studiot

I'm sorry I don't understand this comment. Heat is not necessarily a bad thing. The capacity of an electric vehicle battery decreases markedly with lowering of temperature, (or raising it above optimum which is in the 20oC to 23oC range) The car manufacturer will specify the capacity at this temperature. At 5oC the capacity will be 25% - 30 % lower and it can be as little as 50% lower in freezing conditions. Also the capacity depends upon the equipment used to charge the battery. The Kia Nero has a 64kW-hr rated battery. But it needs a 3 phase supply to achieve this capacity. Ordinary UK mains can only reach 80% of this value ie 51 kW-hrs, I recently charged a Kia from completely flat to this level - It took 28 hours charging at 10 amps on the UK 240 volt mains. This equates to 67 kW-hrs. So the charging efficiency was 51/67 x 100 = 76% Other types of lithium-ion (there are several types) batteries have different characteristics.

OK so the Telegraph has done its job as a respectable paper pretty well. These figures concur with other sources I have. In particular my Cambridge Handbook of Earth Science Data (mine is the first ed 2009), which gives all sorts of tables of useful data on - well Earth Science In the chapter on the atmousphere it lists much more comprehensive composition data, including non gaseous components such as dust and volcanic input. It also references other reputable sources such as NOAA, The UK Met Ofice, standard texbooks on Geochemistry, Chemistry and Physics. Amongst many other data tables, it offers a table of of the energy fluxes between the Earth and its atmousphere that may be a useful addition to your Telegraph data. Just a small point about you Telegraph data. The difficulty with the halocarbons is not the greenhouse effect, but their chemical action high in the atmousphere to deplete the ozone layer which proctects us from harmful high energy solar radiation.

No I don't mean particles of any description or size by a source or a sink. Sources and sinks are an inseparable part of Field Theory in general and Maxwell's field theory in particular. If you are developing a Field theory, you should understand this and provide for them. You magnetic pole example is such a source, the other pole is then a sink. Again you missed my point. Maxwell's equations lead directly to a (continuous) wave theory, which is incompatible with photons. See in particular 8.7 here

Yes chenbier is correct but perhaps you would like a bit more since your battery 'efficiency' is not the same as mechanical or thermodynamic 'efficiency'. Traditionally efficiency is defined as [math]{\rm{efficiency = }}\frac{{{\rm{output}}\;{\rm{energy}}}}{{{\rm{input}}\;{\rm{energy}}}}{\rm{ \times 100}}[/math] You have an input and a theoretically empty battery. This battery has a 'capacity' which is the quantity of electricity required to fully charge it or charge it to 100%. But here your 'output' is the actual amount of energy you need to put into the battery to bring it to 100% charge ie its capacity. Your 'input' is the amount of energy, an energy meter would read as input to your combined battery and charger. Some of this input energy is lost in the charger itself as heat and some is lost in the battery as heat. Both of these losses count as inefficiencies. So say the capacity of your battery is 1000mA/hrs, your energy meter would read 1500mA/hrs. so the efficiency is 1000/1500 x 100 = 67% as chenbier says. You must have noticed that chargers and batteries get warm during charging ?

What a short memory you have. You were told, right at the beginning to post the main material here, not as a link. But here you go again.

Please separate out your various points so that others can identify what particular piece they are responding, without having to point to the whole lot ! I only wish to comment on the last line of your post image and the title of the thread. I don't regard addition and subtraction as 'Fundamental Mathematical Operations'. Most certainly not in a Philosophy forum where the history of Mathematics can be taken into account in a thread entitled "Birth of Mathematics from Logics" Incidentally, in case you first language is not English, these last two nouns are singular collective nouns without an 's' on their ends.

I did not take much notice of your earlier threads as you started with too much and too complicated material. So I welcome this fresh start +1 for a nice compact introduction to your question. In Mathematics you can define (choose) all sorts of variables. Many of these are not (very) useful. Science uses maths a great deal and gives the name 'time' to a particular variable it finds exceedingly useful. Useful in formulae, expressions and equations. Measurement of time is a separate subject and I would recommend a 2022 book by New York Physicist, Chad Orzel "A Brief History of Timekeeping" Chad opens the book by discussing the question "what is time ?" and may be to your liking - It contains much fascinating material. By all means carry on this discussion here if you like the start we have now made.

+1

Thank you all replying. To me 'the obvious engineering solution' to the fact that there is too much water (over time) in one area and too little in another (again over time) is to move some water about from the excess to the deficit. I have put this in climate change because it is predicted that this imbalance will grow as climate change bites more and more. I was not my intention to limit examples and discussions to the US experience. It's just that their recent news renewed my long held conviction that worn out 'politix' has made / is making matters worse rather than better. There is not much known about the Harappan civilisation and there are several overblown stories or myths. But we do know this bronze age culture was able to control the Indus river basin and the monsson by exactly the engineering means I have described "Collection storage and distribution" Meanwhile in the UK we are also suffering this water imbalance, though to a lesser extent than the US. But late 20th century politix has removed our golden opportunity to do something about it, by breaking up a water industry that was brought together into a coherent whole during the early 20th century, and selling it off in disparate chunks to foreigners with no interest in our plight.

