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As some of you may already know, the SFN server hardware is currently located in the UK. I will quote from what was announced to the staff: “This year the UK government passed a bill called the Online Safety Act. A brief description of the Act is set out here, but the tl;dr of it is that there are now a set of laws in place in the UK that put a duty of care on operators of social media sites in order to make them accountable for the things that are posted on those sites, which could be harmful to children and other users. The focus in the media has mostly been around the larger sites like Facebook, but actually, the act is extremely broad” The upshot of this is that a modest operation like ours can’t be hosted in the UK on servers run by SFN; the requirements are too onerous and no individuals should be asked to take on the liability should someone find that weren’t compliant in some detail. It’s not enough to think we’re taking the right steps, and we don’t have lawyers on retainer to make sure of things. (Small UK bulletin board sites might be shuttering by the end of this week if their owners are aware of what’s going on) Shifting to a hosting option that avoids this is moving forward. This might end up being completely transparent to our members and visitors, but Murphy always seems to pop up and invoke their law, so there might be disruptions. We will keep you apprised as more information becomes available.4 points
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Don’t be a jerk. The issue has been explained to you. The precaution of recalling the product is perfectly sensible as there is a risk, to immunocompromised users of the product, if to no one else.3 points
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I use it in the formal sense as defined in differential geometry, ie as a structure that allows you to meaningfully define the inner product of tangent vectors at points on the manifold, which in turn gives a meaningful notion of lengths, angles, areas and volumes. Yes. You need to be careful here - the Christoffel symbols and the connection are not the same thing. A connection allows you to relate tangent spaces at different points on the manifold to one another, ie it provides a notion of parallel transport. This is quite independent of any metric, which is to say you can meaningfully have a manifold that is endowed with a connection, but not a metric. The Christoffel symbols then give you the connection coefficients, ie they tell you what effects your connection has in a particular coordinate basis. They do this by describing what happens to basis vectors as you transport them between neighbouring points, which is something you can calculate from the metric and its derivatives. Without a metric you can still do parallel transport, but you can’t tell what happens to lengths and angles when you do it. Long story short - you can have a connection without a metric. See above. Having a different metric changes the Christoffel symbols (they are not tensors!), but not the connection. Ok, but in the context of physics (SR/GR) the term “metric” is most often used in the differential geometry sense. Physically speaking, equivalence then means a diffeomorphism, so that both metrics describe the same spacetime and thus physical situation. But here’s the thing - as explained above, you’re still on the same manifold endowed with the Levi-Civita connection. By changing the metric like this, you’re doing one of two things: 1. You’re describing a different spacetime, ie a different physical situation, since the two metrics aren’t related by any valid diffeomorphism; or 2. You’re describing the same physical situation, but the coordinates you are using no longer have the same physical meaning. I think what you are trying to do is (2). But the thing is that now measurements on your mathematical manifold (ie in the model) no longer correspond to measurements in the real world, so anything you calculate from this - eg the length of a world line - must first be mapped back into suitable physical coordinates to compare them to real-world measurements. Such a mathematical map may or may not exist, depending on the specifics of the setup. This will also change the form of physical laws, so all the various equations etc will be different for each choice of transformation you make. In either case, this creates a lot of additional work and confusion, for no discernible benefit. It would look for differences in the outcomes of experiments if you vary direction of relative motion, as mentioned previously. For example, if a uranium atom decays if you move it in one direction, but doesn’t decay if you move it at a 90° angle to that direction (everything else remains the same), then you have anisotropic space. This has nothing to do with conventions.3 points
