studiot

+1 Thanks both I note quite a few posts about oil pricing strategies. One strategy that has been prevalent in the UK is that since oil companies control the end user supply, even if they no longer control the production or bulk supply, is for them to price domestic fuel oil competitively (ie slightly lower) than the equivalent gas or electric alternative. This has ensured continuity of market for decades. They could have 'price gouged' those who are not connected to the gas or electricity grids.

The works of Darwin that I have read offer in substantial part a report on actual experiments and observations, not any 'theory' at all. In all the cases I can recall he works from observation to theory, not the other way round. I have not heard of Neo Darwinism and in any case you shoulld make your own arguments, rather than draw upon the works of others. Quotations should be employed to illustrate what you have already presented in sound (thank you Eise) argument.

Well you certainly don't understand STR if you think it is in any way connected to charge, or for that matter temperature. If you are studying the motion (STR is all about motion) of a charge particle or particles then you have to consider charge as well as STR. FYI Dirac was the first to do this successfully. Please also reproduce your definition of 'causality' in relation to STR. In mine the may or may not be a causal effect , STR simply defines the conditions under which such an effect can be observed or exist.

That wasn't an objection that was an attempt to supply additional information. If there is more than one premise either the premises are totally independent from each other or they are not. This has a bearing on the deductive process. All I was offering was a link to some well presented tables tabulating possibilities.

No you have neither explained nor supported your answer you simply made statements about something called STR What is STR or SRT the one time you used that version please ? I think I have managed to decypher IFR please confirm you mean inertial frame of reference ? If that is the case you clearly misunderstand what a frame of reference is, let alone an inertial one. Frames of reference are abstract constructs to aid calculation. Real world objects do not enter or leave frames of reference, they do what they do regardless of such abstract overlays.

Perhaps this See commentary https://www.quora.com/Does-Lawrence-Krauss-s-book-A-Universe-From-Nothing-justify-its-title-Is-what-he-calls-nothing-really-such-What-is-wrong-with-defining-nothing-as-synonymous-with-nonexistence-to-ask-Why-is-there-existence-itself

I really don't understand this thread,though I too have read every word. For instance I have a 'feeling' of what price gouging as, as probably does everybody else. But I really think matters are far more complicated than is being portrayed here. Surely Zapatos example on the previous page is not a result of disaster or market disruption ? Here is another example, that illustrates the complications that may be hiding in the background. If I go to a fair, an exhibition or other temporary event I expect to find that ice cream, burger and hot dog prices etc seriously inflated, sometimes by integer factors rather than %. Is that price gouging on behalf of the suppliers ? Well the hidden factor is to consider a typical ice cream vendor van who may have taken a pitch at the event. His costs will be increased substantially by the organisers' charges for the pitch as compared to setting up on a layby on a summer afternoon or trawling a housing estate. So who then is price gouging or the organiser ? Or perhaps the premises owners ? Or perhaps the financial institutions wanting a return on their investment ?

Thank you for this link. Quite a good presentation. I do note however, that the examples given are examples of what I was talking about, namely fallacies that arise from combinations of premises. swansont has already pointed out that he specified a single premise only.

Pressure is not the same as height. Pressure difference can result from height difference. It even says pressure in your article.

I too am confused by the OP. Photons have zero charge Muons have -1 charge. Charge is not affected by relativity transformations or causality.

