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  1. 5 points
    Element 115 (moscovium) has a half life of about half a second, so is not very practical as a target. https://en.wikipedia.org/wiki/Moscovium (And I doubt that element 116 can be produced by firing protons at the nucleus.) "Immediately decays"? It is true that the half life of livermorium is less than that of mosocvium; but it is not immediate. Livermorium decays via alpha decay. In other words, it emits a helium nucleus (a pair of protons and a pair of neutrons bound together). https://en.wikipedia.org/wiki/Livermorium It does not emit anti-protons. That would violate all sorts of conservation laws. https://en.wikipedia.org/wiki/Conservation_law And anyway, what would be the point? This can only be of interest to people who think that antimatter=magic. What are you going to do with these anti-protons? Presumably combine them with some protons to generate energy. But you can't get any more energy out of that than you put in. So the whole process of accelerating some protons, transmuting 115 to 116, then capturing the anti-protons and then generating some protons for them to interact with, then controlling their interaction and directing the energy ... all takes energy. And must run at less than 100% efficiency. https://en.wikipedia.org/wiki/Laws_of_thermodynamics So you are going to get less energy out than just using shooting the original protons out the back of the rocket. Or using the heat from the rapid decay of the moscovium (you will be left with no useful fuel after a few minutes, anyway). There is nothing to critique here. This is just meaningless word-salad from a bad SF book. No references here because there is no such thing as "Gravity-A waves", "Gravity B waves" or "Gravity Amplifiers". Also, gravitational waves (which do exist) are not directly related to gravity. Gravitational attraction is not a wave phenomenon. Also, gravity is only attractive; there is no practical or theoretical reason to think that somehow causing gravitational waves (if that is what the ignorant author means) to interfere would cause any gravitational effect (either pull or push). Gravitational waves cause stress (stretching and shrinking) in directions orthogonal to their direction of travel. This effect is too small to be significant, unless you are a few miles from two merging back holes. https://en.wikipedia.org/wiki/Gravitational_wave Gravity waves are something completely different. They are a phenomenon in fluid dynamics and have nothing to do with gravity (in the sense implied here; they are caused by gravity, not a cause of gravity). https://en.wikipedia.org/wiki/Gravity_wave It is almost as if the author doesn't know what they are talking about. And are just stringing together a bunch of words they don't understand. See anyone can do it.
  2. 4 points
    After 8 seconds it said "This film is not presented as fact." So I did not watch the rest. Correct. I am not interested. But if anyone provides reliable scientific evidence about progress in our understanding of gravity (and/or anti gravity) I would be very interested. Warning: Straw man ahead: *) Replace alien technology with "magic", "psychic powers", "spirits", "life after death". The scientific content would be the same (zero).
  3. 4 points
  4. 4 points
    Note that the spread was predominantly along trade routes. While there is decent evidence supporting the use of (black plague) bodies (which, btw. were already spreading in Asia and the Middle East), the entry of the plague was likely independent of that (or it may have contributed it, but was not the major driver). The narrative of the use of cadavers and the spread of the bubonic plague to Europe following the the siege of Caffa was strongly based on the account by Gabriele de' Mussi. Historians disagree whether he was actually physically present during the siege, but it appears that they think it is at least plausible that cadavers were hurled into the city. There is also the possibility that the plague arrived with the army and was subsequent transmitted by rodents, but despite overall uncertainties it is (from what I have read) not the favoured explanation. In the accounts de' Mussi also said that those escaped from Caffa were bound to Genoa Venice and so on and thereby spread the disease. However that clashes with what I think is now fairly well established understanding how the plague spread into Europe. It is well established that the plague spread over the Crimea, but cases in Genoa and Venice appeared well over 2 years after the siege of Caffa. Since even under unfavourable conditions the voyage should have not taken more than a few months, the timeline does not line up well. Another aspect that even if that timeline would have worked out, the time required would still have resulted in a substantial outbreak on the ships themselves. But again, around that time, there were no records of something that must have been considered to be a significant event. There are also folks who dispute that corpses were used in the first place (as there are no reports from folks fleeing from Caffa describing it aside from de' Mussi's account) or that there is no indication that it was knowingly used as a bioweapon (some dispute that bodies would be effective, they should have flung rats instead...). There is for example the speculation that the plague may have entered Caffa via the waterways. The Mongols were not able to fully block those and this where Caffa was getting resupplied. Also historians report that a step-wise entry of the plague into Europe is more likely which makes a spread over trade routes via Crimean ports even more likely. Well established reports pinpoint spring 1347 as the start of the plague in Constantinople, for example. I.e. there are quite a few reports that contradict the strong narrative of warfare-mediated spread, which is quite fascinating actually as not only historians have been working on it, but also epidemiologists and microbiologist, who use the documents to establish timelines and spread, not dissimilar to modern epi-studies (just with scarcer data). What is rather neat is that a fairly recent PNAS paper actually described genome evolution in Yersinia pestis which is consistent with repeated introduction via migratory and trading routes.
