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Showing content with the highest reputation on 02/11/19 in all areas

  1. I do not see any contradiction, as you seem see to imply by your using of 'yet'. Bell like experiments show that at least one presumption has to go: determinism or locality. And even if you would choose locality, it doesn't give a you a practical method to make exact predictions of e.g. where a photon exactly will arrive. Note my use of 'exact': it doesn't mean 'all of nature is indeterministic'. It means that at very small scales, where one observes single quantum particles, it is not determined exactly where or when an event will take place. But QM makes very good statistical predictions: the interference pattern in the double split experiment can be calculated with very high precision. I (male) can only remember that I referred to consensus under antiquity historians. But refresh my mind, if you want. And I am pretty sure I never said that 'all scientists believe in indeterminism'. The only backup I saw from you were articles about interesting hypotheses, not established science. For the rest, I do not understand why you react this way on Phi-for-All's post. His post was about you redefining words, not about arguments pro or contra determinism. And I do not understand at all why you come with this on a question of text interpretation. Because that is all the thread is about.
    2 points
  2. I couldn't make your algebra consistent. What for instance happened to r2 in your equation 1? Please demonstrate a proper algebraic chain of reasoning.
    2 points
  3. This is an opinion piece written by a Conservative. No polling data, stats, historical context, or etc. Just Elaina Plott's opinion about Democrats. Elaina Plott's other works include "I was a Teenage Ann Coulter Fangirl!" If you are getting your opinions about centrist U.S. policies from Conservative columnist who grew up idolizing to Hannity, O'Reilly, and etc it is no surprise you don't believe there are moderates in the Democratic Party. Have I once insulted your intelligence or wasted your time by linking an op-ed written by a partisan staff writer? I have linked data with sourced research not B.S. written by partisan idiots. I assume you are smart enough to know the difference between opinion pieces and population data. I would appreciate it if you paid me the same respect and not link fluff conservative propaganda. Based on what? Trump currently enjoys an 88% approval among those who identify as Republican. That is a better approval among Republicans than Reagan or H.W Bush had 2yrs in. It is also a better approval than Obama or Clinton had among Democrats, Gallup Poll . I don't see a single sign that Trump base will collapse. Trump was at 89% among Republicans when inaugurated and now 2yrs later he is still right there.
    2 points
  4. What if it was a laser instead? Granted, keeping the beam from spreading really wide over distance would be a challenge, but you could get the spot to move along faster the light if you had a rotating laser source projecting the beam at a far enough distance. And technically I suppose, that no individual photons are exceeding c. Not sure if there would be a practical application though.
    1 point
  5. The rod will bend, and then break, long before you got anywhere close to c. One of the implications of relativity is that there is no such thing as an infinitely rigid material.
    1 point
  6. ! Moderator Note That's not a criterion in the decision. We don't actually know what is being downloaded, and we also have a rule about links. See rule 2.7 (and I have a feeling I have pointed this out before) ! Moderator Note Nothing strange about moving non-mainstream material to the speculations section. Quite the opposite. Given that there is but one equation, and the symmetry of the situation, this only shows that you have done the calculations incorrectly. It would be like claiming that addition is not commutative, because of some result you have obtained on your calculator. GPS works, for starters.
    1 point
  7. What if you built a really long pole in space, say 1,000,000 km. Then you attached one one of the pole to a massive motor that could rotate the pole at 3 rpm. That would result in the end of the pole moving at 314,000 km/sec, almost 5% faster then c. From an engineering standpoint, this is hugely far fetched. Maybe 2 poles with the motor in the center for balance. Course you would need to attach it to the moon or something for the motor to push against. And even a small amount of gravity would bend such a bar. We probably need to discover adamantium or something to prevent that. Never mind, this was a stupid idea and would never work.
    1 point
  8. There are many many reputable links listing the facts and evidence verifying both SR and GR, beyond any reasonable doubt. The fact that they are still overwhelmingly supported by mainstream science also supports that premise. No, I have not checked your link as yet.
    1 point
  9. Doesn't the photons travel at speed c? You'll have a hard time boarding the spaceship unless you already have some other mechanism for achieving relativistic speeds?
    1 point
  10. Have you investigated the effect of a magnetic field upon photons? If so what effect did you find?
    1 point
  11. I think it has something to do with the make up of the fluid itself. Being either polar or non-polar. Water, being a polar molecule, would be more attractive to the glass surface. This would produce a concave shape. And because you are looking for the waters volume I believe, do not quote me on this, that due to this affect you would need to measure taking this into account. As for the color liquids I am not sure. An idea would be that most color liquids used in chemistry are usually non-polar. Again I am not sure.
