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studiot

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Everything posted by studiot

  1. cuts off the electricity of the brain and then turns it on? That is an exaggeration, if you read the article carefully. Our whole bodies, run on electricity. And the squirrels have an unusually low residual state in hibernation. Electricity is not turned on and off like a light switch, it is an integral part of body processes.
  2. I have another comment that I doubt you will like. I have a soft spot for analogue systems. Discussion so far, as so often these days, has concentrated on discrete systems. Nature has no such requirements and uses both analogue and discrete systems as she feels appropriate. The large majority of Man's early constructs have been inherently analagoue. It is only comparatively recently that we have tried to fit everything into the discrete mould, often developed from analogue beginnings. Both analogue and discrete approaches have pros and cons, but discrete ones have an inherent limitation not suffered, in principle, by analogue ones. So it would not suprise me if one day artifical consciousness was generated from an analogue system.
  3. The equipartition theorem no less. +1
  4. Well microwave radiation is certainly a large, wide ranging subject in its own right. So I was going to ask you "In what context are you interested in microwave emitters and their construction ?". But clearly microwave emission is happening all the time around us or there would be no microwaves! If the EmDrive works at all, which I doubt, it is all in the tranmission aspect (ie waveguides). So pony up and focus your question please. I take it you are not interested in the biological aspects I mentioned. Note the heating effect of microwaves depends on indirect heating of water or sugar molecules which in turn heat the whole material in you microwave, but as Seth noted these are not the sort of microwaves you generate from pea sized emitters. Here are some real figures and a calculator. https://www.everythingrf.com/rf-calculators/cavity-resonance-frequencies
  5. I was answering your question how EM (no particular frequency) radiation could impart translational energy to molecules. Changing the state from solid to liquid or liquid to gas seems to me to be adding KE to the molecules by the bucketful, since they are then rushing about in a way they did not before the irradiation. Perhaps I misunderstood you.
  6. Laser vapourisation ? https://www.mayoclinic.org/tests-procedures/prostate-laser-surgery/about/pac-20384874 Laser welding and other uses of lasers as heat sources to melt materials ?
  7. Heaven help us if some fools combines this self awareness with that shape shifting robot that melts itself to get outof jail. https://www.bbc.com/news/av/world-us-canada-64668021 Oh sorry they already did that in Holywood - Terminator II.
  8. The idea of unchemists doing unwork fantastic. Reminds me of that great letter about setaside that was doing the rounds about 10 years ago.
  9. Yes, why not ? The smallest microwave wavelenght is 1mm so a quarter wave antenna is only 0.25mm. Many insects have antenna that are in the 0.25 to 5mm length range and some are known to respond strongly to microwave radiation. Equally artificial antenna of this size can easily be constructed.
  10. I wish I could give plus one for each line of this. Just so funny.
  11. OK Both, I believe. Misner, Thorne and Wheeler include description and references in their chapter on gravity waves. But I would say my most important point concerned was the sheer size of objects involved, seeing as you seem to be interested in what possibilities there are for manipulating gravity. You also need to be careful to distinguish between working in space and time separately v spacetime. A wave equation is an eqaution connecting space and time. The ordinary (linear) wave eqaution allows separation of these two variables, by virtues of the linearity. Gravity waves occur in spacetime, but as I said before linear ( ie linearised versions), so the model is essentially non linear. This arises because the solutions to the wave equation, being a partial differential equation, contain arbitrary functions, and it is usual to choose the simplest. But a gravity wave equation will have additional complicated (even complex) relativistic conditions that must also be met. Considering your antenna: Antennas are passive devices (and only thre dimensional at that), which means that they do not generate the required wave, that has to be done by somethng else, as does any modulating signal. So you would still need all the paraphanalia already under discussion. Also since the waves are actually 4D, what do the 'lobes' of such an antenna look like in 4D ? Directional antennas are not impossible in theory because there is already a phenomenon called gravitational lensing (which again involves the big guns) under observation.
  12. Yes, you are right about a no-operation, which also applies to Turing mschines. The point about a halt instruction is that as far as I know it is not Turing, but required in some older programming languages. I always used to smile at having to write Stop End Finish I'm pretty sure that was some early Fortran, not Cobol. Your point about interrupts is also interesting. +1
  13. Engineers still use the term Heat Content (AKA enthalpy). Are you going to answer my question ?