  5. 4 points
    The plot revolves around a group of highly trained professionals who break into homes of elderly folks and aggressively cough into their faces for a few minutes. In a heartwarming twist one of their presumptuous victims confuses the terrorist with their grandchild to whom she had lost contact. After a furious intermezzo consisting of baking and copious amount tea the terrorist realizes that deep inside he is just longing for the love of a family. Meanwhile the grandparent realizes that the nightly visitor in stealth suit is indeed not her grandchild (the climbing hook on the balcony being a crucial hint- as well as a flashback highlight that the real grandchild had a fear of heights). But she enjoys the moment too much to care.Tragically, this human moment is also what ultimately resulted in successful infection. The terrorist becomes guilt-ridden when it becomes clear that the lonely grandma is not long for this world and he tries to reach her a last time to say his farewells. Meanwhile, his terrorist buddies consider him a traitor and try to stop him resulting in a highly choreographed fight scene involving lots of offensive coughing and running noses in slow-mo (the filmmakers did not consult experts as per usual and did not realize that this is not part of the symptoms). Finally, he survives all these ordeals and reaches the grandma, who turns out to be a special CDC/Homeland security agent in disguise (Jason Stratham) who have been delaying a rollout of coronavirus testing in favour of sting operations to catch corona-terrorists. PS: can anyone tell that I really, really do not want to read those student reports?
  6. 3 points
    We have already detected gravitational waves. However, neither gravitational or magnetic attraction is mediated by waves. A "magnetic wave", is just one component of an electromagnetic wave, or in other words, light and radio waves. Magnetism, as in the attraction and repulsion of magnets, is due to a field, not a wave.
  7. 3 points
    I shared that the Bible cannot be the source of morality since our existing morals allow us to pick and choose which parts of it are right and which parts are wrong. John reinforced this point in his own way. You suggested we were saying “what’s the point of books if we already know stuff.” I corrected you. That wasn’t the point. Our point was specific to the assertion that morals come from the Bible. You then made yet another different point, that we know before we learn. Sounds fancy, but is obviously both nonsense AND not what was being suggested by me or John. You told me I could explain better, so voila... see above. Hope this helps and hope we can now please for the love of Thor get back on topic instead of chasing fortune cookie one-liners from an unsober but otherwise easy going and enjoyable poster. ✌️
  8. 3 points
    I don't have Covid 19! test came back negative! Looks like just plain old viral pneumonia! That 104 fever was a bitch! Feeling better now! All I need now is a flight back to NC, CA is nice but home is nicer!
  9. 3 points
    It's not intuitive. Another one not intuitive to me is cold bleach, it seems, bleaches better than warm or hot bleach. Edit: Lower concentration increases contact time so that the surface of the microorganisms protein coat is not denatured too quickly such that it prevents more of the alcohol penetrating deeper into them. Superficial denaturing may just initiate dormancy.
  10. 3 points
    Do you mean that because, in this case, it has no free will, in normal circumstance it does? @ others: I can’t moderate in this thread but there is no reason to suddenly get irrational and offensive just because someone mentions the “R word”. Grow up
  11. 2 points
    Maybe some lie, maybe some don't really understand their own feelings, maybe being attracted to the same gender and getting excited by watching other men and having sex are not the same? Just because someone feels excited watching something, doesn't mean they are instantly INTO that thing, in the real world. There is a large difference between reacting to seeing something, and doing it yourself. Although there probably is a subgroup of people that may not know they are homosexual/bisexual, or they feel moral disgust due to stigma/upbringing and therefore say they aren't sexually attracted? So many reasons.