I casually threw in system to see what resposne it brought. It is really good to see your response because it means we can make real progress. The concept of analysing a system is very cunning indeed and also very useful. Basically we mentally divide the universe into two parts. The system and the rest of the universe (also called the surroundings.). We mentally (or on paper) draw a dashed line around the system or a dashed surface in 3D to represent the boundary between the system and its surroundings. There are several benefits from doing this. Note I have gone into 'surroundings' mode. We may usually discount most of the rest of the universe as irrelevant or too far away to have any effect and only consider the immediate surroundings. Then we only consider variables which pass across the system boundary In mechanics the system is usually called free body diagram and the variables that act at the boundary are forces. In thermodynamics (the science of energy) the system is usually called the system and the main variable is energy. It is often easier to calculate the variables on one side of the boundary or the other and various conservation laws aid us by making the results of those calculations the same on either side of the boundary - So , of course, we look for the easiest one. Furthermore there are many other variables that we can calculate values within (or without) the boundary armed with only the knowledge of those variables on the boundary. This applies to various flux laws the most famous is known as Gauss' theorem (he was responsible for many theorems) So back to energy Another excellent reply, even if your original got lost, don't worry we have enough to be going on with. At one time energy was thought to be a sort of magic (invisible) fluid that could be added to or subtracted from bodies. A real but insubstantial substance. It took about a hundred years of work at the beginning of modern science to dispel this age old notion. For one thing energy is relative. Kinetic energy depends upon a body's velocity and that velocity must be relative to something else. Here we see immediately the system/surroundings concept in play. Energy is a measure of the effect the system can have on its surroundings or the surroundings can have on the body. So back to the Principle of least energy. A system can only reduce its energy by passing some on to its surroundings htat is by interacting with its surroundings across the mutial boundary eg by collsion, configuration or some other means. This idea applies right the way through the scales of systems. Elementary particles (photons, quarks, electrons and so on) all act this way Atomic nuclei Atoms Molecules Aggregates of molecules Planets Stars Galaxies. Please note there are also other effects in action so the situation is very complicated.

I can't imagine a worse predictor of the speed of tidal streams than this. What equation would relate stream speed to difference in height above either msl or minsl ?

Not to my knowledge. What would be the point ? When you say isoelevation, elevation above what ? Land elevation has a meaning as all elevations on Earth are related to some simple and recognisable datum that does not change appreciably with time.

I'm sorry I didn't explain myself very well but I was just packing up for bed when you originally posted so I was rushed. OK so iso means 'the same' The same what ? And also the same under what circumstances. First the simplest case. The same at two or more different places at the same time. Here is a map of part of North Eastern New Mexico showing typical looped or circular contours depicting elevations ie hills and mountains. These hills haven't been going anywhere for tens of millions of years so time is not a factor of interest. The pattern remains the same for very long periods of time. So we are just interested in place. Next consider weather maps and isobars. These change over time but recognisable structures move across the map so we are now interested in both time and place. Once again we have recognisable structures in the isobars but this time they do not stay put but move across the map. Now look at this tidal cycle for Narransett Bay As can be seen the shape of the figures varies over the tidal cycle from springes to neaps. This means that not only do the maximum and minimum tidal heights (and all others inbetween) vary from one day to the next but also the shape of the curve varies as we progress through the cycle. Added to this other places on the map have the matching points in their cycles at different times. Between these two variations they introduce a phase difference over both time and space. This phase difference is what I was referring to, rather obliquely, when I mentioned vectors. The point is that you cannot pick either two places or two times to directly compare. To summarise Contours compare values at two places at the same time. Isobars compare values at two places at the same time but a tracking series compares two times at the same place. Does this help

In my experience most problems arise when combinations of statements are made, the results depend upon the connective employed. Here is a good set of truth tables for first order logic about this. A disjunction of a false statement (premise) with a true statement has a truth value of true. https://docs.oracle.com/html/E79061_01/Content/Reference/Truth_tables.htm

Well I'm glad if you find something of interest in my 10 points. I hope you will keep them in mind when you hear what Imself and others have to say. I am , however, sorry that you chose not to answer my one simple question at the end since I wanted to talk about energy in my lightning tour. Please remember that whatever you tell me about your knowledge of energy (or anything else ) is very very useful helping me to work out how to put things. So the principle I want to talk about is the Principle of Least Energy. Very simply it says that any system however big or small tries to configure itself in a condition of 'least or lowest energy'. The implications of this statement are mind bogglingly enourmous. It is perhaps the most fundament of all principles because it addresses the system, and system behaviour itself. Many other principles (for instance the principle of relativity) is about how we view/consider the system, not the system itself. So let us work through what it means, from to the smallest to the largest. I am starting with the smallest because it introduces gravity and a short discussion about the 'four fundamental forces', three of which become significant when things get larger. Well the smallest system is completely empty space. yes? Well actually no. It can be shown that the energy state of completely empty space is greater than the energy state if that space if filled with one of Mordred's Fields. (Remember Mordred was a black magician https://en.wikipedia.org/wiki/Mordred ) To be continued

Not as such no. Temperature and pressure are scalars like elevation and isomaps are countour maps. Tides have two charateristics that make them unsuitable for such maps. 1) Tides are vectorial. They have a height, a direction and a velocity, all of which vary with. 2) Tides vary with time. Incidentally marine maps are called charts. Tidal maps can be obtained in tidal atlases. Here is the front and one extract from my local area The complete set comprises 13 charts with arrows and stream rates (in knots) from different times of the tidal cycle.

