studiot

The point is that in any physically substantial environment whatsoever ( I daren't say medium though that is the usual phrase) the transmission of light leads to two beams or rays. The main beam passes through, diminishing according to the Beer Lambert or similar law. Spectrophotometers mainly use this beam. The scattered ray, off at some angle, is the basis of Raman spectroscopy, which is also used in chemical analysis. Scattering is definitely something to think about, but it occurs when there's an abrupt change in media with an associated change in refractive index. We're considering a smooth, continuous gradation so I'm not sure how optics would normally handle that. Also, the Einstein Lens apparently doesn't differentiate by wavelength so perhaps spacetime neither disperses nor scatters as a "medium". I do appreciate the input, so thank-you. There is no change in media, abrupt or otherwise, in a chemical sample in a spectrophotometer.

Will this do?

Aren't you overthinking this a bit ? The OP asked why is this so ? He had also correctly realised the all important distinction between work done on the system and work done by the system. Furthermore what sign do you attach to 'q' in an exothermic chemical reaction ? And is gravitational potential energy calculated as positive or negative?

Thank you for clarifying that point, I rather thought that was the case and it makes a huge difference. It means that your hypothesis can be discussed without reference to Relativity, at least initially. After all, Relativity is not the only effect in the Universe. So fundamentally we are considering the hypothesis that there exists a fourth spatial dimension. Given the title of your thread I can see your source of inspiration for this. Treatments of fluid dynamics is usually developed in the plane (ie two dimensions) and much useful work can indeed be done in this way. Flow patterns abound and formal mathematics using 'sources' and 'sinks' is available and works to explain and predict many phenomena in real fluids. Such 'sources' and 'sinks' invoke activity in an additional, unseen, spatial dimension to account for these phenomena. Typically the third dimension. So it is not unreasonable to investigate extending this notion to our 3D world by postulating a fourth spatial dimension. However such a postulate brings with it the need to investigate other phenomena a fourth dimension would also create. It is about 200 years since this notion was first clearly enunciated and some investigators have been looking for evidence ever since. To date, none has been found, where there ought to be some, for instance in the casting of 'shadows' by 4D objects. Two classic example of hypotheses that foundered on the rocks of failing to expain everything the hypothesis implied were The hypothesis that energy is some kind of fluid with special properties. and The nature of fire as evolving some special fluid. (Both failed fluid 'theories') So I hope this discussion can proceed without a courtroom inquisition of challenge and rebuttal.

Depends whether by 'evaluate' you mean measure or predict theoretically. The question only has meaning in terms of measuring the instantaneous power for a defined period of time and averaging it. The result will vary with the width of your time window.

The bel and decibel are defined in terms of the ratios of power levels not pressure levels. Obviously power can be related to a 'pressure' (or other variable depending upon the physical nature of the signal, which may be electric etc) but it is not necessary. Power levels do not depend upon whether the flow is turbulent or not.

I'll just quote this from your paper, before the moderators discuss the rules with you. No sir, that is an invalid statement. An acceleration has units, even if its value is constant. These units then make your later equation [math]x\left( 0 \right) = 0 = \frac{{{c^2}}}{{a_x^0}} + C[/math] dimensionally invalid. Note Due to a bug in the programming here you may need to click on the page refresh button in your browser to see the equation in my coding.

A question about a sign convention that leads to a lot of confusion. This is not the only instance multiple sign conventions in Science. In this case it is a result of History. Thermodynamics was originally developed by physical scientists and engineers. They were concerned with making machines (steam engines) for the industrial revolution. Steam engines are heat engines. That is they thought in terms of input (heat in the form of fuel) and output (work). Both of these were thought of as 'naturally being' positive quantities. So they wrote their version of the Law of Conservation of Energy (The First Law of Thermodynamics) as ΔU = q - w. Chemists came to the scene from a different point of view. They wanted all forms of energy to have the same sign, whichever side of the conservation appearance they appeared so they could present the equation as a sum on both sides of the equation. So they wrote their equation as ΔU = q + w. By then it was also realised that, although all the terms are energies, there is a difference between ΔU , which is a state variable of the system, and q and w which are exchange variables of the energies crossing the system boundary. So they tidied up by stating that all energies crossing the boundary from the system to the surroundings are negative and all energies passing from the surroundings to the system are positive. Now they could add them up, move them about in equations and between equations in other parts of Science in a consistent manner. It is an improved system But it shows the importance of knowing the sign convention in use and the equations that go with it. This last remark also applies to other such instances of multiple conventions such as those in Electricity, Elasticity and elsewhere.