    1 point
  12. Yes and no. Of course one can take the standpoint that humans are natural too, but there is a at least one clear difference between natural selection and artificial selection, namely that with breeding people have a goal. Nature has no goals. And further I see no problem with this kind of syntagms (new word of the day...). It should be clear and possibly unambiguous what is meant, and I think the way that the concept of 'natural selection' is embedded in the theory of evolution, is clear and unambiguous enough.
    1 point
  13. Neither of those is quite correct, INow. It is neither a construct, nor does entropy always increase with time. And while we can measure time, or differences in time, Stringy, it is the only dimension where we are 'fixed' in the present, or 'now'. Everyone's 'now' ( there is no universal now , only a local approximation ) proceeds at the same rate in their own frame. 'Now' is the only co-ordinate of this dimension we can interact with. Other differences include the ability to 'remember' the past, or previous co-ordinates, but not future ones. IOW, while different from spatial dimensions, it is nonetheless, real.
    1 point
  14. If you can measure it, it's real.
    1 point
  15. This is one of the trickier questions that is asked by everyone (literally that takes the time to understand relativity). What is the physics behind time dilation ie What causes time dilation ? This may be expressed in numerous ways and some rather unusual methods, however it is one of the more difficult concepts to grasp. So I will endeavour to supply a Heuristic explanation. As you know in Newton's laws of inertia we have a key set of relations, the 3 laws of inertia. Now many new to relativity posters commonly think these laws have been superseded by relativity which is incorrect. In truth those laws are fundamental to understanding time dilation and how time dilation works. Now I am often heard stressing the importance of paying attention to the definitions. This situation is one of the main reasons I do so. You've probably know that mass is involved with regards to time dilation. The two types of mass we are interested in is inertial mass and gravitational mass. However the common mistake is forgetting that mass in physics is defined as " Resistance to inertia change " as per those three laws I mentioned earlier. Another key definition often missed is that energy is "ability to perform work " Now if you think about those two definitions this will give you a more accurate picture of the equation [latex] E=mc^2[/latex] put into a direct English translation. "The ability to perform work is directly proportional to the objects resistance to inertia change multiplied by the square of constant c." Now we have two types of mass that you described above. You have the observer on earth and the observer in a spacecraft. Each has a different type of mass. Gravitational mass and inertial mass. Each form of mass is a measure of resistance to inertia change however the causes is different in so far as which type of energy supplies the work to supply the resistance. ( for this I will apply the term potential energy to the gravitational mass terms and kinetic energy to inertial mass terms ). Now we need to examine another key term " Spacetime ". This is distinct from our 3d Galilean view of volume, in so far as we add a variable time dimension. so now our familiar 3d universe is now a 4d universe. [latex]{x,y,z}\rightarrow {ct,x,y,z}[/latex] where the ct coordinate gives us a unit of vector length. This places it on the same playing field as the vectors commonly learn in classical trigonometry. However another feature of importance is in defining an interval. Spacetime curvature I will get into later. Now here is where we get into the term inertial frames, in SR the primary transformations involve inertial reference frames. Now lets carefully define what is an inertial frame. As per the above it is a frame where the events are at constant velocity ie freefall. There is no acceleration in either magnitude or direction. As per the laws of inertia above. It is also a frame where our vector mathematics work as per the Galilean transforms. If you have acceleration we must account for this in other ways in gauge symmetry terms a rotation called rapidity, suffice it to say additional calculations. Ok so far ? lets hope so and push on to why I stressed the above. we can simplify the above by another key relation under relativity "the equivalence principle" [latex] m_g=m_i [/latex] gravitational mass is equivalent to the inertial mass. So now we can put all this together. In the case of gravitational mass the location (potential energy In physics, is the energy held by an object because of its position relative to other objects". ) in this case the observer on Earth compared to the location of the spaceship. However what does this energy describe in this case ? well it describes the ability to perform work in terms of the binding energy at that location. The mass term at that location describes the locations ability to resist inertia change. If were are describing multiple locations in roughly the same potential we can define this under spacetime coordinates. (spacetime field). When conditions are similar enough that Newtons laws apply without significant time dilation we can use our everyday vector addition we grew up with ie Pythagoras theory without adding any additional terms or ratios of change. The resistance due to mass directly affects the time coordinate in terms of the interval {ct} recall I mentioned vectors ? I also mentioned Newtons laws of inertia. key formula being applied [latex] f=ma[/latex] or any equivalent formula such as the coupling strength of a field. They are in essence the same except the fields involved. It takes more energy to achieve the