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Showing content with the highest reputation on 09/13/18 in all areas

  1. 2 points
    You changed the object from 'concept of God' to 'God'. The concept in itself can explain the building of temples, churches, etc. Condition is that those who use the concept believe that something outside the 'God discourse' match with this concept. Certainly, 'God' exists is a concept (however, in different cultures, very different concepts), but that does not proof God's existence. As Phi for All already said, there is a concept of unicorns, but that doesn't mean they exist outside the discourse about them. And if you think that the this is not valid, because the 'God-concept' is very special, you are nearing the ontological proof of God's existence. Hmm. Interesting difference you make here between 'being real' and 'not existing'. May I propose some other distinction? Things exist physically, if they play a direct role in causal relationships, independent of how we we talk about them. Things exist conceptually, if they are useful to describe the world around us, which includes things that exists physically (example: laws of nature), but also human behaviour (examples: marriage, stories, free will). The point is that we can refer to observable entities, to show what we mean with these concepts. And I think 'unicorns' and 'God' do not belong even to the conceptually existing things, because we cannot refer to observable entities.
  2. 2 points
    Absolutely. Adding up thin shells to create the full sphere is actually a very common technique to access the volume, i.e. [math] V(r) = \int_0^r A(r) \, dr[/math] Well, picking up on the integration example: The average distance <r> of a particle from the center in a sphere of radius R is [math] <r> = \frac{1}{V(R)} \int_0^R \, r \cdot A(r) dr = \frac{1}{V(R)} \int_0^R \, r \cdot 4\pi r^2 dr = \frac{1}{\frac 43 \pi R^3} \left[ \pi r^4 \right]_0^R = \frac 34 R[/math] (modulo typos: Tex does not seem to work in preview mode ... EDIT: And apparently not in final mode. The result in the calculation above is <r> = 3/4 R). There is a general tendency that the higher the dimension, the more likely a random point in a sphere lies close to the surface. There is a famous statement in statistical physics that in a sphere with 10^23 dimension, effectively all points lie close to the surface. In all sensible definitions of volume and area I am aware of (at least in all finite-dimensional ones), volume has one more dimension of length than area. Hence, their quotient indeed has dimensions of length. I don't think the quotient itself has a direct meaning. But there are theorems like that a sphere is the shape that maximizes the V/A ratio for a fixed amount of V or A. I already commented on the dimensionality. But I still encourage you to just play around with other shapes: Cubes are the next simple thing, I believe.
  3. 1 point
    Popular explanatory diagrams often show huge amounts of curvature, whereas in reality even Jupiter sized planets cause very mild levels of curvature. The original experimental proof of the curvature at the surface of the Sun sought a deflection of 1.6 seconds of arc for grazing light. The masses required to create Swartzchild conditions are many times larger. Perhaps Marcus could comment on this or Mordred (if he comes back). This is really their baby.
  4. 1 point
    No you are mistaken, the air flows do not cancel each other they complement each other, the lessening of the hurricanes winds is caused by things like ocean temps and wind shear. https://image.slidesharecdn.com/cdb9bde1-df1c-4325-8810-fd99ac44d65e-151230203327/95/tropical-cyclones-presentation-19811988-4-638.jpg?cb=1451507711
  5. 1 point
    Fair comment. I apologise if I misunderstood and misrepresented what you said.
  6. 1 point
    Eloquently put. I can't really say I disagree with anything.
  7. 1 point
    Do you use the term Mother Nature? Many theists, atheists and agnostics use the term, knowing nature to be true. However, like hot or cold, nature is not a thing unto itself... it's a property of other things. The planet and the universe. Free will does not make water hot or cold and despite all of the available variables we can impose, it can only be in one state at any given time. Therefore neither can be wrong. Each have a time and a place for us at different times. It's when we put a face on it, or deny it's existence entirely, is were we go wrong. Hence my position as an agnostic. Jonah being swallowed by a whale is a bunch of crap, as is the great flood, but Ecclesiastes 3:1-8 is wise. There is good and evil in everything and that is where free will allows for us to find or lose ourselves as individuals. Most who grasp the concept of nature understand grandeur, beauty, retribution and destruction (to name a few). These are the identical things theists advocate when they speak of god. The difference being, nature does not play favorites, pass judgements nor listen to individual prayers. We understand that when we intervene with nature by actions, there are consequences. Nature does not show retribution for our thoughts, but sometimes for our actions, yet moreover for reasons we may never understand. This we know to be true, as well. An eight year old girl told me once "Big fish eat little fish and that's just the way it is" It's true, wisdom often comes from the mouths of babes. Thank goodness humans developed morals, because we'd otherwise be cannibals or ruthless cold blooded killers. When we apply these morals to nature, we understand there's no need to do certain things, even though we can. In that vain, there's liitle to be conquered or dominated. We accept that some things should just be and it has absolutely nothing to do with any of us, other than being a part of the big picture. I'm a follower of Ed Ricketts, as was John Steinbeck, Joseph Campbell and Salvadore Dali, to name a few. His philosophy was wrapped in the science of the ecology... the economy of nature and like Ecclesiastes, a time and purpose for everything, how necessary voids are filled, that things may be reborn and how species may co-exist.
