What if the rules of physics are NOT the same everyywhere?

[kirkster501]

We assume galaxies and everything are the distance they are because we assume red shift is a phenomena similar to that here. But what if the rules are not the same? Who said they should be and why? Why should we be relying on "common sense" that the rules are the same everywhere? What if what appears to be redshift is because a different force is at work? One we wont understand for another thousand years?

Ditto another observed phenomena.

"There are more things in heaven and earth....."

[Photosbykev]

Personally I think we are still at the caveman level of understanding the physical world.

[Mattscar]

Its one of those 'As far as we can tell at the moment' kind of rules I think. But thats the great thing about science in general, if someone can come along and prove there is another force out there, the book would be re-written

[kirkster501]

Personally I think we are still at the caveman level of understanding the physical world.

+1 Fantastically well said. That's where I am coming from.

I think mankind has done brilliantly well to understand as much as we do. But I think the universe and even the earth is massively more complex than we can even begin to understand. I think there are forces at work that we may not discover for another 10000 years. Or more.

[ollypenrice]

The idea that the universe is the same everywhere has never been taken for granted. EInstein and others felt that it was an assumption they had to make in order to get a working hypothesis under way. It was never anything that they asserted to be the case. We are now in possession of data which will allow us to inch towards the next stage and get beyond the need for that initial assumption. Very exciting. Maybe the universe isn't the same everywhere and maybe we'll learn about that.

The reshift is not the only distance measurement tool. Galaxy distance can also be estimated by the Tully Fisher relation and by an assortment of Standard Candle techniques. There has been a huge debate about the reshift. The great spokesman for the doubters was Halton Arp.

There's a danger in these threads of people popping up and saying, 'Aha, those clever types haven't thought of this, though, have they!' Well, yes they probably have. The best insights into what my be wrong with the way we think are to found by reading the big thinkers. They are the ones who have usually given the shortcomings of science the most thought and the deepest thought. Sometimes, though, they just have to say, 'We don't have the information needed to avoid this assumption so for now we'll live with it and see where it leads.' When it leads to a contradiction that's good because it forces us to backtrack and try again.

Olly

[acey]

The universe obviously isn't the same everywhere - the centre of the sun is very different from interstellar space or someone's living room. The question is whether the same laws of physics apply everywhere.

Suppose that in the centre of the sun the laws of physics are Set A and in someone's living room they are Set B. Then physicists would want to know why they are Set A in one place and Set B in another; they would look for the general principles that determine which rulebook applies in which sort of place. This would be Set Z: laws of physics (or meta-laws) that apply everywhere. It's not an assumption, it's what they're looking for, even if they may not have found them yet.

This is all to be distinguished from the cosmological notions of homogeneity and isotropy, which are testable assumptions.

[ronin]

I think they have to be the same everywhere, we may not know all of them but no difference.

A simple aspect is quantum tunnelling, if the effect was greater or lesser then stars either would not exist as fusion would not occur, or they would exist for a very short time - as in how long it took for a hydrogen bomb to go bang.

Also the idea means that the big bang was different in one place then another, as in these laws can go work over here and these others one can go work other there.

Another universe will have different laws and it may or may not be a stable one, when I get my tardis repaired I will have a look into a few of them.

So maybe we don't yet know all of them, and we most likely do not fully know the detail of the ones we have so far come up with. However not knowing either at all or fully is not the same as different laws.

[Mattscar]

Another universe will have different laws and it may or may not be a stable one, when I get my tardis repaired I will have a look into a few of them.

Shotgun!

[JamesF]

The principle that the same physical laws apply everywhere (in the observable universe, at least) is, I think, an assumption you have to make if you want to attempt to explain the observable universe in any meaningful way. If we were to assume the opposite -- that all physical laws vary, then obviously there could be no predictable laws that would explain how and where they could vary otherwise they'd be fundamental laws that didn't vary and your initial assumption would have been broken. But if there's no telling how physics might work at any given point in space time, how could you meaningfully make any attempt to understand the universe?

