Discussion:
Deductive and Non-Deductive (Not-Even-Wrong) Theories in Physics
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Pentcho Valev
2017-05-21 06:52:44 UTC
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My long-standing efforts to convince physicists that DEDUCTION is the only reasonable method in theoretical physics (without deduction the "theories" produced are not even wrong) have finally paid off:

Lubos Motl: "Quantum mechanics is another example of deductive reasoning. [...] Only the implications "IF... THEN..." are guaranteed to hold according to the quantum mechanical laws of physics." http://motls.blogspot.bg/2017/05/quantum-mechanics-is-another-example-of.html

Motl is avoiding any mentioning of Einstein's relativity - he now knows that general relativity is not deductive. And the only alternative to deductive theory is empirical (in the sense defined by Einstein below) concoction - a "theory" that is not even wrong and is therefore unfalsifiable. Einstein clearly explains the difference between deduction and empirical approach here:

https://www.marxists.org/reference/archive/einstein/works/1910s/relative/ap03.htm
Albert Einstein: "From a systematic theoretical point of view, we may imagine the process of evolution of an empirical science to be a continuous process of induction. Theories are evolved and are expressed in short compass as statements of a large number of individual observations in the form of empirical laws, from which the general laws can be ascertained by comparison. Regarded in this way, the development of a science bears some resemblance to the compilation of a classified catalogue. It is, as it were, a purely empirical enterprise. But this point of view by no means embraces the whole of the actual process ; for it slurs over the important part played by intuition and deductive thought in the development of an exact science. As soon as a science has emerged from its initial stages, theoretical advances are no longer achieved merely by a process of arrangement. Guided by empirical data, the investigator rather develops a system of thought which, in general, is built up logically from a small number of fundamental assumptions, the so-called axioms."

Special relativity was indeed "built up logically from a small number of fundamental assumptions", that is, it was deductive (even though a false postulate and an invalid argument spoiled it from the very beginning), but general relativity was, to use Einstein's words, "a purely empirical enterprise". Einstein and his mathematical friends changed and fudged equations countless times until "a classified catalogue" was compiled where known in advance results and pet assumptions (such as the Mercury's precession, the equivalence principle, gravitational time dilation) coexisted in an apparently consistent manner. Being an empirical concoction, general relativity allows Einsteinians to introduce, change and withdraw fudge factors until the "theory" manages to predict anything Einsteinians want. Then the prediction turns out to be confirmed by observations (surprise surprise).

So, as far as the unfalsifiability problem in theoretical physics is concerned, THE ROOT OF THE MALIGNANCY IS GENERAL RELATIVITY. Here are the metastases:

"Almost 40 years after their inception, inflation and string theory are in worse shape than ever. The persistence of these unfalsifiable and hence unscientific theories is an embarrassment that risks damaging science's reputation at a time when science can ill afford it. Isn't it time to pull the plug?" https://blogs.scientificamerican.com/cross-check/is-a-popular-theory-of-cosmic-creation-pseudoscience/

"This year, debates in physics circles took a worrying turn. Faced with difficulties in applying fundamental theories to the observed Universe, some researchers called for a change in how theoretical physics is done. They began to argue - explicitly - that if a theory is sufficiently elegant and explanatory, it need not be tested experimentally, breaking with centuries of philosophical tradition of defining scientific knowledge as empirical." http://www.nature.com/news/scientific-method-defend-the-integrity-of-physics-1.16535

"Do physicists need empirical evidence to confirm their theories? You may think that the answer is an obvious yes, experimental confirmation being the very heart of science. But a growing controversy at the frontiers of physics and cosmology suggests that the situation is not so simple. [...] ...a mounting concern in fundamental physics: Today, our most ambitious science can seem at odds with the empirical methodology that has historically given the field its credibility." http://www.nytimes.com/2015/06/07/opinion/a-crisis-at-the-edge-of-physics.html

"In recent years, however, many physicists have developed theories of great mathematical elegance, but which are beyond the reach of empirical falsification, even in principle. The uncomfortable question that arises is whether they can still be regarded as science. Some scientists are proposing that the definition of what is "scientific" be loosened, while others fear that to do so could open the door for pseudo-scientists or charlatans to mislead the public and claim equal space for their views." http://www.prospectmagazine.co.uk/features/what-happens-when-we-cant-test-scientific-theories

