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  1. 3 points
    Yes, what then? In my opinion they are intimately related. Let's take an example. Imagine a very weak photon source, emitting about one photon every minute. All around it, but at a distance of one light second (=300,000 km) we have photon detectors. Now according to Maxwell (no photons, just waves) every minute a circular wave front expands into space. According to QM however, we only have a 'probability wave', and the photon is detected at only one detector. At the moment of detection, I know immediately that none of the others will detect a photon. So the event 'measuring a photon' and 'not measuring a photon' are entangled. If behind every detector would stand a human observer, one could send a message to all the others when measuring a photon and tell them that at timepoint 5:09h she knew that nobody else had measured a photon, based on the fact that she already had measured it. So the entanglement follows directly from the wave character of the probability distribution. The power of real entanglement experiments (also known as EPR, or Bell experiments) is that we have positive measurements on both sides, not just a lack of a measurement. But they are expressions of the same phenomenon. So, what then? No. We do not need realtime measurements. If two detectors at a great distance of each other are in the same inertial frame they just can make their measurements, notice the exact time of measurement, and then later compare their measurements. There is no faster-than-light communication. See here. The mathematical theory of QM is unambiguous: entanglement must exist. Do not forget, it was theoretically derived before it also was measured. So there is no problem to solve. The only problem is that we, humans, cannot picture this based on our daily concepts.
  2. 3 points
    Well, for that last one anyway, they become POTUS.
  3. 2 points
    Hello guys, So, a lot of my time is spent reading about history, studying it, writing about it, etc. And I mean a vast majority of my time. And while I know this is a science forum, I feel that if we can have a politics section, which arguably has less to do with science and politics then it does with pure politics at this moment, it wouldn't overly hurt us to have a history section. Would anyone else agree that having a section open about history would be good as well? I mean the same basic rules could apply. You have to have evidence, you have to list sources, you can't preach, etc. Just my personal suggestion and I'm curious what other's on this forum think. I personally would love to start a discussion about Christopher Columbus.
  4. 2 points
    But the 19 century scientists didn't just accept or reject an aether. They calculated consequences according to their best Science and then proposed tests, which they carried out to the best of their ability. A real shining example of progress via the scientific method. Furthermore they knew the limits of their abiltiy. They knew that the experiments of Fizeau were against calculations carried out by neglecting higher order terms in series and so were first order. They were only able to measure the effects of higher order terms at the very end of the century. It was these later experiments that confirmed the lack of aether and lead to a search for other explanations. By the way, siecle is the French word for century.
  5. 2 points
    There was an initial assumption that if there were waves, there must be some sort of physical medium for those waves. That assumption turned out to be false. Another example of science winning over "common sense". Basically, we have detected something that we can describe using wave equations. Does that mean that mean the waves are real or just a useful description? "Physically exists" is a difficult concept that belongs in the philosophy forum. You could spend months arguing about the meaning of "physical" and then months more arguing about the meaning of "exists". When you have a 5 definitions of each, you then spend years arguing about which of those apply to the electromagnetic waves. And, if you take the quantum view, there are no waves at all. Just quanta of the underlying field. Does that field exist? Yes, because we measure its effects. No, because it is just a mathematical abstraction. It is impossible to say which of these is "true". We have new models that work. The ether model did not work. Ditto phlogiston, caloric, "plum pudding" atom, steady state universe, etc. As these models are not consistent with the evidence, they have been replaced with new models that do. I cannot understand why so many people want to go back to models that have failed. Some of them seem to have a weird romantic attraction; a sort of "steam punk science" aesthetic. Fine. But this is a science forum, not an "aesthetics of dead theories" forum. I'm not really sure how that relates to the concept of a luminiferous ether as a substance that pervades space. Obviously, many people have later used the word "ether" to describe other things: Einstein famously described spacetime as being an "ether" (because it is everywhere) much to the delight of the steam-punk pseudoscientists. They ignore the bit where he went on to point out that it could not be a material substance (ie. is not the luminiferous ether they were looking for). Others have used to word to describe one or more of the quantum fields that pervade space, etc. This is not a science discussion. It is a history of science discussion. Maybe you should go and cast a vote in the "should there be history forum" thread. I knew someone (or two people) would pick up on that. But it is important to note that the leeches are used for very different things. Which is a good analogy for the fact that wave equations can be used to describe the movement of material substances (eg. sound waves in air) but can also describe things that are have no material existence (eg. light or electrons, etc). Just because we use the same tool, doesn't mean we are clinging on to the old, discredited ideas of how things work. Let's turn this around. What reasons do you have for considering the ether? If there are reasons to accept this ether, I would also like to see that. What properties are you claiming for the ether? How is the experimental evidence consistent with those properties? What other experiments do you need?
