

AlexL
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AlexL last won the day on March 2
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Location
Fribourg, Switzerland
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Male
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Straight
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Alex Leibovici
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M.Sc. Physics
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Retired
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YouTube channel "1420", Daniil Orain, micro-interviews, mid-March 2023, in Moscow. Theme: "Do you think our government can stop this war at all?"
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Arrest Warrant for Putin - background and comments. Switch EN subtitles.
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AlexL reacted to a post in a topic: About the Russian aggression of Ukraine
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AlexL reacted to a post in a topic: Objectivism Online is Twenty Years Old!
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Vlad Vexler, the author of this video, is a doctor of political philosophy. He was born in Soviet Russia. His family left Russia after the fall of the USSR. Vlad is 40 years old. He is a British citizen living in London and continue to closely observe and analyze Russian politics.
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AlexL reacted to a post in a topic: Shameful Display of Anarchy and Violence
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OK, thank you.
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If this is (also) for me, could you please decode it? Who is "belligerent sycophant" etc.? Please.
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Gen. Keith Kellogg words do not support the "longer game" hypothesis. They support "the simplest hypothesis", which stays on the table and thus got even stronger than before.
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AlexL reacted to a post in a topic: About the Russian aggression of Ukraine
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tadmjones reacted to a post in a topic: About the Russian aggression of Ukraine
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Site " 1420", Daniil Orain, micro-interviews, 25 February 2023, in Moscow. Theme: "What do Russians think of Putin? (with blurred faces for more honest answers)"
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So: our common conclusion is now that for both free and interacting particles, the total momentum of a closed system is conserved in the Newtonian, as well as in relativistic mechanics. For the Wigner Theorem and the No-interaction Theorem this means that, whatever they say [you didn't really specify...], they do not, in fact, imply non-conservation. PS: Your justifications/comments to point #1 seem extremely confusing to me. We can discuss this, if you wish.
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I was trying to put some order in our discussion, which is about a subject which is already complicated and doesn’t need a multiplication of issues. I asked two questions. Please answer them. Here are they, with some of their context : The implication seem to be that in an isolated system (isolated from external influences), where the constituents do NOT interact electrically (why only electrically, btw?), the total momentum is not conserved. (You added that this is specific to the 4-momentum, that is to special relativity only, because in the Newtonian mechanics the total 3-momentum is conserved.) 1. Do you agree that THIS would be the implication? 2. Do you insist that this is also factually true, that is that the total momentum of a system of non-interacting relativistic constituents is NOT conserved? I believe there must be a misunderstanding somewhere, because the 4-momentum conservation of an isolated system is a well established observational fact – whatever the interaction between the constituents is, including when it is absent. Depending on your answer, we will see - if there is indeed a contradiction between what we see and the results you’ve mentioned – the Wigner Theorem and the no-interaction theorem, - or that the results you’ve mentioned do not, in fact, imply non-conservation PS: regarding the necessity to also account for the interaction fields - I already addressed this by specifying: "please note that I do not define “total momentum” as the sum of individual momenta." This implies that the total momentum I was talking about also includes the contribution from the fields.
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You din not provide a credible reference/proof that the casualty numbers are true or even that they come from Mossad [*]. Therefore they can be safely ignored (Hitchen's Razor, e.g.). Also, a credible fact-checker shows that the numbers - of human casualties - lack plausibility. Saying this does not mean endorsing other numbers, especially those coming from Ukraine or Russia, the warring parties. The characteristic of a propagandist is that he does not provide proof for its claims and, even if asked to, refuses to do so. And, instead, switches to name calling. --------- [*] Besides, there is not much reason for Mossad to dedicate its own resources to determine independently the number of casualties. Moreover, Mossad is by far not infallible, despite its reputation.
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AlexL reacted to a post in a topic: About the Russian aggression of Ukraine
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Your initial assertion was: The implication seem to be that in an isolated system (isolated from external influences), where the constituents do NOT interact electrically (why only electrically, btw?), the total momentum is not conserved. (You added that this is specific to the 4-momentum, that is to special relativity only, because in the Newtonian mechanics the total 3-momentum is conserved.) 1. Do you agree that THIS would be the implication? 2. Do you insist that this is also factually true, that is that the total momentum of a system of non-interacting relativistic constituents is NOT conserved? I believe there must be a misunderstanding somewhere, because the 4-momentum conservation of an isolated system is a well established observational fact – whatever the interaction between the constituents is, including when it is absent. From this observational fact it follows that any considerations which contradict it (Wigner theorem, non-interaction theorem) are either false or do not, in fact, contradict it (the fact of conservation, that is.) (Just in case: please note that I do not define “total momentum” as the sum of individual momenta.)
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Boydstun reacted to a post in a topic: What Is Quantum Mechanics
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Your insert "[linear]" suggested to me, maybe mistakenly, classical mechanics (vs relativistic); I didn't perceive it as "vs. angular". PS: Standard terminology: conservation of angular momentum is the consequence of the isotropy of the space, of the invariance under rotations, of the Lagrangian, for example.
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Yes, I added "and time" because in the previous paragraph I was mentioning both non-relativistic and relativistic case. You quoted me: but the insertion "[linear was yours]". My two paragraphs: are thus correct and consistent. I believe the misunderstanding is thus solved. The main point, the e.m. field being necessary for the conservation of momentum - I hope @Bill Hobbawill explain his thoughts.
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Boydstun reacted to a post in a topic: What Is Quantum Mechanics
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Hoover Institution, Uncommon Knowledge Host: Peter Robinson Guest: Stephen Kotkin, historian Subject: "A Historian of the Future: Five More Questions for Stephen Kotkin" Questions: What are we doing in Ukraine? 1:35 How will this [Ukraine war] end? 23:02 Taiwan 51:51 Are there still high-profile US politicians as there were before? 1:08:17 Is the 21st century going to be The American Century, as the 20th was? 1:24:54 For @whYNOT: <sarcasm>This Kotkin is another victim of the Western totalitarian media propaganda</sarcasm>
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Intriguing... Just a question of detail: Can you please elaborate - at any level you feel comfortable with? I am surprised because, in classical mechanics at least, the total 3-momentum of a system is conserved (in the absence of external forces/fields), whatever the internal interactions are, that is with or without the electromagnetic fields. And this holds also for the relativistic 4-momentum. In both cases, the conservation of momentum follows from the translation invariance, that is from the homogeneity of space (and time)... Did Wigner imply that without the existence of the e.m. interaction the translation invariance would break ??? That, IOW, the existence of the e.m. interaction can be deduced from the premise of translation invariance?