How do we know that the "laws" of physics are really laws, i.e. true everywhere?

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Offline rainwildman

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something that has aways puzzled me, so maybe someone can help....
It is of fundamental importance to the theories of physics that the laws if physics are the same everywhere in the universe.  Also, that space is the same everywhere.  How can we possibly know this? 

If someone can explain to me how we can know this, then fine, but it seems to me almost absurd to say that we KNOW that space and the laws of physics are just the same at the other end of the universe as they are here, yet, if we cannot say that, then none of the grand theories of how the universe was made and stars evolve and so on can be true!!!

oh dear!  Anyone help?
« Last Edit: 15/04/2008 09:12:57 by chris »

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another_someone

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Laws are whatever you make laws to be.  A law is merely a rule you put in a model.  You can choose which laws work for the particular model you are trying to create.  If the laws you are seeking are something that are universal, then you try to select laws that are universal.

This does not mean that you cannot see different behaviour in different parts of the universe (just as you can see different behaviour in liquid water, ice, and steam; but you create laws that allow you to view these different behaviours as simply different manifestations of the same laws).

Ofcourse, we cannot actually know what happens at the other end of the universe, so we cannot say what behaviours exist there, and so what our laws must explain.  What we can say is what it is we see happening at the far end of the universe, and say that the laws we develop must somehow explain these observations.  If we ever get to visit the far reaches of the universe (a scenario that is at present somewhat unlikely) then it may well be that we will be in for some surprises, and that these surprises will force us to have to change what we consider to be fundamental laws; but that is the nature of science, that as we develop the capability to make new observations, we either reaffirm out existing laws, or force a situation where they must be reviewed.  Science is never definitive, it is always merely state of the art, and tomorrow it may be different.

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Offline Soul Surfer

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It is not totally fundamental that the laws do not change at all. In fact many possibilities exist that fundamental constants like for example the speed of light may change in very extreme conditions.  It is however fundamental that the constants change slowly and evenly with time and/or distance.

There is very good evidence that the main constants and laws do not change over vast distances of time and space as far as the most remote visible objects and even as far as the origin of the cosmic microwave when the whole universe was as hot and dense as the surface of a star and even back to the first few microseconds when the basic elements were being formed when the temperature and density was like the core of a star.
« Last Edit: 27/03/2008 09:28:03 by Soul Surfer »
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Offline rainwildman

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I,m afraid the talk of 'models' does not allay my fears. In fact, quite the opposite, because it makes physics sound like a game of 'fit the image to the stars', you know, looking at the stars and seeing pictures in them, and, really, you can see any picture you like, and especially if you select which stars to include!

It seems to me that the world we live in is incredibly complex, and you could probably make any number of different models to fit it, especially if you select the bits you choose to include.  And now I start thinking to myself (and I should say here that I happen to have heard that the Einstein model of the universe was not the only one on offer at the time, but the others have been forgotten because, well, to be blunt, Einstein had the right friends!)... so, to get back to what I am thinking to myself, is the science that we have today the only model that we could be using?  If there are others, why are we using the one we are using?  Is it because say, Newton or Faraday or Maxwell, had enough clout that they could have their theories oust all the competition?  And then, if we are saying that it is a matter of 'whose' theory it was, rather than which theory might be best, then what are the consequences?  Are we in fact left with a model of the universe which is very inferior to what we might have had if truth had mattered more than vested interest?

The more I go down this road the more uneasy I become.....

Again I have to say... help!!!

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lyner

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Quantum Physics predicts, successfully, quite a lot about the spectra of radiation from atoms and our local observations confirm it. When you observe the light from very distant objects you see the same patterns - just red shifted. That is quite strong evidence that the atoms producing this light are behaving (pretty much) the same as the atoms here. That implies that the constants of Physics are much the same at remote places in the Universe.
Also, you have to start somewhere so . . . 
Quote
you could probably make any number of different models to fit it, especially if you select the bits you choose to include.
There won't be that many models which actually FIT all the observed facts. You can only really expect to extend the present model. This may annoy you but the more you know, the more reasonable the existing models (as far as they go)  seem. 
If you treat Science as magic, you can allow just about anything in the way of a model. If you accept that it must be verifiable, when possible, this limits the number of possible models somewhat.
I would say that the present model(s) are not bad, as far as they go. Other models don't go as far.
« Last Edit: 27/03/2008 21:43:32 by sophiecentaur »

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another_someone

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I,m afraid the talk of 'models' does not allay my fears. In fact, quite the opposite, because it makes physics sound like a game of 'fit the image to the stars', you know, looking at the stars and seeing pictures in them, and, really, you can see any picture you like, and especially if you select which stars to include!

It seems to me that the world we live in is incredibly complex, and you could probably make any number of different models to fit it, especially if you select the bits you choose to include.  And now I start thinking to myself (and I should say here that I happen to have heard that the Einstein model of the universe was not the only one on offer at the time, but the others have been forgotten because, well, to be blunt, Einstein had the right friends!)... so, to get back to what I am thinking to myself, is the science that we have today the only model that we could be using?  If there are others, why are we using the one we are using?  Is it because say, Newton or Faraday or Maxwell, had enough clout that they could have their theories oust all the competition?  And then, if we are saying that it is a matter of 'whose' theory it was, rather than which theory might be best, then what are the consequences?  Are we in fact left with a model of the universe which is very inferior to what we might have had if truth had mattered more than vested interest?

