studiot

Thanks for the reply, but the Luddite issue was different. Two people can't wear the same jumper. There will always be a need for roughly the same number of jumpers as people. If an AI can reuse the same image again and again for different purposes (as was done in later Terminators) there is no need for so many actors in future.

How does this answer the question in the OP, which was "explain why this may be the case" ? Actually the question was full of woolly qualifying statements such as may be etc., as is the article TheVat linked to I agree with Seth that the words in the OP were not well posed and the woolly words are not really meat for GCSE which is the first serious science exam taken in British schools at age 15/16. +1 Possibly a better article for this purpose is from Scientific American https://www.scientificamerican.com/article/what-causes-a-fever/ which offers simple simple but useful information Thanks also MrMack (+1) for pointing out that sometimes we wish to raise body temperature in a controlled way. Hot paraffin wax baths were once used as a cancer treatment, and are still used today for other purposes.eg https://www.medicalnewstoday.com/articles/paraffin-bath-for-arthritis There's lots more on the net. But for GCSE, I would expect the student to be able to ask themselves the question The question says "You may get a temperature" - that may again. How (by what means) does the body temperature rise? Which leads straight into the material I originally posted. General Science 101 "A body's temperature rises when heat is input or generated internally."

Possibly a lesser known bone of contention is the following claim (my emboldening) Comments and thoughts ?

Are these the actual words of the question or your reading of something? I ask because they are not strictly accurate. Yes you may 'get a temperature' from a disease but it does not have to be an infectious one. Arthritis would be a common example. Of course you always 'have a temperature' which may be raised or lowered from normal for many reasons. So strictly, scientifically speaking you should refer to raised, lowered or normal. You can also get a raised temperature from physical exertion. All these mechanisms of temperate increase have something in common. Simply, but scientifically they are due to an increase in metabolic rate, but for different reasons. Most biochemical processes generate or release energy as heat. So the faster the process is going the more heat is released. The body also has mechanisms for temperature regulation (sweating) , so some form of balance is struck. Biochemical processes also have an 'optimum' temperature and both the body's own processes and that of many infectious agents have similar optima. So as the body metabolism works harder in fighting the infection, the body temperterature begins to rise. Sometimes sweating is enough to control this sometimes it is a more runaway action we call a fever, depending upon whether the infection or the body is winning. Helping the body cool artificially increases its chances of success over that of the infectio. Additionally other body processes can also proceed more normally as they are also adversely affected by raised temperatures.

OK so we are going to work from general experience What holds up bouncy castles, lilos, air beds, bicycle tyres and the like ? I am going to answer this in a spoiler considering the circumstances and it is general science you will need to know something about. Now associated with the process we call osmosis, there is an increase in pressure of a fluid, which is not air. What do you think this fluid is ? You have obviously found your way round this site very well. Did you read any of the rules ? Two things. Firstly new members are allowed 5 posts in their first 24 hours. This is an effective impediment to the bad guys. Since you have one left, think very carefully before you reply. After one day you can have as many posts as you like and conversation can continue normally. Secondly, the homework section has some special rules. We are not allowed to just tell you the answer, as we could in the biology section. So is this actual homework or just part of your catching up. There are good folks here who would encourage that.

This is not a personal criticism, but can you give us some context to the biology questions ? I ask this because, from your comments around both your biology questions, you do not seem to have the General Science knowledge to be able to attempt them.

First let me say that everything stringy said is correct. However it is not the answer to your question. Animals and plants are 70% to 80% water. And what is food ? Largely dead plant and animal material. So it contains a substantial amount of water, even if dried out by cooking, and apparantly 'solid'. With regard to the olive oil, it will contain some water, but is it a solid ? Think also of gardening. You purchase a pH meter with a probe you shove into the 'solid' soil and get a reading for the soil pH. Why? Because of stringy's ions in the incorporated water. So the Quora respondent is just plain wrong in this instance.