  14. Since you chose not to respond to my mushy comments, is there any reason I should add to them ?
  15. I think learned should include 'worked out for yourself.' I think most folks don't decide for themselves when they first hear about religion, they are indoctorinated. I don't think many are indoctorinated as aethists. I thin aethists are much more likely to 'work it out for themselves' Perhaps Genady (no criticism) is a self confessed work it out for themselves person.
  16. Sounds like the story of the bigendians v the littleendians to me.
  17. Yes, stress can be thought of very simply as force per unit area, but there is much more to it than this because that force can be applied in one of two mutually perpendicular directions viz perpendicular to the area under consideration or parallel to it. If the force is applied at some other angle then it can be resolved into components parallel and perpendicular to the area. Stress is an internal force to some body. External forces are useually called loads. All real world bodies respond to stress by exhibiting strain, although it is often very small so we often work in units of microstrain. When the strain is to small to worry about, we call the body a rigid body. Strain is sometimes the result of that stress, but no always. Bodies also exhibit strain when their temperature increases and if they are free to expnad we observe stress free strain. Finally strain can also be resolved into components, like stress. Does this help ?
  18. studiot replied to toucana's topic in Politics
    An amusing history of spy balloons from the French Revolution on https://www.bbc.co.uk/news/av/world-us-canada-64639407
  19. It's not a good idea for several reasons. The original caloric theory of heat was a two substance theory, heat and cold. Of course today know that neither heat nor cold are actual substances. It was also realised that two substance theories cannot explain all phenomena, for example what happens when a pure substance melts or solidifies. What flows which way then ? Another difficulty is that cold is incompatible with the idea of internal energy, since energy is a positive definite quantity, what sort of quantity is cold that can reduce it ?
  20. I'm not sure about extensive calculations on the wind regime since we are really interested in the effect of the wind on the wall, rather than the other waya round. So let us start from two proportionalities, since proportion is the simplest variation mathematically. Assuming the force of applied by the wind is proportional to the square of the speed, V, with constant, b F = bV2 And assuming that the wind speed is proportional to the height above the ground. h V=ah Substituting for F yields and combining constants. F = ba2h2 = ch2 This leads to the total horizontal shear force due to the wind at the base being [math]Shear = \int_0^h {Fdh = } c\int_0^h {{h^2}dh = } c\left[ {\frac{{{h^3}}}{3}} \right]_0^h = c\frac{{{h^3}}}{3} = \frac{{c{h^3}}}{3}[/math] That is the shear force is proportional to the cube of the windspeed But the reaql kicker comes with the moment induced at the base of the wall, which is seen to be proportional to the fourth power of the height. [math]Moment = \int_0^h {hFdh = } c\int_0^h {h{h^2}dh = } c\left[ {\frac{{{h^4}}}{4}} \right]_0^h = \frac{{c{h^4}}}{4}[/math]
  21. Probably best to discuss this in terms of turing machines. Here is a simulator. https://morphett.info/turing/turing.html
  22. Thank you for updating me, +1 I am going to show my age by saying I wasn't aware of the change.
  23. Well they would be wrong about this, but it would certainly be different from the gravity we experience. Several comments about dimensiosn. Firstly obviously a space on n dimensions cannot support an object of higher ( >n) dimensions. But there is a huge amount of established theory for objects of lesser dimension than n embedded in n (or more) dimensions. So for example in one dimension there are only lines and in two dimensions there are only surfaces. But there are also lines in two dimensions And there are lines and surfaces in three dimensions and so on. Another thing about dimensions are the properties and actions that are possible depend upon the number of dimensions. Rotations are impossible in one dimension. They are incomplete but possible in two dimensions. By incomplete I mean that you need a third dimension to fully describe them. Rotations are complete in three dimensions. By this I mean that you do not need another dimension to describe them every rotational axis is available in three dimensions. You do not need a fourth dimension for rotations. In fact rotations in the fourth dimension come in pairs. Similarly comments apply to curves since they are related to rotations. No curves are possible in one dimension, One curvature is available in two dimensions Two curvatures are available in three dimensions. I do not know of any truly one dimensional objects (except abstract ones) in two or more simensions but a shadow can be a truly two dimensional object in 3 dimensions, although the 2D surface may be a very complicated shape. They a
  24. I really don't know the answer to this but I was thinking that you need to distinguish between a 'do nothing' instruction and a halt instruction which is not the same thing. I would interpret a do nothing instruction as equivalent to the zero function in your terms, which surely would make it the same as Ghideon's wait instruction.

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