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  1. 3 points
    It is confusing. You can't find a clear example of someone being called a liar, but still think it's a problem?
  2. 3 points
    While female and male brains have differences, it would be difficult to pick apart what is truly biological variance between populations and what is cultural conditioning. I vaguely recall a study that found female hippocampi were on average smaller than in males, which was said to explain why men were better navigators. But we also know parts of the brain less used will atrophy. So is it a case of their hippocampi being intrinsically smaller, or a result of gender roles directing its use (or lack of)? When women have risen to prominent historical roles they have pretty much done as men have done - Wu Zetian, Boudicca, Hypatia (but maybe that's because they emerged in patriarchies). There is also evidence of early societies that while not matriarchal, were more balanced. The Spartans are a probably the best documented example, and weren't significantly different from surrounding societies. I've also heard it said men more readily pursue risky pursuits, perhaps leading to voyages such as Colombus'. Assuming this is a neurobiological difference, it wouldn't necessarily preclude risky behaviour from men. Remember Colombus was sponsored by both Queen Isabella and King Ferdinand, with the former willing to sell some jewels to fund it (thoough she didn't need to). War would still be conducted by men on the field; aside from differences in physiology making men on average more suited to those demands, sending women to fight would be a flawed strategy. The Romans lost ~300,000 men to Hannibal in the Punic wars from a total population of ~3.5 million - thats a huge proportion. If they had all been women of child-bearing potential Rome would almost certainly have fallen. Overall i don't think there'd be gross changes to the patterns of war, economic cycles, spiritual practices, technological development etc - just a lot of changed details which are impossible to guess at. They say men are from Mars and women from Venus, but we all know they're both from Earth.
  3. 3 points
    That is not what "squaring the circle" means. Given a circle of area 1, yes, there also does exist a square also of area 1. That is not a problem. The problem is that from a line segment of length equal to the radius (or equivalently the diameter) of such a circle, it is not possible only using ruler and compass to construct a line segment to make a side of a square of the same area as the circle. The claim in your old book does not make immediate sense. It is true that if you are given a line segment of unit length, then you can quite obviously construct a square of unit area. But having been additionally given a circle of unit area would not be helpful in any way to do it.
  4. 2 points
    https://phys.org/news/2020-01-particle-chip.html This image, magnified 25,000 times, shows a section of a prototype accelerator-on-a-chip. The segment shown here are one-tenth the width of a human hair. The oddly shaped gray structures are nanometer-sized features carved in to silicon that focus bursts of infrared laser light, shown in yellow and purple, on a flow of electrons through the center channel. As the electrons travel from left to right, the light focused in the channel is carefully synchronized with passing particles to move them forward at greater and greater velocities. By packing 1,000 of these acceleration channels onto an inch-sized chip, Stanford researchers hope to create an electron beam that moves at 94 percent of the speed of light, and to use this energized particle flow for research and medical applications. Credit: Neil Sapra
  5. 2 points
    TBH, even if not applicable it is one of the things that POC often face when getting criticized for something that their peers are not. Overtly, it is never about race but something else. Weirdly, however, there is much larger pile of the "definitely-not-related-to-race-issues" on someones desk. Of course no one ever acknowledges it and the imbalance must clearly always be about something else.
  6. 1 point
    Holy cow . I have read through 2-3 threads in this area, and the amount of vitriol that gets aimed at people is amazing . “STFU, you stupid, ignorant denier” seems to be the standard attitude . Not a “denier” , BTW. But I am amazed at what I have seen reading on a science site . I have read comments from scientists about how they were hatefully attacked , stalked , fired , etc for expressing concerns about issues in the climate science processes , and then I come here and see it on a smaller scale in a place I expected to see rational , scholarly and respectful debate . Seems to be a pattern here . Not good .
  7. 1 point
    Actually, no. Probably not. Much more likely is confirmation bias.
  8. 1 point
    Or men have larger hippocampi because they were encouraged to explore the world as boys, as girls were encouraged to domestic play (recently came across this with my niece who wanted a remote control car as a present but the mother over-ruled her to get a cooking toy). If we're imagining a society starting from scratch we'd need to know the direction of causality, at the moment we have only correlation (as far as i know - haven't delved into the literature). Again, how much of this is biological and how much cultural conditioning? My impression is that any biological differences are exaggerated by cultural norms. To imagine a truly matriarchal nascent society we need to strip away this cultural element, leaving us with a biological case from which to proceed (although it probably isn't as easy to separate culture and biology as i suggest given one emerges from the other). Maybe there are animal studies that could give us some clues?