  12. 2 points
    That's one aspect of a social species. You're trying to say this is representative of all evolution, and that's extrapolating in the wrong direction. You can't go from specific to general based on one data point. To quote from The Logician: 'All wood burns,' states Sir Bedevere. 'Therefore,' he concludes, 'all that burns is wood.' This is, of course, pure bulls**t. Universal affirmatives can only be partially converted: all of Alma Cogan is dead, but only some of the class of dead people are Alma Cogan. IOW, all social behavior is the result of evolution, but not all of evolution deals with social interaction
  13. 2 points
    And even in conventional electricity, the net flow of electrons is slow. The current is caused by the massive numbers of charge carriers, and the fact that the interaction proceeds at the speed of light in the material. But the electrons themselves have a drft velocity far, far slower. To have electricity you need free charge carriers, and that's typically the electrons. You could do this with other charged particles, but you'd have to create a condition where they are the free charge carriers, and that just doesn't happen except in very specific circumstances. The fact that electrons are stable and much less massive than protons, and don't bind to other particles except via the electromagnetic interaction (unlike protons binding to neutrons and other protons) is the reason they are free to create currents in conductors.
  14. 2 points
    Well, we already had plenty that did not originate there (as well as a few pandemics) and we will have plenty of outbreaks within the next few years. It is mostly the confluence of factors that make a disease more likely become a pandemic, which includes e.g. effective human-human transmission, long incubation time, late/difficult detection, outbreak in areas with high connections to rest of the world etc. This time a lot of folks dropped the ball which resulted in a rather unprecedented situation. The question is whether the next one (which will come) will be contained better or not.
  15. 2 points
    I think it's human nature to blame something about oneself that can't be changed for ones lack of progress in some aspect. I gave my deafness more weight than it deserved, in hindsight.
  16. 2 points
    ! Moderator Note Discussion has that advantage, certainly, but only when one listens rather than lectures. Unfortunately, you aren't discussing this, so nobody is learning anything they really need to. Discussion would mean you actually incorporate comments from others in your replies. Instead we see an outlined lecture series you obviously don't want any critique on. Please go elsewhere to do this kind of blogging. Nobody is interested in that format here. This is a science discussion forum. Thread closed.
  17. 2 points
    Don't worry, patience is not an issue, at least not in my case. But I think the forum rules still apply, you can't keep blogging and hope for questions to self-resolve in some distant future. I have reread the posts so far and I can't find that my questions are adressed. The addition of doppler in the last revision does not add clarification regarding issues raised earlier. Basic question: Can you please post the complete set of postulates used in your "related experiments"-idea? There is no need to repeat the whole "fresh look" stuff, just tell the postulates and, if necessary, how they deviate from the postulates used in SR. What you have posted so far does seem to match SR predictions, it is not a "fresh look" of SR and it is not an alternative point of view of SR. In my opinion clearly stating the postulates you use and how your postulates differ from SR may help bring the discussion forward. Since you state that SR is an offshoot of Electromagnetic Theory I guess that your postulates must differ from SR in some way; when deriving certain relativistic effects from your postulates we see how electromagnetism comes into play in some way that deviates from the mainstream SR.
  18. 2 points
    You are free to defend this in a thread in speculations You mean like stuff you posted in the other thread? That I debunked?
  19. 2 points
    The entire Neil Young archives free for streaming. https://neilyoungarchives.com/info-card?track=t1975_1129_01
  20. 2 points
    So there is a preprint that predicts about 80k deaths in the USA over the next 4 months with large uncertainties, though (MEDRXIV/2020/043752). See also https://www.reuters.com/video/?videoId=OVC6U1U23&jwsource=cl Edit: If true, it be more deaths than the deaths attributed to influenza (at least since 2010).
