May 15 according to his diary, Kepler saw it

Say you are 27 Earth years old and you want to imagine a planet where you would be just one year old right now (having lived the amount of life you have)---and would have ridden just one trip around the sun.

where would that planet be?

Kepler says to raise 27 to the 2/3 power----which gives 9.

Your planet would be 9 AU from the sun. It would be 9 times farther than the earth, assuming a similar orbit.

this number 2/3 is built into things----or, if you prefer, this number 3/2 that kepler called "sesqui"

for him the 3/2 power was the "sesquipotence" but written in Latin of course: the planet's period was the sesquipotentia of its average distance out from sun

for me, one of the most distinctive things about what is properly physics is that you make friends with hidden numbers which determine the deep structure of the universe

maybe you or someone else has a different take on what the essential thing about it is
 
  • #16
Hi Marcus,

Glad to see you're NOT shutting your mouth.

I hope to be able to add something more substantial to this in the next couple of days so don't mistake my lack of response for lack of interest. Just a little run off my feet at the moment.
 
  • #17
Numbers or the language of numbers, has not been a very meaningful language for me. That might say it all. In physics, I am the person who lives in the tropics speaking to the person who lives in the snow, about snow. Say I reach my understanding of 'what is' by a different language, that of art, or of music or of philosophical enquiry or of deep meditation and reflection and the development of a deeply attentive ability to see or listen, could these be considered valid constructions of meaningful truth for humanity?

If culture becomes shaped purely by the principles and axioms of a strictly scientific, empirical enquiry, are we in danger of creating exotic can-openers for a void of meaning? Whether a tale or not, is the idea of spirit more constructive to the human race than a mathematical principle which disables by its very parameters of meaning-bestowing via a very specific set of calculations. Man could find himself living on the moon or Mars but is man a worthy inhabitant or merely a clever form of bacteria?

Something pretentious, something foolish, childish, worshipful, something artful may be required in our natures to off-set the dangers of the new God, Science, in interaction between nature and human, being.
 
  • #18
Originally posted by Carla1

Something pretentious, something foolish, childish, worshipful, something artful may be required in our natures to off-set the dangers of the new God, Science, in interaction between nature and human, being.

Since you italicize to put special emphasis on art I am trying to think of what typifies art for me----laughter can be part of delighting in works of art, but I wouldn't describe any of my favorite works as foolish. Or childish or worshipful or pretentious.
probably not enough commonality of meaning for discussion to work.
would need more overlap in what we think of as "art-ful" or science-ful too I should imagine. Or "god-ly" too, for that matter. :smile:
There may be others at PF with whom you can reach a better understanding---everybody is free to define their own categories
 
  • #19
Originally posted by marcus
Since you italicize to put special emphasis on art I am trying to think of what typifies art for me----laughter can be part of delighting in works of art, but I wouldn't describe any of my favorite works as foolish. Or childish or worshipful or pretentious.
probably not enough commonality of meaning for discussion to work.
would need more overlap in what we think of as "art-ful" or science-ful too I should imagine. Or "god-ly" too, for that matter. :smile:
There may be others at PF with whom you can reach a better understanding---everybody is free to define their own categories


I am speaking of qualities of the human spirit using terms which are belittled rather than truly belittling. There need be no 'god-ly' enter into it yet for some, that will always remain a pre-requisite for meaning and what does it matter except when 'god-liness' becomes a slave-driver and a tyrant? Same with art, science or anything from which meaning is created.
 
  • #20
I have tried to get hold of a copy of Coming of age in the Milky Way but it seems to be out of print and I will have to order it in from overseas. Meanwhile, I bought a copy of The Anthropic Cosmological Principle by John Barrow and Frank Tippler which promises to contain an historical perspective of the development of science and cosmology. I also bought Chaos by James Gleick.

Perhaps you have heard of or read these works yourself. If so, feel free to offer a critique or an opinion. I look forward though, to having my perspective vitalised and deepened by these people.
 
  • #21
how terrible that Ferris book is out of print!
there must be some better way than having to spend lots of money ordering books!

Indeed incredibly enough I have exchanged a couple of snailmail letters with John Barrow but never read a book of his! I suspect
all that anthropic stuff is too hard to understand and fringe-y for my taste. But it may suit yours. I can offer no critique due to total ignorance!

meanwhile, we should learn how to use LaTex

there is a certain number 13 quintillion. One hears more and more about this number these days. Let us call it N, among ourselves, for convenience.