  8. 1 point
    Hurricane winds blow in different directions at the top and ground level. Think of it as a two whirls, going in opposite directions changing directions in the eye as the surface winds spiral up into the stratosphere and back out over the lower cloud decks. It is an odd effect, I've seen it many times, the whole hurricane is strange compared to normal thunderstorms yesterday it was almost dead calm here, almost suffocating, today the wind was blowing five to 10 mph but always in one direction as the eye approaches the wind will pick up to and beyond hurricane force and continue from the same direction, then the eye will pass over and the air will be dead calm and often very sunny then suddenly the wind will start up directly to hurricane force but from the opposite direction. You have to be careful about going outside when the eye passes or you'll be caught be the full dorce of the storm before you can get back inside...
  9. 1 point
    As stated before, battery storage is already used in the energy system. Just not to systematically balance renewable power generation. The most common application is balancing the discrepancy between electric power forecasts used for the operation planning and actual power generation and load. I believe that the Tesla battery mentioned by pzkpwf falls in this category. On a smaller scale, batteries are often used within private/business premises to maximize the use of self-generated photovoltaic power or as backup power source in case of failures (link). The topic of storing renewable energies usually comes up in the context of electricity generation from wind power and solar photovoltaic power (PV). Often in contexts like "the weather dependency of wind and PV make it impossible to create a reliable electric power supply" or "we need to solve the storage problem before we can build renewable power systems". The short answer why batteries are not considered as the storage solution is that they are too expensive for really large amounts of renewable wind and PV generation: Battery capacity costs money Fully-renewable power systems need large storage capacities - in the order of a month of electric power supply It is more economical to create synthetic fuels to satisfy this backup storage demand For a more detailed explanation, keep on reading ... Detail Explanation I'll use Germany as an example, because I have data for it at hand. At least the European weather conditions (and almost certainly also the northern American weather conditions) are sufficiently similar, anyways. Also, I will focus on wind and PV generation as well as batteries and synthetic fuel generation as possible storage options. There are many other options for generation and storage, and some can be very relevant for specific areas (pump storage in Norway, hydro power generation in Iceland, concentrated solar power in northern Africa, ...), but wind, PV, battery and hydrolysis are somewhat universally-relevant options. Wind and PV power generation depend on the weather and vary significantly over time, whereas the power demand (=load) is relatively stable. This creates an imbalance between generation and load that must be match by additional demand (or exports), curtailing of the power generation or additional generation (or imports). The following image shows an example of an optimized renewable energy system with onshore wind, offshore wind and PV as power generation, gas power as additional generation option, hydrolysis and methanation (the creation of hydrogen and subsequently methane from water and carbon) as additional flexible demand, no import/export, and curtailing where needed (called "Lost Generation", here). As you can see, batteries do play a role in the balancing: They are systematically charged by the daily PV peaks and discharged in the evening. The reason they do not cover all of the balancing demands is ultimately a question of economic viability and the cost of battery capacity. The high-frequency daily charging/discharging makes very good use of the battery capacity since the annual energy throughput is roughly 365 times the installed capacity - up until you have so much capacity that you don't fill it up every day and get diminishing returns. There are, however, lower-frequency storage demands, i.e. longer times of effective surplus or deficit power. An example are the 3-5 days of low wind power generation around hour 5800 in the plot above. Even the annual generation of wind power changes by ~10% between years and may have to be stored for bad years. The events occur relatively rarely, but are associated with lots of energy. For a fully-renewable power generation, the total capacity required of the storage system is significant. For the example system used in the plot above, 45 TWh of electric energy (-equivalent) storage are needed. Assuming 300 €/kWh battery costs and 10 years battery lifetime that means 1350 * 10^9 €/a costs for the storage alone. But the total cost of the German electricity system today is only 100 * 10^9 €/a. For low-frequency, high-capacity storage needs, the creation of synthetic fuels via hydrolysis (for Hydrogen) and possibly further steps (for Methane or theoretically even fluid fuels) is more suitable. It is associated with high losses, but fuels are very efficient to store in large quantities of energy over long time. So instead of using batteries alone, a mix of storage options is used. Highly efficient but capacity-limited battery storage for high-frequency storage and low-efficiency high-capacity synthetic fuel storage for the low-frequency storage. In the example of the plot above, the battery capacity is 120 GWh (i.e. 0.3% of the total capacity demand), but has an annual throughput of 30 TWh, whereas the fuel storage is 45 TWh with an annual electric energy output of 55 TWh (for reference, the total annual demand is 450 TWh).
