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Showing content with the highest reputation since 07/07/20 in Posts

  1. 5 points
    The 'bowling ball on a rubber sheet' is a two dimensional reduction of a 4 dimensional configuration. It has multiple problems, one of which is that you can observe it from an embedding third dimension. Space-time has no embedding dimension; both the bowling ball and you, the observer, would need to be intrinsic to the rubber sheet ( i.e. also two dimensional ). A three dimensional representation would already get rid of some problems, but not all. Picture a three dimensional grid, where x, y, and z axis divide up the space into cubic elements. A mass placed in this space would curve the x, y, and z lines such that the elements are moreskewed, and smaller, as you get closer to the mass. That is 'space' curvature, and one aspect of gravity, but already much harder to visualize than the two dimensional example of the bowling ball/rubber sheet. Actual gravity is four dimensional 'curvature' of space-time, and I can't help you visualize that as it is impossible. Some problems are just not suited to visualization, but understanding even just the basics of the math goes a long way to clarifying things.
  2. 3 points
    That's word salad. Science - physics especially - quantifies effects. It's not enough to spout some technical jargon. One needs a mathematical model that predicts behavior. Any notion that gravity can be replaced by electrostatics is trivially debunked, because there's no way to get an always-attractive force between more than two bodies. We orbit the sun, sure, but the moon orbits us while orbiting the sun. Pick a charge for the sun and the earth, and from the known orbits, mathematically deduce the charge on the moon that consistent with the known orbits, the tides we observe on the earth, etc. The effort will fail once it's approached with a bit of rigor.
  3. 3 points
  4. 3 points
    I don’t think this is a good way to look at it at all, and it is also not what the formalism of QM actually says. If the particle did pass through both slits simultaneously (according to who’s notion of simultaneity?), then you should be able to show this by simply bringing the detection screen close enough to the slits. But no matter how close the screen is, you always get exactly one hit, never two. Crucially, you also don’t get an interference pattern from a single particle - you get a only a single hit on the screen, as one would expect. It is only when you have an ensemble of many individual hits, that you will observe them to be distributed as an interference pattern. So the crucial aspect here is not that it goes through both slits simultaneously (a highly dubious and ill-defined concept), but that there is no information available about which slit it went through; and since the respective probability distributions are wave-like, an ensemble of many successive hits will give an interference pattern. Conversely, if you amend the setup so that it can tell you which of the slits the particle goes through (and you will find it will always go through exactly one slit, and one slit only), then the interference pattern disappears, because there is now certainty about the state of the system, and thus no longer a basis for any interference. So the central concept here is superposition, and thus the availability of information. A superposition does not mean that somehow two states physically occur simultaneously; it’s rather more subtle than that. Even the very notion of the particle taking any trajectory at all between emitter and screen is no longer a trivial thing.
  5. 3 points
    Sure why not? Mathematically, instead of having quantities that change with respect to some time coordinate, you can always have quantities that change with respect to one another, without reference to any notion of time. ‘Change’ doesn’t imply time, and time doesn’t imply change. Derivatives (in the calculus sense) with respect to some quantity other than time are well defined and commonly used. For example, imagine you have a purely 3D universe, without time, that contains a tea cup. The handle of the cup has a certain curvature; the interior surface of the cup also has curvature, which is probably numerically different. So the surface curvature changes with respect to spatial coordinates, rather than time. So you have a universe that encompasses changes, but no time. This is perfectly consistent and valid, at least in my mind
  6. 3 points
    These are questions that have kept Western philosophy busy for the past few millennia, and there are as many opinions on it as there are philosophers. My own thoughts on this are (currently) that all we can observe are objects of consciousness - we do not have observational access to anything else. The thing with this is that all objects of consciousness are mental constructs - hence everything we can observe has been pre-processed by the mind in some way. Assuming that there is such a thing as an external reality on which what the mind presents us with is based (I am making no claims whether or not there is), then the big question becomes how the mental model we observe maps to external reality. How accurately does it reflect external reality, and which parts of the model have ontological status, and which parts are ‘merely’ phenomenological? At the very least the model will be extensively filtered and incomplete, since it can only be based on our own limited sensory apparatus (meaning some other sentient being with different sensory apparatus will construct a model of the world that may be fundamentally different from our own). It will also be subject to all manner of distortions and biases, since the way the mind interprets sense data