The more I go down this road the more uneasy I become.....

Again I have to say... help!!!

Very possibly more that one model would fit the observations, but far more would not.

The reason why Einstein's model succeeded had nothing to do with his friends (in fact, most of the ideas were not his - look at the background to Lorenz, Poincaré, FitzGerald, and others), but he put the ideas together in their simplest form, and so created a simple and functional model that explained far more of what was observable with greater simplicity of form than all the other alternatives.

One of the things one should note is the ease with which extremely complex systems can be formed with extremely simple rules, and often the greater the complexity the simpler the underlying rules (look at the construction of cellular automata).

Yes, it is very possible that a totally different set of laws could be constructed to explain the observations available, but given the enormous amount of work over the centuries that have gone into creating the existing set of laws, and showing how they can be used to explain all we see, and it would probably take an almost equal number of centuries to prove any alternative set of laws to be as efficient in describing all we see.

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Offline Kryptid

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If I'm not mistaken, the spectra of elements in other parts of the Universe have been recorded from their light and are the same as the spectra of those same elements on Earth, right (except that they are modified slightly by redshift or blueshift of the light)?

If the spectra of elements is the same there as it is here, then the physics that governs atoms much be the same as well. For example, the EM strength must be the same, as must the quantum numbers that determine electronic structure. The mass of the electron must be the same as well.

Outside of the Hubble Horizon, though, who knows?

edit: sophiecentaur beat me to it.
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another_someone

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If I'm not mistaken, the spectra of elements in other parts of the Universe have been recorded from their light and are the same as the spectra of those same elements on Earth, right (except that they are modified slightly by redshift or blueshift of the light)?

If the spectra of elements is the same there as it is here, then the physics that governs atoms much be the same as well. For example, the EM strength must be the same, as must the quantum numbers that determine electronic structure. The mass of the electron must be the same as well.

If one is going to play devils advocate on this, I am not sure it does mean that EM strengths are the same.  As you say, we have red shifts (occasional blue shifts, but at great distance, I believe they are all red shifts), but what we know is that the relative positions of the spectral lines match up with spectral lines observed on Earth, while their overall position in the spectrum has shifted.  Thus we can surmise that overall structures that cause the emissions are similar to what we have here, but can we preclude that the structures have been scaled in some way, while retaining their same relative energies?

It is not the most likely scenario, but the question is, can we prove it to be a false scenario?

As you say, this only works as far as we can see stars, but beyond the point where we see stars we really cannot say very much.

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Offline DoctorBeaver

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Wouldn't you love to know, though!
Fledgling science site at http://www.sciencefile.org/SF/content/view/54/98/ needs members and original articles. If you can help, please join.

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lyner

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Wouldn't you love to know, though!
Are you suggesting that it is necessarily 'knowable' and 'understandable'?

I have enough probs with the story so far.

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lyner

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Quote
As you say, this only works as far as we can see stars, but beyond the point where we see stars we really cannot say very much.
you can imply quite a lot, though. If things were, in fact, very different beyond our vision then an observer out there would see different pictures in different directions.
Likely? |It would be a real coincidence; hence the Cosmological principle.

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Offline DoctorBeaver

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Wouldn't you love to know, though!
Are you suggesting that it is necessarily 'knowable' and 'understandable'?


No, I'm not suggesting that. I would just love to know what's there.
Fledgling science site at http://www.sciencefile.org/SF/content/view/54/98/ needs members and original articles. If you can help, please join.

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Offline Soul Surfer

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Rainwildman.  All your experience consists of models of reality created by your own brain.  If you are afraid of models (simplified systems that mimic parts of "reality" accurately within defined limits)  you are afraid of your own mind as well as science.

Just like everyone looking at growing grass in sunlight and agreeing that they will call the colour green it is quite possible for you to disagree and call it qwert but you will be in a minority of one.  No scientific theory is ever the work of one person.  One person may originate the idea but many others will try to pick holes in it and eventually agree that the idea has some merit and eventually progress will be made.  That is what peer review is all about.  I agree that ideas can often be missed rejected and lost and then discovered again.  Science is full of examples of people who have had good ideas but failed to explain them properly and they were howled to derision  it is the proving and explaining process that is really important not just the idea.

One of the problems with many of the people who present interesting ideas to the new theories section is that they think that because they have had an interesting idea that might fit one bit of reality better than the current picture  everyone should rush to agree with them.   Some fools do but that is not science.

One of the really big problems with fundamental physics at the moment is that there are literally billions of good ideas but no way of proving which is best.  we are a long way from the last significant breakthrough and  need to find a genius who will understand where things are and come up with a new approach to produce good and testable solution.
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another_someone

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Quote
As you say, this only works as far as we can see stars, but beyond the point where we see stars we really cannot say very much.
you can imply quite a lot, though. If things were, in fact, very different beyond our vision then an observer out there would see different pictures in different directions.
Likely? |It would be a real coincidence; hence the Cosmological principle.

One thing you have to bear in mind when you look to the edges of the see-able universe is that you are not only looking into a spacial distance, but into a temporal distance, and in that sense we are in a unique position, in that our own position is the only position which we can view in the present rather than the historic past.

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Offline techmind

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It is of fundamental importance to the theories of physics that the laws if physics are the same everywhere in the universe.  Also, that space is the same everywhere.  How can we possibly know this? 

In the absence of any evidence to the contrary, we postulate that this is true. It has served us well so far.

