Depends on how you define "wrong."

Newtonian physics is a very well defined, functional and "correct" model of the physical universe. It is taught to all physics students as standard fare. However, once you begin studying smaller and smaller objects Newtonian mechanics break down and become inaccurate. That does not make it wrong, just not "all inclusive."

Quantum mechanics is where we study the very small (atoms, molecules, etc) in physics. Once again, it works. It can predict natural phenomenon. Is it "right?" No. It's is our mathematical model for small objects.

Similarly Einstein's relativity is only as accurate as the domain to which we apply it. One day, we will find that it fails to explain some phenomenon. Once again that does not make it "wrong."

To think of this another way:

Consider an electron zipping through a magnetic field. Does the electron refer to its vast knowledge of quantum mechanics to determine its trajectory? No. The electron just acts. We as humans try to fit its behavior to a mathematical model that is accurate to within some tolerance level.

When you toss a ball to a friend, do you mentally calculate the force you launch the ball at in numbers? Do you plan what angle your arm will be at relative to your horizontal axis when you release it? Does your friend calculate your height, and the relative height from which the ball is launched from you to him? Does he determine what angle to bend his arms to intercept the ball? The answer to all of the above question is no. You act to throw the ball, he catches.

Physicists, mathematicians, chemists, etc. We are in the business of analyzing physical phenomenon and creating a model which helps us to predict the behavior of the system under study. Just because we have a model does not mean that is how the system actually works.

As the saying goes, "Man plans. God laughs."

Thank you for your answer, my one is a provocation. I agree with you. But I wanted to see some different opinions from different people. We all know about this new experiment on neutrinos that seemed to go faster than the light and now they say they made probably wrong measures. Also, when I say wrong, I say, maybe is there something else we did not see that goes really faster than the light or this is really a final cut? However let's God or Gods continue/s smiling, but we are going deeper at least, even if we are "monkeys with special shocks on a brain".

I think there needs to be some tweaks in Relativity to account for hawking radiation and quantum effects and free will but the basic math is correct with how we expereince things on macro scale.

Jimmy, I like your idea or rather way of explaining these issues...thanks

I agree Prakash Kumar.

Yes, otherwise everything would be wrong now ;)

I would like to add, that in Physics we have no "right" or "wrong" theories. All we have are models of a given class of phenomena, and these models are RIGHT WITH KNOWN PRECISION! Increasing the precision, or changing the domain of application, we are discovering the need to change somehow the model - to put it in correspondence with the reality with a NEW PRECISION. This does not mean that the old model is wrong. This way we simply are starting to understand the precise domain of application of the old model. The Newton mechanics is the best example.

Hi Plamen

Your last comment reminds me of H&M's Model Dependent Realism.

Hi Graham,

It simply reflects the REALITY in Physics and in serious Science. I do not think that one has to pay attention to other point of views on this fundamental topic. Of course, if he is working in Science, not in philosophy or other branches of human knowledge. Sorry, if some people do not like this.

I am afraid I look too much at the big picture.

Questions like: Can we have a complete theory?

I like to see my science actually model new things.

I like my philosophy to handle the deepest questions.

I am not a fan of putting different labels on stuff and presenting it as new knowlege.

I became a fan of Hawking after reading The Grand Design.

There were many ideas in the book that I had already been thinking through and writing about.

I figured if we were thinking through many of the same ideas, he must be OK.

General Relativity (GR) is our best model of gravitation. It fails to describe the rotation of galaxies and the attraction between galaxies in local groups. In order to explain these gravitational phenomena within GR framework we had to assume the existence of dark matter. General Relativity predicts the expansion of the Universe at a constant rate. Ten years ago we found out that the expansion is accelerating. To explain this phenomena within GR we assumed the existence of dark energy. So far we have found no experimental evidences of dark matter! We keep looking! It is also known that quantum mechanic is incompatible in fundamental ways with GR and most physicists think that it will be eventually replaced by a quantum gravity theory. A lot of theoretical work in done in order to eventually build a quantum gravity theory but we are only at the stage of digging the fondations. For now we are stuck at fixing the old car as best as we can!

What theory? GR fits to the observed and allows more measurements. The new theories will pretend to be adjusted also to the observed, and so history is written. Wrong? Better, incomplete, or a beginning that all we use, etc.

Why this constant question?

It is not wrong but Incomplete. To our bad fortune we do not have a thinker better then Einstein.

It is not wrong but Incomplete. To our bad fortune we do not have a thinker better then Einstein. Even if, we get a thinker, the politics at global level is so high that by chance if they realise incompetency of

Einstein-theory, big and famous personalities are never ready to

accept at cost of their Name, Fame and doubtlessly money.

I think that Einstein theory of relativity (as any theory) can not be said to be right or wrong, from a scientific point of view. From this point of view we can only say that so far it is a valid theory, valid until a "reasonable" amount of experimental evidence contradicts it.To day there is no such evidence.