The fudge-factor activity is inglorious and Einsteinians don't discuss it openly, but sometimes the truth comes out inadvertently. So conventional dark matter models based on general relativity "need four free parameters to be adjusted to explain the data" (how many fudge factors LIGO conspirators needed in order to model the nonexistent gravitational waves is a deep mystery):

https://www.newscientist.com/article/2116446-first-test-of-rival-to-einsteins-gravity-kills-off-dark-matter/
"Verlinde's calculations fit the new study's observations without resorting to free parameters – essentially values that can be tweaked at will to make theory and observation match. By contrast, says Brouwer, conventional dark matter models need four free parameters to be adjusted to explain the data."

Being an empirical concoction, Einstein's general relativity has no postulates:

https://www.quora.com/What-are-the-postulates-of-General-Relativity
What are the postulates of General Relativity? Alexander Poltorak, Adjunct Professor of Physics at the CCNY: "In 2005 I started writing a paper, "The Four Cornerstones of General Relativity on which it doesn't Rest." Unfortunately, I never had a chance to finish it. The idea behind that unfinished article was this: there are four principles that are often described as "postulates" of General Relativity:

1. Principle of general relativity

2. Principle of general covariance

3. Equivalence principle

4. Mach principle

The truth is, however, that General Relativity is not really based on any of these "postulates" although, without a doubt, they played important heuristic roles in the development of the theory." [end of quotation]

Essentially, general relativity is equivalent to the "empirical models" defined here (that is, it is as much a theory as they are):

http://collum.chem.cornell.edu/documents/Intro_Curve_Fitting.pdf
"The objective of curve fitting is to theoretically describe experimental data with a model (function or equation) and to find the parameters associated with this model. Models of primary importance to us are mechanistic models. Mechanistic models are specifically formulated to provide insight into a chemical, biological, or physical process that is thought to govern the phenomenon under study. Parameters derived from mechanistic models are quantitative estimates of real system properties (rate constants, dissociation constants, catalytic velocities etc.). It is important to distinguish mechanistic models from empirical models that are mathematical functions formulated to fit a particular curve but whose parameters do not necessarily correspond to a biological, chemical or physical property."

Here Michel Janssen describes the anti-deductive approach of Einstein and his mathematical friends - endlessly adjusting the model until "excellent agreement with observation" is reached:

https://netfiles.umn.edu/users/janss011/home%20page/EBms.pdf
Michel Janssen: "But - as we know from a letter to his friend Conrad Habicht of December 24, 1907 - one of the goals that Einstein set himself early on, was to use his new theory of gravity, whatever it might turn out to be, to explain the discrepancy between the observed motion of the perihelion of the planet Mercury and the motion predicted on the basis of Newtonian gravitational theory. [...] The Einstein-Grossmann theory - also known as the "Entwurf" ("outline") theory after the title of Einstein and Grossmann's paper - is, in fact, already very close to the version of general relativity published in November 1915 and constitutes an enormous advance over Einstein's first attempt at a generalized theory of relativity and theory of gravitation published in 1912. The crucial breakthrough had been that Einstein had recognized that the gravitational field - or, as we would now say, the inertio-gravitational field - should not be described by a variable speed of light as he had attempted in 1912, but by the so-called metric tensor field. The metric tensor is a mathematical object of 16 components, 10 of which independent, that characterizes the geometry of space and time. In this way, gravity is no longer a force in space and time, but part of the fabric of space and time itself: gravity is part of the inertio-gravitational field. Einstein had turned to Grossmann for help with the difficult and unfamiliar mathematics needed to formulate a theory along these lines. [...] Einstein did not give up the Einstein-Grossmann theory once he had established that it could not fully explain the Mercury anomaly. He continued to work on the theory and never even mentioned the disappointing result of his work with Besso in print. So Einstein did not do what the influential philosopher Sir Karl Popper claimed all good scientists do: once they have found an empirical refutation of their theory, they abandon that theory and go back to the drawing board. [...] On November 4, 1915, he presented a paper to the Berlin Academy officially retracting the Einstein-Grossmann equations and replacing them with new ones. On November 11, a short addendum to this paper followed, once again changing his field equations. A week later, on November 18, Einstein presented the paper containing his celebrated explanation of the perihelion motion of Mercury on the basis of this new theory. Another week later he changed the field equations once more. These are the equations still used today. This last change did not affect the result for the perihelion of Mercury. Besso is not acknowledged in Einstein's paper on the perihelion problem. Apparently, Besso's help with this technical problem had not been as valuable to Einstein as his role as sounding board that had earned Besso the famous acknowledgment in the special relativity paper of 1905. Still, an acknowledgment would have been appropriate. After all, what Einstein had done that week in November, was simply to redo the calculation he had done with Besso in June 1913, using his new field equations instead of the Einstein-Grossmann equations. It is not hard to imagine Einstein's excitement when he inserted the numbers for Mercury into the new expression he found and the result was 43", in excellent agreement with observation."