  6. 2 points
    Or maybe not. From https://en.wikipedia.org/wiki/Hirudo_medicinalis#Today
  7. 2 points
    Alternative history and speculations are virtually the same thing. Events alone are not really historic sciences per se and biographies are a small specialization. The Schlieffenplan was an "Aufmarsch" (Deployment)- and not an operational plan. Van Moltke ran into operational and logistical challenges. The claim that von Moltke messed with a glorious plan costing certain victory was basically a myth or narrative created by German historians (and officers) to deflect blame. Only post WWII historians have started to revise that narrative, though it has stuck in high-school classes for a long time.
  8. 2 points
    It’s a lightning rod to prevent religious discussion from littering up the other science based sections. When religion was removed as a subforum in the past, biology and cosmology became where these unavoidable conversations kept landing. Better to acknowledge these conversations will occur and given them a properly quarantined home. Also, like politics, the topic is inherently interesting to many of us and it’s nice being able to explore its various intricacies with other generally rational and intelligent members here.
  9. 2 points
    I disagree that it wasn’t doing any harm, or at least that we can state such a thing with any certainty whatsoever. Neither you nor I can know that, but we have actual evidence that maybe it was, in fact, doing some harm. I’ve seen members get treated differently when other members found out they lacked a penis. Sad, but true. Examples of this are both recent and historically consistent. I also have to imagine that any LGBTQ individuals may have found the binary choice insulting and frustrating, as yet another example of a place in this world where there’s too much friction when trying to simply fit in and be ones authentic self. I believe this is what triggered the OP, which basically asked for 68 more gender choices (I’m paraphrasing). The intent was good and the hope was laudable; to be more inclusive, but following the original recommendation would’ve IMO actually added friction to the process, not reduced it. At SFN, when we submit posts, what matters is the structure of our argument and our ability to defend and support it; our ability to convince others of the veracity of our position and do so in a cordial manner. It doesn’t matter if I’m black or white, old or young, gay or straight, male or female, sick or healthy, rich or poor, fat or skinny, or anything in between. This is a merit based site, not a tribal one or one where phenotype or crotchal plumbing are in any way relevant . So, I’ll ask... if the gender option was as unimportant and harmless as you and others keep claiming, then why are so many of my fellow members getting their panties into such a twist now that the path of least resistance was chosen and gender was removed from profiles entirely? Help me understand... cuz I sure don’t get it.
  10. 2 points
    Hmm... I think something went wrong. I just glanced into my pants and suddenly I look like a Ken doll.
  11. 2 points
    And this French show (called Taratata) that requires live performance without any soundtrack, playbacks, orchestra or any other support. Lady Gaga: Poker Face et "mon français est merdique (my french is shitty).
  12. 2 points
    I'm going to post this here, it is a short video about bacteria movement and super fluids but I have seen something similar in real life. I used to culture euglena as a food source for rotifers, in the culture barrels the euglena would swim around and round the barrels and almost always they would all go the same direction actually making a visible current that would carry small floating particles on the surface around visibly moving at several inches a minute. These microscopic protists creating this current as long as the sun shone on them I think was similar to what is being said here.