  21. 2 points
    I think there may a couple of wrong assumptions but I am not read enough in those areas to provide an immediate in-depth response. Let's talk about zoonotic diseases first. One thing of note is that at high population densities and contacts with animals there is a higher likelihood of a pathogen crossing species barriers. But even then they may not cause large outbreaks, as they may have low transmission or low virulence and either exist invisibly in a given population or do otherwise do not garner a lot of traction. Many viruses re-assort in pigs transfer to humans and then change further (e.g. by grabbing genes from other viruses in their hosts) before they cause outbreaks. Take the H1N1pdm09 (swine-flu) pandemic, for example. That particular strain has a bit of a mosaic structure, probably originating from three parental pig viruses and emerged into humans somewhere in North America, some assume in Mexico. There is also the MERS epidemic, that came likely from camels but were sufficiently contained not to cause an epidemic. Hantavirus is a deadly virus that has a case fatality of ca. 40%. However, it is spread by mice and not human to human (luckily) and was found in the USA. There are also plenty of zoonotic diseases found in India, such NIpah virus and has been slowly spreading. However as there is no human-human transmission the spread is not as rapid. Likewise, we had a Zika pandemic not so long ago, a mosquito borne disease, originating from Africa. Japanese encephalitis likely originated in the Indonesia-Malaysia region and while it is also transmitted by mosquitos, it causes outbreaks every couple of years with about 13-20 thousand deaths each year. Again, lucky break that they need mosquitos as vectors. So in a way to me the question is whether it is by chance that those originating from China have larger impact on global health and economy or whether there are factors contributing to it. I think one needs to think beyond sanitary issues, as you mentioned. One question could be for example how connected China is compared to India. But also for example how the meat industry looks like. Another perhaps simple question is also what types of potential zoonotic diseases are there that could for example mix with animals that come into close contact with humans. In India many are mosquito borne, but perhaps they are less relevant in China. In Europe and US industrial pig farming has a huge potential to recombine and spread viruses in pigs, but there are perhaps fewer animals around that can spread novel viruses into pigs. Regulating or closing those market can likely close some of the risk factors. However, ultimately my thinking is that the world is shrinking, for better or for worse. There will be more contact between each of us and there are diseases that not zoonotic. What it means is that otherwise local disease have a much easier to become epidemic and even pandemic. Without the willingness for rapid responses to detect human-human spread, I think that most of the measures will be insufficient. And I think it is somewhat wrong to think that in the Western world our measures will keep us safe indefinitely. We had prion disease entering the food chain (sure it is not an infectious disease per se, but still). Farm animals often have to be culled due to various disease outbreaks. So far those have not managed to jump the species barrier, but it is not something that may so forever. On the other hand of course there is the tendency of diseases to become less virulent over time (as killing the host is generally not a good long-term strategy) but in the meantime a lot of harm can be done. Other man-made reasons for outbreak are for example anti-vaccination campaigns. HIV/AIDS now is well controlled, and we get complacent again (in the 90s it was for a time the leading cause of death in young adults). We have tons of pathogens that can mix, mutate and while there may be area with larger reservoirs than others, I do think it is dangerous to think it as an "elsewhere" problem. I think this is what lead to complacency when China was facing COVID-19 and that is why despite ample warnings the Western world only reacted when they had deaths in their midst. It may not be quite what you are thinking of, but I do think that this change in mentality is necessary to combat the inevitable occurrence and re-occurrence of diseases (and I apologize for all the typo and rantiness, it is more flow of thoughts without proper editing, may try to express it clearer when I got time again). Edit: had so many unfinished thoughts but wanted to include that global warming is going to increase the likelihood of many, especially mosquito borne diseases, so that has to go in there also somewhere.
  22. 2 points
    To amplify Mordred's statement ( +1 ) Mathematically and logically a relation is a particular conncetion between pairs of (mathematical) objects. Equality as represented by the equals sign = is characterised by three properties. Where A B and C are three mathematical objects 1) Reflexivity A = A 2) Symmmetry If A = B then B = A 3) Transitivity If A = B and B = C then A = C These may seem obvious but they are fundamnetal and very important. Another stronger reelation is identity. This is different from equality and should be carefully distinguished. All identities are also equalities, but not all equalities are identities. An easy way to see this is to compare the following [math]{x^2} - 1 \equiv \left( {x + 1} \right)\left( {x - 1} \right)[/math] This is an identity. Note the different symbol. It is true for all x or each and every possible value of x. But [math]{x^2} - 1 = 0[/math] is only an equality. It is only true for certain values of x and not true for many more. To pick up on the remark about chemical equations. You noted that chemical reactions represent a process as well as an equality (mass balance charge balance etc) These are more properly shown with various arrows for this reason [math] \to [/math] etc
  23. 2 points
    Again it doesn't count as a dimension. It is a relation not a dimension.
  24. 2 points
    Will you please tell me which other forums you post on? If you see Charon as typical, then I’d very much like to go visit them. They sound wonderful!