Pentcho Valev
Pentcho Valev
2017-05-21 10:43:55 UTC
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In order to make general relativity's equations agree with both the nonexistent gravitational time dilation and the gravitational redshift, Einstein and his mathematical friends introduced a particularly idiotic fudge factor: The speed of light falling towards the source of gravity DECREASES - in the gravitational field of the Earth the acceleration of falling photons is NEGATIVE, -2g:

https://archive.is/wn4PV
Albert Einstein: "Second, this consequence shows that the law of the constancy of the speed of light no longer holds, according to the general theory of relativity, in spaces that have gravitational fields. As a simple geometric consideration shows, the curvature of light rays occurs only in spaces where the speed of light is spatially variable."


"The change in speed of light with change in height is dc/dh=g/c."

http://www.physlink.com/Education/AskExperts/ae13.cfm
"Contrary to intuition, the speed of light (properly defined) decreases as the black hole is approached."

http://www.speed-light.info/speed_of_light_variable.htm
"Einstein wrote this paper in 1911 in German. [...] ...you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+φ/c^2) where φ is the gravitational potential relative to the point where the speed of light c0 is measured. Simply put: Light appears to travel slower in stronger gravitational fields (near bigger mass). [...] You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak field approximation. [...] Namely the 1955 approximation shows a variation in km/sec twice as much as first predicted in 1911."

http://www.mathpages.com/rr/s6-01/6-01.htm
"Specifically, Einstein wrote in 1911 that the speed of light at a place with the gravitational potential φ would be c(1+φ/c^2), where c is the nominal speed of light in the absence of gravity. In geometrical units we define c=1, so Einstein's 1911 formula can be written simply as c'=1+φ. However, this formula for the speed of light (not to mention this whole approach to gravity) turned out to be incorrect, as Einstein realized during the years leading up to 1915 and the completion of the general theory. [...] ...we have c_r =1+2φ, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term."

The speed of light does vary in a gravitational field but not in accordance with Einstein's fudge factor. It varies like the speed of ordinary falling bodies (in the gravitational field of the Earth the acceleration of falling photons is g), as predicted by Newton's emission theory of light:

"If we accept the principle of equivalence, we must also accept that light falls in a gravitational field with the same acceleration as material bodies." http://sethi.lamar.edu/bahrim-cristian/Courses/PHYS4480/4480-PROBLEMS/optics-gravit-lens_PPT.pdf

Gravitational time dilation does not exist - the gravitational redshift is caused by the variation of the speed of light predicted by Newton's emission theory of light:

https://courses.physics.illinois.edu/phys419/sp2011/lectures/Lecture13/L13r.html
University of Illinois at Urbana-Champaign: "Consider a falling object. ITS SPEED INCREASES AS IT IS FALLING. Hence, if we were to associate a frequency with that object the frequency should increase accordingly as it falls to earth. Because of the equivalence between gravitational and inertial mass, WE SHOULD OBSERVE THE SAME EFFECT FOR LIGHT. So lets shine a light beam from the top of a very tall building. If we can measure the frequency shift as the light beam descends the building, we should be able to discern how gravity affects a falling light beam. This was done by Pound and Rebka in 1960. They shone a light from the top of the Jefferson tower at Harvard and measured the frequency shift. The frequency shift was tiny but in agreement with the theoretical prediction. Consider a light beam that is travelling away from a gravitational field. Its frequency should shift to lower values. This is known as the gravitational red shift of light."