  13. 2 points
    Yes. For physics, very near or perhaps at the top. (Nature and Science are probably higher, but they are multi-disciplinary) (I have a PRL on my cv. Not bad for someone who is without knowing science)
  14. 2 points
    It's not quite that simple, though. Neutrinos travel (slightly) slower than photons but are far more penetrating because they don't interact the same way. You have to look at the interaction probability as well. Alphas are more likely to interact owing to their larger charge. They will ionize surrounding atoms, which causes them to lose energy and slow down. Neutrons will tend to penetrate better than protons, because even though they have roughly the same mass, the neutron has no charge. Alphas don't. They have a pretty well-defined penetration depth. "The range of alphas of a given energy is a fairly unique quantity in a specific absorber material." https://sciencedemonstrations.fas.harvard.edu/presentations/α-β-γ-penetration-and-shielding There's a plot here of what the alpha count typically looks like with distance. https://physics.stackexchange.com/questions/308359/does-alpha-radiation-penetration-depth-decrease-exponentionaly-with-distance/308428#308428
  15. 2 points
    The transmission medium original question was air. Further alpha and beta rays are both charged and particulate. The particulate part says that it depends upon the nature of the source and the particle density. The charge says that there is interaction with airborn particles. In fact transmission through a medium usually follows an exponential decay type law. This also applies to EM radiation, but the coefficients are such that air is virtually transparent to gamma rays, over distances measured in less than hundreds of kilometers.
  16. 2 points
    It's sometimes useful to distinguish between necessary and sufficient causes of disease. So we'd say Mycobacterium tuberculosis is a necessary cause to contracting TB, but it's not a sufficient cause because, for instance, the number of bacteria might too small to overcome the host's immune response. Mental components are neither necessary nor sufficient for physical diseases to occur so the answer is no, all diseases do not start in the head. Which is not to say that one's state of mind isn't a factor, but you can't get TB without the bacteria no matter how hard you think about it.
  17. 2 points
  18. 2 points
    I'm not sure of the relevance, but I just looked at a £10 note which states "I promise to pay the bearer on demand the sum of ten pounds." If I redeem the promise at a bank I'll be given a note with "I promise to pay the bearer on demand the sum of ten pounds." Money, to governments, is basically an I.O.U. note which will never be redeemed. I don't think the idea of taking the same percentage of everyone's cash income is better than the current bad system. It would be even easier for rich people to (in effect) avoid paying tax through legal but dodgy companies or investments.
  19. 2 points
    You just have to heat it to high enough temperature..
  20. 2 points
    No it is not: "Dietary exposure to aluminum (usually as the citrate) results in small amounts of aluminum being absorbed from the gut (<1%) and reaching the bloodstream [4]. Following enteral absorption, aluminum is transported mainly in the plasma in association with the iron-binding protein transferrin [8]. Aluminum is distributed well throughout the body with the skeleton and lungs (due to inhalation exposures) containing the highest mass of aluminum (approximately 50% and 25% of the body burden, respectively). As for many divalent and polyvalent metals,the skeleton can be a longterm storage depot for aluminum, with the half-life of aluminum in bone being on the order of years [5]. It is anticipated that bone will serve as a stable depot for aluminum in infants, as well as adults, due to the increase in bone mass and volume that takes place during an infant’s rapid growth and development. With regard to the non-skeletal compartment, the half-life of aluminum in soft tissues such as the liver is short (<2 days), which indicates very little accumulation in these organs. The majority of bioavailable aluminum is excreted shortly after exposure, primarily in the urine [5], and there appears to be little difference in the renal clearance of aluminum in infants and adults at low exposures [9]. Although aluminum accumulates in the brain as well as bone over time, the concentration of aluminum in brain is lower than that in many other tissues of the body (e.g., liver, spleen), and only 1% of whole-body aluminum is present in the brain or central nervous system at any given time [8,5]" "Assuming slow release of aluminum adjuvant from the site of injection into the systemic circulation, we have demonstrated that aluminum levels in infants are well below the minimal risk level curves for either median or low-birth weight babies. We also compared the body burden of aluminum contributed by vaccines with that contributed by diet. The body burden of aluminum from vaccines is not more than 2-fold higher than that received in the diet. While the contribution of vaccines to an infant’s aluminum body burden can be slightly higher than that of the dietary contribution in our model, the fact that the primary pool where the aluminum is residing, as a long-term storage depot, is likely to be skeletal and not a more sensitive soft organ system is reassuring [5]. Although aluminum toxicosis is known to occur in humans, it is found exclusively in individuals suffering from kidney disease or in those exposed to high levels of aluminum via occupational inhalation" Source: http://vaccinepapers.org/wp-content/uploads/FDA-aluminum-paper.pdf I'm not even going to comment on this nonsense, I have too much respect for this site and I don't want to go off topic any further.