I don't know the details of the naval architecture of the Titan. But it's design must be (or perhaps should have been ?) subject to the same stability/bouyancy considerations as other submersibles. The current speculation about the effect of loss of volume due to compression is relevant here. A general submersible is compressed as it descends and the effects are neither negligible on bouyancy nor stability. These are separate considerations. In order to maintain stability the distribution of the variable mass component must be considered. Some bouyancy force is derived not from Archimedes but from lift due to the motion of the hydroplanes. These must be correct or the sub will enter an uncontrollable nose dive. https://www.marineinsight.com/naval-architecture/understanding-stability-submarine/

Your list is woefully short, anyone would think we had not proceeded down to the DNA level since linneaus in 1700. eg the stabyhoun is a dog but it is picked out from other dogs by its genetics (it is also rare about 4000 in the world) But it is accepted as a separate category by the relevant authorities. https://studenttheses.uu.nl/bitstream/handle/20.500.12932/21271/PDA_LMVlutters_definitief.pdf

Good advice +1 Thank you for you confidence and for that useful information explaining what you want to do. As Seth says, the quadratic formula you quote comes from a specific solutions to Fick's 2nd law, using what is known as the error function. I see this as a longer term project for you than just a few days, or even weeks, but I am delighted than someone wants to get their hands dirty with an actual lab experiment. This is really Physical Chemistry or even Electro Chemistry, but sadly we don't have categories for these here. Anyway I was going to elaborate on my previous post with some more maths and elctrochemistry references but I will be away for a couple of days. If I posted the development details of Fick's 2 laws and the electrochemistry at what level can you handle it ?

Quite frankly I don't know and I don't care. The classification scheme is not in English, Russian or Hebrew, but is set by international agreement. The point is that I could ask the same question in any language. The classification scheme is a victim of its own rigidity. I believe you correctly recently pointed out to someone that a woodlouse has too many legs to be an insect. Now transfer that thinking to the classification of dogs. Somewhere at the head of that classification scheme you will be told that a dog is a four legged animal with or without tail, hair etc etc. Somewhere near the bottom you will find different kinds of dog. Choose one of the rare kinds with maybe 1000 examples throughout the world. Call it a bow-wow. Now consider the following. There exists a small percentage of dogs with only 3 or 2 legs. Sometimes this is a result of accident, sometimes disease, some are just born that way. In a small population like bow-wows a small incidence factor will lead to there sometimes being 2 legged bow-wows and sometimes not So in the times when there are no 2 legged bow-wows are they extinct ? We have already seen simplistic rigid definitions that would suggest this is the case.

Look up the difference between algebraic and transcendental. Algebraic Versus Transcendental Objects | Britannica

I also think there is a link between the classification scheme and the definition of words, especially ones like extinguish or extinct. But I think it is just more subtle, yet far reaching then MrMack said

Jawohl, plus eins.

In turn I am sorry if I was a bit harsh. As regards mathematical set theory I only said biological taxons to be similar, I did not say they were the same. The similarity I was meant refers to the idea that they are both head of a chain of 'trickle down' classifications. As far as I can see your comment, though true, has nothing to do with this thread. The main other definition I was referring to was about the use of the words extinct and extinguish in Science. Did you read the Wiki article I linked to ? One important point it made was that taxonomists themselves can't agree these classification schemes. So perhaps you can explain why there are many 'extinct' volcanoes in our solar system, or what the'extinction coefficient in Physics, Optics and Physical Chemistry means, following the 'definition' that has been laid down several times in this thread.

Since you chose to use ridicule in answer to an honest question but ignored the rest of my comments on definitions, I take it you agree with the rest of those definitions ? LOL +1

This seems pretty general to me, allowing that biologists do not use the mathe specific term 'group'. Basically it seems to say " A bunch of the things we are dealing with" Why do you think it is not similar to a set in maths ?