As others have mentioned, the evidence of (albeit red-shifted) emission- and absorption-spectra in the light from distant stars is a good indication that physical constants are pretty much the same in the furthest places we can see. The red-shift itself fits reasonably into our existing understanding too.

Physics aims to understand all the effects we can observe. Present theories in the main do a good job of describing what we can see. If at some stage in the future it was discovered that some physics was different someplace, then a new theory would be developed... which (mathematically) would tend back to the existing theory (i.e. predict the same observable results) under the condtions/space that the existing theory is valid.
This is what happens with Einstein's relativity - it describes new phenomena which happen at very high speeds/energies... but gives the same results as basic Newtonian motion at everyday slow speeds and energies.


Physics proceeds by getting to the heart of any "problem" or physical "situation". It seeks to find the simplest explanation for the observable facts. You do the experiment, and find that the result depends on A, B, and C. You manage to explicitly test that the result is completely independent (insensitive to) V, W, X, Y, and Z. Furthermore, you observe some evidence of the same phenomena -perhaps some situation where you can't measure or control a host of other potential parameters R,S,T,U - and the observable outcome in this case is still as predicted on the basis of A,B, and C alone. This gives you confidence that your theory is useful (even if there is a small chance that there's some as-yet undiscovered exceptions to the theory).

If we stick with the idea of "simplest possible" explanations, then even if an alternative "verbal"/"descriptive" theory were proposed in future, it's predictions would have to be consistent with the universe with which we are already familiar, and the maths resulting from "alternative" theories would similarly boil down to the existing maths (i.e. by rearranging and substituting into the equations - mere algebraic manipulations).
To avoid having to rewrite the textbooks every few years, and confusing everyone, "new" theories only become accepted if they have a significant advantage over existing theories (e.g. wider validity, demonstrably better fit to *all* existing data, or vastly more logical/easier to comprehend). Sure, in the rel world there can be some politics too, but this is the principle.

Both particle physics and early-universe/big-bang "physics" are mostly observed only very indirectly, under conditions which we cannot easily control or adjust (or re-play/reproduce). It could be argued that some of the theories in these fields are charging ahead of what can be really justified by observation. Such theories are clearly much more "at risk" of being revised than in most other areas of physics. You might say that in some sense such areas are as much philosophy as physics!
« Last Edit: 28/03/2008 14:39:25 by techmind »
"It has been said that the primary function of schools is to impart enough facts to make children stop asking questions. Some, with whom the schools do not succeed, become scientists." - Schmidt-Nielsen "Memoirs of a curious scientist"

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Offline rainwildman

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OK, someone has been kind enough to play devil's advocate, and the conclusion is that we cannot be sure about physical theories.  Then someone else agreed, and then justified our going with the current theories on the basis of the difficulties of looking for and establishing others. 

Two things about that: in the first place, I thought science was about TRUTH, and if it is, then difficulty is neither here nor there.  This thing about difficulty and cost in time and effort is putting expediency before TRUTH, and surely that cannot be right or healthy?  And talking of health, physics is surely just the base science upon which most others build, and if that is so, then if physics is uncertain, then so too must be all the others, and if that is true, then it applies to medical sciences, and that has my hair standing on end, because I need to be able to trust the medical professionals!


Soul Surfer says my brain is doing the same thing as scientists ... I disagree.  If I fall down, my brain concludes that there is something that makes me go downwards with a bump, as it were, but it would not go off and make work out that it was an inverse square law, and then use that to make predictions about projectiles and planets in orbit and so on.  And if at some later time I was to lose my footing and NOT fall down, it would take that on board and modify my view of the world and my bahaviour accordingly .... in fact, something is just occuring to me as i write, and it is to do with competition:  it seems to me that my brain id fundamentally different in that is ACCUMULATES from experience, takes EVERYTHING on board, which is different from science, where one theory has to COMPETE with another.

And then I am thinking, perhaps the problem is not which theory might be correct, and that we might not have the best one, perhaps the problem is that we only have one theory, whereas the truth is that they are ALL correct, and the prblem might be that we need to BROADEN our way of looking at the world.  Rather than thinking in terms of one theory being correct and the others wrong, we should be thinking in terms of how to reconcile them all.

Well, this is certainly getting me thinking!

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another_someone

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Two things about that: in the first place, I thought science was about TRUTH, and if it is, then difficulty is neither here nor there.  This thing about difficulty and cost in time and effort is putting expediency before TRUTH, and surely that cannot be right or healthy?

Absolute truth is something that exists in the realms of abstract logic only.

You are looking for an idealised situation that does not, and in reality, cannot, exist.

Is this healthy?  In the real world, absolute health does not exist - which is why none of us are immortal.  You do the best you can with what you have, and accept that what you have has its limitations.

And talking of health, physics is surely just the base science upon which most others build, and if that is so, then if physics is uncertain, then so too must be all the others, and if that is true, then it applies to medical sciences, and that has my hair standing on end, because I need to be able to trust the medical professionals!

Simple answer - thalidomide (and that is just the tip of the iceberg).  Scientists, medical practitioners, et. al., are merely human beings, and none should be treated as gods, for they can never be that.


Soul Surfer says my brain is doing the same thing as scientists ... I disagree.  If I fall down, my brain concludes that there is something that makes me go downwards with a bump, as it were, but it would not go off and make work out that it was an inverse square law, and then use that to make predictions about projectiles and planets in orbit and so on.