  9. 1 point
    He's limiting the options of possible interpretations and excluding reasons like naivete or ignorance. His glass is half empty.
  10. 1 point
    I would hope that after decades of talk on the need to deal with climate change there would be some substantive plans somewhere on how to go about it . Otherwise it’s like going to your doctor and being told your blood pressure is way too high and that this will have bad negative effects on your future health . “ OK then doc, why do I do about it ?” ”Well, you just need to get your BP lower . Down in the 120-130 range instead of 160” ”Yeah , but how ? You going to prescribe some pills ?” ”No” “So what then? Eat better, exercise , quit alcohol? What exactly do I do to lower it ?” ” I don’t know, but you need to do something to fix it or you will likely have a stroke or heart attack within 10 years “ Hopefully this is not the case , and there are no solid ideas on how to do something we are told in repeatedly that is imperative we do NOW . How do we do NOW what we need to do to alleviate the climate crisis , and what impact will it have on our lives , our lifestyle, and our economy ?
  11. 1 point
    It did not address the OP, so no, it's not. It doesn't address the discussion in the article, nor any effects of AGW. This is why I split this into a new thread for discussion. (original thread https://www.scienceforums.net/topic/120579-climate-science-was-wrong/) I agree with iNow - without examples, it's hard to take such complaints seriously. (The proper procedure is to use the report post function, which identifies the post to the staff) We've run across a fairly significant population who don't actually know what an ad hominem is, and there are also others who can't distinguish between being personally attacked and having their argument attacked. These groups overlap to some degree. For example, using a description of "ignorant" (your example) is not inherently an insult. Ignorance means not knowing something, and everyone is ignorant on a great many topics. It can be used as an insult, as can other words, and it could be applied to a person or an argument, but without context there's just no way to tell. (I find two uses in that thread. One applied to a person, with regard to their article, the other to an argument. Neither was used as an insult) The one time in that thread that someone said STFU it was about someone bringing up an irrelevant article in TIME, which has nothing to do with the topic. It's like telling someone to stop interrupting you while you have a conversation. You might consider that to be an affront, but it's in response to rude behavior and not uncalled for (especially if lesser efforts have failed) Again, we prefer it if staff were notified and so we can take care of it, but to a certain extent, community peer pressure is a viable tool to keep discussion on target. Such as asking of you have anything relevant to say on the topic.
  12. 1 point
    I appreciate your help and patience. 😊 I expected fields to interact, I do not have the ability to explain the balanced forces of I1, I2 & I3 on B4, B5 & B6. I only suspect they do due to some fancy right hand rule gestures. I was going with the fact that steel beams are used as passive shielding in MRI machines. http://mriquestions.com/how-to-reduce-fringe.html
  13. 1 point
    You want addresses for Rangerx and Raider5678 so you can go run them down ? I'm getting tired of the car/driving analogies myself. ( just joking, I don't have addresses...or do I ? )
  14. 1 point
    I like ths... I would think that, since we are increasingly dependent on power, more nuclear ( and fusion research ) combined with solar panel 'farms to provide electric power for all applications ( improved battery tech ) would be a strong positive. Most of the programs pushed by Governments, such as cap and trade, or carbon tax, do little or nothing to reduce GHG emissions, as they just impose a 'cost' to continue doing business as always. Only those that can't afford it are forced to change their ways, so I see these initiatives as a strong negative.
  15. 1 point
    You have never clarified the original question. You have allowed us to interpret the OP as we see it, and once we offer a solution to OUR interpretation, you tell us we are wrong ? How about reposting the original question, as YOU interpret it ( but in a clear manner, not like previously ), and then we can discuss it properly.
  16. 1 point
    Basically, whoever is in the driver's seat of this hypothetical car looks bad. But they also can't stop the car at any given point, they have to drive it to the end once they start. So the House started driving this car, and then worked as hard as they could to quickly send the car to the Senate to drive. Then, they try to make the Senate look bad for driving as fast as they can. Likewise though, the Senate decried the House driving as fast as they could. But now that the Senate has the hypothetical car, they want to drive as fast as they can too. The only difference between the Senate driving and the House driving is the party who controls it.