I went outdoors and it was in evidence in the cry of birds and the sound of the wind in the trees, and also it is present in supernovas.
A star which has finished with all fusion and is just quietly cooling down must be a certain mass if it is to enjoy a supernova explosion and this mass, expressed in natural mass units, is

(pi/4) N2

But also the air we breath has an average of 29 nucleons per molecule and so the average mass of a molecule of air is 29/N

this determines the temperature difference needed to cause wind to blow and it also determines the speed of sound

measured in natural units the square of the speed of sound in air at temperature T
must be (7/5)T/(29/N)= (7/5)NT/29

but the temperature here today is a chilly T = 2E-30
(about Fahrenheit 50 or Celsius 10, one needs a sweater outdoors)
so NT = 13E18 x 2E-30 = 26E-12
and NT/29 = (26/29)E-12
One multiplies that by (7/5) and takes square root and surprise it is the speed of sound.

John Barrow will doubtless be talking a lot about this number 13 quintillion that gets into so many things.

(if it were not right the chances for life would be less, but 13 quintillion is a very good size for it)

So when I see the wind sway the treebranches I think of supernovas---exploding stars---because the same number makes them.

There is another N-formula that gives the temperature drop with altitude needed to start convection currents, and thus wind, but I won't bother with it

What I really want to do is see how to write these formulas in LaTex

[tex]\displaystyle{\frac{7}{5}}\displaystyle{(\frac{T}{29/N})}[/tex]

wow, that is handsome is it not? that is the square of the speed of sound in air with molecular weight 29 and temperature T expressed in natural energy units. a textbook might say kT for temp expressed in energy units but in natural units there is only the energy scale for temp---no conventional one---so one can just say T.

[tex]\displaystyle{\frac{\pi}{4}}N^2}[/tex]

and that would be the mass involved in making supernovas, if it comes out right
 
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  • #22
John Barrow's book is probably rather hard to read but if it is a good book it will explain that our flesh is mostly made by stuff blown out into space by supernovas so the mass
that I just wrote is very important to us.

Most of the mass in your body is oxygen, carbon, and nitrogen


(there are a lot of hydrogen atoms too but they are little and don't account for much of your mass)

and the only reason that there was O, C, and N floating around in space able to condense onto planets as they formed is that there were supernovas here earlier

O, C, N are only formed in the cores of stars---at Bang time only light stuff like hydrogen and helium were made---but ordinary stars TRAP the O, C, and N that they form.

the only way there can be chemistry complex enough for life is if some stars explode and give us the O, C, N we need for interesting chemistry---supernovas give all the other elements heavier than that too but I'm focussing on my arm, your arm, what is the flesh made of--it came from one or more supernovas

but so did the stuff this computer is made of also---and so on.

So this number N which is 13 billion billion or 13 quintillion is
really important---for supernovas, for life, for sound, for wind, for no end of things.

so John Barrow ought to talk about it. it is one of the built in numbers intrinsic to the universe that apparently got set at the word go. and we depend on it (and several other basic proportions) being right.

he probably also talks about the number 1/137

my only quarrel is he and his friends seem to me to make the whole business a lot more complicated than it needs to be.
 
  • #23
Supernovas give us calcium too. So both flesh and bone.

I found a mistake in Book of Genesis chapter 1 verse 21
The original quite probably intended to say
"And God created great supernovas, and every living creature that moveth, and the waters brought forth abundantly, after their kind..."

but the scholars circa 1600 who were making the King James translation did not know from supernovas
so they translated it
"And God created great whales, and every living creature that moveth, and the waters brought forth abundantly, after their kind..."

whales is not bad
but it is obviously not true to the original
and just shows how scholars can mess up
due to incomplete information:wink:
 
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  • #24
That last post especially made me smile. Yeah...Barrow already leads me to understand that we are essentially made from the stuff of stars, which is rather cool (after it stops being so hot)in my opinion. Baked in the oven of a dieing sun. Something like that?

One day, I really sincerely do hope to be able to wrap my mind around the beauty of mathematics. When I see formulas, it makes little sense to me. When you explain physics to someone like me, it helps when you use pictorial references of language. In my head, it fits better somehow. The graphics-chip inside sets to work.

Last night, while I was on my way back from the shop, I saw a woman whizz by on a set of roller-blades. She called out to her partner behind her 'It's amazing how such small wheels can take you such a long way'. That statement, cried out in exuberance, I really wanted to tell you as soon as I heard it. Bringing things back to intuitive physics, I felt it was a potent, if unconscious, allegory to quantum physics. I wanted to know your thoughts.
 
  • #25
well since you ask, in this case I did not have any thoughts
only imagined sensations:
I can hear the roar of the rollerblades
and see the woman who is nice and athletic and obviously having
a good time

it is good to live within walking distance of a bookstore with an adequate selection of books---not everybody does and they may have to drive to get to a place where they can browse

the woman didnt inspire any thoughts about quantum physics, for me.
her point about the small wheels is right, it is amazing
that small solid wheels can accommodate a rough pavement
an enviable form of street-mobility.