If someone throws a ball at you, your brain does a fairly good job of making predictions about where the ball is going to travel, and if you want to catch the ball, where you should place yourself to intercept the ball.  In making these predictions, you brain is making a model of the flight of the ball, and is doing whatever calculations it needs to in order to forcast the position of the ball in a few milliseconds time.

It is true that the average caveman did not have the formal tools to make an inverse square law (how would he have written down the notion of what a mathematical square, let alone and inverse square was); but he would have had a good enough intuitive knowledge of the inverse square law to be able to make fairly good calculations of ballistic flight of many objects.  He would also have known enough to know that dropping something from twice the height will give you more than twice the energy.

in fact, something is just occuring to me as i write, and it is to do with competition:  it seems to me that my brain id fundamentally different in that is ACCUMULATES from experience, takes EVERYTHING on board, which is different from science, where one theory has to COMPETE with another.

No difference at all.

The whole point about science is that it too must take everything on board - but you are confusing experiment with theory.  Your experience is equivalent to scientific experiment - and science cannot pick and choose to ignore one experimental result but accept another - if an experiment is repeatable, then the theories chosen must take account of it.  In the same way, an isolated experience you can choose to ignore, but if an experience is repeatable, then you must learn from that experience.

Scientific theory is about prediction.  When you have learnt from experience, then you will start to make predictions about the future; but just like scientific theories, you will have competing means of predicting the future, but you have to choose one that works best.

Going back to the question of ballistics - experimental science will have you throw the ball several times and observe where it will land, while theoretical science will have you calculate where the ball will land while it is still in flight.  You brain and science are doing exactly the same job.  When you want to catch a ball, you will initially have several competing theories about where the ball will land, and will often get it wrong, until you finally get to one theory that always puts you in the right place to catch the ball every time.

Well, this is certainly getting me thinking!

That itself is good.
« Last Edit: 28/03/2008 15:36:54 by another_someone »

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Offline rainwildman

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I'm still thinking, and trying hard to understand.  I am an artist(words and images) by profession, but i took science to a higher level than most artists.  The trouble was that I always felt like a trained parrot, that is to say, that i was just learning stuff by rote and then regurgitating without understanding anything.  So now I am revisiting and trying to put that right.

So, right now I'm battling with a couple of things that were touched on above;
first, what is made of observations of light from distant stars and galaxies (as an artist I certainly love the pictures that come from this!)
If I get this correctly, scientists look at light coming from sources in the sky, and they, as it were, draw a picture of what they see, and then they look at what they have here on earth, and they say that the light from the stars looks just the same as the light from atoms or whatever, that we have on earth, and therefore they must be the same thing.  Well, that is too simplistic, and the can't be right.

I have a friend who is working on a book about, among other things, Freud and Jung, and she has been telling me about some of the methods Freud used to come to his conclusions about what dreams meant.  So, for example, in one dream a snake approaches the dreamer, grows bigger, bites the dreamer, and then shrivells.  Well, says Freud, this is a sex dream, because something that burgeons and then shrivells must be a phallus!  Of course that is nonsense.  The flowers in my garden burgeon and then wither; a balloon being blown up burgeons and then withers when the air is released; a little boy boasting swells with pride and then can be withered by a withering glance ... and so on and so on. 

So, just because two things look alike, one can conclude nothing.  So what is the difference between what scientists are doing with the things they see in the night sky and what Freud (and numerous pseudo-scientist)were doing with the things they were looking at?


Another point, which is not really pertinent, I think, to the understanding of how science works, but has been mentioned above, is the PEER REVIEW SYSTEM.  To me, that is iniquitous, but is politics, not science.  Peer review is the church fathers deciding what is and is not acceptable.  If Einstein(honest its nothing personal, but if you become famous then you have to take the flack) got onto a peer review board, then he could make sure that it was his name that got remembered, and his theories that won out over the competition.

What peer review makes me think of is another famous name: Plato.  One of Plato's major works was THE REPUBLIC.  Now, in that work of philosophy, Plato draws a picture for us of what he has 'reasoned' would be the ideal and best society, and guess who's in charge of this utopia ... that's right, philosophers!  so don't tell me Plato was a philosopher, interested in truth and capable of detached reasoning.  He was not.  he was a poltician making a case for why he and his party should be in charge!  Now I have a lot of trouble with peer review on the same basis.  It smacks of the rule of politics at the expense of detached reasoning and loyalty to personal interest over loyalty to truth.

However, as I said, it is the thing about spectra that really bothers me.

Maybe someone can explain.

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Offline Soul Surfer

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Experiments on earth can determine the mass and electrical charge on a proton and on an electron. putting one proton and one electron together creates a hydrogen atom. The physical laws associated with this combination predict that when excited, hydrogen atoms will radiate very specific sets of frequencies in the optical infra red and ultra violet and radio bands.  Experiments in the laboratory also show that these spectrum lines are accurate.  Similar sets of spectrum lines can be seen in the sun other stars and distant galaxies not just single lines but whole sets with precise separations.  This enables the accurate determination of the relative velocity of the source and the observer.  All other elements and compounds have different sets of spectrum lines predicted, measured and observed in remote objects.  All the velocities measured on the same object are similar.  This gives very accurate information about the composition temperature pressure and radial velocity (including changes with time) of millions of objects this in turn produces and confirms models of stellar evolution the structure if multiple star systems and the structure of galaxies.  Gravitational theory even allows masses of multiple stars to be messured.  All this knowledge is consistent and has been measured by thousands of observers over hundreds of years.