same distance covered, the mass term is higher so 1 Newton of force will move the object less in a higher potential. This applies to all processes in the same potential conditions, it affects the rate at which all particles in the immediate locale interact. (hence the twin aging, different clock rates, rates of decay etc.) You should be able to formulate how inertial mass relates to the mass in terms of its binding energy to the time interval used in coordinate form. It should also help understand why the Lorentz transforms apply to both the time axis and the x axis where the object is described as moving away from or towards the observer. see here for the transforms. Each transform describes the interval length (defined as a vector ) change between reference frames due to the mass terms influence. recall as an object gains inertia it gains inertia mass... Now spacetime curvature as promised. Think of this as a coordinate map with axis [latex] ct,x,y,z[/latex] when you have no curvature terms then Pythagous theory applies in the triangle identities. Angles on triangles will add up to 180 degrees. Our regular everyday vector commutation rules apply. We also have no appreciable time dilation so our coordinate axis are all identical and 90 degrees from one another. When you get time dilation affects however this no longer applies, the angles no longer add up to 180 degrees, this is due to the length contraction and time interval contraction. It is now skewed to the original symmetry (skew symmetric}. the amount of skew depends on those transforms in that link above. Now spacetime under GR describes the freefall condition (constant inertia). This freefall condition has a further detail that of parallel transport. Instead of having 1 object drop , drop two or more. In the case of the Earth the centre of mass is at the centre of the Earth (roughly). So these dropped objects no longer fall parallel to each other they converge upon one another as they approach the centre of mass. Now depending on arbitrary choice we can say this is positive or negative curvature but that's really an arbitrary choice. The position the two dropped objects will diverge in the opposite case. granted the above is largely a simplification however all the essential principles are there. The last example is an example of tidal force under GR. One of the things to remember is that under GR objects follow the shortest spacetime path, that path is mathematically defined from the above under a freefall symmetry basis. The curvature terms apply to the particle path or its worldline. Usually denoted by the separation distance [latex] ds^2[/latex] this will contain the details on how those coordinate axis transform in regard to one another in describing the freefall world line of a particle. The convergence and divergence of said curvature will affect the parallel transport of multiple particles. An everyday analogy of the above, think of time dilation in much the same way as signal propagation delay in electronic circuits. Where the signal can be delayed as it passes by an EM field in the right alignment. The physics behind the two is very similar. the constant c isn't simply the speed of light it is also the restriction of all information exchanges between any two points or particles.
    1 point
  16. So you are going to ignore that from your own list there is a substantial element alignment with what is considered the progressive (i.e. non-moderate) program? Also the fact that both parties offer policies that are on the conservative side of things as they judge their constituency more conservative then they are. Also the fact that in the article you linked one of the issue is simply that moderate politicians may just not be sufficiently aligned with what voters ultimately want? To explain the issue it is probably worthwhile to point out that labels such as moderate are ultimately not helpful. The reason is that there is a significant gap in self-identification and desired policies. For example, while many minority communities share strong overlap in terms of social conservative ideologies, which could include aspects like the role of women, abortion, role of religion, LGBT issues etc. they tend to vote Democratic as a whole. The reason here is that for many the GOP stance toward immigrants and minorities can be seen as soft (or even hard) threat to them which is a disincentive for them to vote GOP. Likewise an astonishingly high number of especially low- middle income Republican voters are strongly in favour of medicare and/or universal health coverage. Yet clearly the GOP was hard on against it. They likely have to pivot now, though, as it seemingly only slowly dawns them that they were leaving their voters behind. While there is clearly a party bias, the US population as a whole is astonishingly comfortable with progressive stances (and again, as reflected with your previous list) and as such, the political continuum as represented by both parties is not representative for the spectrum found in voters. This does not mean that there is a space for moderates. As mentioned before, the moderate would have to pick and choose not from the middle spectrum, but it would be squarely in the moderate to left part of the Democratic party. The other option would try to obtain votes from the hardcore left or right base (no Immgration of Muslims, but with free healthcare for all!), which is likely not going to work for a large number of reasons.
    1 point
  17. You’re a bit of a bomb thrower. I treat you with respect. You, however, toss labels like leftist at me, seem compelled to insert division and wedges into every post you make, and accuse me of Orwellian double speak all while claiming some arbitrary high ground of moderation you don’t exemplify yourself. I’m not interested in helping you continue to set fires.
