Discussion:
String Theory: the Final Mutant of Post-Truth Science
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Pentcho Valev
2017-12-23 10:22:43 UTC
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Peter Woit: “This Week’s Hype: The Best Explanation for Everything in the Universe. Today The Atlantic has, via Quanta Magazine, some unadulterated, pure, grade A hype for the holidays: String Theory: The Best Explanation for Everything in the Universe. In a time when the credibility of science is under attack, does anyone else see a problem with telling the public that the “Best Explanation for Everything in the Universe” that science has is a “theory” for which we have no definition or equations, no experimental evidence, and no likelihood of ever getting any?” http://www.math.columbia.edu/~woit/wordpress/?p=9894

String theory is only the tip of the iceberg:

Sabine Hossenfelder (Bee): "The criticism you raise that there are lots of speculative models that have no known relevance for the description of nature has very little to do with string theory but is a general disease of the research area. Lots of theorists produce lots of models that have no chance of ever being tested or ruled out because that's how they earn a living. The smaller the probability of the model being ruled out in their lifetime, the better. It's basic economics. Survival of the 'fittest' resulting in the natural selection of invincible models that can forever be amended." http://www.math.columbia.edu/~woit/wordpress/?p=9375

The “general disease” can be called empirical theorising. Einstein’s text below suggests that a physics theory is either a not-even-wrong empirical concoction or a deductive construction "built up logically from a small number of fundamental assumptions, the so-called axioms":

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." https://www.marxists.org/reference/archive/einstein/works/1910s/relative/ap03.htm

In other words, equations in a physics theory are either guessed or (possibly guessed initially but then rigorously) deduced from "a small number of fundamental assumptions, the so-called axioms":

Richard Feynman: "Dirac discovered the correct laws for relativity quantum mechanics simply by guessing the equation. The method of guessing the equation seems to be a pretty effective way of guessing new laws." http://dillydust.com/The%20Character%20of%20Physical%20Law~tqw~_darksiderg.pdf

Except for special relativity which is deductive, theories and models in today's fundamental physics are empirical (“invincible models that can forever be amended”).

Pentcho Valev
Pentcho Valev
2017-12-23 14:26:36 UTC
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Einstein's general relativity was not deduced from "a small number of fundamental assumptions, the so-called axioms". It is a not-even-wrong empirical concoction - a malleable combination of ad hoc ("guessed") equations and fudge factors allowing Einsteinians to predict anything they want.

Before 1915 theoretical physics was mainly DEDUCTIVE - you cannot introduce any changes to your theory that are not deducible from the initial axioms (postulates). In 1915 things changed. Here Michel Janssen describes endless empirical groping, fudging and fitting until "excellent agreement with observation" was reached:

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." https://netfiles.umn.edu/users/janss011/home%20page/EBms.pdf

Pentcho Valev
Pentcho Valev
2017-12-25 17:13:44 UTC
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There are internal mavericks in Einstein cult who believe that nowadays bad Einsteinians ruin what good Einsteinians (Einstein, Eddington, Feynman) have created:

Peter Woit: "If, as seems increasingly all too possible, we're now at an endpoint of fundamental physics, with the field killed off by a pseudo-scientific argument..." http://www.math.columbia.edu/~woit/wordpress/?p=9444

Peter Woit: "I think the worst thing that has happened to theoretical physics over the past 25 years is this descent into ideology, something that has accelerated with the multiverse mania of the last 10-15 years." http://www.math.columbia.edu/~woit/wordpress/?p=9375

Peter Woit: "Many are worried about the status of science in our society, as it faces new challenges. I don't see how the physics community is going to continue to have any credibility with the rest of society if it sits back and allows multiverse mania to enter the canon. Non-scientists taking science classes need to be taught about the importance of always asking: what would it take to show that this theory is wrong? how do I know this is science not ideology?" http://www.math.columbia.edu/~woit/wordpress/?p=9469

Peter Woit: "As far as this stuff goes, we're now not only at John Horgan's "End of Science", but gone past it already and deep into something different." http://www.math.columbia.edu/~woit/wordpress/?p=7266

Peter Woit: "This all of a sudden made things clear: what is going on is "theatrical physics", not "theoretical physics"." http://www.math.columbia.edu/~woit/wordpress/?p=9691

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

Sabine Hossenfelder (Bee): "The criticism you raise that there are lots of speculative models that have no known relevance for the description of nature has very little to do with string theory but is a general disease of the research area. Lots of theorists produce lots of models that have no chance of ever being tested or ruled out because that's how they earn a living. The smaller the probability of the model being ruled out in their lifetime, the better. It's basic economics. Survival of the 'fittest' resulting in the natural selection of invincible models that can forever be amended." http://www.math.columbia.edu/~woit/wordpress/?p=9375

Sabine Hossenfelder: "The current situation in the foundations of physics is a vivid example for how science fails to self-correct. [...] I just meant to say I have debated back and forth with myself for a long time whether I should publicly denounce most of the research in my field as nonsense. It would have been easy enough to write a book about something else, you know, the usual science cheer leading stuff. But it's just not me." http://backreaction.blogspot.bg/2017/10/book-update.html

Of course, I'm sympathetic to Hossenfelder and Woit. However, being Einsteinians, they too will have to answer the "embarrassing question":

"This paper investigates an alternative possibility: that the critics were right and that the success of Einstein's theory in overcoming them was due to its strengths as an ideology rather than as a science. The clock paradox illustrates how relativity theory does indeed contain inconsistencies that make it scientifically problematic. These same inconsistencies, however, make the theory ideologically powerful. [...] The gatekeepers of professional physics in the universities and research institutes are disinclined to support or employ anyone who raises problems over the elementary inconsistencies of relativity. A winnowing out process has made it very difficult for critics of Einstein to achieve or maintain professional status. Relativists are then able to use the argument of authority to discredit these critics. Were relativists to admit that Einstein may have made a series of elementary logical errors, they would be faced with the embarrassing question of why this had not been noticed earlier. Under these circumstances the marginalisation of antirelativists, unjustified on scientific grounds, is eminently justifiable on grounds of realpolitik. Supporters of relativity theory have protected both the theory and their own reputations by shutting their opponents out of professional discourse. [...] The triumph of relativity theory represents the triumph of ideology not only in the profession of physics bur also in the philosophy of science." Peter Hayes, The Ideology of Relativity: The Case of the Clock Paradox http://www.informaworld.com/smpp/content~content=a909857880

Pentcho Valev

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