  25. 2 points
  26. 2 points
    Good article here: https://www.bbc.com/news/health-51963486
  27. 2 points
    I'm picturing this like a Western: you standing on a deserted street with the spray clipped to your belt. Arms by your side, fingers twitching slightly. Suddenly a figure emerges from a bar and prepares to spit on the floor. Before he can move you have drawn and fired sprayed. Nice animation showing the how big the effect of reducing contact is: This also applies to increasing herd immunity (because that also breaks the chain of transmission). So as herd immunity increases, the limitations on social contact can be reduced.
  28. 2 points
    Worse, it is less effective at higher concentrations.
  29. 2 points
    Directly in an equivalent common English phrase, it probably means "It is what is and we can't change it"... C'est ce que c'est et on ne peut pas le changer (from Google Translate). Ours is an expression of resignation. We usually just say "It is what it is"
  30. 2 points
    Actually my wife and I have discussed this. Fortunately for us we can add some distance if only one of us is infected. Our plan is: - The sick person stays in the lower level of our home which has its own bedroom, bathroom, kitchen sink, microwave, television, and door to the outside. - Well person stays upstairs and takes care of all animals and supplies cooked food. - Ill person does their own dishes. - Luckily for us I found a handful of N95 masks in my workshop. - Hope like hell that sick person doesn't need care, otherwise entire plan might go to hell in a handcart (which is an appropriate phrase as its origin comes from hauling the dead off the streets of London in handcarts to protect horses during the plague.)
  31. 2 points
    I think it is important to understand that the risks are minimal, additionally the risks, of YOU having a phone, on your family, was not researched. I suppose it is up to everyone to minimise risk the way they see fit, however from a pragmatic standpoint you could do more harm than good (if you would not allow your family/kids to have a phone); imagine that not having a phone could be stressful when children grow up due to most other ones having a phone. This stress will have detrimental effects on their development, and may induce changes in diet which could have more effects on their health than having allowed them a phone. Not saying that this IS what happens/would happen, but it is important to think through all the possible effects. The risk, if it exists, is tiny (significant is often misused, a change from 10.000.000 10.000.001 can be significant, if we test a lot (lets say 100000000000000 times). Significance says something about the statistical likelihood (it is not just 'randomness', although that does play a role). In my opinion, this type of reaction seems to making life needlessly difficult, with people having a harder time to reach you, which may affect them in detrimental ways. But it is of course up to you. I would personally focus on diet and other things which have more meaningful impacts. Probably not eating meat, not drinking alcohol, not smoking, making sure you exercise daily (but again not too much), making sure you do things which make you happy and reducing stress for you and your family can be much more meaningful. It is very admirable that you want to protect your family (like everyone should), but one could ponder where to draw the line. You say it is not practical to be without car, which definitely could be the case (depending on your location, job and other things), but is your car super eco-friendly? Do you reduce carbon emissions as much as possible to keep your family's future as healthy as possible (I don't mean these as got-ya's, but to indicate potential things that may have much more impact than not having a phone (which in my opinion could be much more detrimental to your life than the small benefits you gain.)). Note that there is of course the additional argument (against (smart)phones)) that having a phone could lead to more internet-addiction and less attention spans, but there again, one should weigh ALL the possibilities before haphazardly changing their lifestyles. It remains good to be aware of possible dangers, but please note that stress and not being happy (= decreased happiness) have real and larger impacts on your life than the possible increase in glioma. -Dagl
  32. 2 points
    Sorry, dimreepr, but most of the times I am missing concreteness in your reactions. I discovered that when I react to possible interpretations of vague arguments or questions I have to write a long reply, then I get another short reaction that at one side seems to show that I interpreted you wrong, and at the other side forces me to write another long reply, etc. And then you react you do not have the time/energy/intention to read long texts... If the topic interests you, I would suggest to illustrate your questions or arguments with examples, preferably taken from real life, that can give your reactions the clearness for a fruitful discussion. It is true, iNow and me are trained in scientific, resp philosophical discourse, and so we can meet (and cross swords...) on a pretty abstract level. But that in itself is not a sign of intelligence, it just means we are used to the words (I hesitate to write '.. and concepts ...'), and ways of thinking. But abstract thinking can also hide a lot of differences and nuances. Therefore I often ask for concrete, real life examples. If an abstract concept really means something to a speaker, shows itself if the person can still make the connection with concrete life. And that also reduces the chances that two people use the same word, but think different things by it.