  21. 2 points
    Do you understand that the high levels of aluminium may be because of the autism, rather than the other way round? Also, let's have a look at this OK, a typical brain is about 1.4 Kg Of which, according to this https://water.usgs.gov/edu/propertyyou.html about 73% is water So it's 17% "dry weight"- whatever that may be. That's 378g of "stuff". It's mainly from the frontal lobes (Have a look at the data here https://www.quora.com/Neuroanatomy-How-much-do-the-various-parts-of-the-brain-weigh-on-average-or-approximately-what-proportion-of-the-brain-is-each-part if you don't believe me). They average about 2.3 µg/g So that's 870µg of aluminium in the brain. But a typical vaccine only contains 125µg So, unless every last drop of aluminium in a vaccine is transferred to the brain, it figures that MOST OF THE ALUMINIUM IN THE BRAIN IS FROM SOME OTHER SOURCE; THERE JUST ISN'T ENOUGH IN THE VACCINES. Also, you seem to have ignored the important bit of what I posted. Do you remember that you said "The decline in infectious diseases began before the mass use of vaccines and was rather due to the improved nutrition and sanitation. " and I pointed out that If that was true then stopping vaccinations wouldn't lead to an increase in the incidence of- and harm from- measles. But it has. When reality does not agree with your ideas, it is not because reality has got it wrong. Well, you need to address that. Good luck.
  22. 2 points
    Q-reeus and beecee have both been suspended for three days for not being able to lay off the personal jabs at each other.
  23. 2 points
    True, but irrelevant. Not always. The faster metabolism of children means that in many cases they are less susceptible to toxicity. As a case in point consider aluminium. One way in which the body can avoid damage from aluminium is to sequester it in bones. Babies and children are continuously producing more bone tissue as they grow so they are better placed than adults to trap this element harmlessly in bones. If that was true then stopping vaccinations wouldn't lead to an increase in the incidence of- and harm from- measles. But it has. When reality does not agree with your ideas, it is not because reality has got it wrong. Nobody has shown that it can. If I was the editor of that journal, I'd be embarrassed to publish something so poorly written
  24. 1 point
    They don't produce the same effect. Case A produces an electric field at some distance away, while case B does not.
  25. 1 point
    The Richard Nixon defence. I might have to report myself...
  26. 1 point
    Change can still occur by mutations or infection resulting in endosymbiosis (mitochondria, chloroplasts etc), even if isolated.
  27. 1 point
    Ad hominem isn't efficient nor effective, regardless of who it's used against. I don't see them really getting upset at it, rather than like me, simply being confused by it. If you want to do it, sure, go ahead. I just don't understand the motivation behind it. I could see it being changed if it was required, but it being an option didn't force anyone to reveal their gender. And now, if they want to reveal their gender, they simply go to the about me section and type it in, which is again an option. To me it seemed like: "We should probably remove the option to include your gender." "Why? What if I want to?" "Then you can put it in the about me section if you want." I can't help but see a certain inconsistency here. If that still doesn't clear it up, I can break it down into variables: Prior to this change: People have the option to include their gender. After this change: People have the option to include their gender. If that makes sense.
