Aug 18, 2019 08:15 PM
https://www.sciencenews.org/blog/context...-plenitude
EXCERPT: Science, like baseball, has a lot of unwritten rules. [...] In science, the official rulebook consists of the laws of nature ... Science’s unwritten rules aren’t so strict. They are merely guidelines, suggestions for how best to play the game but without the totalitarian force of true natural law.
One such less-than-totalitarian principle is known as the … totalitarian principle. It is commonly expressed as “whatever is not forbidden is compulsory.” In other words, whatever the laws of nature allow must, in fact, exist or happen. That sounds a little bit like the opposite of totalitarianism, which would seem to require doing only what is compulsory, with everything else forbidden. And that’s just one of the confusions posed by the totalitarian principle discussed in a new paper by the historian Helge Kragh.
[...] Murray Gell-Mann first described the idea in 1956 ... Gell-Mann asserted that for some particles “any process which is not forbidden by a conservation law actually does take place.” He called it an assumption that “is related to the state of affairs that is said to prevail in a perfect totalitarian state. Anything that is not compulsory is forbidden.” Kragh doesn’t think Gell-Mann articulated the principle very clearly. For one thing, he was talking only about the strong force. And though he described his idea as related to totalitarianism, he had inverted the phrasing. ... subsequent physicists often attributed the principle to Gell-Mann and sometimes labeled it as totalitarian...
In any case, the underlying idea definitely did not originate with Gell-Mann. It rather descends from the philosophy of Plato, who believed that all possible ideal “forms” should actually exist in physical reality. In the 1930s, philosopher-historian Arthur Lovejoy referred to that idea as the “principle of plenitude” and discussed how it had been applied by other philosophers throughout history. But while the plenitude principle’s influence was widely recognized in biology, its use by physicists seems relatively recent. Kragh suggests that the totalitarian principle is in essence the successor of the plenitude principle “specially adapted to modern physics.”
One example of plenitude reasoning in physics (without naming it that) came from Paul Dirac [...] Dirac’s quantum equations seemed to allow particles with a single magnetic pole to exist, and so, he decided, they probably did. Subsequent searches have failed to find monopoles. But another hypothetical particle permitted by the laws of physics, the neutrino, did eventually turn up after nuclear reactors produced the particles copiously enough to enable their detection.
When Gell-Mann first mentioned the totalitarian principle, he recognized that depending on it posed a danger: [...] One, it suggests that if you discern that something is not forbidden, it’s a good idea to design an experiment to look for it. Two, if you look for it but don’t find it, then maybe that’s a sign that there’s some previously unknown law of nature that prevents it, and you should begin theoretical inquiries to look for the missing law. Kragh cites the discovery of baryon conservation in the 1950s as a consequence of failure to detect the decay of certain particles called baryons.
Similarly, failure to find magnetic monopoles led to investigations that produced the theory of cosmic inflation, the best current explanation of the early history of the universe. (Inflation indicates that monopoles very well could exist but that the rapid expansion of space in the early universe diluted their concentration so much that we would be unlikely to encounter one in our neighborhood today.)
In spite of such fruitful results from applying the totalitarian principle, it remains a mere guideline for scientific pursuits, not a guarantee of success. For one thing, it might not imply that anything that can exist does exist now — perhaps some possible things will come into existence only in the future. [...] You never really know for sure what’s possible and what isn’t. “What is considered physically or genuinely possible,” Kragh writes, “depends on the best scientific knowledge at any given time.” (MORE - details)
EXCERPT: Science, like baseball, has a lot of unwritten rules. [...] In science, the official rulebook consists of the laws of nature ... Science’s unwritten rules aren’t so strict. They are merely guidelines, suggestions for how best to play the game but without the totalitarian force of true natural law.
One such less-than-totalitarian principle is known as the … totalitarian principle. It is commonly expressed as “whatever is not forbidden is compulsory.” In other words, whatever the laws of nature allow must, in fact, exist or happen. That sounds a little bit like the opposite of totalitarianism, which would seem to require doing only what is compulsory, with everything else forbidden. And that’s just one of the confusions posed by the totalitarian principle discussed in a new paper by the historian Helge Kragh.
[...] Murray Gell-Mann first described the idea in 1956 ... Gell-Mann asserted that for some particles “any process which is not forbidden by a conservation law actually does take place.” He called it an assumption that “is related to the state of affairs that is said to prevail in a perfect totalitarian state. Anything that is not compulsory is forbidden.” Kragh doesn’t think Gell-Mann articulated the principle very clearly. For one thing, he was talking only about the strong force. And though he described his idea as related to totalitarianism, he had inverted the phrasing. ... subsequent physicists often attributed the principle to Gell-Mann and sometimes labeled it as totalitarian...
In any case, the underlying idea definitely did not originate with Gell-Mann. It rather descends from the philosophy of Plato, who believed that all possible ideal “forms” should actually exist in physical reality. In the 1930s, philosopher-historian Arthur Lovejoy referred to that idea as the “principle of plenitude” and discussed how it had been applied by other philosophers throughout history. But while the plenitude principle’s influence was widely recognized in biology, its use by physicists seems relatively recent. Kragh suggests that the totalitarian principle is in essence the successor of the plenitude principle “specially adapted to modern physics.”
One example of plenitude reasoning in physics (without naming it that) came from Paul Dirac [...] Dirac’s quantum equations seemed to allow particles with a single magnetic pole to exist, and so, he decided, they probably did. Subsequent searches have failed to find monopoles. But another hypothetical particle permitted by the laws of physics, the neutrino, did eventually turn up after nuclear reactors produced the particles copiously enough to enable their detection.
When Gell-Mann first mentioned the totalitarian principle, he recognized that depending on it posed a danger: [...] One, it suggests that if you discern that something is not forbidden, it’s a good idea to design an experiment to look for it. Two, if you look for it but don’t find it, then maybe that’s a sign that there’s some previously unknown law of nature that prevents it, and you should begin theoretical inquiries to look for the missing law. Kragh cites the discovery of baryon conservation in the 1950s as a consequence of failure to detect the decay of certain particles called baryons.
Similarly, failure to find magnetic monopoles led to investigations that produced the theory of cosmic inflation, the best current explanation of the early history of the universe. (Inflation indicates that monopoles very well could exist but that the rapid expansion of space in the early universe diluted their concentration so much that we would be unlikely to encounter one in our neighborhood today.)
In spite of such fruitful results from applying the totalitarian principle, it remains a mere guideline for scientific pursuits, not a guarantee of success. For one thing, it might not imply that anything that can exist does exist now — perhaps some possible things will come into existence only in the future. [...] You never really know for sure what’s possible and what isn’t. “What is considered physically or genuinely possible,” Kragh writes, “depends on the best scientific knowledge at any given time.” (MORE - details)