OK you are serious. We are all very glad to learn this. Welcome, my apologies for doubting, but unfortunately there are too many nasty people about and this site encounters its fair share of them. Looking quickly at the development of your discussion, a couple of things stand out. 1) I see no sinks or sources in your treatment. These are very important in the real world. Are you assuming that these three fields were and are always present everywhere and everywhen ? 2) I see no discussion of the clash between the continuous Maxwell field theory (which is compatible with both special and general relativity) and the Plank relationship E =hv which defines Quantum theory. I look forward to your answers

No you are not wrong Your 'thinking' is so far out of line with any section of this forum that the old scientific statement You are not even wrong applies.

Yes perhaps it was an oversimplified picture. +1

No collapse is really a poor term. What happens is that the interaction selects a particular solution from all the possible ones in the superposition. This is just like you choosing which square root you want when you select -2 (or +2) and use it as the square root of 4. MigL also make a good point +1 That there with a complicated macro system there may be (probably will be) many small self interactions between parts of the 'collapsing' system. Rather as some parts of a large structure fail before others when it collapses structurally. I don't know if there is any quantum situation similar to the transition from elastic failure to plastic failure which works like this. That would be an intersting speculation to pursue.

The Game of Thrones finale was an interesting study of this question.

I see someone has been foolhardy enough to download an dot_htm document, which could easily contain harmful code. As @exchemist +1 says you you should post at least a sufficient summary here for discussion to take place. additional documents and links to references are for links to supporting material to any claims you make here.

It is not necessary to use tensors to understand geodesics.

Observation means any interaction whatsoever with the environment/surroundings. So just how difficult is it for a macro object not to interact with its surroundings ?

As I read about droughts in California and Texas, but floods in Kentucky I wonder if the obvious engineering commonsense reaction will pertain. We need more water collection, storage and distribution facilities compared to the past. Will politix ever permit the obvious engineering solution ?

If you think mothy looks bad, you should see the other guy. I picked him up whilst walking along a lane in very rural Herefordshire a few days ago. Had a great holiday tramping the Malverns and visiting the oldest rocks in England. We have had noticeably fewer insects here in Somerset these last few years, but they still have plenty in Herefordshire.

Thank you I think you have found it. +1 The male Oak Eggar on Wiki looks very much like it, including the two small wingspots

I have worked on oil rigs and barges that do this. Many small pleasure vessels also still do this.

Not really. mistermack is hinting at what developed in classical mechanics and and is now also used in quantum mechancis and fractal mechanics (in computing) This is the system of Generalised Coordinates, of Dimension n. Definition If the configuration of a system S is determined by the values of a set of independent variables q1...qn then {q1.....qn} is said to be a set of generalised coordinates for S, of dimension n. The qn are often momenta in classical mechanics. The set, S, is called the phase space. https://en.wikipedia.org/wiki/Generalized_coordinates Generalised dimensions are more modern and there are many modern texts on the subject https://www.google.co.uk/search?hl=en-GB&gbv=2&q=generalised+dimensions&oq=generalised+dimensions&aqs=heirloom-srp..0l5

Never seen one like this before. Can anyone idnetify it please ? It is dark brown with yellow bands on the wing edges and tips.

For Ronnies fans. Notice seen recently in a hardware shop in Ledbury.

There is an existing framework within Theoretical Physics for this. This is because the concept of 'dimension' appears in several different forms, each with its own characteristics. You are proposing a different mix of traditional continuous dimensions as used in traditional geometry to descibe shapes. Such mixes have been studied, and when Relativity came along, Eddington discussed in some detail the possibility of employing 1,2,3,4, ... n spatial dimensions and 1,2,3, ...m temporal dimensions early in his treatise "The Mathematical Theory of Relativity". Minkowski added the possibility of 'imaginary' dimensions by using complex numbers instead of real numbers. The possibility that the Universe is not continuous in the traditional sense was also studied and that fractional dimensions (fractal) may be required This was demonstrated most vividly by Mandelbrot with his question "how long is the coastline" In a different line of attack, it was realised that there is a tie up between the number of variables needed to completely specify the condition of a system and the concept of dimensions, since these variables can be plotted on a multidimensional 'graph'. So in Thermodynamics we have state variables ( +1 to @OldChemE ), in Mechanics we have phase variables and so on. The physics of the particular system gives us a new relationship. That of constraints and degrees of freedom. The Physics of the system gives us a set of relationships (usually equations) between the variables and all these quantities are called 'dimensions' in some system of analysis or another. The new thing is that we can use these relationships to trade off between the total number of degrees of freedom, variables and constraints. So in thermodynamics we need one less state dimension than the 3 - P, V, T as knowing 2 will always allow calculation of the third. This brief survey hopefully shows that there is much more to this question than at first meets the eye. Good topic, +1