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Just to elaborate a bit more. When we speak of the invariance (not constancy!) of the speed of light, what this physically means is that the outcome of experiments is always the same in all inertial frames, ie uniform relative motion has no bearing on the outcome of experiments. This has nothing much to do with units or numerical values. Yes, it is always possible to describe the same physical situation in terms of different “geometries”, if you so will. You can eg forego any reference to curvature completely by choosing a different connection on your spacetime - the geometry is now curvature-flat, and instead contains all information about gravity in the form of torsion. But all this is saying is that one can draw different types of maps over the same territory, like having a topographical map vs a road map over the same region. That way you emphasise different information, but the actual experience of physically crossing that terrain is always the same, irrespective of what map you use to navigate. This is not revolutionary or mysterious, and reveals nothing new about the world. It’s “kind of trivial” as the poster in your screenshot correctly said. So I think if you put enough thought into it, it may perhaps be possible to come up with a mathematical description of spacetime in which c is explicitly a function of something. The reason why no one uses such a description is that any measurements of space and time obtained from this description won’t directly correspond to what clocks and rulers physically measure in the real world - you’d have to first map them into real-world measurements, which means additional work and complications without any discernible benefit. Irrespective of what description you use, the outcome of experiments will still be the same in all inertial frames, and this is what we actually observe in the real world.3 points
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Except again, he is business man, but not a scientist. Bezos founded Blue Origin, but no one calls him a scientist because of that. It is fine to say that one admires his entrepreneurship and his business sense (until recently, perhaps). But I don't think it helps your argument by describing him as something he isn't.3 points
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https://www.nature.com/articles/s41586-025-08800-x As the title of the study suggests, researchers found evidence that shingles vaccine might delay or prevent dementia. It is based on prior work which have found that herpesviruses might be implicated in certain forms of dementia. The study also found evidence that beyond the virus there might be some modulation of the immune response that could contribute to dementia protection.2 points
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Faith is the ONLY thing people have for belief in god(s) and is perhaps the single worst reason to accept something as valid.2 points
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From the fact that calling it the F-Trump would’ve pleased the wrong audiences. 🥸2 points
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There is also a broader issue that you do not want to have uncontrolled bacterial growth in your products. If it is not safeguarded against "safe" bacteria, they may also be vulnerable to harmful ones. And generally speaking, it is better to prevent issue rather than letting it run its course until someone is harmed. That is, unless the penalty is cheaper than safeguarding, which then would be a regulatory issue.2 points
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While all newscasting is done by humans and all humans have biases, some sources are particularly good at avoiding spin and focusing instead on providing objective information not on tribal preconception reinforcement and narrative creation (PBS Newshour, as one example), but watching it often feels like eating broccoli so few put forth the effort and prefer the simple “ooh that makes me feel good” stuff. I also advocate for triangulating data across multiple mostly trustworthy sources (such as national defense or global economy focused sources) and forming your own views based on how they overlap and differ with one another, much like you said: On another note… dear leader will now get a new plane from Boeing in the F-47. Trump is an infant with daddy issues.2 points
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Yes I did. I also took the trouble to research my post and provide some factual sources and date checking, which is a lot more than you did. Do you really believe that the US government was not entitled to carry out a surgical strike to kill Osama Bin Laden in the wake of the largest terrorist assault in history - one which killed more Americans than Pearl Harbour did ? - And if not why not ? Where is your argument ? Why did you try to pass off a photo from 2011 as if were relevant to an issue in 2025 ? I don’t like deceit and innuendo. Say what you mean, and mean what you say.2 points
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Why can't I permanently eliminate the rust spots in my tub? Apparently rust will go through a lot to survive. Just saying, it's very easy to anthropomorphize processes that are not at all conscious. Natural selection leads to DNA code that preserves and replicates itself very well. That doesn't mean DNA is conscious or has wants. This is an assertion you (Gees)(messed up quote box, sorry) keep making, one which is not supported by any evidence, and would be rejected by most biologists (myself included) as a metaphysical conjecture. Awareness has, in research so far, correlated with a complex neural structure in multicellular animals. You would hope the member understands how the site works by now. And read the posting rules, on providing citations. Given their tenacity and posting length, I found their plea of fatigue unconvincing.2 points
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Might have closed the gap...but even in that "World Class" group...Trump would be an outliar Best ever!2 points
