studiot

@cgolding. I'm sorry you chose to ignore the post from soneone who has actually moved such objects. go well

Whilst such movements are not everyday occurrences, they are not unusual in modern civil engineering. I recall recent projects to 1) Remove a 2,500 tonne concrete bridge deck, rotate it through 90 parallel to the motorway lower it onto bogies on the M5 motorway and then drive it away up the motorway. 2) Jack up the A38 Plymouth viaduct and move it sideways nearly half a mile to realign the road. I don't know the weight of this viaduct, but it must have been of the order of 10 times that of the other bridge.

Before you ask this question you should ask "Is the universe finite or infinite" since the terms only have meaning and validity in finite systems.

Well I'm sorry if you took it that way. I meant that you seem skeptical of string theory and mtheory (as I am), not science in general. go well

You should both read the works of Alfven and Lerner. One of these won a Nobel for his input.

Gosh a sceptic. You are obviously young and were missed out in the 'pogrom'. I will send the indoctrination squad round immediately.

This is both wrong and right, but really useful to point out the wider meaning of the word evolution. So for instance in sailing the term is used in the sense of 'An ordered development, perhaps to a conclusion' This this is the exact opposite from Darwinian evolution which unfortunately is so often misrepresented as implying some purpose or advantage behind the changes, which in the case of Darwinianism are truly random.

No fields, potential wells or other restrictions are defined other than what the particle 'creates' by virtue of its own existence in an otherwise empty unbounded universe.

Our universe contains some (unknown) very large number of particles. It is also our tenet that our laws of physics should be such as to also apply to a universe with a different number of particles. That is they should be invariant to the number of particles. So what is motion (ie what are the observables and what do they mean) for a universe containing a single particle?

Photons and EMF are very different things. Further the word range does not associate well with the concept of EMF.

The 'energy' of a single particle in an otherwise empty universe is indeterminate.

More to the point any such theory not only has to work with our universe as it is it also has to work with a less complicated model. The simplest non empty model is a universe with only one particle. For a universe with only one particle, motion is meaningless.

Please is a very good word +1 If a and b are both vectors then both a . b and a x b can equal zero (though not simultaneously) without either a or b (or both) being equal to zero. Do you know what these imply?

Thanks all

Yet another thread with no apparent point or question. The above extract from the rules (reproduced more fully below) outline my objections to this type of post very clearly. As Juanrrga said What is your point?

I would much rather they had determined that £1 notes, £10 notes, £100 notes and £1000 notes were one and the same.

Just to add to what juanrga has told you, You seem confused between a state and a configuration. Configurations are geometrical arrangements in 1, 2 or 3 dimensions that can have mirror images. States are not. They are a point on a graph, representing the value of some chosen function or set of functions at some chosen point in time or space or even some generalised variable. The participating forms in benzene resonance are configurations.

This is the first I have seen of this thread and it looks most interesting. Thanks Daedalus

Stubborn is not the word or phrase I'd employ. But then I'm just the only one here trying to work through a real practical explanation for what others have told you without detailed justification. As to the universal application of a principle there are many things that no application of energy will enable. For example take a shovel of calcium carbonate in equilibrium with a saturated solution of the same. No amount of energy input will turn your plaster into plaster solution because calcium carbonate is basically insoluble.

Ronald Hyde : Your direct answer to my question:- No, it's not that I'm not interested, not at all. I would not in the least deny their truth. It's that they're all derivative. Yet when challenged about this you deny it and state quite the opposite Because you were so busy avoiding hearing what others say you missed the most important point of what I wrote in my post. It is well established that an oscillation or vibration occurs by exchanging energy back and fore within the vibrating medium. So with a pendulum for instance the energy is constantly swopped back and fore between kinetic and potential energy, but the total is constant. Further more there has to be enough energy in the system for the system to reach max velocity and max stored potential energy. Now I mentioned that the delocalisation energy of benzene is 155 kJ/mole. You did not respond. This means that the sum of the bond energies of three carbon - carbon double bonds, three carbon-carbon single bonds and six carbon-hydrogen bonds exceeds the measured total bond energy of benzene by 155kJ/mole. If the delocalisation (also called resonance) was achieved by switching back and fore between states then the system would have to have the energy to exist in those states, however briefly. But it does not possess enough energy to actually exist in a Kekule state. Ergo it must exist in some other state. As to the lesser point that you also initially chose to ignore, although were finally pushed to admit you did not understand. The Kekule formula is not the only conceivable arrangement using classical single/double bond configurations. These other lesser ones also contribute to the delocalisation (resonance) effect. I am, however glad you understood my point about acetoacetic acid. This can be expanded in a discussion of resonance (which affects only electrons) and other processes which affect the nuclear part of the molecule.

The problem with guessing what someone else means is that you can easily guess wrongly, as you have done here. You have guessed wrongly because you have absolutely no idea what I mean and instead of the asking the simple and sensible question 'Please explain further?' or 'what do you mean?' or somesuch You have the appalling arrogance to dimiss my comments as 'derivative' - whatever that means. Do you understand the term 'delocalisation energy', which for benzene is 155 kjoules per mole. How would you measure this ? Do you know what the LCAO method is or what a basis means? Do you know what the [math]{\psi _B}[/math] wavefunctions represent or what their contribution is to the resonance mechanism? Finally do you know why acetoacetic acid is not a resonance structure, but a tuatomeric compound? If you like what is the esential difference between a tautomeric substance and a resonance substance? [math]C{H_3}.CO.C{H_2}.COO{C_2}{H_5}\; \Leftrightarrow \;C{H_3}.C(OH):CH.COO{C_2}{H_5}[/math] Oh and by the way the correct term for what happens in ammonia or the ammonium ion is hybridisation not resonance.

I apologise the logarithm should only be to the base e. Some texts (including the table I looked up), and evidently Wolfram Alpha mean the natural log when they write log, something to watch out for. BTW the WA links you gave do not work for me. With that in mind you ands WA agree on the answer.

Firstly you mean differentiate not derive. To derive means develop a formula for, which is what I now do [math]\begin{array}{l} y = {a^x} \\ \log y = x\log a \\ \frac{1}{y}\frac{{dy}}{{dx}} = \log a \\ \frac{{dy}}{{dx}} = {a^x}\log a \\ \end{array}[/math] Does this help? Note it does not matter what base you logs are to the formula still works

So when offered further more detailed information about a subject why are you not interested?

So why did you start this thread? What do you want to know?