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Showing content with the highest reputation on 04/26/24 in all areas

  1. I'd add: learning latex would be a good start. In the photo of math, it's not all oriented the same way as the forum, and being a photo is impossible to properly quote, or dissect for discussion. Nobody is being paid to review your posts, if you want feedback you need to make the interest high and the effort low. I will say your handwriting is very good.
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  2. I admit, we discriminate against people who don’t follow the rules.
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  3. It is unfortunate that most observation stations have been set up like this one at Hooper, Colorado.... https://en.wikipedia.org/wiki/UFO_Watchtower So instead of attracting scientists who can set up proper recording arrays, it attracts the true believers (or tourists looking for something offbeat). Or nuts, e.g. Me too. I figured "providence" was provenance.
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  4. You might want to check the Dictionary of Obscure Sorrows
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  5. You never know! All kinds of people come up with all kinds of wonderfully unique descriptive words - either because the context is or at some time was significant in their culture, or because one of their poets or jesters coined one that everybody considered worth repeating. There is a Hungarian two-word phrase for spilling food down the front of one's clothes. There is no way anyone could ever have thought that was important to note, but somebody said it and it's funny, so people keep using it. I've heard there is a word in Japanese for the urge old people get to pinch a baby's cheek. It's not that significant, but somebody noticed it and named it. People talk about feelings in many ways, but we share the feelings pretty much all around the world.
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  6. Trump thought he had Pecker in his hand... (he's a one ball man, he's off to the rodeo)
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  7. There have been numerous surveys among natural scientists back in the 90s and 2000s, when teaching evolution was heavily attacked by the conservative establishment in the US. The overall trend was overall lower religiosity when compared to the average population, but also interesting trends depending on discipline. IIRC the questions were more general, like "do you consider yourself religious" rather than asking things specific to a system (e.g. god or gods). I believe biologists had the lowest number of religious folks whereas, mathematicians and medical folks had higher. I am sure they must still be available somewhere.
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  8. ! Moderator Note You posted this in classical physics, about optics. Optics is what needs to be discussed. Not karma or creepiness or arachnophobia (which you had a thread on, and it was closed) or any unsubstantiated musing on any topic.
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  9. I came upon a passage the other day which reminded me of an issue now mostly forgotten, but one which was very important to Allied military planners back in 1945 as WW2 entered its endgame - and that was the fate of allied POWs and incarcerated civilians who were in the hands of the Japanese throughout the Far East. http://www.mansell.com/pow_resources/liberation_photos.html Over 190,000 British and Commonwealth troops were taken prisoner by the Japanese during WW2 - many of them when Malaya, Singapore, and Burma were overrun, and some 32,000 Allied POWs were subsequently repatriated directly from Japan itself after the end of the war. The majority of these prisoners were kept in appalling conditions on starvation diets and and many were worked to death in slave labour camps, like those working on the Thai-Burma Railway at Kanu Camp Thailand, where 60,000 British, Commonwealth and Dutch prisoners worked on the railway, and 16,000 of them perished doing so. https://www.iwm.org.uk/history/what-life-was-like-for-pows-in-the-far-east-during-the-second-world-war There is some vivid testimony from two such prisoners who later became very well-known novelists. One was the Australian born James Clavell who wrote the screenplay for The Great Escape (1963) and later wrote the first of his ‘Asian trilogy’ novels Shogun (1975) partially around his war-time experiences at Changi prison in Singapore. The other was the British writer J.G. Ballard whose family was interned in the Lunghua internment camp near Shanghai in China, and based his autobiographical novel Empire of The Sun (1984) on childhood memories of life there. J.G. Ballard incidentally claims that he and other occupants of the Lunghua camp actually saw the flash of the second atomic bomb when it detonated over Nagasaki 500 miles away across the East China Sea on the morning of August 9 1945. Both of these writers make the point that the atomic bombs dropped on Japan in 1945 probably saved their own lives and those of countless other POWs and internees, because many of them simply could not have survived the effects of chronic malnutrition they were experiencing at the hands of the Japanese for much longer. They might well have been dead if the war had ended 6 months later. James Clavell who was living on 110 grams of rice per day, one egg per week and occasional vegetables in Changi prison camp was unable to talk about his wartime experience for 15 years, but later disclosed that for quite some time after, he kept a can of sardines in his pocket at all times, and had to fight the urge to forage for food in rubbish bins.
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  10. ok First off you have vacuum energy and vacuum energy density confused. The first case though not a useful form for energy density. The VeV is the vacuum expectation value VeV this isn't the density. This is a term describing the effective action https://en.wikipedia.org/wiki/Effective_action for Higgs the effective action is defined by the equation \[v-\frac{1}{\sqrt{\sqrt{2}G^0_W}}=\frac{2M_W}{g}\] here \(M_W\) is the mass of the W boson and \( G^0_W\) is the reduced Fermi constant. These are used primarily when dealing with Feymann path integrals in scatterings or other particle to particle interactions involving Higgs in particular dealing with the CKMS mass mixing matrix. So its not your energy density more specifically they describe CKMS mixing angles or Weinberg mixing angles. for the above without going into too much detail the mixing angles are \[M_W=\frac{1}{2}gv\] \[M_Z=\frac{1}{COS\Theta_W}\frac{1}{2}gv=\frac{1}{Cos\theta_W}M_W\] more details can be found here. Page three I'm starting to compile the previous pages now if you want the vacuum energy density the FLRW has a useful equation. \[\rho_{crit} = \frac{3c^2H^2}{8\pi G}\] if you take the value of the Hubble constant today and plug it into that formula you will get approximately \(5.5\times 10^{-10} joules/m^3\) if you convert that over you will find your fairly close to 3.4 GeV/m^3 which matches depending on the dataset used for the Hubble constant. The confusion you had was simply not realizing the VeV isn't the energy density. hope that helps. I won't get into too many details of the quantum harmonic oscillator via zero point energy but if you take the zero point energy formula and integrate over momentum space d^3x you will end up with infinite energy. So you must renormalize by applying constraints on momentum space. However even following the renormalization procedure you still end up 120 orders of magnitude too high. There has been resolutions presented to this problem however nothing conclusive enough. Quantum field theory demystified by David Mcmahon has a decent coverage of the vacuum catastrophe edit forgot to add calculating the energy density for the cosmological constant uses the same procedure as per the critical density formula.
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  11. The equivalence of frequency let's term it Mj or Kihara equivalence....mmm... selfish... 😋. Pliz give the reason for a red tick,think about it is complicated without reasoning.
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