  10. 1 point
    If you take a narrow view-- as in which field of engineering designs which products, there could be an excess in some fields now and then. However, one of the value-added aspects of engineering is that you learn to approach problems and find solutions. It can demand considerable creativity. The engineers with creativity and the necessary education in the science and math needed to apply the creativity are very rarely without well-paying and fun work. Of course, Engineering is not the only field that benefits from creativity-- but its creativity coupled with knowledge of science and math that makes fields like engineering stay in demand.
  11. 1 point
    Interesting. Found this bit talking about it more directly. https://wjla.com/weather/weather-nerd-alert-here-s-something-we-found-interesting-today-10639
  12. 1 point
    It still sounds no different to me than saying unicorns are real because of the causal effects they've had on so many young girls growing up. If you use the most common definitions of god(s), as well as the scientific definition of evidence, this is nonsense.
  13. 1 point
    Kafei has been banned at his request. We thank him for cutting the red tape, since it would have been a few hours more before other mods could have weighed in and agreed to that action. Also for the lesson that claiming you haven't broken any rules means nothing when you don't actually know/understand what the rules are.
  14. 1 point
    That's interesting because I feel exactly the same way. I don't want to be famous. I have no idea why so many people do. I know that your idea is wrong, simply based on the fact that everyone regards Turing's proof as perfectly valid. Modern computer science is based on his ideas. However as I indicated earlier, I'm not a CS expert. I know Turing's concepts and results, but I am not schooled in the technical details as a CS major major would learn them. I can't exactly see why your argument is wrong and can see I'd probably learn something from taking a run at it. I'll see if I can work through your idea this week. I'm a little busy with other projects at the moment but I'll put it in the queue. TO @Olfaction, I wanted to explain why I have trouble with your exposition. You can see that @fiveworlds has stated an argument that is so specific, that it invites step-by-step understanding so as to refute it. It's wrong -- almost certainly, because it contradicts a well-known standard result -- but it's specific. I can follow it step by step ... because there are steps! And in working through @fiveworlds's presentation, I'll probably learn something or at least set myself a fun puzzle. Whereas your exposition is handwavy. You say, "apply the same argument" but you don't say how to do it. You say that things are intuitively or clearly true, without presenting proof. It doesn't motivate me to work hard to understand you. I hope you will take this as constructive criticism. I am sure you have the kernel of some interesting idea, but you haven't provided enough detail for me to understand what your idea is. I encourage you to try to express your idea more clearly and succinctly. > :nextState(boolean function) @fiveworlds, Are the halt() statements underneath that line supposed to be indented? Are they part of the function definition? Also is this a notation you made up? Or is it a standard notation for TMs that I could read about somewhere, and if so where? * ps another question. In HALT() you say to output "I'm halted." But you didn't produce an output. For a TM to be considered to have halted, it has to halt after a finite number of steps and output some number. Formally it's helpful to think of TMs as functions from the naturals to the naturals. It inputs a natural number and it has to output one. In fact you seem to be missing the very computation that you are required to make. Could that be a flaw? Not sure yet, just trying to understand your idea. * ps -- another comment. Your program produces no output! You run it and it either halts or ends up in the stuck state (halting at an invalid state is regarded as not halting, in TM lore). Your function does nothing!! You run it and after a while it halts and outputs "I've halted," but it never computes anything at all! I think this is an aspect of your idea that needs to be fixed. You have to output a number. I mean you could just add the line "outout 47" to your HALT() function, but that's just the TM that computes the constant function 47. It certainly doesn't solve the halting problem. Help me out here, what is this notation supposed to do? * ps another question (the forum software will merge my replies anyway so I'll just stick them here): > :halt(input == toBin(":halt(true and not false)")) what are those inputs to the inner :halt? And if this suppose to be recursive, your :halt calls itself? With what arguments? What are true and false here? I think I'll stop asking any more questions till you clarify this notation.