  28. 1 point
    The following is an article detailing the second man made object to reach Inter stellar space, or that region where the Sun’s flow of material and magnetic field no longer affect its surroundings. https://www.abc.net.au/news/2018-12-11/parkes-radio-telescope-tracks-nasa-spacecraft/10605106 NASA confirms Voyager 2's crossing into interstellar space as Parkes tracks its progress ABC Central West By Joanna Woodburn and Kathleen Ferguson Updated yesterday at 4:14pm PHOTO: NASA's Voyager 2 has crossed through the heliosphere into interstellar space. (Supplied: NASA ) NASA has confirmed that Voyager 2 is now in interstellar space, some 18 billion kilometres from Earth — and its progress is being tracked from central-west New South Wales. The probe, launched in 1977, is the second human-made craft ever to enter interstellar space. The first was its partner, Voyager 1, which made the crossing in 2012. Since early November the CSIRO's Parkes Radio Telescope has been tracking Voyager 2, which can no longer be observed from the northern hemisphere. more at link....... <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
  29. 1 point
    Gender information was always optional INow. I don't see the rush to remove it either, as it wasn't doing any harm. Sometimes the information adds depth to an opinion. Example... If I'm getting informed on women's reproductive rights, it would be nice to know that it is an opinion brought about by experience. Not what a man 'thinks' they should be. Simply my opinion. Information in itself is never bad; only its wrong use is. ( and that's why we have mods )
  30. 1 point
    You probably shouldn't be using it for that long. "Use of intranasal decongestants (such as oxymetazoline) for more than three days leads to tachyphylaxis of response and rebound congestion" from https://en.wikipedia.org/wiki/Tachyphylaxis#Other_examples I suggest you check with your doctor. Good point.
  31. 1 point
    I don't think so either. It's not a quantifiable thing anyway.
  32. 1 point
    Surely the pH is a measure of the acidity of the water in the soil, not the soil itself? So a pH meter will not give any sensible reading when placed in kiln dried sand. I think that some pH meters are actually a form of conductivity meter. These could obviously be confused by the presence of conductive minerals in the soil.
  33. 1 point
    2) Yes 1) Consider the relative strengths of the four fundamental forces. This table is from Wolfram Science http://scienceworld.wolfram.com/physics/FundamentalForces.html This is why gravity doesn't strip the electrons out of atoms. I think they try to keep the paths of the accelerated particles horizontal in large scale accelerators. Also there are regular repeater coils or E/S deflector plates in the installation. Perhaps someone with direct experience of these things will chip in here, especially if they have a better answer?
  34. 1 point
    Yes I agree acceleration/deceleration is the key here. Some additional points. Dropping the case and protecting against a projectile with tank armour are different scenarios. In the first it is the case and contents which are decelerated. In the second it is the projectile. So tank armour would not help here. A heavy case falling, will hit at the same speed as a light case (Galileo) but will transfer great momentum due to its mass. Therfore producing a greater impact force unless the impact time can be lengthened. So the issue might best be thought of in terms of a soft v hard case.
  35. 1 point
    A greater mass means that for a given impact (force) means it will undergo a smaller acceleration. i.e. it's a consideration for reasons other than the scenario in question. And I think acceleration is the key here. How the guitar responds to being accelerated is important, because that what causes the internal components to have stresses and strains and torsions, etc. I would think you don't want a loose fit, since that means motion within the case until the guitar hits an obstruction, and that's where damage occurs. You want snug, but in a material that has "give" to it. (padding materials generally have voids in them, so they can compress) That's why there is internal padding — it increases the time it takes to come to rest, decreasing the acceleration. A heavier case would potentially make a greater indentation into whatever it hits, which increases the time of impact, reducing the acceleration.
  36. 1 point
    I'm not sure what this last sentence means. But most people are of the view that there was some form of "chemical evolution" that eventually led to the components necessary for living cells. (Also not sure what IQ has to do with it. But welcome to the 50%!)
  37. 1 point
    Pardon the pun, but it is somewhat "case" dependant. If you dropped one onto a fairly solid piece of glass, supported by a foot or so of fibreglass insulation, a heavier case might break the glass, allowing a lot more time and distance to decelerate the guitar than a lighter one that would not break through. Now compare that to dropping them onto the same insulation supported by a concrete floor. Wasn't there a thread previously on this?
  38. 1 point
    I’m struggling with the heavy versus light distinction. Seemingly more important is rigid versus elastic, or firm versus cushioned. Based on mass alone, I’d imagine lighter is better since heavier means higher momentum upon impact (greater force being cascaded through the intricate bits of the instrument).