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Another very important point that I think has not been mentioned here is the role of DEI to identify inequity in the population. One example we discussed in a different context is maternal death rates. As a whole, the USA has one of the highest maternal death rates among high-income countries. Something like 24/100,000 compared to, say around 6.5/100,000 in the UK or 3.2/100,000 in Germany. Now, if you look at the data more closely, you can see that the high death rates are more than double in black compared to white women. Pre-pandemic the rate was about 37.3 for black women (per 100,000), 11.8 for Hispanic and 14.9 for White. During the pandemic there was a general increase, but for black women the rate was 69.3 (1.9x increase), 18.2 for Hispanic (1.5x increase) and 19.1 for White (1.3x increase). Thus, by collecting this more detailed data it is apparent that the health structures in the USA are especially weak for black women and is way better at supporting health for white women. The next step is of course to identify weaknesses and ways to address them. By stopping DEI and related initiatives, the government is blinding itself to this information and money injected into the system will likely disproportionately flow into areas serving white women (even if there is a simple equal distribution) where the health benefits will be the least. In other words DEI is a system that allows us to go beyond simple narratives and helps us to figure out disparities and address them. It does not mean that all initiatives are successful or even helpful, but the idea of being "woke" in this context merely means that we are collecting and looking at data rather than substituting them with ideology.2 points
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OMG, try checking out who really grooms children and abuses them. It's not the drag queens or trans folks, it's white Christian males almost every time you look. Youth pastors, ministers, policemen, white men working hard to abuse positions of authority while they pretend to be "on your side".2 points
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"A popular theory holds that the Mafia began with the Sicilian Vespers and is an abbreviation for "Morte ai Francesi, Italia Anela!"[47] ("Italy desires the death of the French")." https://en.wikipedia.org/wiki/War_of_the_Sicilian_Vespers On Wikipedia it is mistranslated, as it should be “Death to the French, Italian breathe hard.” IOW, such a combat saying, to warm up the soldiers to fight. The origin of all ancient words is very difficult to determine. Unless you create an acronym for yourself. ps. Soldiers returning from the war, do not have a job, so they begin to commit crimes, and as they were already in one organized crime organization ("the army"), so the hierarchy and organization they have ready.. ps2. Did you try Wikipedia? https://en.wikipedia.org/wiki/Mafia#Etymology "maʿfī (معفي) = exempted. In Islamic law, jizya is the yearly tax imposed on non-Muslims residing in Muslim lands, and people who pay it are "exempted" from prosecution." "maʿāfir (معافر) = the name of an Arab tribe that ruled Palermo.[14][10] The local peasants imitated these Arabs and as a result the tribe's name entered the popular lexicon. The word Mafia was then used to refer to the defenders of Palermo during the Sicilian Vespers against rule of the Capetian House of Anjou on 30 March 1282.[15]"2 points
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It’s hard to tell if this is a serious question. Partly because of your “jokes” and partly because you don’t seem to have done a lick of research on the question. Incessant whining, based on ignorance, is hard to take seriously. The Apollo missions cost more than $300 billion in today’s dollars. (2023) https://taxfoundation.org/blog/apollo-moon-space-race-industrial-policy-cost/ (original cost was ~$25 billion) This shows that each mission cost less than $500 million, so even if you shave off the last 6 missions, that’s less than 1/8 of the overall cost (3 billion out of 25) https://www.statista.com/statistics/1028322/total-cost-apollo-missions/ So the new program is a lot cheaper, because certain things don’t have to be re-discovered, even as the hardware is remade with modern technology. But it’s not simple and it’s not easy.2 points
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No, you were poking fun at the cost of a trillion dollars, which you either made up or didn't bother to check after you heard it. Let's be clear about your intentions. I don't think you understand any of this. Your arguments are childlike, as if your experiences haven't taught you how to reason correctly. Like many conservatives, you have a caricature in your mind about most of the things you don't understand. It's what's held up progress for as long as humans have been around. Progressive thinking got us to the moon, while the conservatives argued it was a big waste, just like every other major innovation humans have accomplished. When it comes to progress, there's never a conservative contributing to the future. If you truly wanted to eliminate the need for DEI, your methodology is unacceptable. Your prejudices are too prevalent.2 points
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Trump would like to carve up the world between three strongmen leaders: himself, Xi and Putin. So he wants to annex Canada and Greenland, take back the Panama Canal for strategic access to both coasts and oceans by sea, get out of entanglements in Europe, which he sees an economic rival and nuisance with all its pathetic concerns over outmoded ideas like democracy and social welfare - and let Xi have Taiwan, once he has got the chips being made in Arizona. If Putin fights with the EU, so much the better. It's Orwell's vision of Oceania, Eurasia and Eastasia.2 points