  17. 1 point
    I am glad your surgery went well. I had a family member have major brain surgery and I know how painful it is. Best wishes on a speedy recovery.
  18. 1 point
    The mass has been removed☺️ Occasionally it feels as if my head has been removed the pain suggest otherwise not to mention that using my cell phone finding my head is not that difficult somewhat ugly but not difficult to do. the fact that I am using my cell phone and am not just sitting here staring at it wondering what to do next in my opinion suggests good days to come. they were gonna give me another 3 months before the procedure but had to move it up. Doing well.
  19. 1 point
    Under certain circumstances you can use either one to describe the same thing, but that is not always the case. As a counterexample, consider the (2D) surface of a (3D) cylinder - it is extrinsically curved, but intrinsically flat. So clearly, in this case these two descriptions are not equivalent. In the case of GR, spacetime is not thought to be embedded into any higher dimensional space, so it has only intrinsic curvature. For arguments sake, it is possible to construct a mathematical model that embeds spacetime into something higher-dimensional, and then use extrinsic curvature to capture all the same information. The problem with this is that the embedding would have to have a lot of dimensions; I can’t actually remember the exact number, but I think it was 48. So I fail to really see the advantages in this, as it makes most of the maths very much more complicated than it already is in standard GR. In general terms, any Riemann manifold can be embedded into a higher-dimensional Euclidean space in such a way that paths lengths are preserved. This is called the Nash embedding theorem.
  20. 1 point
    Gravitational waves are affected by the background curvature of spacetime, and you can get many of the same effects that light would be subjected to, such as deflection, frequency shift etc. However, the actual dynamics of gravitational waves are potentially much more complicated than those of light, because gravity is non-linear, unlike electromagnetism; this means that such waves also interact with each other and with themselves. Can you construct an arrangement that acts like a lens for gravitational waves? Yes, you certainly could, but depending on what exactly it is you are trying to achieve, this may be a very complex problem (both mathematically and practically). This is a very complex topic, and truthfully speaking I have not done (or even seen) the exact maths of how this comes about. The general idea is that you start with a wave pulse (i.e. a more or less sharply defined packet of wave fronts) and send this through a region of spacetime that has substantial background curvature due to the presence of some gravitational source, e.g. a black hole. What happens then is that the wave pulse, as it travels through this region, backscatters off the background curvature, which leads to its shape and polarisation to change in some very specific manner. The deformation is such that a “tail” is produced behind the travelling pulse, and that wave tail propagates at less than the speed of light. My understanding (someone more expert at this particular detail please correct me if I am wrong) is that the wave tail travels at below c due to its own gravitational self-interaction - which is a non-linear process.
  21. 1 point
    You auto have known better...
  22. 1 point
    Sure I just wanted to make sure that "agreed" has very different meanings in the two procedures plus the fact that the talking point as a whole (i.e. everything is following the Clinton precedent) is inaccurate, as I think it is quite important context.
  23. 1 point
    Is it OK to assume that ABD is an equilateral triangle?
  24. 1 point
    No, it just means that they weren’t emitted simultaneously - which is what one would expect, since these two forms of radiation are the result of different physical processes. This is inconsistent with the basic principles of GR, as well as with the specific mathematics of gravitational waves. The opposite is in fact the case - since the dynamics of gravitational waves are non-linear (unlike e.g. EM waves), they interact both with other gravitational waves as well as with themselves. In this manner you get a number of effects that are exclusive to gravitational waves, and some of these actually propagate slower than the speed of light (specifically so-called “wave tails”). However, a free wave in otherwise empty space must propagate at exactly c.
  25. 1 point
    Please provide straight answers. Have you abandoned the first version of the lifter and wish to discuss only the new one? I am still looking at first version: You state that there is an acceleration. Acceleration relative to what?
  26. 1 point
    https://www.universetoday.com/144622/a-mysterious-burst-of-gravitational-waves-came-from-a-region-near-betelgeuse-but-theres-probably-no-connection/ "A Mysterious Burst of Gravitational Waves Came From a Region Near Betelgeuse. But There’s Probably No Connection"
  27. 1 point
    Are the magnetic fields generated in the lift or by another device, not onboard the lift? I assume that Ampère's force law can be neglected, correct? The currents do not generate a strong enough magnetic field to have an effect on the outcome.