In order to make progress therefore, it's reasonable to assume that the same laws hold everywhere and to feel that the assumption is fair as long as the predictions made by theories relying on it are validated in "the real world". If however there comes a point when they aren't, physics may have a fairly serious headache to deal with.

James

[floppygoose]

The principle that the same physical laws apply everywhere (in the observable universe, at least) is, I think, an assumption you have to make if you want to attempt to explain the observable universe in any meaningful way. If we were to assume the opposite -- that all physical laws vary, then obviously there could be no predictable laws that would explain how and where they could vary otherwise they'd be fundamental laws that didn't vary and your initial assumption would have been broken. But if there's no telling how physics might work at any given point in space time, how could you meaningfully make any attempt to understand the universe?

In order to make progress therefore, it's reasonable to assume that the same laws hold everywhere and to feel that the assumption is fair as long as the predictions made by theories relying on it are validated in "the real world". If however there comes a point when they aren't, physics may have a fairly serious headache to deal with.

James

Well summed up

[Treeden]

... In order to make progress therefore, it's reasonable to assume that the same laws hold everywhere and to feel that the assumption is fair as long as the predictions made by theories relying on it are validated in "the real world".

I think that is right James. We have to make a least this basic assumption, otherwise we have no platform to build upon. As long as we always keep an open mind and always entertain the possibility that we are wrong.

... If however there comes a point when they aren't, physics may have a fairly serious headache to deal with.

Rather like the moment when Truman’s yacht is brought to a very sudden stop as it hits the end of the world.

[kirkster501]

Well, my reasoning is that its is a clear fact that stars *exist* in other galaxies (or to be controversial what we *think* to be other galaxies). There can be no doubt there. So it would be reasonable to assume that the laws of gravity, fusion, light propagation, stellar evolution must be the same as here. IF those laws are teh same then why shoud other laws be different?

That said, ARE these galaxies that remote? If these theories were out in some way then the whole evolution of the universe, dark matter, expansion of the universe argument crumbles.

[Macavity]

I claim *heuristically* - A favourite saying of a Mathematics for Physics lecturer, I knew!

(After not saying it for several lectures, he got a resounding CHEER, when he relapsed!)

To the challenge: "You Scientists know nuffing" - I found it best to move along the Bar?

As Olly says (so articulately!) there are many reasons why galaxies are at known distance.

Astrophysics... Particle Physics... have "problems" - Challenges are nothing new. But would we have it any other way? Therein lies the FUN of science? OLD Theories are rejected, only to reemerge with modified parameters. I feel quite *strongly*, we are NOT "in the stone age" re. science. I speculate that we have it BROADLY right! The thread (cheerfully) prompted me to (fairly randomly!) find:

http://en.wikipedia....riele_Veneziano

Not without its detractors, "String Theory" dates back to 1968!

Far before Quantum Chromodynamics. Yet still revisited...

[ollypenrice]

I'm not quite sure what is meant by 'a law of physics' and I wonder if it is a phrase which we would be inclined to coin if starting from today? It implies a kind of certainty which modern science seems to have set aside. Perhaps I'm wrong?

I don't think we are in the stone age of understanding, either. I think that there are almost certainly things which are unknowable but that simply means that you can be in any 'age' of understanding you like and you still won't know them. So I don't think we know anything about what cannot be known, other than that it probably exists, but I suspect we know quite a lot about what can.

I don't believe that the rough distance estimates to galaxies are going to get thrown out of the window. I think they'll be refined. And I don't think this is the problem anyway, nor is it the way a future great leap in understanding will go. What I think is far more pressing is a further rethink of what time and distance are, how they relate to each other and how they may relate to other dimensions in a wider matrix. At the present we don't, so far as I know, have a clear idea of how to search for other dimensions but it would go against history to assert that we will never be able to do so. We might, or we might not. But I do think that what we maen by the distance to M31 is going to remain more or less that - a good estimate of what we mean when using the term distance as we are using it now. But maybe we'll find a short cut!