The physics that we know today can only account of 5% of the universe.95% of the universe is unaccounted for!It makes you wounder how much physics we know?

Einstien's STR can't be right and incomplete at the same time!

If Godelian Incompleteness applies to real as well as virtual worlds then the universe itself may be incomplete or any models of it either incomplete or self contradictory.

The theory is good enough to solve most problems, and give the correct answers. That makes it correct in those domains. If you take it to extreme enough domains, it breaks down, so is incomplete. It might be analagous to saying division works fine, except in extreme cases when you divide by zero, so it's incomplete there.

So, it is not a question of right or wrong, it is a question of complete or incomplete.Clearly the answer is incomplete.

Well, I think that all theories are complete within its conditioned field of application. Conditioned to a certain acceptable aproximation, and this is given by the precision of the measurement instrumentation. Newton´s laws are ok until we require more approximation ( and have available appropiate instruments of measurement). Outside this, Newton´s laws are not valid, and therefore incomplete. Then we have SRT that is valid all the way (with no gravitation, therefore incomplete) in all range of speeds. If we introduce gravitation into account, again SRT is not valid all the way: so far the valid one is General Relativity Theory. This theory is equivalent to Newton´s for small speeds compared with the speed of light. It is also equivalent to the STR all the way of speeds (with negligible gravitation). This is being validated as of today. The problem is that it is a continous variable approach and it does not contemplate quanta. In this sense I think GRT is incomplete. On the other hand relativistic quantum mechanics theory has no gravitation. We still need a theory of relativistic quantum mechanics that also contemplates gravitation. That would appear as a complete theory. However it still would need validation, say from time to time.

By definition any physical theory is “wrong” in some sense just because it is based on abstract mathematical concepts which inevitably neglects many aspects of reality. So general relativity presents a geometrical model of gravity phenomenon which has been tested in some finite range its parameters. GR is a good theory but it is not an ultimate theory of gravitation.

More important question is how and where the border of applicability of GR can be found.

To answer this question one should consider an alternative gravitation theory which easily explains existing really tested experimental facts and predicts new crucial effects which can distinct between GR and the new theory. Here it is important to consider new type of experiments which were not tested in GR.

For example such natural physical theory of gravitation is the tensor relativistic quantum field approach which consider gravitation force as the result of the universal interaction with matter via the symmetric second rank material field F_ik , where all really tested relativistic gravity effects also exist (e.g. arXiv: 0809.2323). Here crucial experiments/observations are: the free fall of rotating bodies, the sum of the tensor (spin 2) and scalar (spin 0) fields included in the gravity force, additional scalar gravitational waves from collapsing stars, compact massive relativistic objects with surface and magnetic field, gravitational cosmological redshift in cosmology.

These tests will be performed in near future thanks to development of modern technology.

Regarding the rotational characteristics of galaxies as a failure of GR gravity, it's my understanding that the failure is a result of improperly representing the mass distribution of compound objects. As an information systems analyst I find that the galaxy rotation problem was the product of an invalid assumption - that Keplerian relations should apply to vast distributions of self-gravitating masses.

I cannot fully asses the physics or mathematics involved, but I am aware of one research report that seems to successfully apply unmodified GR gravitation to explain the observed rotational characteristics of spiral galaxies without dark matter:

J. D. Carrick and F. I. Cooperstock. "General relativistic dynamics applied to the rotation curves of galaxies." Astrophysics and Space Science. 337 1 (2012): 321-329. http://dx.doi.org/10.1007/s10509-011-0854-z.

GR has also been applied to an intrinsically dynamic free-fall model representing an idealized Coma Cluster of galaxies in:

F. I. Cooperstock and S. Tieu (2008). "General relativistic velocity: the alternative to dark matter". Modern Physical Letters A. 23 (2008): 1745-1755. http://dx.doi.org/10.1142/S0217732308027163 http://arxiv.org/abs/0712.0019v1

While these authors consider that the reason their models succeed where others fail to explain the observed 'flat' rotation curve of spiral galaxies is the inherent superiority of GR gravitation over Newtonian methods, I think the critical issue is proper representation of disk mass distribution and gravitation. Some others have successfully applied classical dynamics to the disk rotation problem:

James Q. Feng and C. F. Gallo. "Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies." Res. Astron. Astrophys. 11 (Dec. 2011): 1429. http://dx.doi.org/10.1088/1674-4527/11/12/005 http://arxiv.org/abs/1104.3236v4

ChrisPappas mentioned Godelian Incompleteness.

I have a hunch that Godelian Incompleteness (or something simialr) does apply to physical realities, but if so such realities may prove to be unreal.

Model Dependent Realism tries to sidestep this problem by allowing inconsistent theories which are all possibly true in constrained situations. Roger Penrose seems to points out that the total systems of everything may have to be contradictory. See his youtube on cohomology. Google "youtube penrose cohomology" or find the link on benjibear.com.