  33. 2 points
    This sounds like the poisoned drinks problem. Unfortunately it won't work here. In the idealised case where we there is say, exactly 1 in every 100 people infected then it could apply. But for every 100 hundred people we take there is no guarantee of the number of infected people. Sometimes there are none. Most times there will be one. Occasionally there will be 10. It is a random variable itself. Also, the tests themselves have a number of false positives and false negatives which will likely be significant.
  34. 2 points
  35. 2 points
    Quarks have the same status within the Standard Model as all the other fundamental building blocks - whether you detect them with particle-like properties or with wave-like properties depends solely on your experimental setup. This is not an ontological question (the nature of the entity is either one or the other, or both, or neither), but an epistemological one - what can the experimenter know about the system in question? What information about the system is made available through a specific, given setup? So essentially, whether something appears as a wave or a particle is more an expression of the relationship between the quantum system and the observer, than it is a statement of the nature of the entity itself. This is true for all of the particles within the Standard Model.
  36. 2 points
    Somewhat too simplistic to be helpful? Perhaps I'm being a hypochondriac, but I'm rather concerned that every time I run for a bus in inclement weather I come down with all the symptoms of coronavirus.
  37. 2 points
    We can go that way. I had been thinking a comedic level of incompetence, where the protagonists inadvertently infect the people at the top of the terrorist organization, and think that drinking Corona beer (it’s the Corona virus, dude!) makes them more dangerous They fail to kill anyone at their target, which is supposed to be an old folks home but they end up at a military base with a similar name (they’re drunk on Corona), and nobody dies because they salute rather than shake hands and are young and healthy.
  38. 2 points
    Well, if you wanted to actually kill someone with the coronavirus you'd have to try to sneak into homes for the elderly to be efficient. Assuming you get in contact with 100 folks above 80 you may have caused somewhere between 8-14 fatalities. You could contribute to overall spread, but if it is already spreading as it is now, it is unclear whether it would amount to more. But to do so, you will have to spend significant time with each person as casual contact seems to inefficient. So in other words you may have made the situation worse, but it is unclear how much you contributed. That, is typically just the opposite of what most lone wolf types have in mind. Part of their motivation is some distorted desire for notoriety and striking fear into folks. A "regular" mass shooting or other attack is likely to be more satisfying to them. On top, this is only likely going to work during an ongoing outbreak as there is a decent likelihood for vaccines eventually and/or most folks will develop immunity (due to infection). So all they are doing is accelerating things perhaps a little bit. Perhaps worse than any of that, poor public health responses are likely to create more fatalities than any level of deliberate act of terrorism is going to achieve. Think about that for a minute. Let's say hypothetically that testing for the virus is going to cost more than you can afford and you have the choice between going to work or lose the job, what do yo do? You cannot self-quarantine since you live paycheck to paycheck and have no food stocked up because of that. How many are in that situation compared to say ten deliberate spreaders? Now combine that with a slow roll out of tests even if they are affordable.
  39. 2 points
    I suggest we stop the bickering and petty downvoting and return to the topic.
  40. 2 points
    Observers not in line with the laser will not see the photons, unless the photons scatter off of something (e.g. dust). The number of photons in the beam is large but not infinite (and can be found knowing the wavelength and power)
  41. 2 points
    Sure JC, but maybe Phi is on to something... Some purposes, or objectives, may be more important than monetary rewards. In the case of war, freedom from oppression is the reward. In the case of exercise, good health is the reward. In the case of raising your kids, strong familial bonds are the reward. That's what I like about this forum, we all have blinders to some degree, but other members can help you see where you may not have looked previously.
  42. 2 points
    For one thing you keep insisting on 'motion' through the spatial and temporal dimensions. If you take relativity seriously, there is no space, and there is no time; only space-time, as the two cannot be separated. The argument is that you can neither move through time, nor move through space, but you are at ALL locations you occupy in space-time. In a simplified case, as you used, where we consider only two dimensions, displacement horizontally and duration vertically, you exist as a line through space-time. Vertical if you are standing still, with a slope if you undergo a displacement. And if your axis are marked in seconds and kilometers, the slope of this line can never be less than 1/300000. IOW you CANNOT move only in space. In this example, 'now' is a point on the line, and differs for every observer; that point, 'now' is what each of us perceives to be moving, through space-time. I can't really explain the 4dimensional equivalent, but you exist as a volume, 'extruded' through a fourth orthogonal time dimension, and your 'now' is a hypersurface or 'foliation' of the space-time manifold, and again, none are common to differing observers. You are trying to understand 'motion' through time, and inventing all these complexities, much like the 'add-ons' to the Ptolemaic System in its later years before Copernicus replaced it, to try and explain things which are not even required. Take Occam's razor and cut away everything that isn't needed.