is necessarily based on memory and prior experience; we never get “just reality”, but only some reflection of it plus the mind’s own running commentary, so to speak. The most crucial question, so far as it connects to the discipline of physics, is what kind of ontological status - if any at all - the various fundamental categories have which the mind uses to structure this model. By this I mean things like spatial and temporal relationships, object-subject dualities, etc etc. For example, are space and time really attributes of external reality, or they just categories the mind uses to construct a suitable model of the world? What about the fact the very ideas of ‘observer’, ‘observed’, ‘reality’, ‘mind’,...are all themselves mental constructs? These are tough questions, but I think it is important to ask them, because it may turn out that things really aren’t the way they initially appear to be. Our scientific models may say just as much about the structure of our minds as they do about the ‘external’ world. And then of course there is the question of whether such a thing as an ‘external world’ actually exists, in what sense it can or cannot exist, and if/how we could find out. I have personally started out on my own journey as a staunch ‘scientific realist’, but I am finding myself growing increasingly doubtful of this. I think it may be a mistake to try to eliminate all reference to our experience of the world, because such a thing as ‘objective reality’ and its description may ultimately be a meaningless concept. This doesn’t mean that science is on the wrong track, but its domain of applicability may be limited in ways that we are failing to account for as of yet.
  7. 3 points
    I will not attempt to answer that particular 'why', but I will offer you a plausible explanation as to why your thoughts have been generally dismissed by other forum members. In no particular order: You have failed to provide a concise and coherent explanation of your proposal. You have made many assertions, but have offered no meaningful support for those assertions. Your posts have seemed belligerent, discourteous and at times hysterical You have not been attentive to replies Your proposals may have much value and even be the correct way forward, however emotional rants will never be as effective as rational argument. I recommend organising your thoughts, presenting them in a simple, straightforward manner, and toning down on the patronising agression. Of course, if you don't really want to convince anyone, then keep doing what you are doing.
  8. 3 points
    @IDoNotCare Sorry if you're feeling attacked but you need to be able to summarize(and no I'm not a sock puppet). Nobody can read minds here. I might hazard a guess that you're talking about a post scarcity society and more specifically 'fully automated luxury communism', but you need to spell that out. Without a good reason to, nobody wants to sit through a bunch of YouTube videos or go offsite to a random link. In some cases there is just an initial investment hump that automation has to be pushed over. Admittedly communist countries also tend to nationalize simultaneously, which is a great way to kill outside investment. I think we'll at least see automated trucks. For long-hauls along a highway it would be simple enough. Even if legally they end up needing a truck tender, you could find someone cheaper than a full time driver. At it's heart most R&D boils down to an optimization problem, so algorithms can work for some things. We might still need either a person or possibly a well trained AI, to define problem constraints. I don't think work will be truly eliminated but it might be more of what people actually like or want to dedicate themselves to.
  9. 3 points
    Well, I'll be damned. One wave of the hand, and 5+ billion of us, who just happened to be born into non-Christian cultures, sentenced to burn in hell for all eternity. Makes me wonder just which of those two guys to blame, really.
  10. 2 points
    You did not make an attempt to define crime. What is or is not a crime varies by locality. That said there are studies that look at the impact exposure to violence (many forms of violence are criminal throughout the world) has on the brain as it develops. Exposing a child to violence does impact brain development, increases adult health risks, and increase the likelihood the child with be violent. Witnessing domestic violence as a child limits said child's attachment to parents and is associated with lower IQ. HERE Another study links violence exposure at a young age to inflammatory issues than lead to increased health risks from cardiovascular disease, type-2 diabetes, and dementia, HERE And of course exposure to violence at a child increase ones likelihood of being incarcerated as an adult. HERE. In some country it is a crime to be gay. Throughout much of the world until recently it was a crime to marry someone outside ones race. There are and or have been crimes against premarital intercourse, drawing images of God, etc, etc, etc. I would imagine for each type of crime much debate could be had about whether or not chemical imbalances at a play and whether or not medical is appropriate or could be success in altering the behavior. That is why a specific definition is need for crime. Does merely labeling something a crime reduce empathy for said behavior? Look at addiction. In the U.S. it is legal to drink Alcohol. As such society is fairly tolerate of people with varying degrees of Alcoholism. Provided one gets treated being an alcoholic doesn't hold one back from opportunities (employment, financing, security clearances, etc) Yet here is the U.S. narcotics are illegal. A history of narcotics addiction will hold one back from opportunity.