I think the secret of how it works may be in the elasticity of the plastic wheels. the blade holding them may also be flexible and provide a kind of "suspension". I imagine that
the wheels are just soft enough to even out the bumps in the road
if they were hard and unyielding the rollerblades would not work so well.
but I am not sure about this. I never examined a pair or asked
 
  • #26
I would like to make a short comment (hopefully understandable despite of my mediocre english).

When I read the term ‘intuitive physics’ I must think on a mainly qualitative understanding of nature. I understand here 'qualitative' as opposed to 'quantitative', which is rather less intuitive. May be easy mathematical descriptions can provide an intuitive understanding, but intuition stops working somewhere where heavy math starts.

In the modern european culture, starting from the XVI century, there is a tendency towards quantitative description of nature leaving more and more the qualitative explanations.

A last example of battle between qualitative and quantitative pictures of nature is given by the contraposition between Goethe’s and Newton’s theories of light in the XVIII century.

In essence, the qualitative method considers subject and object as a whole and not sepparable. In the quantitative method analysis and objectivity are the main features. For the qualitative method analyzing means beaking a natural connection between subject and object given by the sensorial experience. This (sensorial experience) should be (accoding to the qualitative method) the ground of the physical understanding and the way to the truth (and not analysis and mathematical modelling as according to the quantitative method).

This shall be just an historical exposition. History of science proves that this qualitative method is definitely be wrong in some aspects, but this method was inequivocally beautiful. We won a lot with modern physics, but we must be aware that we lost an important link to reality.

Regards.
 
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  • #27
your english is fine, hellfire, completely understandable

this is Carla's thread----you and Carla may have large areas of agreement and, by discussing,each can help the other to think---and Carla can decide what is relevant

I don't know about Goethe's theory of light. I thought Newton did not have a good theory. Maybe Goethe was not right either.

I am a fan of Christian Huygens (1629-1695) and I think he had good ideas about light. He also conceived of an internal combustion PISTON AND CYLINDER ENGINE but his idea was to use gunpowder instead of petrol-and-air as we do today. His assistant Denis Papin ran off to England and helped invent the steam engine.
Also Huygens estimated the distance to the bright star Sirius. He did it by a strange method and got the wrong answer but it was the first attempt to measure the distance to a star, besides the sun. He tried to think of ways to fly---and even about life on other planets, he made clocks and telescopes.

Huygens had extremely good ideas about light. And so did Robert Hooke, and a medical doctor named Thomas Young 1773-1829.

I think you have to allow for human passions. Nothing is "lost" by discovering mathematical models if they arise from a love of nature and a strong desire to learn her secrets. If the models are not simple and beautiful enough they should eventually be replaced by better ones. A clumsy model is only a temporary expedient.

It is also possible to write bad poetry. Neither mathematics or poetry is perfect or works all the time. How did Goethe explain light? Perhaps he was right!

Feynmann has argued against the viewpoint that physical understanding (of how atoms work) diminishes enjoyment of nature. Feynman maintained that he just had MORE ways to enjoy a sunset because he could see the red clouds as well as a painter (and indeed he was a painter sometimes) and ALSO he could see in the sunset the beautiful mechanism by which the blue light is scattered sideways as the light goes thru the atmosphere so that mostly only the red light reaches us. Also when he was at the beach, asserted Feynmann, he just had MORE to enjoy because he could see and hear the waves and enjoy the sand between his toes like anyone else but also he could appreciate other facets and dimensions of it

...In the modern european culture, starting from the XVI century, there is a tendency towards quantitative description of nature leaving more and more the qualitative explanations.

A last example of battle between qualitative and quantitative pictures of nature ...

I don't think there has been a "battle"...
One should have both kinds of understanding and descriptions, as much and as clear as possible.
If modern Europeans are leaving qualitative description of life they are making a big mistake.
But I don't think they are...when they go to the beach they probably not thinking about wave equations and atmosphere dynamics and how the sun makes light shining on the water and how the water molecules reflect it etc. The modern Europeans I know do not have a "tendency towards quantitative description" of the beach. Though it wouldn't hurt them if some did, or so I think

---------------
there are many depressing tendencies in the world and some very valuable things are being lost,
but the gradual improvement in mathematical models (and ability to display the results graphically) is not one of the depressing things, more on the other side---something hopeful

Carla, on the other hand might have a totally different opinion! So maybe you will get some very differnt responses :smile:
 
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  • #28
Well, marcus, you may be right that there was no battle at all, but I believe there was sometimes a battle, or at least passionated discussions regarding the role of quantitative methods for the understanding of nature. I think the origin of these can be traced to Plato and Aristotle, with the different roles of sensorial experience in knowledge. Anyway, I am not an expert in history of science and I cannot be more profound here.