Our knowledge of nuclear physics allows precise models of the origination and evolution of stars to be generated and confirmed by the observation of star clusters which are likely to have originated at a similar time this varies from clusters only a million years old to ones almost as old as the universe.

This list of observations cross linked by many confirming observations gives rise to the information given in popular science books.  it id not the ramblings of one individual but a whole network.
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lyner

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Peer review may seem problematical if you regard Science as a creative art form. But Science doesn't attempt to be one.
Yes, it can suffer from subjectiveness and personal interest but the fictional scenario of which we frequently read in these forums - famous scientist rejects  brilliant idea from young upstart - is very much in the minority. Once a new idea is out, if it really is valid then it will find a way to get accepted. If the feelings of some bright spark are hurt a little then he / she will get over it. If a barmy idea was accepted without a struggle, what damage could be done to Science?
How else and with what other system can we actually make progress and avoid a world of Scientific blind alleys?
It strikes me that people are getting a vicarious displeasure out of these scenarios rather than appreciating that Science must be conservative in order to make any real progress.

Think how the MMR fiasco caused so much potential suffering because the (science-ignorant) media took up the idea of a errant medic and didn't allow the  Science establishment to work properly.

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Offline techmind

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first, what is made of observations of light from distant stars and galaxies (as an artist I certainly love the pictures that come from this!)
If I get this correctly, scientists look at light coming from sources in the sky, and they, as it were, draw a picture of what they see, and then they look at what they have here on earth, and they say that the light from the stars looks just the same as the light from atoms or whatever, that we have on earth, and therefore they must be the same thing.  Well, that is too simplistic, and the can't be right.

Human-perceiveable colours can be described using just two numbers, and located at a position (x,y) on a Chromaticity diagram (this ignores brightness and just considers 'hue').
 http://www.techmind.org/colour/   (see a chromaticity diagram about half-way down my page here)
If two things merely "look" the same colour to the naked eye, then that certainly doesn't tell you that they have any common chemical connection or whatever. Sometimes two things that look the same colour under one light, will look a slightly different colours under a different sort of light.

So, just because two things look alike, one can conclude nothing.  So what is the difference between what scientists are doing with the things they see in the night sky and what Freud (and numerous pseudo-scientist)were doing with the things they were looking at?


But if we use a high-resolution spectrometer to measure light, we can measure potentially hundreds or thousands of spectral lines within the visible spectrum and beyond, and relative strengths of them. It's like a "fingerprint" (or "DNA") of what gasses were present where the light was created. Because you've essentially got a large number of variables (with millions of potential combinations) but they ALL MATCH to something we can recreate on earth, you can be pretty confident that the results are telling you something meaningful.

For example of the "fingerprint" of light from our sun, see: http://chinook.kpc.alaska.edu/~ifafv/lecture/fraunhofer.htm


In the case of spectra of starlight, the phrase "looking alike" does not do justice to the degree of detail and precision of match we can observe with scientific instrumentation.
« Last Edit: 30/03/2008 00:25:40 by techmind »
"It has been said that the primary function of schools is to impart enough facts to make children stop asking questions. Some, with whom the schools do not succeed, become scientists." - Schmidt-Nielsen "Memoirs of a curious scientist"

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Offline Kryptid

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Well, there's also Occam's Razor. We shouldn't assume that the laws of physics must differ in one part of the Universe from that of another part until we have reason to believe that is the case. It could be said that the innermost cubic centimeter of the Moon's core experiences different laws of physics than the rest of the Moon. We haven't directly observed this region, so this claim could be true. However, we have no reason to think this is the case. Hence, we assume that this region obeys physics as we know it.

I'm wondering, do you have a reason to believe that the space far away from us is different from that space immediately around us?
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lyner

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Offline rainwildman

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Thank you soul surfer for that very lucid description of how spectrum lines work.

I'm sorry, techmind, but what you seem to be saying is that it is not just that one thing looks like another, but that it looks VERY like another, and that makes no difference that I can see.

And, Supercryptid, that is a very interesting question, and it has had me thinking, and I think I have to say, yes, I do have reason to think that things at the other end of the universe are different from here!  This is quite hard to explain, but in a word: intuition.  What do I mean by that?  I mean a feeling that comes from my experience of the world.  I have travelled a lot, done a lot of things, etc etc, and all my acrued experience leads me to have a sense that the world is not as simple as that.  I would say, that all me experience leads me to have a feeling that things MUST be different billions and billions of miles away across all this black space.  It is simply counter-intuitive.

I think this leads to some interesting thoughts.... I mean, the more I think about it the more I think how very counter-intuitive science is at almost every turn.

Lets go right back to the beginning of science!  I have usually heard it said, (I watch programmes like COSMOS by Carl Sagan and the like) that the roots of modern science go back to the ancient Greeks.

As an artist, i am well acquainted with the ancient Greeks.  They had a preoccupation with 'reality'.  It is often claimed that they took art forwards by discarding the kind of thing the Egyptians were doing .... representing people or gods as having heads of animals and so on .... and concentrating on creating images that 'looked' real.  Well, actually, what the Greeks were doing was throwing out INSIGHT in favour of surface look-a-like.  When the older cultures represented people and gods as having animal heads and so on, they were using METAPHOR to reveal insights into how those gods and people BEHAVED.  So, when we talk of someone as 'bullish', or as predatory, we are saying things about how they think and behave, and if we represent these people as having the appropriate animal parts, we are communicating our insights about their true natures.  That insight is what the Greeks threw out!  So they left us with a much shallower art, that concerns itself only with what is on the surface.  I wonder, did they do the same with science?