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I think you’re right. With their last post it’s clearer to me what their misconception is. The wire’s length is only contracted in the electron’s frame, not the lab frame, so there’s no reason to expect the result they claim.2 points
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Here's the paper: https://www.nature.com/articles/s41467-024-55662-4 Sadly it is written in the usual, almost unreadable, style of so many papers these days, but the graph of the decay curve they obtained, from their measurement of samples, was interesting: Fig. 2: 10Be concentration vs. age measured in crust VA13/2-237KD. The bump is the anomaly. This graph suggests they can use ¹⁰Be for dating up to 14Myr or so (except obviously where the flat bit is, from ~8-10Myr).2 points
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\[ \gamma=\frac{1}{\sqrt{1-v²/c²}} \] \[ \gamma\times0=0 \] Last comment by @Markus Hanke & @swansont spot on, I think. You cannot take electron density in proper frame for electrons while proton density in "rest" frame.1 point
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The speed of electrons in copper noted in my previous post imply you would have to apply 1011 volts to boost their flow speed to 0.1c1 point
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That's nice for them. But not really important. https://en.wikipedia.org/wiki/List_of_countries_by_thorium_resources Plenty of countries have large stocks of it. (Even the UK has a bit)1 point
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Have you misunderstood what the post you quoted was saying? I felt it was criticizing Trump's greedy eyes and likening his approach to that of Russia.1 point
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Yes, the good thing (if there is anything "good" about this disaster) is this shows German people are alive to the seriousness of the sudden switch in alliances. We will all (and I mean the UK and Norway plus the EU) need to put our hand in our pocket to fund a rapid rearmament of Europe. Taxes must rise and we need a lot more of those excellent German panzers. Not only to help Ukraine but to defend the eastern boundary of the EU, especially Poland and the Baltics. The USA is no longer an ally and could easily become the enemy, at least in terms of intelligence sharing and cyber warfare. We have to kick the US out of the Five Eyes system. Anything we tell them may go straight to Moscow.1 point
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I can see your point, and you are of course right. The kind of density I had in mind though was a different one - I took the balls to be extended objects, and mentally considered the ratio between ball radius and tube length, ie which proportion of the tube volume is occupied by each ball. Since both are length-contracted by the same factor, this ratio does not change. In my defense, I tend to have a tendency to seek out invariant quantities when looking at relativistic scenarios. But I don’t think that’s what the OP has in mind, unless I’m still misunderstanding him. He is comparing the same circuit from the same frame, only with current off and on, and argues that because the electrons are in motion, the distance between them decreases, and thus there’s a larger net negative charge in that section of the circuit because there are more electrons in that same length of wire. He never mentions the rest frame of the electrons, nor the EM fields. What I’m saying here is that the distance between the electrons doesn’t change just because you turn on the current, because the observer is still stationary with respect to the circuit; there’s no length contraction of distances in the wire in the observer’s frame. In other words, the total amount of charge is the same, it’s just that this charge is flowing rather than standing still. I have, but I don’t think that’s what the OP had in mind, see my comments above.1 point
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Hopefully this is your Eureka moment. There have been several times in history where there were suddenly a lot of discoveries that need names. You live in one it is called America. So not all discoveries were in Chemistry or even scientific.1 point
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Yes, mist, steam or condensation. You could collect a bottle of it then cool and let the clear liquid settle then compare it with some water from the faucet. The main thing is that you meet the stuff often enough to have named it. That is exactly what Dalton, Lavoisier etc did. This is also exactly what Scheele did when he discovered Chlorine. He grabbed a bottle of it and noted that it was not clear like air but had a greeny yellow tinge See the picture of a bottle on Wiki https://en.wikipedia.org/wiki/Chlorine1 point
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When the temperature drops and you see 'stuff' coming up from beneath the sidewalks or you just breath out and see 'stuff' what do you call it ?1 point