Grahm Partis - good point, at least to the extent that I understand. Useful models may not fully represent physical processes contributing to predicted results. As I understand, GR's 'curvature' of spacetime only describes the effects of gravitation in abstract geometric terms, not really any physical elements and process producing those effects. IMO, gravitational effects producing the acceleration of physical objects can be described in terms of abstract dimensional coordinates, but those geometric coordinates cannot produce physical motion. While mathematicians may be satisfied and the effects of gravitation very accurately predicted, I think there is a physical aspect of gravitation that has not yet been described.

I suspect that gravitation may be physically produced by kinetic vacuum energy, directed and condensed by the accretion of matter, evidenced by quantum fluctuations - the very real emissions of virtual particle/antiparticle annihilations. In that case the rate of quantum fluctuations must vary correspondingly with gravitational effects, as a function of altitude on Earth or Earth orbit, or on the lunar surface, for example.

In that case GR's geometry of spacetime physically represents directional gradients of vacuum energy density. The attractive force described by Newton's quite useful universal law of gravitation may represent the intersection of opposingly directed gradient fields of vacuum energy density surrounding two objects. All speculative, of course - merely a reference design for a physical system producing the effects of gravity.

RE: "I suspect that gravitation may be physically produced by kinetic vacuum energy, directed and condensed by the accretion of matter, evidenced by quantum fluctuations - the very real emissions of virtual particle/antiparticle annihilations"

I suspect virtual particles/antiparticles arise and associated fluctuations arise out of rounding effects (or "rounding errors"). Such effects could result from a projection from a digital Virtualism or similar information theory or via projection from an analog ( or more precise) 4D (or higher) continuum projected onto our quantized (digital?) 3D world in time.

How would your kinetic vacuum idea fit in such scenarios?

I think it would fit well but I never thought of an explanation of gravity arising from quantum fluctuations.

Maybe your idea fits better with something like quantum dynamics; or thermodynamic versions of holographic information theories.

Graham Partis,

I'm merely speculating, of course, but I think the notion of a predictive theory that attributes physical effects to curvatures inexplicably imparted to a geometry of dimensional spacetime is incomplete, no matter how useful and accurate its predictions are. I think the described curvature must actually represent some very physical aspect of spacetime.

I also think the expansion of spacetime must also have initially been initially imparted by some energy not imparted to disperse matter or objects of mass but contained within the 'vacuum' of spacetime.

I do not think that physical effects are caused by any theories, but that physics theories are intended to describe physical phenomena. While quantum theory may consider that the vacuum contains no energy or matter, I suggest that this should be experimentally determined. As I understand, the effects of vacuum energy can be experimentally observed in various phenomena. See http://en.wikipedia.org/wiki/Vacuum_energy

This idea could be tested by measuring vacuum energy density (perhaps as quantum fluctuations over time) with a sufficiently sensitive apparatus so that any variation might be correlated with the local effects of gravitation.

I don't think that gravitation (or expansion) is caused by quantum fluctuations per se, but that they are all effects caused by energy contained within spacetime. I suspect that the process of accretion of matter involves both the local condensation of matter and its extraction from a region of space. The process might be an interaction in which vacuum energy was also redirected towards the then condensed location of potential mass-energy. Increasing the amount of locally condensed matter requires its extraction from spacetime, redirecting and locally contracting local vacuum energy density.

Gradient fields of physical vacuum energy might accurately be represented by the curvature of spacetime geometry described by GR through the abstract dimensional coordinates of spacetime.

This view of gravitation might also explain why it seems to be 'weaker' than other forces of matter, despite having unlimited range. In this scenario gravitation is not strictly a property of matter, although it is an interaction with material mass-energy. This could also help explain why gravity is so difficult (or impossible) to integrate with the standard model of particle physics - it is not strictly a particle mediated quantum interaction.

I'm not a physicist and unfortunately cannot further evaluate or develop these ideas. If correct, they would provide a physical mechanism that produces gravitation, as described by GR, and perhaps resolve the apparent discrepancy between GR and quantum mechanics. My intent was merely to identify a potential physical basis for gravitation.

Dear All, 

I wrote repeatedly that, in my opinion, the model that underlies the GR is physically doubtful as applied to Universe and, therefore, the applicability of its resulted combined equations for any explanations or predictions of phenomena out of the Solar System is under question. Below, I explain my opinion.

According to the GR, light propagates over Space in straight lines and with the constant speed. Meanwhile, it is well known that light interacts with gravitation fields (GFs) and deviates in them from straight lines. Apparently, there are no doubts that each stellar system has its own gravitational potential (GP) and each galaxy has its own mean GP. Mathematically, it is possible to take approximately that the GFs are localized. However, physically, GFs are infinite. Thus, Space is under an effect of a sum of more or less weak GFs and, apparently, is gravitationally heterogeneous. If it is so, light should propagate over Space in nonstraight lines and with nonconstant linear speeds. Indeed, the GFs are weak over the major portion of Space; however, the distances are great and the total effects of gravitation may be significant. I saw discussion of this question in the literature.