Did Einstein overthrow Newton?

[Pinball1970]

It is a question but not a great question since it gives only two options, yes or no and that scrapes the surface (for me) what science is meant to do and how it evolved in this case.

My position is that the approaches by these great minds were different, different century, different context and different shoulders of giants that they were standing on.

My example was cannon balls because cannon balls were important in Newtons time but the word I used was context, "Domain" is a better word.

So for me the simple is no, Einstein did not over throw Newton because Newton does just fine in the areas of that domain, it works.

He was wrong about certain features of the universe such as universal time and was not aware of relativistic effects but this does not upend his domain.

I think the diagram illustrates this better than words.

 

[Gawdzilla Sama]

Some folks flock to bright shiny new ideas, others recoil in horror at disrespect to old cherished ideas. We'll get both sides whenever things get updated.

 

[origin]

So for me the simple is no, Einstein did not over throw Newton because Newton does just fine in the areas of that domain, it works.

This is correct IMO. Newtonian gravity is modeled as a force and it works perfectly well to to fly a space ship to mars. General relativity models gravity as a warping of spacetime. Einstein's model is more precise and addresses some discrepancies in Newtons model.

 

[Pinball1970]

old cherished ideas.

My point was that some of those work just fine depending on what you want to investigate, if it is the moon, rockets, cars and cannon balls I apply Newton.
If I am looking at electrons I need QM.

 

[Pinball1970]

This is correct IMO. Newtonian gravity is modeled as a force and it works perfectly well to to fly a space ship to mars. General relativity models gravity as a warping of spacetime. Einstein's model is more precise and addresses some discrepancies in Newtons model.

Yes and both are approximations because there are still missing parts to the jigsaw.

 

[Gawdzilla Sama]

Oh, I agree. The type of response is dictated by the level of operations. Two of my best friends were pretty much the fighting team from "Thunderdome". "Bert" was the big guy and "Ernie" was the ... jockey. Good representation of physics as a whole, IMNSHO.

 

[axocanth]

It was this task to which Einstein boldly dedicated himself, and with the dazzling framework he developed after close to a decade of searching in the dark, Einstein overthrew Newton's revered theory of gravity.

- "The Fabric of the Cosmos", Brian Greene, p64

It should be recalled that at the end of the nineteenth century, physicists widely believed that classical physics gave the general outlines of a complete mechanical explanation of the universe. Since then, relativity and quantum mechanics have overturned such notions altogether . . . Classical physics was swept aside and overturned . . . Is it not likely that modern molecular biology will sooner or later undergo a similar fate?

- David Bohm, essay "On the subjectivity and objectivity of knowledge"





The consensus view so far (Pinball and Origin) is that Einstein did not overthrow Newton. But there's an obvious problem, well, two actually: Brian Greene and David Bohm!

It's not just Greene and Bohm, of course. Physicists, including the very finest, commonly make the same assertion, though the locution may differ slightly in each case (See "Is the theory of punctuated equilibrium . . . ? ", post 85).

Now if it was just Joe Sixpack on the streets of darkest Manchester saying that Einstein overthrew Newton, members here might plausibly dismiss his claim on the grounds that he doesn't know what he's talking about. Presumably we can all agree that such a tactic just won't work in the case of people like Brian Greene and David Bohm. Unless you're going to write them off as confused, or hyperbolic drama queens, or incompetent users of the English language -- surely not! - we have to take them seriously.



Before we can even begin to make progress in this thread, then, perhaps we need to get more clear about what is meant by the word "overthrow". For example, for a theory to be overthrown does it mean:


(i) The theory stops working. The theory ceases to yield predictions that are accurate.

If overthrown is understood this way, we risk degenerating into triviality; it may turn out that no theory in the history of science has ever been overthrown. Phlogiston theory and the geocentric theory, just to name two, were not overthrown, as the word is now being characterized. If members here are satisfied with this result we can stop right now, and head down to the pub -- the drinks are on Pinball -- our work here is done! If not . . .


(ii) The theory is no longer regarded as an accurate representation of reality; scientists (mainly) no longer believe our universe is like that. It has been replaced by a new and conceptually different theory which scientists place more stock in.