Am I right in thinking that the OP has a sub text along the lines of 'we take our theories too seriously?' My instinct runs the other way. Maybe we don't take them seriously enough.

Olly

[kirkster501]

Am I right in thinking that the OP has a sub text along the lines of 'we take our theories too seriously?'

Well, you seem to read me very well Olly. I do think we take them too seriously...!

[ollypenrice]

Well, you seem to read me very well Olly. I do think we take them too seriously...!

OK, but here's an example of the reverse. Before Einstein at least two people (Lorentz and FitzGerald) realized that if you pretended that time could slow down for a speeding observer and that space could contract in the direction they were speeding then Maxwell's equations would stand. However, as I understand it they considered this just a mathematical game. They failed to take it seriously enough because, perhaps, they put 'common sense' first. It took Einstein to come along with the courage to think the unthinkable, that neither time nor space were constants. He also dismissed common sense as 'that set of prejudices accumulated by age eighteen.'

There are plenty of examples of scientists not taking themselves seriously enough. Even Hubble (who took himself incredibly seriously!) never accepted that he'd discovered the expansion of the universe. Penzias and Wilson didn't, till Robert Dicke told them otherwise, believe they had discovered anything real with their Bell Labs radio telescope. They had, in fact, discovered the cosmc microwave background but they thought it was noise. Prior to Jocelyn Bell another radio astronomer had found the signal from a Pulsar but had dismissed it as system noise as well. The Pope told Gallileo that, OK, his solar system model worked for predicting planetary motion but that was it, it didn't describe reality. Common sense again. We can feel that the earth isn't spinning or orbiting, right? Uh-oh...

Olly

[JamesF]

I'm not quite sure what is meant by 'a law of physics' and I wonder if it is a phrase which we would be inclined to coin if starting from today? It implies a kind of certainty which modern science seems to have set aside. Perhaps I'm wrong?

I can see that there may be a danger of some sort of disconnection between what a scientist means by a "law" and what the man in the street understands by it, just as there is with the term "theory". In that sense perhaps it's not as helpful as it might be that the phrase is used and that some term that has no other interpretations isn't used.

From my point of view I think a scientist would say that a "law" within any given area of theory is either an axiom of the system (ie. something that is assumed to hold true at all times without further proof) or a result that can be derived from them and would understand that laws may "break" if the axioms can be shown to be invalid.

It's perhaps not entirely helpful to the layman that laws that have been shown to fail sometimes still retain their name, perhaps because within the context of their application they remain useful.

James

[Qualia]

The way I understand the situation is that all theories are regulated by a metaphysical view on the nature of reality.

Metaphysical views carry assumptions and implications on how discourses are to be understood and relate to each other. Metaphysical theories of reality select a basic property and/or law given to human experience. These properties include but are not limited to mathematical, spatial, temporal, physical, biological, psychological, logical, historical, social, economical, political. ethical, spiritual, mental, linguistic, and so on.

These metaphysical properties can be termed aspects of a human reality; we discern that things 'change' and follow 'patterns', 'principles' and 'rules'. The basic nature of reality is identified with one or two properties and then theories are built up from them. Metaphysical theories are defended by arguing that the property identified really does exist in reality and hence metaphysical theories are ontological.

If we accept that the term metaphysics consists of theoretical assumptions adopted as the standard for the normal way of inquiry, then all theories are grounded upon certain assumptions, all concepts are metaphysical, even the very term itself.

What happens here at this junction is an interesting problem which has some 2,500 years of debate and discourse behind it. Fundamentally footnotes to the Platonic problem of Universals.

Once we accept that there does appear to be 'rules', 'patterns', 'principles' in reality we can ask ourselves what is the reality behind those rules?

Do they have an objective, universal existence? And if so how do we 'grasp' them without falling back on metaphysical assumptions or begging-the-question type responses.

Are they conjured into existence by the human mind arising from our shared nature, DNA, cultural background? And if so, would other creatures see the world with a different set of rules and patterns, rendering the term universal mute?