  11. 2 points
    ! Moderator Note It wouldn’t explain this, but you need to understand some physics to see why. I am feeling less generous than Strange. All WAG, no science. Speculation needs some foundation in science.
  12. 2 points
    The bicycle rider has to measure the speed of light as being c, relative to himself, regardless of what direction he is traveling. So let's say, that when he is ( by his measure) 1 light hr from a source that he has been moving away from at 0.5 c. That means that the light reaching him from that source at that moment had to leave the source when they were closer together, when they were only 2/3 of a light hour apart. Thus it took the light just 2/3 of a hour to reach him, during which time the source traveled 1/3 of a light hour. to a distance of 1 light hour. Further assume that that light carried an image of a clock at the source reading 12:00. Since he knows that 2/3 of any hr passed since that image left, and that due to time dilation, The source clock runs 0.886 times as fast as his own, the source clock should read between 12:34 and 12:35, at the moment he sees this light. Now let's say that he is moving towards the source at 0.5c, when he sees the light while still 1 light from the source. Now he has to conclude that the source was further than 1 light hr away when the light left ( 2 light hrs away). He still has to measure the light as traveling at c relative to himself, So, by his clock it took 2 hrs for the light to reach him, during which time he and the source closed to a distance of 1 light hr. He sees the same image of 12:00 for the source clock*, But he now it has been two hrs since that image left the source, during which time the source clock advanced to read 13:44, which is the time on the source clock when he sees the image This is quite a bit later than what he concluded when he was moving away from the clock. So before the bicycle reverses direction, he would say that is 12:34 on the source clock, and afterwards he would say that it reads 13:44 ( even though the image he sees for the source clock remains 12:00) For this we assume an instantaneous change in velocity, which can't actually happen. The bicycle has to spent some non-zero time accelerating, during which period it is non-inertial. It is a bit more complicated to work out what someone concludes when working from a non-inertial frame. For one thing, it is only the Local proper speed of light that is measured as being c. The "coordinate" speed of light changes with distance from the observer. So said observer cannot conclude that the light traveling from the source traveled at c relative to him for the entire trip. The upshot is that for this accelerating observer, clocks in the direction of the acceleration, run fast by a rate that depends on the magnitude of the acceleration and the distance to the clock. This leads our bike rider to conclude that while he decelerates to a stop and then accelerates back up to speed back towards the source, the source clock runs very fast and ticks off the time between 12:34-12:35 and 13:44, over a very short period by the bike rider's clock. * If it helps, assume two bicycles, one moving towards and one moving away from the source and passing each other when they are 1 light year away from the source. They both need to see the same image of the source at that moment.
  13. 2 points
    I too am a lucid dreamer. I too have had dreams where people and or places in my dreams have established histories. So this topic is potentially interesting me. However I think it should be couched within understand the basic premise. It is too huge of a leap to connect it with evolution and what not in advance of understanding anything about it. Assuming you believe your own mind creates the entirety of your dreams how and or why do you think it creates backstories within dreams?