And thank you for taking notice and laying out your posts to the benefit of all. +1 Looking through you paper, and the response from others, the nature of all four of your dimensions it is not immediately clear. This seems to already have caused confusion. Please confirm that this means four spatial dimensions plus time. ? An 'event' is characterised by a single time coordinate value in relativity. This is a special scientific use, different from its use in normal (English) context, as in "the Glastonbury Festival lasts 4/5 days." Hence some of the confusion. The thinking behind the hypothesis seems clear enough however.The big question is. Does it fit with known observations of the universe? I will wait for your answers before making further comment since they will determine their direction in realtion to fluid theory and relativity theory.

I think the authors may have fallen foul of what I call the 'ley lines argument.' But there is already a thread on this document. Perhaps someone can link to it, as Modred says, it is off topic here.

Because continuity is destroyed at every grain boundary. The curve is only 'piecewise continuous, and one condition that such a curve fits into the math of continuous functions is that there are a finite number of discontinuities. Yes SR and GR pay no respect to discrete mathematics. But the quantum solution to a totally free (ie isolated) particle is continuous. When we introduce the boundary conditions (usually zero at the boundary) we are looking for specific solutions that have zeros. We may also have to match first derivatives (this is one of the things Dirac did with his relativistic equation). It is granularity or continuity. This last bit is a bit of Physics or Engineering hand waving to make an approximation as close as desired. But, as any proper school of numerical maths teaches, the higher order the collocating function the more the function squiggles in between match/calibration points.

The point is that in any physically substantial environment whatsoever ( I daren't say medium though that is the usual phrase) the transmission of light leads to two beams or rays. The main beam passes through, diminishing according to the Beer Lambert or similar law. Spectrophotometers mainly use this beam. The scattered ray, off at some angle, is the basis of Raman spectroscopy, which is also used in chemical analysis.

I have a doctor friend who recently completed her totally online Msc in Pharmacokinetics at Edinburgh. I will ask her how her award worked, because I don't think she attended the ceremony.

There are some good questions here. +1 But take heart; no one else has fully answered them either. In particular there is no such thing as a quantum curve, since a curve is continuous. Nevertheless Mathematics can cope - it is Physics that lags. There is such a thing as Discrete Mathematics (sometimes called Concrete Mathematics) that applies to non continuous situations. There is even a well developed theory of integration and other calculus in Discrete Maths. Obviously it differs from the traditional Maths of Continuit - usually called Analysis. Continuity is closely allied to connectivity. There is such a thing as a 'disconnected curve' in Analysis. But no one knows the answer to the question is the physical universe continuous or granular (discrete) ?

You really are making things difficult for yourself so I will let you into a little secret (well two secrets actually) Firstly here is a physics calculation New members are allowed up to 5 posts in the first twenty four hours and after your first three we are still in the dark about your needs. Number of posts remaining today = (5 - number of posts wasted used) = (5 - 3) = 2 posts. Secondly Physicists are very lazy, Physicists like writing equation down, but it's Engineers that like doing calculations with them. This is OK since most of Engineering Science is actually Physics. And there are many excellent books of 'engineering calculations' about this, that and the other (mechanics, electrics, fluids, gas dynamics ......and so on.) What I am guessing you are looking for is what we call 'worked examples' These are really good for study as they help understand the subject and the mathematical statement of it. Also Physics is usually divided up into areas of study - Heat, light/optics, sound, electricity, mechancs, and so on. You need to learn a bit of each and carry them forward from one level to the next. From the beginning it is usual to start by learning what work and energy are and how the relate to forces. The student is then in a postion to study into these matters in relation to heat, electricity motion, and so on. A good book with lots of worked examples to make this start is Mechanics and Properties of Materials by Stephenson. This would be upper high school level stuff and into first year university. But it doesn't matter where you are in the scheme of things. Scienceforums will help you understand and calculate with either of the equations Strange mentioned, and many more besides.

Difficult to answer this without more information about where you are coming from. Please tell us 1) Do you know why there is a 'barrier' and and how does it work in an ordinary junction diode? 2) Have you seen the energy level model to explain tunnelling and why it occurs? 3) Have you seen or can you handle any maths to go with this? Finally it might be better to say electron tunnelling occurs in diodes, rather than the other way round.