This, I suggest, is what David Bohm and Brian Greene mean by "overthrown". Compare:

The two theories of relativity are among humankind's most precious achievements, and with them Einstein toppled Newton's conception of reality. Even though Newtonian physics seemed to capture mathematically much of what we experience physically, the reality it describes turns out not to be the reality of our world. Ours is a relativistic reality. Yet, because the deviation between classical and relativistic reality is manifest only under extreme conditions (such as extremes of speed and gravity), Newtonian physics still provides an approximation that proves extremely accurate and useful in many circumstances [cf. it works - axo]. But utility and reality are very different standards. As we will see, features of space and time that for many of us are second nature have turned out to be figments of a false Newtonian perspective.

- "The Fabric of the Cosmos", Brian Greene, p10


Do members here feel that, on this second definition, classical Newtonian theory was overthrown? Or do you still take Newton's absolute space, absolute time, and attractive gravitational force seriously as real features of our universe and reject Einstein's alternative ontology?



Or do members have still something else in mind by "overthrown"?

 

[axocanth]

This is correct IMO. Newtonian gravity is modeled as a force and it works perfectly well to to fly a space ship to mars. General relativity models gravity as a warping of spacetime. Einstein's model is more precise and addresses some discrepancies in Newtons model.

Do physicists (by and large) still believe this attractive force is real? That is, do they still believe that Newton's concept of an attractive gravitational force answers to anything in reality? And if not, is it reasonable to say that this concept has been overthrown and replaced by Einstein's new ontology?

Is it possible that gravity is both an attractive force and the warping of spacetime? Is this what you believe?

 

[Pinball1970]

Do physicists (by and large) still believe this attractive force is real?

"Real" in physics gets complicated real quick. We could have a whole thread about what you mean by things like, real/realism.
I have observed such a conversation on another platform- they all disagreed but then they acknowledged that they were quite happy to go back to the lab and do some useful physics.

For me? I do not care that much, where will my cannon ball fall? On the ship or will I over shoot? I better get Newton on the case to work this one.

 

[axocanth]

"Real" in physics gets complicated real quick. We could have a whole thread about what you mean by things like, real/realism.

etc.

No one ever listens to me lol, so I brought some friends . . .


"We can indeed see from Newton's formulation of it that the concept of absolute space, which comprised that of absolute rest, made him feel uncomfortable; he realized that there seemed to be nothing in experience corresponding to this last concept. He was also not quite comfortable about the introduction of forces operating at a distance. But the tremendous practical success of his doctrines may well have prevented him and the physicists of the eighteenth and nineteenth centuries from recognizing the fictitious character of the foundations of his system."

- Albert Einstein, "On the Methods of Theoretical Physics"


"The one or the other is, however, being rendered much more difficult because it is by no means immediately clear what is meant by "classical theory". Newton's theory deserves the name of a classical theory. It has nevertheless been abandoned since Maxwell and Hertz have shown that the idea of forces at a distance has to be relinquished and that one cannot manage without the idea of continuous "fields". "

- Albert Einstein, "Reply to Criticisms" ("Albert Einstein: Philosopher-Scientist", p675)


"As far as we are able to judge at present, the general theory of relativity can be conceived only as a field theory. It could not have developed if one had held onto the view that the real world consists of material points which move under the influence of forces acting between them."

- Albert Einstein, "The Meaning of Relativity", p134


"By 25 November 1915, Einstein had the final equations. Matter and energy were intimately linked with the geometery of space-time. Planets orbit Suns because the geometry of space-time around these massive bodies is curved, just as two drivers starting at the Earth's equator going north gradually approach each other because the Earth's surface is curved. There is no "force" pulling them toward each other. Einstein showed that a similar, albeit more complex kind of geometrical curvature can explain gravity."

- Jeffrey Crelinsten, "Einstein's Jury", p88


"Light, and all other physical phenomena, must travel on locally curved paths in gravity. This point strongly motivates the idea that gravity is an aspect of geometry and does not belong in the menagerie of forces!"