  14. 2 points
    See, told you a written source would be better. 😃 If it described it with great clarity, you wouldn't have needed to ask the question 🤨
  15. 2 points
    That provides a good start to my thoughts. The stated purpose of this thread is to examine the Physics of the question "What is Time ?" One way to do this is to go through the properties of time and see where that leads. Many entities are well describe by their properties in Physics. We could also ask questions like Is time a property of something ? Is time a coordinate in a coordinate system? If so, what if we do not have a coordinate system? What processes does time allow that cannot occur without time? Starting with coordinate systems. Sketch 1 shows a block universe, including time. I have only included 2 spactial dimensions (height and breadth) to be able to easily draw it. Since I have 2 spatial dimensions they permit areas so I can think about such concepts as pressure, magnetic flux density etc, and in conjunction with time processes such as magnetic induction. But there is a twist, depending upon how we regard the times, past present and future. In a block universe is 'time' Omar Khyam's moving finger that moves through the block universe as a temporal plane called the present ? If so it is like the focusing device of a scanner. Yet this temporal plane occupies zero duration (length) in time and its coordinate axes are purely spatial (height and breadth) So what happens if we are the past and future are inaccessible and throw them away ? We are left with plane that has no time. I have shown this idea in sketch 3 and a similar one operating on one of the spatial dimensions (height) in sketch 2. What else do we do with coordinate systems ? Well we look for invariants so we can transform them. So how about the ultimate transformation, doing away with the coordinate system alltogether ? In Minkowski space the invariant is the interval, symbol S, treating each axes as equivalent, but using Markus sign system. Each point in a Minkowski space is called an event and I have picked 4 of them and labelled them A, B C and D. Again for ease of drawing I have reduced the space this time to one temporal and one spatial axis. Sketch4 shows the result. Each event has an invariant interval to every other event in the space. The network formed by all these invariants will be the same in all coordinate systems, by definition. So we can throw away the coordinate system - We don't need it, all the information is contained in the table of S values, presented conveniently in matrix format at the bottom. So do we need an axis called time?
  16. 2 points
    No there is no change in this picture. You posted it 18 hours ago and it hasn't changed a bit. There are 2 colors (B&W).
  17. 2 points
    I think I may venture a reason why the teacup example has proven to be so controversial: Human-made objects are generally designed with the hope that they last unchanged for as long as possible*. So you can go back to the handle, the spout, or whatever part and find it exactly the way it was before, except for a scratch or a slight discolouration. Consider, OTOH, the example of a metamorphosing insect somewhere along the causal line: egg, larva, caterpillar, pupa, butterfly. It's almost impossible to look at a caterpillar without picturing in your mind the butterfly to be that it represents: Our experience of the past deeply affects our thinking, and I would go on to say that in many cases leads us to some kind of circular-time representation space. This is the realm of inductive thinking. Laws that seem to suggest cycling and re-cycling in continually perpetuating process seeding and re-seeding. Cosmology imposes on us to stretch the concept of time to its very limits: Eternal inflation, accelerated expansion, thermal death. It's so tempting to try to make sense of time in this difficult context that many models try to embed them in some kind of cyclic time, which is the one we're so familiar with. Collapsing and recollapsing universes, multiverses, etc. The caterpillar-pupa-butterfly kind of universe. I may have got all of you completely wrong, but it seems to me that those who are closer to seeing time as an aspect of thinking that's so intrinsically hardwired in our brains that sort of impregnates everything we think, are: @Markus Hanke, @michel123456 , @MigL, and myself. I'm not so sure about @Eise, @geordief, @studiot, @The victorious truther, and @vexspits. Seems to me like they are more inquiring about other people's views. In particular, whether we identify time with any kind of differentiation. To the risk of misrepresenting them, I would say they're interested but not convinced. Then there's the "hardliners" if you will, represented by @Phi for All, @Strange, and @StringJunky who, to the risk of oversimplifying their views, go more like: I don't see what the problem is, what's soooo special about time. Time is just a factual aspect of physics. Get over it. Then there's @iNow, who seems to line up with "us", the puzzled-by-time bunch, by quoting Sagan. This is not to say that within these groups everyone agrees with everyone else. And again, I'm not sure whether I've represented you faithfully. Please, feel free to correct me. --------------------- * Planned obsolescence aside
  18. 2 points
    Never thought I'd see the day that third world countries, banana republics and military dictatorships have to send observers to the USA to verify that the current President doesn't try to pull a fast one in the upcoming election. And the way he's mis-handling the Coronavirus pandemic, waiting until it is safe to have an American election, would effectively make him President for life.
  19. 2 points
    “Trump floats election ‘delay’ amid reports the economy underwent an historic and unprecedented contraction” See also: “Child kills parents, demands mercy because he’s an orphan“
  20. 2 points
    This is just more shitflooding. Sew doubts in order to eat away at consensus. Say unreasonable things to dumbfound your opponents, and claim everything they say is fake. He's simply corrupt, immoral, ignorant, and the worst person possible for the position. These are the tactics of corrupt and ruthless businessmen. We may not think much of politicians, but this is one thing they (normally) would never do in the US.
