studiot

No problem https://spectrum.ieee.org/tech-talk/semiconductors/devices/quantum-entanglement-camera Thank you for providing this link, I had not heard about the experiment. How do you think the explanation given differs from the one Eise gave, if at all?

Since REg won't be with us for a while, perhaps never again, I was just wondering if you understood my point he was having so much trouble with ? do you consider truth/falsehood - right/wrong to be binary pairs?

You have only just joined SF but I forsee your stay being short since the new moderators have been given the ban gun.

My dear fellow, have a consoling glass of advocaat.

Here is another (dare I say real world?) example. A door is either shut or open, right? Well there is only one way for it to be definitely shut. BUT There are a myriad of ways it can be 'open' yet no allow passage through the doorway. And doors have yet another level, not possessed by taps. Suppose this door is the fron door for some little old lady and has a security chain. When she uses this to see who is there, is the door open or shut?

Thank you. And yet there is a world of difference between the state 'on' and the state 'off' in that there is a huge range from drip to trickle to running to full bore for the on state but there is no such range available to the off state. [philosophical aside] I all to often see folks trying to create some argument categorising a binary choice by defining the wrong quantity of a pair first , say xxx, (infinity and finite are good examples) and the other one as nonxxx. So here the correct choice is to define 'off' and everything else is 'not off' Doing it the other way round leads to logical difficulties [/aside]

When you get there any good electrical engineering textbook will offer the formula for F, the force between the plates as [math]{\rm{F = }}\frac{{\rm{1}}}{{\rm{2}}}{{\rm{\varepsilon }}_{\rm{0}}}{{\rm{\varepsilon }}_{\rm{r}}}{\rm{A(Potential}}\;{\rm{gradient}}\;{\rm{in}}\;{\rm{volts}}\;{\rm{per}}\;{\rm{metre)}}[/math] Where A is the area the epsilons have the usual values and the potential gradient very cleary depends upon the distance between the plates.

Ok. Again, the purported demonstration eludes me. Would you agree that the tap on my basin can be on or off ? Someone understands me +1

There are several nice one liners of explanation from others here who already have lots of green points. So I am picking Eise to award +1 to for an exceptionally clear explanation of entanglement. @ Quiet, I suggest you read up on displacement current (in capacitors). That has the local speed of light.

Possibly but I think you exaggerate by asking about towns in the plural. You need to be more specific in your detail.

Good morning Reg. I hope you slept well. Once again you are ignoring my response to this assertion, perhaps because you have no answer I really can't tell. It was, after all part of your conversation with me, not other members. And once again I assert that I do not accept it because it relies on there only being a simple binary choice available and I have already fully demonstrated that that is not the case.

Why?

Hello, Hugo and welcome to ScienceForums. Congratulations on your excellent English. - I hope you can understand themy answer. Part of a high school project is to discover what is possible and what is not. So even a negative answer can be a good one. There are no good ways to store electricity. Even in a battery it is converted to something else for storage. By something else I mean another form of energy. So for storage you need to widen your search. Google Dinorwic and Cruachan.

Yea that's the idea. Your sketch slides up and down the y axis (but not left or right) according to teh value of a. Now look at your graph of y = x3 -3x + a You are asked for the limits where there is one negative and two positive roots. First the negative root. What happens as your sketch slide downwards? (a negative) Eventually the maximum at x = -1 touches the x axis. If the modulus of a gets any bigger then that max is below the x axis and there is no root. Similarly for the minimum, at x = 1 So you need to determine the values of a for these conditions. If a lies outside these values there are not going to be the roots you are asked for.

You have said that already. What you didn't do was answer my question or even attempt it. Never mind. I didn't say the graph of y = x3 -3x and I should have. Right so get the graph of y = x3 -3x + 0 (that is with a = 0) Now if you add a = a positve value to this then it moves the sketch which way up or down the y axis? To do your sketch what happens to y if x is very large and negative? What happens if to y if x is very large and positive? What happens to y if x = 0? You have already identified two other points, x = 1 and x = -1

Has your studies included curve sketching? So sketch the graph of x3 -3x hint can this be factorised? now a is a 'constant' but we may choose different values of 'a' What do you think this does to your sketch?