In the days of the ancient Egyptians, people dreamed at night, and then they got up in the day, and it seemed to them that there was little difference between what they experienced in their dreams and what they experienced when awake.  So it was commomplace for them to think that 'life is just a dream', or, in our modern terms, a virtual reality.  That is to say, an ancient Egyptian would have said it was INTUITIVELY OBVIOUS that life is a dream.

What I am getting at is this: that somehow, starting with the ancient Greeks it seems to me we have been persuaded to discard what is intuitively obvious in favour of .... what? 

If you say something to someone often enough (and coca cola advertisers among others are very well aware of this effect) they will come to accept it.  So, has science brain-washed us into accepting things that are not at all reasonable? 

So, you ask me, have I a reason to think that things might be different at the other side of the universe?  I say, intuitively, yes. 

On the other hand, I could turn round and say, do you have any reason to suppose things are the same at the other end of the universe?  And what?  You put the onus on me to justify what I am saying and say that if you do not KNOW things are different, then you have to think they are the same?  No to that.

And that brings up something else!  What about the simplest answer of all, and the REALLY correct one: I DO NOT KNOW.  Is it not better to say 'I do not know' that to grab hold of some idea that might be totally wrong?  I mean, there could be very serious repercussions in deciding that a bad idea is better than no idea!  It is like building your house on sand, or faulty foundations ... in the end you will pay the price!

I do hope scientists are as robust as they seem.  I am poking and proding, but then, they do actually profess to hold a defensible position, and to welcome scrutiny!

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lyner

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Did Carl Sagan ever subscribe to whacky, fringe Science ideas? He may have been a bit of a showman but he totally subscribed to all the basics.
Science is not at all 'simple' but it attempts at being the most simple solution to explain what we see. It's called 'reductionist'. If you want to start out on a divergent path you will never get anywhere.
You need to read around a bit. You will not find many instances where Newton's laws are contradicted in everyday experience; few quantum Physicists or state of the art 'Theory of Everything' researchers feel it necessary to rubbish established Science; they just need to extend it.
When you know enough to feel you have an understanding of what they are all saying you will be in a position to have a really valid objection to the basics - if you still feel the need to.
To imagine that you can say the Science has got it wrong is a bit like saying the French have got their language all wrong and they should be using different vocabulary and grammar. The only people entitled to have a valid view about that are fluent French speakers with a significant knowledge of French literature.
I haven't found many websites where that idea is promoted.
If you want Science to be 'intuitive' then you will find a lot of problems designing fast cars, computers and pharmaceutical drugs. Intuition may help you   make the occasional forward leap but it has to be followed, pretty quickly, with some serious hard graft and measurements.
« Last Edit: 30/03/2008 22:26:44 by sophiecentaur »

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another_someone

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Lets go right back to the beginning of science!  I have usually heard it said, (I watch programmes like COSMOS by Carl Sagan and the like) that the roots of modern science go back to the ancient Greeks.

As an artist, i am well acquainted with the ancient Greeks.  They had a preoccupation with 'reality'.  It is often claimed that they took art forwards by discarding the kind of thing the Egyptians were doing .... representing people or gods as having heads of animals and so on .... and concentrating on creating images that 'looked' real.  Well, actually, what the Greeks were doing was throwing out INSIGHT in favour of surface look-a-like.  When the older cultures represented people and gods as having animal heads and so on, they were using METAPHOR to reveal insights into how those gods and people BEHAVED.  So, when we talk of someone as 'bullish', or as predatory, we are saying things about how they think and behave, and if we represent these people as having the appropriate animal parts, we are communicating our insights about their true natures.  That insight is what the Greeks threw out!  So they left us with a much shallower art, that concerns itself only with what is on the surface.  I wonder, did they do the same with science?

Not sure that one can say the Greeks started science - I suspect the roots of science go back further than that, but the Greeks were the one's to bring us ideas that were around from various sources before then.

In ancient times, the Greeks had a major empire, and so were in a position to bring ideas together from lost of different sources.  Most of the 'Greeks' we know of as being important were not living in Greece, but in the various colonies the Greeks had.

As an analogy, we regard the modern system of numbers is regarded as Arabic numerals, but in fact we know the Arabs themselves took the system from the Indians.

Many of the ideas in maths that we have from the Greeks probably came from the Babylonians, and other Mesopotamians (and maybe some influence from the Indians as well).

No doubt the ideas the Greeks took on board they combined in new ways, and extended further.

If you say something to someone often enough (and coca cola advertisers among others are very well aware of this effect) they will come to accept it.  So, has science brain-washed us into accepting things that are not at all reasonable? 

But the point you are missing is that science is not about things being reasonable or not - it is about creating a model of the universe that works, and can be proven to work by being used and tested.

Science is 'proven' not by looking pretty, but by showing that its predictions work.  If the predictions don't work, then the idea is rejected.  This is different from Coca Cola ads - the advertisers don't actually need to prove anything works.


On the other hand, I could turn round and say, do you have any reason to suppose things are the same at the other end of the universe?  And what?  You put the onus on me to justify what I am saying and say that if you do not KNOW things are different, then you have to think they are the same?  No to that.