  21. 2 points
    He doesn't have the authority to move the election; presumably he knows that. But this announcement has done a marvelous job of distracting people from the latest economic figures. He may also be setting the stage for claiming that the election result is wrong and he should stay on... forever.
  22. 2 points
    As long as you just look at a teacup, or a graph of a function, I fully agree with you. I would say, yes, you do it, and time is the parametrisation you use. In my opinion, if somebody says that 'y changes as function of the change of x', she is saying 'if you change x from a to b, then y changes according f(a) to f(b)'. But a change of x is an activity of an observer, and observers exist in time. And concerning your points with MigL: of course change can occur without observers. But observing a change means either a passive observer sees things changing (you are sitting quietly at a veranda, and you see the streets changing from dry to wet (a very common experience in Ireland...)) or you look at an non-changing object, but you let wander your gaze from one place of the object to another, and e.g. see how the colour 'changes' dependent on the place of the object where you look. But the latter also means a change in time. But the change is in the observer, not in the object. The object is static.
  23. 2 points
    Isn't systems collapsing by themselves a big problem in quantum computing? It doesn't depend only on an observer right? It collapses by itself all the time. Awesome that they were able to maintain superposition of a 2000 atom system for 7 ms.
  24. 2 points
    Buckyballs. (C60, i.e. a kind of soccer ball with 60 C atoms). And even more: But the experiments are difficult, because even the tiniest disturbance would destroy the superposition.
  25. 2 points
    Disgusting. You’re dead to me now /throwing up in my own mouth
  26. 2 points
    ! Moderator Note You aren't allowed to call the things you make up "facts". Do it again while you're discussing anything here and you'll be suspended. You might want to consider going to a less rigorous science discussion forum if you want claims like this to pass unchallenged. Thread closed.
  27. 2 points
    Even if you don't progress much further than now, you've done very well for being self-taught and your ability to relate what you know is excellent.
  28. 2 points
    I think everyone is always responsible for their actions. Whether or not they should be answerable for them is another matter - it essentially boils down to the question of how much choice someone actually had in a given situation. Someone’s social environment, upbringing, mental disposition etc may place strong constraints on their behavioural patterns, so they may not have been as free to choose their actions as we’d think. But then again, this is very difficult to measure objectively, because on the flip side you have plenty of people from extremely difficult backgrounds who are not prone to criminal behaviour at all. So I don’t know what the answer is, but it can’t be a simple one.
  29. 2 points
    Nope that is not how it would work. For the most part organisms do not know what adaptations are going to work (and even with extensive research it can be difficult to tell). Rather what happens is that the conditions the organisms live in create so-called selective pressures. What it basically means is that certain genetic traits are more likely to reproduce than others. But different pressures can have different strengths. So let's say lack of sunlight is a strong pressure. Also assume that folks with more melanin (i.e. who are darker) produce less vitamin D are are prone to vitamin D deficiency. What fist needs to happen is that there are either already folks with lighter skin in the population or that at some point mutants arise with lighter skin. Let's further assume that this make folks less likely to reproduce so mutants with less melanin may be more successful in reproduction and over many generations the pool will be dominated by them. However, unless the selection is super strong, there is likely always going to be a mix. If a population is relatively homogeneous, more often than not another aspect is important, the so-called bottleneck effect. This is when there is a small starting population where drift can play a large effect, resulting in small population with low genetic diversity. This is one of the reasons why in Africa we have a large genetic variability compared to Europeans. On top of it there are other random effects which have nothing to do with geography. For example if a in a population no mutations for blue eyes occur (which is basically traced to a mutation in a single gene), there will never be blue-eyed folks.
  30. 2 points
    I can't believe I'm defending an anti-evolution stance, but you're strawmanning their argument. The part they disagree with is natural selection leading to a change in species over time, not that traits are passed along without reproduction. You're making their argument too simple in order to discredit it, and that's using a fallacy to support your own argument. Most anti-evolution arguments acknowledge what they call "microevolution", where children share traits from their parents. They just don't believe natural selection can account for a complete change in species. Anybody who is looking only at their own life and reproduction isn't addressing evolutionary concerns. Natural selection is one way to change allele frequencies within a population over time.