    1 point
  18. ! Moderator Note As this seems to be a discussion of what it means to"exist" or be "real", I have moved this to Philosophy. However, as argo is now just repeating the same claims as before with no further explanation of justification, it is closed. Do NOT open another thread on this subject.
    0 points
  19. Reverse of "natural selection" is not "supernatural selection" but "artificial selection" (aka "selective breeding"). Artificial selection is selection made by human on farm animals.. https://en.wikipedia.org/wiki/Selective_breeding
    0 points
  20. It differentiates from artificial selection (breeding), so how is that redundant? You have rejected it but apparently the scientific community has not.
    0 points
  21. Well I think some qualifier is useful, if not essential in the phrase "Natural Selection". I fear you have fallen into the old trap of assuming binary choices (either ...or...) If it is not 'this' it must be 'that'. What about "self selection" for instance ? As I understand the theory, "Natural" refers to selection during the to the normal everyday environment and the selection it produces. It does not refer to unusual or special environments (accidents) that may only occur once or to specially arranged environments such as human crop selection etc. In any event, in my view, it is worthwhile to distinguish between different filters.
    0 points
  22. @studiot No, I don't think I have fallen into any old trap of "assuming binary choices (either ...or...), if it is not 'this' it must be 'that'". If you use some qualifier, then there must be something else, that is outside of its scope, and is not pointless at the same time. I gave two options that I could think of, which both don't have much sense to me, so I concluded that the qualifier is redundant. And "self selection" never occurred to me, as the whole point is that environment selects you, if self selection would be the case, everyone would choose to survive. Right? I mean, it is not like everyone doesn't try to impact the environment in order to make it let them survive, but eventually, the environment is the one that selects you. Unless you don't talk about suicide here? @Sensei First of all, you are responding as if I didn't mention artificial selection at all, and then if you think that for some reason this should be separated from "natural selection", then you don't believe homo sapiens is a part of nature, ie as natural agent as, well, everything else that exists in the nature. The only answer given here, that I would tentatively and partially accept, was by John Cuthber, when he said that for historical reasons, one should continue to use that syntagm, as in the start it was used to denote the difference from "unnatural", or "supernatural" causes, ie not that part about Green party activists. And what about philosophy community? Apparently you can speak in its name too.
    -1 points
  23. 1) Your chain of reasoning was limited to a binary choice. Why? There are multiple postulable origins and multiple postulable processes of selection. 2) Why would I refer to the supernatural, since JC had already done so and I don't agree with him, especially on a Science site? 3) We have only recently gained the means of modification by genetic manipulation but, as others have also pointed out, selective breeding has been practised for a long time. Further consider the taboos "Thou shalt not marry thy sister/mother etc" Do herds or packs of wild animals obey this maxim? 4) Selection is also about 'deselection' ; survival of the fittest implies perishing of the weakest. 5) You posted a general statement about style in English to which the answer is no, even if the qualifier is actually redundant, which it is not in your example. 6) On The Origin of Species is reckoned to be one of the most readable, if not the most readable, scientific treatises of all time. I understand this was by Darwin's design. Have you read it? Chapter 1 is all about selection under domestication Chapter 2 is all about selection under Nature (The environment) Chapter 4 is all about natural Selection and its comparison with So can you tell me where Darwin discusses the supernatural? It is always useful to avoid the trap of misquoting this wonderful document, either in its Title (as is often done) or in its body text.
    -1 points
  24. -1 points
  25. So, people are part of nature, and they have goals, but nature has no goals. Monkeys are part of nature, and they have goals, but nature has no goals. Dogs are part of nature, and they have goals, ... you can continue that line of reasoning to understand just how sensible is that what you are saying. "Normal everyday environment" for domesticated species means that people make their selection, which by this definition would be "Natural" for them, but I bet that you consider that "artificial selection". So yeah, "it should be clear and possibly unambiguous what is meant", but it is not. No, I did not. I posted a general statement about style in science. That syntagm is redundant if you say it in Latin, too. This really has nothing to do with English, or any other language. So, you dropped by to express your low opinion about philosophy community and their relevance, here, in General Philosophy forum? I can't say that I find that particularly interesting.
    -1 points
  26. Of course that I didn't. I have better things to do in my life, like, for example, discussing it, commenting on it, sharing with you my opinion about it, things like that. And writing my own most readable scientific treatises of all time. Have you read them? They are already reckoned as such by some people, notably my girlfriend...and her sister.
    -2 points
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