Hello, Dr Neos can you fill in some more detail about your question? Non electrolytes fall broadly into two classes Polar (symmetrical molecules) and non polar (non spherical molecules or molecules such as carbon dioxide, which are linear so the polar effects cancel out) Such liquids still have a capacitance and can carry a displacement current, react to NMR machines and IR and other spectrometers, exhibit colligative properties and so on in the physical line. Equally in the chemical line you could experiment with comparative solvent action with different solutes, conduct fractional distillation So tell us more.

That is why I am fighting so hard to establish the 'level of know' - To prevent another discussion falling into that chasm. and yes I remember you posting your undergrad experience - obviously your university was different from mine as we were always to sozzled to remember debates though there were many 'philosophical' and other debates.

Since we don't know enough about the context and academic environment, asking your teaching assistant was a good plan. A pity she was not more forthcoming. In relation to John Cutherber's valuable comment a good indicator might be the marks. Is the question worth three marks or three half marks or just one mark?

Yes sleep well. Eise is correct in that you have to also examine the relationship between Language and Philosophy. You have found it necessary (and you are not alone) to introduce new words (language) to the discussion. 'Absolute certainty' in this case. Your comment only makes sense in the context of binary choices. I keep on banging the 'more complicated than binary' drum. It is physically possible for there to be an international conspiracy dating back centuries to hoodwink the non specialist in the classification of species (I don't even know if moths and butterflies are species or another term). But I consider the probability of that sceanrio to be vanishingly small. So I could be said to believe to the point of absolute certainty. But we then need to introduce the formal definition of probability and the fact that there are three different interpretations (all valid) for absolute certainty = probability of 1. Was it? It doesn't sound like that is what I understood, but then since I don't actually know what naive falsification is please clarify.

Please don't do this. It is most definitely and emphatically not what I proposed. It is also what I respectfully submit is what upsets many other responders here. It is also the reason I mentioned the 'level of know' and specifically excluded the interaction between thought processes and sensory perception. This is all a great shame as your following story piece is so much better thought out (not quite what I meant but sure we can talk about that). I won't quote it all since its quite long. Unfortunately your great mission to simplify has lead you to completely miss the difference in 'know' that I am trying to highlight. I apologise if my words are not up to this, but you are the self proclaimed Philosopher so should be better equipped than I am to tease the intended meaning from utterences. The point is that, by corroboration from various sources not least seeing tree diagrams of living creatures in general and insect in particular, I know that experts in this field (not just one dead friend) categorise butterflies and moths differently. The word of one dead friend (however expert) is not enough to say that I 'know'. Nor is it enough for me to believe (although the alleged word of one dead Jesus is enough for some to believe) I chose Red Admirals and Hawk Moths because I see a lot of these and have learned to identify them. There are many varieties that I could not distinguish as either a butterfly or a moth or even identify reliably as one of these varieties and not something else such as a damsel fly. (Are tapeworms insects?) So in summary these are facts: I know a Red Admiral when I see one, from repeated practical experience. By practical experience I can distinguish between a Red Admiral and a Hawk Moth. I believe almost to the extent of 'know' there is a difference between 'moth' and 'butterfly' from corroborative deduction and other indirect information. I know my depth of knowledge is insufficient to identify that difference (There are many small brown moths and butterflies on our moors I can't tell which is which; certainly the obvious differences between the Red Admiral and the Hawk Moth won't do) This is entirely in line with what I first said about this example. I hope the notion of 'depth of knowledge' bring clarification at the expense of reeuction in simplification. Thank you for finally answering my first question Yes, I think adding the missing word would improve the discussion. You may even find that further additions are warranted by the end of the discussion. Yes your answer (predictably) identifies the question of the definition of Forest (and tree). There is a whole discussion to be had about this in the light of my recent experiences. I read in Saturday's Times that London is officially a forest since it has more than 20% tree cover. Last week I was looking at the photographic records of the great storm of 1953 in NE Scotland. Flattened tree trunks everywhere, none standing. Is that still a Forest? But both this and the subsequent question was designed to elucidate Truth and the non binary natature of right and wrong. Most common usage of the statement "There are X Platonic solids" are used to actually mean there are only or exactly X. In fact there are more than three, therefore there are three but that in not all of them. Note again my theme that the method of reduction misses possibilities and that Nature and the Universe is more complicated than our categorisation. This is not to say that Nature does not have a place for things which actually fit the categories, just that she is constantly spring suprises on us.