Thank you for the brief exposition about biological terminology. I'm very shaky in that regard and it has helped me understand the argument. +1 Thank you for this summary of your thoughts. Referring also to some of your other comments on the subject I can see where you are coming from as well so+1 also. Some of the terms referred to here are more completely defined than others, Taxon for instance seems to me to be akin to a set in maths and is a very general term. But extinct and extinguish are more specifically defined but I can think of other sciences, eg Geology, Materials Science and also Physics which have somewhat different definitions. Extinct can also mean inactive and extinguish can also mean reduce, and we classify self extinguishing materials. None necessarily refer to there no longer an existing example of that which has undergone the process. Then upshot of all this is that I often say it is a good idea to agree what definition of a term you will be working with before starting a discussion otherwise the discussion becomes about the definition as opposed to the original subject.

I have very scanty knowledge of biochemistry, mainly through reaction kinetics, so I am only guessing what Amy is after, I suspect she has mixed up some terminology somewhere, hence my questions. Anyway here is a short discussion about the maths, set at upper high school level calculus. The diffusion equation and the wave equation connect the distribution in space and time of some quantity and it derivatives with respect to space and time. The 'solution'' of the equation is an algebraic equation describing the values of this function in time and/or space. The derivatives involved are first and second derivatives. The connection enables the evolution in time of a system obeying these equations to be determined. That is the spatial distribution at a given time t. In general we are looking for continuous functions so functions such as x = t2 and x = sin(t) are acceptable but x = tan(t) is not x = t2 is not periodic, but x = sin(t) and x = tan(t) are periodic. However x = tan(t) is discounted as it is non continuous. OK so the first derivative will be continuous (but may be zero). For periodicity to occur there must be 'turning points'. This involve the second derivative being zero at the points. Further there must be more than one turning point x = t2 has one turning point but this is clearly not enough to generate periodicity. Now the wave equation involves only second derivatives, So it is not surprising that periodic solutions predominate. The diffusion equation involves both first and second derivatives. So it nis not surprising that non periodic solutions occur most frequently in practice. But the periodicity or non periodicity is built right into the equation it is not a separate cake as chenbeier puts it. I hope this helps somebody.

Stand next to it and smile please - you are being photographed. 🙂 +1

The diffusion equation is not only impossible to solve, it is actually meaningless without the boundary conditions, (and I include initial conditions in this). The link Amy provided pays attention to this and describes in some detail some of the possible circumstances including multiple sources and/ or sinks both time and space and the possibility of both diffusing and transmission media interacting. It is true that the simple quadratic formula it calculates refers to a single source with no sinks and and an unbounded transmission medium. Thus it is a very simplistic formula (It is not the diffusion equation) which simply comes up with a rough estimate of how far (x) a diffusing medium would get in time (D), all other things being equal. but it depends upon these conditions which are part of the diffusion equation, not something separate from it. To see how diffusion can lead to chemical oscillation read this

@chenbeier @exchemist Surely you should also consider the boundary conditions. Even the simple diffusion equation has periodic solutions with the right conditions. There are plenty of learned maths papers on the subject. eg Diffusion equation if f and φ are periodic the solution is also periodic - Mathematics Stack Exchange Periodic solutions in reaction–diffusion equations with time delay - ScienceDirect The point is to find out from Amy what she is trying to do as I still don't follow this and she hasn't responded to my last post. Again a medical example, with more complicated conditions is the calculation of the rate and size of periodic dosing to achieve a 'steady state concentration' in the body. This also happens when considering Fourier solutions to the heat equation, which is a form of the simple diffusion equation. So @amy1vaulhausen, please, Why are you working with a physiological calculator and why are you measuring distance in light seconds ? What conditions are you setting

1) So you are saying there are only countably many positions in this first universe ? 2) Surely this depends upon how you define 'distance'. How does that work in a universe where distance is defined as the length of the peano curve between two points ?

We can all quote Cantor.

So would you like to explain this further ?