  28. 1 point
    So I am taking my first proofs class this semester along with an application of it in mathematical statistics and I got to say. This is pretty awesome. Why have I never seen this stuff before in my lower level mathematics courses. Like it provides general reasoning and evidence for each mathematical equation. I am currently reading over "Journey into mathematics-an introduction to proofs" by Joseph J. Rotman and it answer ssooooo many questions. Like a proof for that cosine equation that was just given to me. I thought it involved like some super human levels of mathematics. It turns out it just uses the pythagean theorem and some geometry identification and relationship forming. Also I am reading "The Elements" by Euclid for class as well, picked it up because it looked kind of cool when I was younger and it turns out I needed it later on, nice coincidence. Turns out it is now my favorite book. Like a book that you do not want to pick up because you know you will not be able to put it down. Like my biggest issue in my math classes was that I did not understand how the conclusion was reached. Like omg, this is the most I have learned in a long time. (source: Family guy) (reason for use: for dramatic comedic appeal ) Is this what math is? finding patterns and relationships in order to develop unique structures in order to better understand the interworks of different behaviors being observed?
  29. 1 point
    You say you understand and then write nonsense like that second sentence, which demonstrates very clearly that you do not understand. Until you can get past this attitude of believing you understand things when you clearly don't, you will not be able to learn and get to understand the things you currently don't understand. There is no such thing as a "tensor force". There is no force causing the expansion of the universe. (In the same way that gravity is not a force.) No. No. No. This is completely and utterly wrong. Please stop spouting nonsense and take some time to LEARN. https://xkcd.com/895/ You don't have any math. You have meaningless collections of symbols.
  30. 1 point
    Formally, no. Informally, spot the fuck on. And of course, with the new structures, you get new patterns and relationships, which need new structures, which ...
  31. 1 point
    What is the source of the magnetic field?
  32. 1 point
    Ok! Just so I follow: due to the force from the magnetic fields the rig will accelerate. How is momentum conserved?
  33. 1 point
    The second link in OP (https://emilkirkegaard.dk/en/?p=7237) states that the 10% claim is "bullshit". It does not support the 10% claim and gives several reasons why the number may be incorrect. Talk page of wikipedia "List of nonreligious Nobel laureates" states "The main source of this article is not reliable": https://en.wikipedia.org/wiki/Talk:List_of_nonreligious_Nobel_laureates#The_main_source_of_this_article_is_not_reliable Good points, I'll add a local example. Wikipedia lists 32 swedish laureates. During the years of Nobel Prizes Sweden have made several changes* to how church and state are related. Those reforms could impact what individuals would have answered at that time compared to more present times. It would require a lot of rigor to be able to produce reliable definitions and a usable list. This is just an example, for one single country, intended to highlight the difficulty with this kind of material. *) https://www.svenskakyrkan.se/church-and-state until year 2000 state and church was united Swedish only found: http://www.notisum.se/rnp/SLS/lag/19510680.htm Until 1952 you had to belong to a religious community, you could exit stat church only if you registered at another religious community.
  34. 1 point
    The word "lifter" seems to suggest that some force will accelerate something so that it lifts. It may help with an overview of what the magnetic lifter is before going into the details of the calculations. Edit: Pictures above are cropped. Instead of having to go to an external site each time I'll insert the picture here:
  35. 1 point
    ! Moderator Note It doesn’t matter what you believe. It’s what you can show, in a scientific context. You haven’t backed up your assertion. So we’re done here.
  36. 1 point
    I am not an expert, so if I say something incorrect, wtf may want to correct it. But i am pretty sure that it only works in one possible way. Namely among the infinitesimals you have to pick a standard one, say call it \(\varepsilon,\) and likewise among the infinite hyperreals you pick an \(\omega,\) and then you arrange that multiplication works so that \(\varepsilon \omega = 1,\) that is to say, they are reciprocals. And in general, if \(a\) is real and nonzero, then \(a\varepsilon\) and \(\omega /a \) would be other possible, and just as good, choices. And you do always get a real number by multiplying an infinitesimal \(a\varepsilon\) by an infinite \(b\omega\) when \(a\) and \(b\) are real. What I think is perhaps a little interesting is that once you have made your choices of \(\varepsilon\) and \(\omega,\) then because you can multiply all hyperreals, there is an even much smaller infinitesimal (it is still called that, right?) \(\varepsilon^2\) and en even larger infinite \(\omega^2\) which you could have picked in place of \(\varepsilon\) and \(\omega,\) without anything working any different. Which indicates that there are even more brutal ways of making smaller infinitesimals than just by dividing by \(2\) or any other large real. The exact converse situation would occur if we were to introduce new hyperreals \(\sqrt{\varepsilon}\) and \(\sqrt{\omega}\) which are hugely larger, respectively smaller, than \(\varepsilon\), and \(\omega\), themselves. It would mean creating an extension of our original field, vaguely similar to how we create \(\mathbb{C}\) as an extension of \(\mathbb{R}\) by adding \(\sqrt{-1}.\) Except in the case of hyperreals, it looks to me like the new extension field is pretty much the same as the one we had already.