It is easy to say that things are different at the other end of the universe, but that is in essence a negative statement - it says what you don't believe.  Would you care to be more positive, and say what you believe the laws of the universe are at the other end of the universe, in a positive way?  As I said, science is proven by predication, but negatives don't help with prediction.  If you have a more positive idea of what is at the far end of the universe, then you can start to make scientific predictions, and then the predictions can become testable.


I do hope scientists are as robust as they seem.  I am poking and proding, but then, they do actually profess to hold a defensible position, and to welcome scrutiny!

Robust?  In what way?

In very simple terms, science has made predictions, and most of those predictions have been proven to be true (if that was not the case, as I mentioned above, the theory is rejected).

Clearly, there are some cases where science does not get it right, and that is where new theories have to be proposed to make better predictions.

It is possible that someone can create a different model that can make as good predictions as present scientific theory; but if you believe you have a better model, then you have a lot of work ahead of you to demonstrate that the predictions work.

It would be foolish to believe science is perfect, but nothing ever is.  The question is whether there is anything better around.

If you mix two chemicals together, do you have a good theory that will predict the outcome?

If you place a piece of metal under stress, do you have a good theory that will demonstrate when the metal will fail, and how far it will bend before it breaks.

These are the sorts of questions which science has to answer.  If it comes up with the wrong answers, then it is bad science.  It may not be perfect, but do you really wish to throw out the baby with bath water.

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Offline rainwildman

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I am going to make this my last post, because I can see the big guns are coming out and I am beginning to get the 'you have no right to talk about science because you are not qualified' ....well it so happens that I am.  Nothing I have said about my past is a lie ... other than by omission.  I omitted to say that before I became an artist I was a physicist, and have all the publications, patents, lettere after my name etc to prove myself.  But I do not like to stand on my qualifications (I find it intimidates people) and the question I have been raising here are precisely the things that troubled me enough to make me quit and go elsewhere to look for a life.

And let me be more specific.  Back in the 1970's, for my doctorate, I was trying to create what is known as a 'number state beam', that is a beam of light that is in a 'number state'.  What is intersting about that?  That it would have been the first time anyone had created anything that was purely a quantum state, that is, a state that is DISALLOWED by classical theory.  Do you see what I am saying.... that after half a century, no-one could justify having adopted the horrendously difficult quantum theory in preference to the much simpler classical theory ... quantum theory became orthodoxy on a vote, in the 1930's .... it was politics .... guess who was on the voting committee.... yes, you've guessed, the very people who had derived quantum theory and had a vested interest in making it the orthodoxy.

And that leads on to what I did later, which was go into the real world and work with optical communications, including optical computers.  And do you know what i found?  In the world of technology, in the real world, PHYSICS IS  NO DAMN GOOD.  It is just not up to the job of dealing whith the real world.  The real world is much to complex, and one has to derive the appropriate maths to deal with each situation.  so what are we spending so much time and money on physics for? 

Prediction... is it desirable?  Actually, no.  It is inhuman and a nightmare to know the future.  And don't give me global warming and all that .... that game, of raising up the monster and then defeating it as an age old trick use by religions to gain converts!  And, if you really think scientists can make predictions about climate change.... no, they can't.  That is MUCH MUCH too complicated.  It cannot be done.

And, as for simplicity etc and other ways of doing things .... yes, as a  matter of fact, there is .... it is called EVOLUTION.  That is how nature deals with complexity.  That is how complexity should be dealt with.  That is how you can create and deal with computers and fast cars WITHOUT RECOURSE TO OVERSIMPLIFIED AND BLINKERING theories such as current physics offers.  And it is how you can get past the inhuman practice of divining the future!

Well, i guess if I had not worn out my welcome before, I will have thoroughly done so now.  So, goodbye all. 

PS truth really does matter, not for the sake of fast cars or the future of the world, but for your individual mental health ....  but that is a whole other issue concerning the effect of good and bad behaviour on your mental health.

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lyner

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If you wait a few years and your idea is valid, someone else will champion it and it will become accepted. Otherwise it will join the host of other theories which didn't make it.
It's a tough business and changing the World (or the World view) is not for the fragile. If you are really sure about your theory then follow it up.
Or have you ever considered that you could just be wrong?

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Offline Soul Surfer

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Rainwildman.  You are probably correct when you say that in some places (and times because that's just the same thing) the laws of physics within our universe were significantly different from the ones we observe locally and many reputable scientists will agree with this.  It is just that you have not got a good grasp on what scientists mean when they say locally.  As I have already stated  we can see clearly and measure the laws of physics out to red shifts of 1000  that is when the universe was a few hundred thousand years old and was about as dense as and as hot as the surface of the sun and can model the universe accurately back until it was denser than an atomic nucleus so all this time and space is by definition local.  However we have every reason to believe that our universe is much bigger than this by many times but unfortunately we cannot observe these regions.

If you really wish to learn about this and precisely how we know about it I can thouroughly reccommend  the book "The Universe a Biography"  by John Gribbin
ISBN  978-0-141-02147-8 a paperback costing in the UK  £7.99.  I am just finishing reading it and it is the best book I have read on this subject in a long time and I learned quite a lot from it.  It takes a completely new route to describing these things and is not just a copy of what other people have written on this subject.  it state things clearly and concentrates on getting things in context and avoids a lot of the rubbish "Gee Whiz!" type pf science  
Learn, create, test and tell
evolution rules in all things
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Offline Soul Surfer

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Rainwildman I see that while I was writing my last reply you have come out of the closet and shown yourself to be a bitter and twisted troll.  I have worked successfully on technological innovation all my life and disagree totally with you about the "laws of physics". 