- John B. Kogut, "Special Relativity, Electrodynamics, and General Relativity", p198


"We already encountered one of the most surprising ones [= conceptual shifts - axo], the shift from Newton's gravitation theory to general relativity. The basic component of the former unquestionably was the gravitational force. But then general relativity theory asserted that such a force simply does not exist, and replaced it by something radically different, namely space-time curvature. This really was a "conceptual revolution", and others followed."

- Bernard d'Espagnat, "On Physics and Philosophy", p158



"Once Einstein grasped the concept of free float in 1908, he had taken a substantial step towards the final idea: Gravity is not a foreign and physical force transmitted through the medium that surrounds us. It is a manifestation of the curvature of that medium."

- John Archibald Wheeler, "A Journey into Gravity and Spacetime", p27



These are my friends. If you don't like them, I have others.

 

[Seattle]

It is a question but not a great question since it gives only two options, yes or no and that scrapes the surface (for me) what science is meant to do and how it evolved in this case.

My position is that the approaches by these great minds were different, different century, different context and different shoulders of giants that they were standing on.

My example was cannon balls because cannon balls were important in Newtons time but the word I used was context, "Domain" is a better word.

So for me the simple is no, Einstein did not over throw Newton because Newton does just fine in the areas of that domain, it works.

He was wrong about certain features of the universe such as universal time and was not aware of relativistic effects but this does not upend his domain.

I think the diagram illustrates this better than words.

View attachment 6174

Therefore there really is no "question" is there? I suppose it depends on how you define "overthrow" but one is more accurate than the other and conceptually both could be wrong but the more accurate one takes precedence at the moment.

As to whether Newtonian physics quit working, that's not a real question, is it? What was observed has to be part of any theory, and it is so there is no "overthrowing" unless that just means more accurate.

 

[Gawdzilla Sama]

Buddha save me from the folks who think we already know everything we need to know. (Non-aimed comment.)

 

[axocanth]

I fear some members are confusing epistemological issues (e.g. what we believe, what we can prove, etc.) with questions of pure semantics.

Let's start with an everyday example. Can a person -- without inconsistency and without equivocation -- assert (or believe) both "Paris is the capital of France" and "Paris is not the capital of France"?

I trust there's no need to answer. You can assert (or believe) one or the other, but not both. To assert both is to contradict yourself. Of course, one can also withhold from asserting or believing either (e.g. "I have no opinion on the matter").

Consider:

This is correct IMO. Newtonian gravity is modeled as a force and it works perfectly well to to fly a space ship to mars. General relativity models gravity as a warping of spacetime. Einstein's model is more precise and addresses some discrepancies in Newtons model.

Gravity can indeed be modelled as an attractive force (Newton) and as spacetime curvature (Einstein), and if a scientist (or anyone else) treats these things as nothing more than models or instruments, no contradiction arises. Such a person is treating the respective theories as mere tools, and tools do not make any assertions about how the world is. Tools do not make any assertions at all.

A person treating the models in this way is known as an instrumentalist.


On the assumption that the two models/theories are mutually inconsistent, however, can a scientist assert (or believe) both? Can a scientist, for example, assert without inconsistency both that space is absolute and that space is not absolute? Without contradicting himself, can a scientist assert both that gravity is a force and that gravity is not a force (it is, rather, the curvature of spacetime)?

Is it, or is it not, the case that -- on pain of inconsistency and contradiction -- if a scientist asserts one theory he must deny the other?

Which of the two theories did scientists (by and large) assert 200 years ago?

Which of the two theories do scientists (by and large) assert today? And if they assert Einstein's theory and deny Newton's, is it reasonable to say that Newton's theory has been overthrown?


Which one do you assert? Einstein? Newton? Both? (that makes you inconsistent). Neither? (that makes you an instrumentalist).

 

[axocanth]

As to whether Newtonian physics quit working, that's not a real question, is it? What was observed has to be part of any theory, and it is so there is no "overthrowing" unless that just means more accurate.

Using Newtonian mechanics we can derive the location of Pluto, say, in exactly 200 years from now.

Is it your position that this derivation is part of Newton's theory? Newton was not aware of Pluto's existence.