  31. 2 points
    The star TYC 8998-760-1 (top center) was photographed with two giant exoplanets (arrows), the first time astronomers have directly imaged more than one planet orbiting a sunlike star. The bright spots above star TYC 8998-760-1 are other stars in the background. BOHN ET AL/ESO https://www.sciencenews.org/article/first-picture-sun-like-star-multiple-exoplanets-astronomy-planets
  32. 2 points
    Actually the most likely scenario are neutral mutations. In most species there is a large space where mutations happen, but nothing changes on the physiological level. In viruses and other condensed genomes mutations are more likely to have an effect. But due to the high production rates many deleterious mutations are not observed as they do not get transmitted or even out of host cells in the first place (e.g. if the particle is not fully formed). Those that have been monitored so far are, again, mostly neutral, though the latest research indicate a potential new mutation that could be more effective in transmission (though not validated yet). While this often happens, it is over a longer time. What basically happens is that if a less harmful strain emerges in parallel with a deadlier one, over time there is a certain likelihood that the deadlier version spreads slower (as its host keeps dying). After a certain while, the less harmful one may become dominant. However, especially in this case it may take much longer, as the death rate is not terribly high and especially among folks that are very good at spreading (i.e. younger folks) the symptoms are relatively mild. There is evidence that there are long-term damages to the lung, even among those that recover, but that is unlikely to be detrimental to its spread. Wait what? First time I have seen that. Is there an article about that that you could share? Edit: Looks like one of those viral social media thingies. I.e. more rumors than anything https://www.snopes.com/fact-check/people-collapsing-coronavirus/ Those things add confusion to the current situation which is not really ideal.
  33. 2 points
    This is actually not very difficult to conceive in principle within the quantum formalism. Quite more difficult is to give a precise and detailed answer. As Eise has told you, a quantum particle, in some sense, sniffs around all of space time. When you see it in a mathematical formula printed on a paper, you see very clearly it doesn't look like the whim of a god. It does look like a precise mathematical pattern of evolution. Now, this evolution, in a quantum theory that includes special relativity, is very puzzling, among other things, in that it includes modes of propagation that are superluminal, subluminal, every which way. Those are called "virtual amplitudes", and they appear in the calculations, although they cannot be measured. They are called "off-shell". The basic reason for this is actually a peculiarity of relativistic kinematics. A real photon satisfies a condition or reality that has the form, \[k^{2}=0\] k is called 4-momentum, and codifies the direction in space-time in which the photon is moving. It's a combination of 4 numbers, the time component and the 3 spacial components: \[k^{2}=\left(k^{t}\right)^{2}-\left(k^{x}\right)^{2}-\left(k^{y}\right)^{2}-\left(k^{z}\right)^{2}\] So it could be negative, positive, or zero in general. Real photons are null. For real photons this quantity must be zero. But you can always decompose this "real" state as made up by the real components plus many other virtual ones, \[k^{2}=\left(k+p\right)^{2}\] These virtual ones have momentum ("direction") p, which is not physical, and in particular could be superluminal or subluminal: \[p^{2}>0\] \[p^{2}<0\] as long as they give you a real photon: \[0=k^{2}+p^{2}+2kp\] I haven't shown you the full-fledged argument in quantum field theory, which goes with amplitudes and so-called Dyson time-ordered formula, but a simplified version of it. It is by no means a foolproof explanation. But here's my question for you: Can you guarantee that the positions where the particle can or cannot land (the not-so-well-known partial reflection paradox is another interesting example) are not set in advance by all the components of the quantum state, including the virtual ones, that make up the Feynman propagation formula?