On the other hand may be you misunderstood me. I was not talking about life, but about science. Of course nobody thinks about mathematical models when swiming in the sea or being in the beach, but, note: no scientific theory relies today on physical feelings, or on anykind of role of the subject when explaining something.

For example: as you probably know, the ancient greeks postulated the world to be made of earth, fire, water and air. We may laugh about that from our quantitative and analitic way of thinking, but it is subtle: it depends only on which point of the distance between object and subject you are focusing. Their focus was near the subject and they thought that the different categories of sensorial feeling shoud determinate, or at least give clear hints about the nature of the objects. The next step is obvious: just look in yourself and find out which categories of sensorial feeling you may experience and then try to extrapolate to reality.

I am confident that something like this is definitely lost in the occidental culture, means a different kind of relation between subject and knowledge, a different weighting. Whether this can be regarded to be more intuitive than modern physics is another question. In my oppinion it may, it depends what we understand under the term intuition.
 
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  • #29
now I see better what you mean, hellfire, and if I understand you
correctly I think you have a good point.
just talking about SCIENCE it seems to me that
there has been a real shift towards mathematical description and
modeling

and not merely a shift towards emphasizing quantities
but a shift towards more sophisticated algebra and even subtle geometry

Kepler circa 1618 is often for me the test if something is true.
For over 15 centuries before him they had the Ptolemaic system which had plenty of quantities! It had all the radiuses of all the spheres! It had all the time periods of all the cycles! So if one just focuses on SCIENCE as you suggest you have them using lots and lots of QUANTITIES for 15 centuries and making very good quantitative predictions.

Kepler made a couple of subtle changes. It was not to be circles anymore, instead it was to be ellipses. You could even say it was a QUALITATIVE change that he made, to go from circles to ellipes and to get rid of all the extra spheres.

[the Copernicus model goes back to 250 BC and Aristarchus, and it does not actually work because it uses circles, so Mars will not fit.
the really new thing was not Copernicus but Kepler, and it was a qualitative change]

Another change was Kepler discovered that the planet's distance from sun was not merely straigt-line proportional to its year-period. He found a relation that is SUBTLY DIFFERENT from a straight line. He discovered the distance from sun is 2/3 power of the period.

Both these moves are in the direction of more sophisticated math----circle changing to ellipse---linear, square, cube algebra moving to more subtle 2/3 power algebra.

One of the main goals in improving a scientific model is to get rid of numbers.
One sees the same progress in 20th century particle physics and in the replacement of Ptolemaic model. In the Ptolemaic model one had to specify more than twice as many number. Radii for all the spheres AND time periods for them to turn. Starting in 1618 more than half those numbers went away because you only had to list the periods of the planets and they would imply the distances from sun.

The smarter the model, the fewer numbers it needs to have input before it can start to run and make predictions

(Well there are other criteria of elegance too, but that is one of the main ones.)

So I would not call the trend, since 1618, one from qualities to quantities----I would see it as one from verbal explanation to mathematical modeling.
I see mathematical models as highly qualitative and capable of subtlety. there is a rich diversity ways to model things
and even seemingly little differences, like between circle and ellipse
can make a change

or between the 1/2 power (the square root) and the 2/3 power

before 1618 one had verbal classifications of materials to try to explain why some would burn, why some would melt or vaporize, and others would not, alchemy.
eventually there is an atomic model which roughly predicts which reactions happen readily and which combinations are possible, chemistry.
the chemical model uses numbers----numbers of electrons in the outer shell, for the most part, and associated valences.
there is less ad hoc stuff to remember and more that is predicted just by the atomic number, or the electron shell.
Carbon is Mr. 6, Nitrogen is Mr. 7, Oxygen is Mrs. 8. You almost can forget their antique names and just call them 6,7, and 8. And then these number-names will tell you things about how they behave.

Yes, I see a trend away from verbal classification and towards mathematical modeling----and also a process of qualitative refinement within the mathematical models. a process models of getting more varied and predictive and less clunky.

maybe this is so obvious to people it doesn't need to be said!
I will post it and erase later if it seems superfluous.
 
  • #30
Just to let you know, I've started a new job. It's taxing the living daylights out of my time and energy so hard to give valuable input to this thread at the moment. Might have to resign myself to weekends for the moment. A pity, at a brief glance, both of you have added something from two unique and equally valid perspectives which makes for interesting reading and the difference in culturual background is a plus in my opinion.
 

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