Is this homework/coursework? You need more information because there may be little or no change depending upon the relative amounts (buffer solutions) Or there may be a change of pH all the way through from very low to very high, again depending upon the relative amounts.

If you are still referring to my line Then good we are agreed. (incidentally is see I wrote the level and I should have written this level or added appropriate to this thread - sorry) But I don't agree the next part that you follow it with. All this is true but irrelevant to my way of thinking. My example does not rely on artifices. Here is an expanded version 1) I can see a Red Admiral Butterfly and a Hawk Moth and can observe that there is sufficient obvious difference for me to be able to reliably distinguish one form the other. I am happy with what you call the standard definiton or name for both the phenomenon I observe as a Red Admiral and the phenomenon I observe as a Hawk Moth. So I know and have tested for myself that there are Red Admirals and Hawk Moths and they can be seen to be different. Furthermore it is irrelevant to my knowledge whether these things are really insects or just cleverly constructed drones or holograms. I still call the phenomena a Red Admiral or a Hawk moth. 3) However left to my own devices because I am not a specialist in this area I would not make a classification difference between moths and butterflies -they appear to be the same sort of insect to me. Yet I also know that specialists distinguish for reasons unknown to me and that I cannot therefore deploy. Since I am used to not having to personally verify every little thing that other specialists tell me I choose to believe that they are not kidding me. 2) (1) and (3) taken together show that I was giving butterflies and moths equal weight (to answer your question). 1, 2 & 3 also refer to the first mention of this example. So in summary the flow of thought is as follows Pure knowledge is something I know because I have personally verified (and yes I therefore also believe it) There are moths There are butterflies I do not know the difference for the reasons just outlined. But I believe there is a difference (pure belief) So I have tried to answer your questions and clarify my points, you can say if the came across. I also underlined a question, in my quote, you have yet to answer which was that you linked three notions in your original thesis but omitted 'belief', leaving the introduction of that notion till later. Surely there can be no hidden agenda in my asking why?

There's no need to 'go out on a limb' or be defensive. You now seem prepared to hold a reasoned discussion. Which means to me that we cooperate to reach the best answer. +1 Ok so what I meant by my first post. I agree with a lot of your thesis; I just think it is trying to make things too simple and I was generating examples of more complicated situations for discussion. This is the way discussion should work so thank you. What I was getting at there was simple to try to avoid the pointless argument of reality & existence along the lines of "I only know about my environment through my senses; how do I know I exist or what is see is real? etc etc " That discussion, in my opinion, does not belong in this thread. The use of pure knowledge, pure belief etc is just to offer the notion that I "know because I personally have verified it (the above existence comment not withstanding) " and "I believe because I want it to be that way" form ends of a scale or opposing notions but with some overlap as with a Venn diagram. This stuff arises because of complexity. The notions I know and I believe are sufficient and appropriate to the examples you are supplying, but I hold that there are more ecomplex examples where those are not enough. Does this help?

Would you like to re-examine this in the light of the following scenario? Jane, "How far is it from London to New York?" John, making a random guess although he knows that the atlantic is just over 3 thousand miles wide, "3257 miles". Would you then please re-examine my butterfly/moth example in the same light?