  34. 2 points
    Now that is an example of bad philosophy... And a pretty good example of my present disclaimer: With other words: what you say is a philosophical remark. E.g. it is based on the assumption that only empirical facts matter in life. But that itself is not an empirically verified position, so, according to you, it distracts from true knowledge. Your position is self-refuting. As to the question of the poll: of course there is good and bad philosophy. But we should keep Strange's distinction in mind: 'philosophy' as a 'philosophical theory', i.e. the contents of what a philosopher is saying about the subject at hand; and 'philosophy' as an activity. Which of course agrees more or less with the same distinction in science. Good philosophy, in modern times: Is well informed about relevant science, culture and politics Takes into account other viewpoints about the topic at hand Confirms or refutes other viewpoints with good arguments, i.e. arguments that are relevant and well supported by sciences and other well argued philosophical viewpoints Is extremely aware of the methods it uses to argue for a certain position. Bad philosophy: Only expresses opinions without arguing Uses arguments that are already refuted by others Confuses scientific speculations with philosophy The specialty with philosophy which distinguishes it from sciences is that in science the domain of knowledge it tries to gather differs from the (transcendental...) subject (i.e the one that observes, experiments, and expresses ideas about the object) of the domain. A physicist investigating certain phenomena does not investigate herself. As I said elsewhere here, the object of physics is not physics: it is the natural world as we observe it. As soon as physicists investigate physics, they are philosophising. Philosophy is essential reflective: it tries to understand our thinking with thinking, just as the physicist thinking about physics.
  35. 2 points
    So you made one up. I think you need to get back to that point of view, and then learn the science. Eise has given an excellent short summary. If you want more detail, then I recommend Feynman's lectures to a non-technical audience on QED. He explains how this works, extremely well: http://www.vega.org.uk/video/subseries/8 (Also available as a book, if you are old-fashioned like me.) There is no communication. It can be shown that this idea does not match experimental results (see Bell's Theorem) From the title: This is what is known as the logical fallacy of begging the question: you start with the (non-scientific) assumption that a god exists, then add the assumption that it controls every photons, from there you derive the conclusion that quantum theory proves that a god exists that controls every photon.
  36. 2 points
    The great African Rift Valley has been known about for hundreds of years, and stretches from the Middle East to below the 'horn' of Somalia. It is actually separating three plates; The Nubian plate, which is most of Africa, is receding from the Arabian plate, across the Red Sea and Gulf of Aden, fairly quickly, while the Eastern sliver of Africa, including Somalia's horn, is receding much slower. The separation seems to be subject to 'spurts' of activity, as this latest trench opened up in 2005. It will still take millions of years for a sea to separate the two parts of Africa.
  37. 2 points
    To be fair, we know that the effect of sunlight is almost entirely the effect of UV. Virus particles are essentially made of proteins and DNA or RNA. None of those absorbs visible light so viruses can't be affected by visible light. It won't even warm them up much since it will be scattered or reflected. So, you can discount the roughly 90% of sunlight that isn't UV*. Which makes the heating problem roughly 10 times less bad than you think. It's also likely that most of the "killing" is done by UVB rather than UVA, in which case you can include another factor of 20. In that case, the thermal load from the UV needed to get a good kill quickly is roughly the same as sunlight. Which is all very well, but a hair drier is probably easier. * Based on Most of the natural UV light people encounter comes from the sun. However, only about 10 percent of sunlight is UV, and only about one-third of this penetrates the atmosphere to reach the ground, according to the National Toxicology Program (NTP). Of the solar UV energy that reaches the equator, 95 percent is UVA and 5 percent is UVB. From https://www.livescience.com/50326-what-is-ultraviolet-light.html#:~:text=However%2C only about 10 percent,and 5 percent is UVB.
  38. 2 points
    OK, I'll re-phrase. In every other normal, or sane, country in the world, if you are carrying a weapon, you intend to do harm to others ( or yourself ). In the US, where you are Constitutionally enabled to carry military assault weapons into grocery stores, banks, or even churches, I guess that rule doesn't apply. And you defend that right, making a police officer's choice either getting harmed ( or shot at ) while 'talking', or shooting first, asking questions later, and possibly going to jail for having made the wrong choice. Policing in the US is becoming untenable; I'm surprised you can find people who want to do the job. ( and possibly a reason why you get people like D Chauvin ) Carry-on, I'm going back to vacationing ...