Maybe there are no such things as rules and patterns, they're just features imposed by the human disposition to apply rules and patterns (do straight lines and triangles, numbers and corners really exist in nature beyond the human mind?).

I think you're right to raise objections and question the claim of Universals. The level of confidence to state without doubt such things would place the scientific and absolute image of the world comfortably in place alongside the manifest image; history is riddled with the evil produced by the ardent and enthusiastic hostility of true believers.

Thankfully, however, I think most serious scientists appreciate that their claims and hypothesis are inductive by application, falsifiable and thus reduce worrying cases of fantacism and certainty.

[ollypenrice]

So maybe all physical theories, models, laws, should have a prefix along the lines of 'Reality, as we are constrained to perceive it, behaves thus... E=MC squared, etc etc.'

I'd be happy with that. But within that constraint I'm impressed by scientific progress. When I started reading about astronomy about 17 years ago I used to think, 'Hang on, why do they think that? It's crazy, it's surely running ahead of the evidence. But with more reading I found that there was more evidence than I was previously aware of and that, remarkably enough, I was starting to believe it, by Gad! Doubt, yes, doubt is essential. But so are courage and the humility to realize that reality doesn't stop dead in its tracks because you tell it isn't being reasonable...

Olly

[Cath]

My thinking is that the 'laws of physics' will be an ever changing set of 'rules' governed totally by our own perception of the universe around us. That doesn't mean the rules we create are wrong or right, it just means we are doing our bestest with the tools at hand.

A big problem is that we have no idea what tools we are missing to allow us to see a better representation of the 'reality' of our predicament.

An example might be to work out how to describe sight to someone who has never had it - try it, it's not as easy as one might think.

If the person without eye sight had never been told about it then they would never know it existed. I wonder what senses (we as bio-beings on a lonely far off planet) we are missing, senses that could quite possibly explain so much about it all.

[ollypenrice]

My thinking is that the 'laws of physics' will be an ever changing set of 'rules' governed totally by our own perception of the universe around us. That doesn't mean the rules we create are wrong or right, it just means we are doing our bestest with the tools at hand.

A big problem is that we have no idea what tools we are missing to allow us to see a better representation of the 'reality' of our predicament.

An example might be to work out how to describe sight to someone who has never had it - try it, it's not as easy as one might think.

If the person without eye sight had never been told about it then they would never know it existed. I wonder what senses (we as bio-beings on a lonely far off planet) we are missing, senses that could quite possibly explain so much about it all.

Yes. We might be blind, among other things, to other dimensions - as well as to other things to which we are... blind! Hmmmm....

Olly

[mattft]

Flatland by Edwin Abbott is my favourite way to get me thinking about things like that.

[Qualia]

So maybe all physical theories, models, laws, should have a prefix along the lines of 'Reality, as we are constrained to perceive it, behaves thus... E=MC squared, etc etc.'

Ay, with regards to the previous post this is areasonable conclusion, but this position itself does run into trouble; a given scientist could ague that because our most respected theories have had more than amble empirical success, we can rid the world of that prefix and now assert rather forceably that these theories actually tell us how the world-is.

If we prefix our theories with the idea that they are constrained and conditioned by our ontological and physiological make-up, then what would stop some socio-economic and political theorist, for example, concluding that because a given and significant portion of our being is socially constrained and conditioned, then these theories will no doubt tell us less about how the world is and more about these social conditions? Our socio-economic theorist could argue that in a Victorian, capitalist system, the overt emphasis given to 'the survival of the fittest', for example, was merely a reflection of the prevailing (and current) ethos and can be easily countered by emprical observations of mutual support and aid found in nature.

If, for the sake of argument, our scientific theories are ultimately grounded on metaphysical assumptions, that they are inevitably prefixed by 'as constrained and conditioned and perceived by the given community', and thus are significantly conditioned by subjective values and our socio-economic and political systems, what is left of the scientist's sacred image of objectivity and the notion that these theories are really telling us something about how the world really is?