Fluids is one of my subject areas so I have downloaded your paper to look at. But Please do not respond to members in the fashion of your quoted post. It is extremely difficult to sort out who said what and who replied what when they are all jumbled together. Using the forum quote function is best since it also alerts those you are quoting that you are replying (I use this facility a lot). Alternatively copy and paste into your own quote box, accessed from the inverted commas on the input box. If you are having trouble with this ask and you will be helped. Thank you.

I would just like to point out here that Einstein did not refer to photon's or quantum theory when he introduced relativity and light clocks. Indeed he carefully avoided the mechanism of light until he had included it in his maths where he always discussed a light pulse. The light pulse being the instantaneous 'front' of whatever constitutes a travelling light ray. 'Das lichtquant' was another paper, directed at and confined to other effects.

That was why I posted it. Now you have that we can move on. You are playing about with 'clay minerals'. These have special properties in soil mechanics on account of the ionic charges. One of these is the ability to hold water in quite large quantities.

Fun ? 🤣

I am not sure what you mean here. I can still see them when I log on to ScienceForums. Unless my links also contain code my access, which as I noted has run out for this month. The education department of the RSC publishes a number of pamphlets as electronic documents in pdf, which can be read or downloaded or bought from their website. One is a general guide to fertiliser specifications and calculations, the other is the recipe I mentioned. I cannot post the ideal mineral document (it is only two pages) here for copyright reasons, but I can let you have a copy if you can send a suitable email address via private message.

It would be useful to know what level you are studying Physics at?

Hello Trestone, I see that you first posted a proposal for something called layer logic before I was a member. Today Search engines don'e sem to have given the idea much if any traction. So perhaps I can ask if the layer logic is anything like what is called the 'layer model' in computing ? I note your notation/presentation seems to be an adaptation of normal mathematics and (computer) programming. https://www.google.co.uk/search?source=hp&ei=U1nBXtulM5rAgwf3_LvIBw&q=computing+layer+model&oq=computing+layer+model&gs_lcp=CgZwc3ktYWIQAzIFCCEQoAE6AggAOgUIABCDAToGCAAQFhAeUMQLWPwnYPAsaABwAHgBgAHoBIgBliOSAQs0LjYuMi4yLjEuM5gBAKABAaoBB2d3cy13aXo&sclient=psy-ab&ved=0ahUKEwibm56qnLvpAhUa4OAKHXf-DnkQ4dUDCAg&uact=5

This is useful, I can tell you more now. Firstly greensand is not a single mineral or rock. It is a class of stratigraphy (naming and ordering the layers) which contains a range of rocks and minerals. Greensands and greenmuds and widely distributed throughout the world. They have been formed at the bottom of continential shelves (under the sea) since ancient times (several billion years ago). So they are found incorporated in the strata on all continents today. The strata vary in colour from dark brown to the dark green colour that gives them their name. Both the green and the brown come from a mineral called glauconite which is a complicated potassiun-ferro silicate. This contains traces of radioactive potassium 40K, which allows radiometric dating. The stuff in your supply was dates from the Cretaceous period in the SouthEast of England between 115 and 95 million years ago. Other supplies may date from very different times. Ground up it has been used as a 'low grade' fertiliser for centuries. Low grade means the nutrient minerals are not as concentrated as modern industrial concoctions. Nor will they be as balanced to your needs. Did you note one of the RSC links I gave was to their recipe for the 'ideal' mineral mix that (they say) contains everything plants require? Here are some more links with more information The first one refers specifically to your English source, but is a paid for paper. https://www.sciencedirect.com/science/article/abs/pii/S0016787860800144 This free one refers to the US, where they say there is only one mine now in operation. https://pubs.usgs.gov/bul/0660b/report.pdf These are horticultural and aquacultural references. https://www.thespruce.com/organic-fertilizer-green-sand-2539762 https://www.epicgardening.com/glauconite-greensand/ https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/using-glauconite-greensand.htm

'Represent' is OK. but it is vitally important to remember that any representation (often called a model in Scinece) is not the same as the real thing being represented. The only thing that has all the same characteristics and no others is the thing itself. So the representation is only valid if you are modelling a characteristic common to both.