  39. 2 points
    https://medicalxpress.com/news/2020-07-rna-reversing-mutations-underlying-neurological.html?fbclid=IwAR38JE4SGPC-ODBqRzTmdpenmcsLHHiSbfUa63rZhH42UFk0Lfxg-qPd5vI This sounds to me like a piece of very interesting news. Possibilities of editing RNA is a topic that fascinates me, although I still have to learn a lot about it.
  40. 2 points
    God's word is "asshole"?!?!
  41. 2 points
    This is a genuine sub sub branch of Pure Mathematics which is very obscure. Try reading this Wikipedia has a simple offering for once https://en.wikipedia.org/wiki/Limited_principle_of_omniscience Then read a full blooded paper from Birmingham University https://www.cs.bham.ac.uk/~mhe/papers/omniscient-journal-revised.pdf Avoid the religious books by Paul Tranter They are not connected. https://books.google.co.uk/books?id=I8bKDwAAQBAJ&pg=PA69&source=gbs_selected_pages&cad=2#v=onepage&q&f=false
  42. 2 points
    Because physicist don't bother, as long a they have perfect operational definitions of time. The question 'What is time?' is, as already remarked, a philosophical question. Not a question about physics. I think even you have no problem to understand what the traffic sign '50 km/h' means. Really, physicists have no problem with their 'dx/dt', or whatever changes according to t. And there are already several threads about time, and I think most of them in the philosophy-forum, where it belongs.
  43. 2 points
    Can we please just agree that the risk from knives is not equivalent to the risk from firearms and move on from this silly tangent? Yes. Not perfect, but much better
  44. 2 points
    This is a wise choice. You can display even more wisdom if you remain an active member of the board, but focus -at first - on asking questions, rather than making wild speculations. They can be great fun, but they are not the best way of learning about,, or conducting, science. I look forward to reading more of your posts, but ones that ask interesting questions. Cheers.
  45. 2 points
    I am going to withdraw my theory. I had decided to quit, The theory doesn't seems to be logical, Sorry. There by I declare that the discussion based on this topic has come to end
  46. 2 points
    “We will automate everything” is a pipe dream. 1. For processes where it was cheaper to automate, it would have already happened. 2. Some things we are trying to automate and are finding that it’s very hard (see:self-driving cars) 3. Things like R&D will likely never be automated Also, if you want to propose communism, you need to not only draw a path of how to get there, but also how you will avoid the catastrophes observed in previous attempts
  47. 2 points
    ! Moderator Note Please refrain from using personal insults, even in response to inane accusations/posts. I know at least one of your sockpuppets is better than this. ! Moderator Note If you want to argue, please do so without insulting people. Also, stating opinion as facts is not a good argument, it is soapboxing. If you want to make specific arguments, make them here and structure them in a way that allows a discussion. If all you want to say is visit this website and if you do not agree with me, I am going to throw insults, then this is not the right place for you.
  48. 2 points
    He launched yet another weapon of mass distraction
  49. 2 points
    I agree that the OP definition is not quite right, but both your A and B examples have two errors. Yes a zero error is a systematic error but it is not due to a wrongly marked or non uniform graduation and yes it can result in an increased or decreased actual measurement. A simple example of a zero error would be dirt on the pan of an otherwise accurate weighing scale.
  50. 2 points
    Hi Ahmet, just some thoughts... Very (extremely) few people achieve to live from music. Even less as a composer. You better make software: easier, well paid, many jobs. Violin professors have hundreds of students in their career, one is more talented and trains seriously, and becomes her or himself a professor. Sometimes, this exceptional student is even more exceptional and earns his living by playing music rather than teaching it. These are the orchestra musicians. Soloists are even much rarer, composers too. How many composers does a concert need? Presently, Covid-19 is an absolute disaster for all performing arts. No concerts, or concerts without public, meaning less incomes for the orchestra. Most musicians are not on the permanent payroll, so they get no engagement at all. Playing on the street is presently no-no in many countries. Youtube brings zilch to standard musicians. Romania is a fantastic place to hear music. But to play it? People from Romania and Moldova go to Germany and Austria to live from music. What kind of music? A few people manage to live from folkloric / cigani / klezmer / etc music. That could work better than classical music. It's often not a first choice. Illenyi Katica, Rusanda Panfili... are all excellent classical musicians who jumped into folkloric music to make a living. Or do you mean songs for the TV?
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