But within that constraint I'm impressed by scientific progress.

Again, just for the sake of argument, could this notion of progress (towards what...?) be countered by the idea of shifts? Rather than saying the geocentric theory cleanly progressed into the heliocentric theory of orbits, just as the number 1 cleanly progresses into 2 and 3 and so on, or after A, follows B and C, for example, what actually took place was a decidely different shift of thought both in terms of mathematical explanations of orbits and of a very different physical not to say existential perspective entirely.

For sure, a geocentrist and a heliocentrist could give the same mathematical description of the orbit of the planets, they do in this sense, relate to each other and could be said to have progressed, the former into the latter. However, the principle foundation and concepts in both theories, even if they retained the same names, have not only different meanings, but that the meanings will often exclude each other. They are thus incommensurable theories which contain concepts and principles without a common measure, so it is tricky to see how there has been a progression from one theory into the other.

The same could be argued with Newton's mechanics and Einstein's relativity. For example, Newton's notion of mass is conserved, Einstein's was converted with energy and although at low velocities these two masses could be measured in the same way, they cannot be conceived to be the same. Although both use the same term, mass doesn't really have the same meaning and thus exclude each other. This doesn't imply that one cannot derive Newtonian mechanics as a case of Einstein's relativity, but it does suggest that this special case is not Newtonian mechanics, but a substitute of it.

The point here, then, is could a given theorist argue that what is actually taking place in many examples in the history of science isn't progression of one notion or concept extending into another, so much as concepts literally replacing others and creating shifts in thoughts and theories and creating new models and ruling pardigms?

Sorry if this post has taken the OP off course.

[Cath]

Again, just for the sake of argument, could this notion of progress (towards what...?) be countered by the idea of shifts? Rather than saying the geocentric theory cleanly progressed into the heliocentric theory of orbits, just as the number 1 cleanly progresses into 2 and 3 and so on, or after A, follows B and C, for example, what actually took place was a decidely different shift of thought both in terms of mathematical explanations of orbits and of a very different physical not to say existential perspective entirely.

Well now theirs a thing! .. we are assuming that the technology we have discovered over the years is 'progress'. Well, up until now it has certainly made life 'easier' for a lot of humans so I guess you could say that's progress (for human's that is). But it's had quite the opposite effect for a lot of non-human life on the planet, it's actually been quite devastating for some.

Life itself does not in anyway need technology to live and survive on planet Earth, infact life in general has done far better in the past than it's doing today.

So, whether a certain way of life and any discoveries made is considered 'progress' or not is I'd say based purely on the beings point of view.

Technology (as we currently use it) may well be our undoing, If we don't face up to that in time then all the scientific theories in the world we have created will not matter in the slightest and will fade from existence just as quickly as they appeared. The Universe will however carry on as normal - without us.

[ollypenrice]

I quite agree that technological progress may be progress towards things we don't want!

However, could we not say that scientific theories progress in that they become more accurate descriptions. Maybe you won't like 'accurate' so perhaps I could substitute 'more general' or 'more complete.' I wouldn't want to imply that theories necessarily evolve, though. I see GR as entirely different from Newtonian mechanics for all their similarity at local scales. (On the other hand the shortcomings of Newtonian gravity were evident to Newton and... now I'm stuck. Was it Euler who asked 'What happens if the whole universe moves three feet to the left?' Or something like that. And Sir Isaac rejected the idea of action at a distance for all that his theory impied it.

I think that your hypothetical Victorian talking about the suvival of the fittest was misunderstanding the term 'fittest' as used by Darwin, no? But I take your real point. (An historical aside but what the establishment disliked about Darwinism was that it seemed to reverse the top down hierarchy, as they saw it, and carried with it the dangerous idea that a factory underling or farm labourer might evolve to rival a gentleman. And that would never do!)

The history of ideas. Wonderful. Why do we only get the history of politics in school? I'd far rather study the history of ideas.

Olly