The problem is not with the rules of the game but some people's understanding of them.  I have many times been told that things are impossible only to prove them possible once you understand properly how things really work.  All the laws and the derived rules of thumb for working are approximations and it is vital to know where the approximations fail and new rules of thumb have to be made.
Learn, create, test and tell
evolution rules in all things
God says so!

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lyner

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That is one of the refreshing aspects of modern Science; any Scientist worth his/ her salt is only too aware of being a link in a whole matrix of knowledge and that the best we can hope for is to know a bit more than we did yesterday. Nothing is absolute.
Never throw your toys out of your pram - you may need one of them some day.

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Offline johnbrandy

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Responding to the initial question, "do the the fundamental laws of physics relate to the 'entire' universe"? The question as to whether such laws applies to the entire and therefore unknown conditions of the universe are interesting, and fall within the domain of thought experiments. To ask if established and testable laws of physics apply to aspects or areas of the universe that are, as yet, not known or understood, is tantamount to speculating upon that which is unthinkable. No doubt, extrapolating from the known to the unknown is often the only mode to infer probable conditions of the unknown. This is a useful method, and often leads to consistent results. Notwithstanding, it is impossible to know if established laws of physics apply to the entire universe. I doubt if any reputable scientist would suggest as much. Scientific knowledge is provisional. Laws, and especially theories, (in this case of physics), are by definition, provisional, therefore, the notion that the laws of physics apply "everywhere" is not only unknowable, but impossible to conceive; with respect to the limited knowledge of the known universe, and the total lack of knowledge of the "entire" universe. Thank you for allowing me to contribute to this discussion.   
« Last Edit: 03/06/2008 05:14:02 by johnbrandy »

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Offline bitistoll

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Hi, I,m back!  'Bitter and Twisted Troll', alias 'bitistoll' (get it? BITer and twISTed trOLL?), alias rainwildman.   I just love that epithet and could not waste it... bitter and twisted troll, all those 't' and 'd' sounds just trip along, onomatopea, pure poetry, I love it.

So why is she back?  Because mummy is needed to bring some order to this site.

I have been round and about the internet quite extensively, and my explorations have taken me to many discussion forums, and I have found that there is a pattern, and it is exibited here as much as everywhere else.

These forums are make an ideal playground for bullies and teases.  They get into a little gang and patrole the site like guard-dogs ready to savage anyone who enters their territory ... and that is what they are about, that is where they get their kicks.  All else is just pretence and empty noises.

I know the type well.  I had an older brother who was just the same.  He only ever joined in my games so that he could spoil them, break my toys, and give me a thumping!  My first recourse, and a wise one it was, was simply to refuse to play with him.  But lord he could be persistent!  Eventually I would succumb to emotional blackmail (how can you be so mean? and the like) and the result would be the broken toys, the spoiled game and the thumping.  I once asked mother why she never interfered, never stopped him or gave him a row for such bad behaviour, and she gave me what was probably the most valuable gift she ever gave me, a 'pearl of wisdom,.  She said, 'it's your own fault.  IF YOU DID NOT REACT HE WOULD NOT DO IT.'

Now harsh that seemed, loading the onus for his good behaviour onto me.  But she was right.  The world is full of bullies and teases and once you know how, and once you can identify the type, they are very very easy to deal with.

You see, they are like little boys throwing stones at dogs: when the dog howls and runs around trying to dodge the stones and cowers with its tail between its legs, that is what they get off on.  If the dog were to completely not react to the stones, they would soon get bored and go off to cause trouble elsewhere.

So that is the nature of the hard-core that skulk around these forums arguing and bullying and spoiling it for those who actually want to discuss things.  And that is what concerns me... those of you out there who actually WANT to understand things, to learn and discuss and do all the things that these boards, on the face of it, are supposed to do... you need to know what you are dealing with and how to take care of it.

And this is how: DO NOT PLAY WITH THEM.  That is, when you have identified the ones that come on scary, the hard-core, then DO NOT REACT TO THEM.  Do not argue with them, do not respond when they try to argue with you.  Talk to other people who are trying to have a decent discussion and ignore the interjections of the teases and bullies.  Above all, DO NOT BE AFRAID OF THEM.  They really are not dangerous at all.

The thing is that by their bad behaviour they do themselves more damage than anyone else, and the damage they do themselves is to lose sight of reality, of truth.  They tell lies and try to trick you and play all the games beloved of arguers, and that is not about truth, it is about winning an argument by any means possible, including lying.  You have to SOUND good though, and that is what does the trick.  But if you find yourself reading down the posts these people are posting, and you find you are having difficulty grasping hold of things, difficulty understanding what they are saying, believe me, THE FAULT IS NOT YOURS.  IT IS NOT THAT YOU ARE STUPID, BUT THAT THEY ARE SAYING NOTHING.  They spout good sounding, but empty phrases that they have  learnt parrot-wise.  The WHOLE POINT IS TO INTIMIDATE, SO DO NOT SUCCUMB.

I have onserved that there are a lot of people looking at the posts I have put up, but blessed few of them open their mouths.  I only hope this goes some way to remedy that situation.