  43. 2 points
    is thread has given me an opportunity to focus/confirm my thoughts on Socialism ( thanks INow ). And why B Sanders should not be considered the 'boogey man' by Republicans and Democrats alike Both Socialism and Capitalism have a use and, if not corrupted ( big IF ), can be beneficial for society. Capitalism gives everyone the opportunity to care for themselves. Socialism gives society the opportunity to take care of everyone equally. It would seem that a mix of the two allows for people to better themselves, while ensuring that no-one is left behind
  44. 2 points
    OK, so one of them is run by a mad dictator and.. Oh never mind.
  45. 2 points
    This has nothing to do with there being “no such thing as people.” The core issue here is identity, social cohesion, and empathy. Leaving aside the mystical woo of oneness, we really are just one element of the universe in human form for a little while. When we see ourselves as separate or different, we act accordingly. We become tribal, competitive, amd less cooperative. When we see ourselves as part of a larger whole, however, we see others as extensions of ourselves and tend more to protect and nourish them much like we would our own family.
  46. 2 points
    At first reading I assumed he meant electron/positron pairs had positive/negative masses, and stopped reading. Turns out he's actually implying the direction of a vector potential makes it positive or negative absolute value, not just convention. And again I stopped reading...
  47. 2 points
    I'm not convinced. I don't think being forgetful whilst talking, especially in public, is a definite sign of cognitive decline. That video is nothing more than a blooper reel. And Walker Bragman is a journalist and cartoonist not a neurologist. Not what I would call a credible source of information.
  48. 2 points
    Isn't it the other way around? What we observe in nature is the weird looking stuff. And QM is the, or at least one, explanation for it? I do not see how you can take the observations that we make about the universe to not reasonably represent how the universe is.
  49. 2 points
    Sigh no you have to recognize that harmonic, inharmonic and anharmonic are descriptives of the characteristics of the oscillator. Here is how classical harmonic oscillator is described. A simple harmonic oscillator is a sinusoidal oscillations about the equilibrium point, with a constant amplitude and a constant frequency (which does not depend on the amplitude). https://en.m.wikipedia.org/wiki/Harmonic_oscillator Note what stays constant An anharmonic oscillator n classical mechanics, anharmonicity is the deviation of a system from being a harmonic oscillator. An oscillator that is not oscillating in harmonic motion is known as an anharmonic oscillator where the system can be approximated to a harmonic oscillator and the anharmonicity can be calculated using perturbation theory. If the anharmonicity is large, then other numerical techniques have to be used https://en.m.wikipedia.org/wiki/Anharmonicity Note this oscillator deviates from the harmonic oscillator. Now see the examples they provide for each on the restoring force ? Now the quantum harmonic oscillator is the Spring example as opposed to the pendulum example. The first example the restoring force is a linear function. However it is also a symmetric linear function which can be described by the inner product. The inner of two vectors returns a scalar Ie magnitude. So the momentum in the spring is described by linear functions. The latter case the vectors are curvilinear the force follows a spinor rather than a vector. In this case you also require the direction so you would need the cross product of the vector. This is antisymmetric The pendulum example requires angular momentum equations which are not linear. You need to understand this to start being able to identify when a ratio of change is symmetric or antisymmetric in wavefunctions. Don't worry about inharmonic functions for now let's get this clear first. Edit this also a vital key to understanding the Maxwell equations as well as GR. As its applicable to all physics models
  50. 2 points
    You seem to have posted all this before and been told several times that modern authors have streamlined the presentation of Relativity over the now more than a century since inception. Mordred and Marcus in particular ( +1) have tried to point to presentations that contains earlier and simpler theory as limiting cases so the theory of Newton and Galileo is a limiting case of the Special Theory which in turn is a limiting case of the General theory. We would expect this type of progression to continue wiht future developments. Here is a mid 1960s version that demonstrates this, due to Wangsness. You should take away with you this development along with the clear exposition of how it relates to Lorenz and modern versions of the two postulates of SR The math is not too difficult. But he does provide proper reasoning for each step taken (not always shown in shallow modern treatments). I will just post the basic bit here, but he goes on in similar vein to eplore all the aspects of SR, inlcuding the electromagnetic ones.
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