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We forget things that are a few years (maybe months/weeks?) ago. I am also worried that there there is just so much going on that just the latest biggest thing erases everything else (considering e.g., the historic gains of the AfD). (Weidel is the current leader of the AfD, Estwaehler are folks who voted for the first time). There are politicians in Germany who called the holocaust a "Fliegenschiss" (literally, fly shit, meaning something insignificant), in German history. The world is shifting, powered by a never ending stream of idiocy. And I would be very angry, too, if I wasn't so tired.1 point
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I don't any one disagrees that merit (experience, education, skill, ability, etc) should be determinant above race, gender, religion, etc. The exaggeration in the conversation is the suggestion that they is always an individual superior choice and that due to DEI that choice isn't selected. Provided all applicants meet the qualifications everything else is subjective. I think athletics drafts are a good analogy. Teams attempt to pick the absolutely best athlete they can find using stats, in-person workouts, and interviews. Yet some of the greater athletes in history were past over in favor of inferior ones. Pick the singular best person for something is actually very difficult. Yes, that is already the standard. You are saying it "should be" and it is. Individuals that meet the standards outlined for a position or role have the merit required. What gets wrestled with is the competition between greater leaves of merit. Which are seldom even applicable. Most of the time, provided everyone meets the minimum standards, enthusiasm is probably the best attribute. In society assumptions get made and we often look for the more perfect candidates. Amongst student athletes competing to be the Center on a basketball team the tallest athlete probably gets it. The assumption being height provides an advantage. Simply being the tallest is no guarantee of athletic ability though. It is just coaches playing the odds and being willing to invest more in one athlete over another. Height is merit if we are defining merit as earned skills and abilities. There are minimum standards. There aren't maximum standards. It's all subjective above the minimum standards. Some standards are arbitrary some are crucial. That is why standards are routinely updated and revised.1 point
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Kefir seems to have the most bacteria types in it. I've got some dried inoculant to try sometime.1 point
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Unthankful fish obviously attacked the snake, and noticeably isn't even in a suit and tie...1 point
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That is why I have been holding back about the last stage and how we got to our present view of atoms and molecules. If you look at pages 38 and 39 of the World Treasury book I recommended and I believe you bought you will find the first two pages of an article about electrons by early 20th century physicist George Gamow. Never mind the electrons we will come to them eventually so don't bother to read the whole article for now. I have mentioned divisibility and indivisibility a couple of times in this thread. The ancient Greeks spent a lot of time arguing about this subject. The arguments were not just to do with substances and matter but space and time as well. The famous paradoxes of Zeno are some examples. The Aristotle camp believed that you could go on cutting matter into smaller and smaller pieces for ever. That is an infinite count of cuts. As George describes the alternate camp led by Democritus believed that you would reach a stage where you could cut or divide no more. This he believed that there waas a smallest particle he called atomos. We do not now how a clear reason why he thought this. But we do know that the Greeks never resoved their argument. Roll on just over two thousand years and Dalton and other scientists discovered evidence to support this contention. They found that regardless of how many experiments they did the proportions in either their analysis or their synthesis of substances was always the same regardless also of the total quantities employed. It was clled The Law of Constant Proportions. This law has remarkable implications because it means that if you try to synthesise a substance from its elements in any old proportions there will always be and amount of substance and an amount of one element or another left over unused. Think very hard about this because it can only be true if Democritus was right and there is a smallest piece of any substance or element. For example you cannot tack on an extra third or one sixteenth of a piece of oxygen to water. Come back and talk about this idea until you are happy with it and then we can move on again.1 point
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Perhaps it would help if you read the Wikipedia article on the history of atomic theory: https://en.wikipedia.org/wiki/History_of_atomic_theory Knowing the history of atomic theory provides an understanding of how the knowledge of atoms developed over time.1 point
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Don’t be so touchy. On the internet we don’t know who we are dealing with and I’ve got burnt in the past by timewasters, as have many others here.It takes a while to develop a rapport and trust with someone new. That’s what I mean by bona fides. It was a peculiar question for you ask so I became a bit suspicious, that’s all. But up to you if you prefer to continue with someone else, of course.1 point