http://www.einstein-online.info/spotlights/redshift_white_dwarfs
Albert Einstein Institute: "One of the three classical tests for general relativity is the gravitational redshift of light or other forms of electromagnetic radiation. However, in contrast to the other two tests - the gravitational deflection of light and the relativistic perihelion shift -, you do not need general relativity to derive the correct prediction for the gravitational redshift. A combination of Newtonian gravity, a particle theory of light, and the weak equivalence principle (gravitating mass equals inertial mass) suffices. [...] The gravitational redshift was first measured on earth in 1960-65 by Pound, Rebka, and Snider at Harvard University..."

Pound, Rebka and Snider knew that their experiments had confirmed the variation of the speed of light predicted by Newton's emission theory of light, not the gravitational time dilation predicted by Einstein's relativity:

http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.4.337
R. V. Pound and G. A. Rebka, Jr, APPARENT WEIGHT OF PHOTONS

http://virgo.lal.in2p3.fr/NPAC/relativite_fichiers/pound.pdf
R. V. Pound and J. L. Snider, Effect of Gravity on Gamma Radiation: "It is not our purpose here to enter into the many-sided discussion of the relationship between the effect under study and general relativity or energy conservation. It is to be noted that no strictly relativistic concepts are involved and the description of the effect as an "apparent weight" of photons is suggestive. The velocity difference predicted is identical to that which a material object would acquire in free fall for a time equal to the time of flight."

Pentcho Valev
Pentcho Valev
2017-05-22 08:08:23 UTC
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"Einstein's equations of general relativity that describe the expansion of the universe are so complex mathematically, that for a hundred years no solutions accounting for the effect of cosmic structures have been found. We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein's equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data." explains Dr László Dobos, co-author of the paper, also at Eötvös Loránd University."
http://www.science20.com/news_staff/accelerating_universe_expansion_without_a_need_to_invoke_magical_dark_energy-225024

Have Einstein's equations of general relativity been deduced from "a small number of fundamental assumptions, the so-called axioms", Einsteinians? In other words, is general relativity deductive? If not, is it an empirical concoction (not even wrong)? Do you care?

More anti-deductivism:

"A fudge factor is an ad hoc quantity introduced into a calculation, formula or model in order to make it fit observations or expectations. Examples include Einstein's Cosmological Constant..."
https://en.wikipedia.org/wiki/Fudge_factor

"In 1916 Einstein found what he considered a glitch in his new theory of general relativity. His equations showed that the contents of the universe should be moving - either expanding or contracting. But at the time, the universe seemed the very definition of stasis. All the data, facts, and phenomena known in the early 1900s said that the Milky Way was the cosmos itself and that its stars moved slowly, if at all. Einstein had presented the definitive version of the general theory of relativity to the Prussian Academy of Sciences the previous year, and he was not inclined to retract it. So he invented a fudge factor, called lambda, that could function mathematically to hold the universe at a standstill. [...] Lambda, also known as the cosmological constant, has come in handy of late."
http://discovermagazine.com/2004/sep/the-masters-mistakes/

Ken Croswell, Magnificent Universe, p. 179: "Ever since, the cosmological constant has lived in infamy, a fudge factor concocted merely to make theory agree with observation." http://www.amazon.com/Magnificent-Universe-Ken-Croswell/dp/0684845946

Can one introduce a fudge factor analogous to the cosmological constant in the Lorentz transformation equations? One cannot, and the reason is simple: Special relativity is DEDUCTIVE (even though a false postulate and an invalid argument spoiled it from the very beginning) and fudging is impossible by definition (one has no right to introduce anything that is not deducible from the postulates).

The "accepted" anti-deductive practice:

Sabine Hossenfelder: "Many of my colleagues believe this forest of theories will eventually be chopped down by data. But in the foundations of physics it has become extremely rare for any model to be ruled out. The accepted practice is instead to adjust the model so that it continues to agree with the lack of empirical support."
http://www.nature.com.proxy.readcube.com/nphys/journal/v13/n4/full/nphys4079.html

Pentcho Valev

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