Why Theoretical Physicists Produce Models
(trop ancien pour répondre)
Pentcho Valev
2017-06-03 08:44:13 UTC
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Theoretical physicists produce models "literally because they can make money with it":

Sabine Hossenfelder: "The problem that nobody seems to want to talk about is that rather than trying to find a minimal model that explains the data and leave it at this, there are many hundreds of models for inflation all of which are almost certainly wrong because they contain too many details that aren't supported by data. As the philosophers have it, these models are severely underdetermined. Theoretical physicists produce these models literally because they can make money with it. They make money with it by getting them published and then using the publications to claim it's relevant research so it'll get funded and they can hire more postdocs to crunch out more papers. It's the same reason why theorists invent dark matter particles and extensions of the standard model. It's a way to make a living." http://www.math.columbia.edu/~woit/wordpress/?p=9349

Theoretical physicists' models are not deductive constructions. Just like the prototype, Einstein's general relativity, they are not-even-wrong empirical concoctions able to predict anything because their parameters can be tweaked "in seemingly endless ways":

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."

"So what about the second criticism, that inflation is too flexible to be tested? It's true that while the idea behind inflation is simple, its parameters can be tweaked in seemingly endless ways... [...] In other words, the critics say, go out and measure almost anything and someone will say, "hey, that's evidence for inflation." Theories that can predict anything predict nothing. Inflation, they say, isn't science." http://nautil.us/issue/48/chaos/the-inflated-debate-over-cosmic-inflation

For instance, 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):

"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." https://www.newscientist.com/article/2116446-first-test-of-rival-to-einsteins-gravity-kills-off-dark-matter/

Pentcho Valev
Pentcho Valev
2017-06-03 12:58:52 UTC
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Essentially, theoretical physicists' models are equivalent to the "empirical models" defined here:

"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."

Not all theoretical physicists make good money with their empirical models - only the silliest and most immoral ones are eligible. For instance, Sabine Hossenfelder will never become a millionaire and her future as a theoretical physicist is quite uncertain:

Sabine Hossenfelder: "As light carries energy and is thus subject of gravitational attraction, a ray of light passing by a massive body should be slightly bent towards it. This is so both in Newton's theory of gravity and in Einstein's, but Einstein's deflection is by a factor two larger than Newton's. [...] As history has it, Eddington's original data actually wasn't good enough to make that claim with certainty. His measurements had huge error bars due to bad weather and he also might have cherry-picked his data because he liked Einstein's theory a little too much. Shame on him."

Hossenfelder's crime above is not so much the attack against Eddington - that he was a fraudster is not a secret, even among faithful Einsteinians. Hossenfelder's unforgivable crime is that she informs the brainwashed world that Newton's theory also predicts deflection. This is dangerous - the 1919 measurement of the extremely small deflection is already highly suspicious, let alone measurement of the difference between two extremely small deflections.

Kip Thorne is different from Sabine Hossenfelder - without any hesitation he informs the brainwashed world that Newton's theory predicts NO DEFLECTION:

Kip Thorne: "A second crucial proof of the breakdown in Newtonian gravity was the relativistic bending of light. Einstein's theory predicted that starlight passing near the limb of the sun should be deflected by 1.75 seconds of arc, whereas NEWTON'S LAW PREDICTED NO DEFLECTION. Observations during the 1919 eclipse of the sun in Brazil, carried out by Sir Arthur Eddington and his British colleagues, brilliantly confirmed Einstein's prediction to an accuracy of about 20 percent. This dealt the final death blow to Newton's law and to most other relativistic theories of gravity."

Accordingly, Kip Thorne is eligible for becoming a millionaire:

"Nine scientists just won an award that's worth more than a Nobel Prize, earning a cool $1 million for their cutting-edge research. Called the Kavli Prize, these lofty awards... [...] The three winners in astrophysics this year were Ronald Drever, Kip Thorne, and Rainer Weiss. The trio won for detecting the ripples in space-time known as gravitational waves — arguably the most remarkable scientific achievement of the year, if not the past 100 years. "This detection has, in a single stroke and for the first time, validated Einstein’s General Theory of Relativity for very strong fields..."

"Weiss will share the $1.2 million prize with Kip Thorne, Caltech’s Richard P. Feynman Professor of Theoretical Physics, emeritus; and Ronald Drever, emeritus professor of physics at Caltech. Together, they are cited by the Shaw Foundation “for conceiving and designing the Laser Interferometer Gravitational-Wave Observatory (LIGO), whose recent direct detection of gravitational waves opens a new window..."

"LIGO Gravitational Wave Researchers to Divide $3 Million. The three ringleaders of the gravitational-wave experiment, known as LIGO, Ronald P. Drever and Kip. S. Thorne of the California Institute of Technology, and Rainer Weiss of the Massachusetts Institute of Technology, will split $1 million. The other $2 million will be split among 1,012 scientists who were authors of the article in Physical Review Letters, or who made major contributions to the study of gravitational waves."

"In addition to a cash award of $500 000, to be shared equally between Drever, Thorne and Weiss, each of the three will receive a gold medal and a citation that reads: The Gruber Foundation proudly presents the 2016 Cosmology Prize to Rainer Weiss, Kip Thorne, Ronald Drever, and the entire LIGO team for pursuing a vision to observe the universe in gravitational waves, leading to a first detection that emanated from the collision of two black holes."

Pentcho Valev
Pentcho Valev
2017-06-04 08:24:25 UTC
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Sabine Hossenfelder: "The value of the cosmological constant is infamously the worst prediction ever made using quantum field theory; the math says it should be 120 orders of magnitude larger than what we observe. But that the cosmological constant has a small, non-zero value that causes the Universe to accelerate is extremely well established by measurement. The evidence is so thoroughly robust that a Nobel Prize was awarded for its discovery in 2011. Exactly what the value of the cosmological constant is, though, is controversial. There are different ways to measure the cosmological constant, and physicists have known for a few years that the different measurements give different results. This tension in the data is difficult to explain, and it has so-far remained unresolved." https://www.forbes.com/sites/startswithabang/2017/05/30/is-there-really-a-cosmological-constant-or-is-dark-energy-changing-with-time/

The mere possibility that a fudge factor not deduced from postulates CAN be introduced proves that the respective model (Einstein's general relativity) is an empirical concoction (not even wrong):

"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..."

"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."

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

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