 

[axocanth]

No one here seems to feel that Newton's theory was overthrown. Fair enough (maybe).

Can those who deny that Newton's theory was overthrown give us an example of a scientific theory that, in your opinion, was overthrown?

What are your reasons for applying the word "overthrown" in this case (but not in Newton's case)? Please explain.

Or are there no such theories?

 

[axocanth]

Consider what Brian Greene says again (post #7) . . .

"The two theories of relativity are among humankind's most precious achievements, and with them Einstein toppled Newton's conception of reality. Even though Newtonian physics seemed to capture mathematically much of what we experience physically, the reality it describes turns out not to be the reality of our world. Ours is a relativistic reality. Yet, because the deviation between classical and relativistic reality is manifest only under extreme conditions (such as extremes of speed and gravity), Newtonian physics still provides an approximation that proves extremely accurate and useful in many circumstances [cf. it works - axo]. But utility and reality are very different standards. As we will see, features of space and time that for many of us are second nature have turned out to be figments of a false Newtonian perspective."



Which theory is Greene asserting? Which one is he denying? Could he assert both without contradicting himself? Could you or anyone else?

Which one of the two theories do you assert/believe? Or do you have no opinion on the matter? -- both are simply tools which makes no assertions about reality, therefore explain nothing, bring no understanding whatsoever, and are neither true nor false.

 

[DaveC426913]

He was wrong about certain features of the universe such as universal time...

I am not sure this is warranted. I don't think Newton ever made any claims about universal time.

I think what he did was quantify the world we know without using time as a dependency. As was correct. It was simply not involved in any of what he developed.

In other words, we only started calling it Universal Time when Einstein's relativistic time needed to be distinguished from it.


eg: If a century from now, we discover, say, the higher spatial dimensions of string theory at the bottom of a neutron star, it does not follow that 20th century scientists were "wrong" about the perfectly valid physics we've done in 3 dimensions. Outside of the special case of neutron star cores, it all works perfectly well with 3 dimension-variables.

Only in the next century would we start calling 20th century science "3-dimensional physics" as a way of distinguishing it from "10-dimensional physics".

Yes?

 

[Pinball1970]

I am not sure this is warranted. I don't think Newton ever made any claims about universal time.

He used time in his equations in terms of derivatives of displacement and velocity, orbits of the celestial bodies, tides etc.

Is there an indication in his that the time and space these motions and forces operated in was malleable?

 

[Pinball1970]

I don't think Newton ever made any claims about universal time.

He said this apparently (source Wiki)

Absolute space, in its own nature, without regard to anything external, remains always similar and immovable. Relative space is some movable dimension or measure of the absolute spaces; which our senses determine by its position to bodies: and which is vulgarly taken for immovable space ... Absolute motion is the translation of a body from one absolute place into another: and relative motion, the translation from one relative place into another.

Not sure I understand his distinctions

 

[exchemist]

He said this apparently (source Wiki)

Absolute space, in its own nature, without regard to anything external, remains always similar and immovable. Relative space is some movable dimension or measure of the absolute spaces; which our senses determine by its position to bodies: and which is vulgarly taken for immovable space ... Absolute motion is the translation of a body from one absolute place into another: and relative motion, the translation from one relative place into another.

Not sure I understand his distinctions

The way I read this, Newton is just explaining Galilean relativity and contrasting that with some idea of an absolute frame of reference.

I have read that Newton was troubled by rotary motion and the idea of centrifugal "force". He realised that rotation should, by rights, be relative motion, just as linear motion is. Yet it appears in a sense absolute, since if you spin a bucket of water hanging from a rope, the water climbs up the sides, but if you leave the bucket alone and spin the room, the water does not climb up. I understand he concluded that rotary motion had be defined relative to "the fixed stars", i.e. the rest of the universe. So he was forced to consider a form of absolute frame of reference, to supplement Galilean relativity. (It's years since I read about this so forgive me if I'be got it a bit wrong.)

I also seem to recall Ernst Mach also wrestled with this issue in the c.19th, to some extent prefiguring Einstein's GR.