+1 Chorus from the gallery Hear ! Hear !

entanglement diode. What will they think of next ? I have never heard of them so thank you for the reference. One small point however, eleds apparantly emit entangled photons not electrons. https://www.nature.com/articles/nature09078

Zigbees https://en.wikipedia.org/wiki/Zigbee This thread has certainly expanded my knowledge of the different types of fire alarm available. Thank you all OP please note you will get a better response if you use the above phrase, from time to time. On this morning radio they were talking about remote controls, and one participant now uses their smartphone to control their television since they have lost the original remote that came with the TV. This can also be the case with a fire (or other) alarm. I am also reminded that a couple of years ago an electrician gave me a mobile phone controllable smoke alarm, Hence my Wiki link

You will have to deal direct with a moderator to tidy up your stuff. Perhaps they might decide to recombinee your threads. Mordred I rather think that your list was not even 'in at the deep end' it looks rather like diving off the clifftop at Acapulco. 😀 So to start with sime simpler ideas : Thousands of years ago the ancient greek mathematicians had the idea of Axioms. These are statements that we accept without question. Euclid is famous for his 5 axioms of geometry. Over the years philosophers widened the idea to other disciplines, especially logic, using the term Premises. By combining these statements in various ways, perhaps with further information, further statements can be deduced. Important small statements that may be subsequently used again and a gain are called Lemmas. The most important and larger statements are called Theorems. Obviously the worth of such schemes depends upon the wisdom of the original choice of axioms (see 6 below). The process of deduction is called Proof. Proof is really a test that a proposed statement is compatible with all the axioms. This works really well for mathematics and logic. In the last few hundred years a massive development in Sciences occurred. They tried to use the axioms and proof approach to science. But as noted in (4) mistakes occurred. The most famous was probably "That a heavy body will fall to Earth faster than a light one". Today Science does not have axioms and proofs. Science has Principles. The Principle of Relativity in Physics. Le Chatelier's Principle in Chemistry., Homeostasis in Biology etc https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Introductory_Biology_(CK-12)/01%3A_Introduction_to_Biology/1.05%3A_Principles_of_Biology#Homeostasis Principles are more like (well constructed) guidelines and subject to change in the light of new (and hopefully better) information. Unlike maths and logic where a new theorem must always be compatible with the all the axioms and other theorems of the subject an Hypothesis may run counter to some principle or introduce a totally new one. This brings us to the subject of what does Science do instead of Proof ? Science is the study of Nature, in its widest sense, so Science makes nature the ultimate arbiter of the worth or veracity of the hypothesis by direct testing. So direct testing showed conclusively that heavy bodies and light bodies fall at the same rate and Science (eventually) had to revise its original statement. A further test is checking that the outcome of a prediction made using the hypothesis conforms to observation. ~So that's a 10 point good start. Next time I will take you on a lightning trip through the principle that controls most events in the universe, from galaxies to gravity to ...... So please ask any questions about my 10 points (twice as many as New York had) and answer this one question. What do you understand by 'energy' ?

Better question than your first version. Note @exchemist excellent reply that the superconductor is on the ground since you require all that extra apparatus to generate and maintain superconducting. +1 The answer to your question comes directly from school mechanics 101. The upward force on the hovering object equals the downward force on the apparatus equals the weight of the hovering object. This must be so by the definition of hovering.

Gee Mordred that's enough homework for twenty years. 😀

I already gave the correct reference to improper rotations. Here is a link to what @joigus were discussing https://physics.stackexchange.com/questions/16378/why-are-infinitesimal-rotations-commutative-whereas-finite-rotations-are-not I agree with your answer. I'm still learning how to respond properly, I guess you use the quotes. I thought you did it with the next post. Thank you. I assume you understand what stochastic and iterative processes are so here is an example from this book, relating random variables to rotations, which you should appreciate with your electronics/ programming background.

Really ? You asked specific question and I gave you the only specific answer. Yet you haven't proffered the courtesy of any response. Am I wasting my time ?