  37. 1 point
    That's not how it works. Consider a carbon atom. It is arranged in a specific crystal pattern, and the electrons are in specific orbitals to account for the molecular structure of graphite. And its colour is black. Take those same atoms and associated electrons, and rearrange them so that the crystal structure is different. The electrons for the new molecule bond using different orbitals, but the exact same electrons. And the colour of diamonds is clear. That's the beauty of good science ( as opposed to WAGuesses ), it fits observational evidence.
  38. 1 point
    I think this is the phenomenon. There's a simulation on the page - Click link under quote:
  39. 1 point
    That is a perfectly valid Newtonian equation. Now substitute values in for the variables. For light, m=mo=0 IOW it has zero rest mass because it can never be at rest. So your perfectly valid equation, when mis-applied in the case of light or heat, gives you the non-sensical solution 0=0. Now you're doing Physics . ( being very sarcastic )
  40. 1 point
    ! Moderator Note OK. We are done here. Your "equations" are meaningless collections of symbols with no regard to dimensional analysis. How can "G=F=<E" even mean anything. Do not bring this up again. But, as Ghideon says, you seem to have a lot to learn so please feel free to use this forum as a resource by asking questions.
  41. 1 point
    Violation of Bell’s inequalities does not imply such as thing as “action at a distance” - which is in itself a meaningless concept. Quantum entanglement is simply a statistical correlation between measurement outcomes; there is no causative “action” involved. I’m afraid this is completely meaningless.
  42. 1 point
    We've also seen shadows cast by hydrogen that ends up gravitationally attracted to it. Like seeing the shadow of raindrops on a spider's web.
  43. 1 point
    If I didn't know I would say she was of hispanic heritage.
  44. 1 point
    I think it is because you are given sources, but then do not watch them, while still talking about 'alleged' temperature changes, as if that's not kind of shown at this point? Questions are fine, but it may be good to first fully consider the answers given.
  45. 1 point
    IIRC electrolysis is ~1.25 eV, so it would be 7.5 x 10^26 eV for a kg. That’s 120 MJ, or 33.3 kWh
  46. 1 point
    Evolutionarily, it's a bad idea because the more variation there is the more chance there is of overcoming any future unknown adversity. Arbitrarily selecting for certain traits may reduce reproductive fitness in a population
  47. 1 point
    Hi DrP, nice to see you here! The very nature and usefulness of a forum are the contributions that don't go in the expected direction, so "isn't what you were looking for" is absolutely fine. A somewhat similar attempt was at the octo-basse, an oversized bowed string instrument made by Vuillaume. As the musician couldn't reach the top of the strings, he played the notes' height on a keyboard, and a mechanical transmission pressed the strings at the corresponding length. No electricity needed. And believe it or not, the Montreal symphonic orchestra has recently bought such an instrument. https://www.youtube.com/results?search_query=octo-basse
  48. -1 points
    Isn't the force noticed by the speed of c ? Perhaps the force hasn't been noticed because nobody as considered a force contributing to lights momentum before ? How could anyone notice something if they aren't looking for it ?
  49. -1 points
    The reason you find or take a limit is when the values cannot give you an exact answer in an equation. Then the equation can be graphed, and the limit assumes the value that the function approaches on the graph. It is an extra step that can be taken to make a graphical analysis to find an approximate answer by looking at a graph. You can say that it is a certain value, even though the calculation of the variables in the equation cannot give you an answer. It is another way of trying to deal with infinity or infinitesimals in of itself. The main reason why this method isn't used in a lot of work is because it is not known if it has been proven to be reliable, but it has been proven to be reliable when finding the derivative. Limits can potentially give false values, presumably. I have never seen any evidence of that.
  50. -2 points
    You could try some of my experiments, why yours are better? If once done they gives rise to evidence… from a hobbys Physicist
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