  39. 1 point
    If I may wade in a bit here. Both of you are somewhat correct. RTS,S/AS01 is indeed a vaccine that is toward the end of the development pipeline. It is the only one to pass Phase III and next year it will be rolled out. It is distinctly different than how we consider standard vaccines, which includes efficacy (less than 40%). It is also limited to children and infants (so it could not be used for adults going on vacation, for example). The reason why it is being used at all, is essentially due to the massive risk of malaria, coupled with a complete lack of alternatives. I.e. one could consider it a an emergency vaccine of sorts. Also, it is only available within a pilot project in selected areas in Africa where Phase IV will be conducted.
  40. 1 point
    Nope. Plenty are triggered elsewhere https://en.wikipedia.org/wiki/List_of_human_hormones So, you are basing your idea on something that's known not to be true. You can stop now.
  41. 1 point
    Maybe you need to study the basics of economics, then you would know that the fatal flaw in this argument is.
  42. 1 point
    Tri-atomic molecules can stretch and bend, or waggle, in such a way (asymmetrically) as to "resonate" with infrared wavelengths. Di-atomic molecules can't move in such a way, always constrained to move symmetrically. Search: co2 vibrational modes animation. I know there are you tubes of Prof. Denning, doing his 'waggle dance' showing how CO2 absorbs heat, using his head as the carbon and his upraised fists as the oxygen. Or just search 'infrared CO2 waggle' online. “The symmetric stretch is not infrared active, and so this vibration is not observed in the infrared spectrum of CO2.” ~
  43. 1 point
    I'd like to think that I'd behave kindly towards the "lilliputians". It costs me practically nothing to do so. I suspect I'd end up worshipped as a God anyway unless they were fairly sophisticated. It's not as if it would be hard for me to help them with major construction work (from their perspective- or sandcastles and dolls' houses from mine). The only "payment" I could expect would be the satisfaction of my curiosity (and maybe a bit of help with splinters etc). Who knows- I might get them to make me a diffraction grating. The tricky bits would be communication and also avoiding accidents. I'd clearly need to sleep somewhere else. Even an ill-timed sneeze would be a problem.
  44. 1 point
    Here you are: https://en.oxforddictionaries.com/grammar/countable-nouns This is oxforddictionaries, is that authentic enough for you?
  45. 1 point
    Maybe it has some answers, but not all? Maybe not all scientists agree all the time on all points? Maybe you still have to figure out what scientists know, and you think you know too, but it's far from the truth? Buzz off. Did I spell that right for you?
  46. 1 point
    What advantages.. ? Trigonometric functions are extremely slow to calculate (by CPU/FPU)... sqrt(x) is just generalization of power of x^0.5 cube root(x) is just generalization of power of x^0.3333333(3) ps. Make function that is calculating something faster than currently existing methods, and you will have attention from scientific community, and more importantly from computer designer community (faster operation is always welcome by programmers and users of applications). You need to benchmark currently existing methods and you own method to verify your method is faster than native, and alternative implementations.
  47. 1 point
    Tidal and Hydro power are surely an underutilised resource: https://www.independent.co.uk/environment/scotland-floating-turbine-tidal-power-record-sr2000-scotrenewables-ofgem-a8503221.html With the reliability of tides, you would presume that more countries would be investing heavily and rapidly in this technology.
  48. 1 point
    The method is sort of interesting, but useless. Not quite that far. My dad knows how to do it and he was born in the 30s It seems the manual method is still available. https://xlinux.nist.gov/dads/HTML/squareRoot.html
  49. 1 point
    Meanwhile Trump being congratulated at the G20 on his "historic victory" in the midterms by Japanese Prime Minister Shinzo Abe. Apparently he must have read the title of this thread and looked no further into it...
  50. 1 point
    Here, we agree. But here your position is confusing. We know Russia actively worked to elect Trump. You seem to be saying Clinton colluded with them in these efforts, efforts intended to defeat her. You’re saying she actively worked to secure her own defeat. You then claim that the evidence of this is how her team paid a US company to do opposition research, and that company hired a British fellow, and that British fellow got some information from people who were from Russia, and those Russian folks suggested our current president was videotaped while prostitutes peed on him. That’s your evidence of this. Even if your point that Clinton sought to undermine democracy itself due to her fury over Trumps push for her deleted emails (which strains credulity, but I’ll stipulate it), the evidence you cite in no way supports or begins to scale with this claim. Your position is confusing, but more than that it’s defective.