exchemist

OK, thanks. But I assume that, while a wave packet has amplitude centred around a specific location, the amplitude declines asymptotically on either side, i.e. does not strictly go to zero elsewhere. So this compact support issue is not really what I am asking about.

Yes but now you have to explain what compact support is. I’m only a chemist. 🙂 what does this mean physically for a wave packet?

That inequality is interesting. Does that imply that the persistence of a (classical) wave packet is shorter, the wider the range of Fourier components that make it up, i.e. its rate of dispersion is greater? I suppose in that case the extreme example would be a “packet” with only one component, which would then persist indefinitely. But then it would extend throughout space so would not be a localised packet any more. Which raises the question of whether there is another inequality relating the degree of the packet’s extension in space to bandwidth. Do you know?

Because what you said was wrong. It is trivially obvious that GR does not take into account the Uncertainty Principle. That is not because calculus is incompatible with it, which is the reason you gave, but because GR models phenomena for which the Uncertainty Principle is irrelevant. You then followed up your wrong assertion with further silly statements about non-commuting operators, for which I called you an idiot. I see no reason to revise that assessment.

Minor mistakes? You made some extraordinarily silly statements, including that calculus violates the Uncertainty Principle (when QM uses calculus all the time), that pressure and volume are non-commuting operators and so on. You thus gave other readers every reason to think you had no idea what you were talking about.

But we are not immune from cultural influences, advertising, etc. One example is that in France it is bad manners to drink soft drinks at table with food. In the USA it is the norm, at least in fast food joints. The practice is promoted by the fast food chains. I suspect that be one cause of obesity.

However, the better-regulated market economies have the means to deal with that, via their anti-monopoly provisions. You don’t need to define an acceptable profit margin, which is just as well since it is impossible to define in any sensible way across more than a handful of similar industries. Instead you ensure there is scope for competition and market collusion is forbidden by law.

To inflate their lungs, which are collapsed and full of fluid in the womb. They suffer a period of oxygen shortage when the cord ceases to supply oxygenated blood, and this both makes them uncomfortable and stimulates the breathing reflex. So they cry, clearing their lungs in the process. In fact, I now think I recall reading that a surfactant is secreted in the lungs of the foetus as the pregnancy approaches full term, which reduces the surface tension of the fluid in the developing lungs, making it easier to pull the surfaces apart to inflate them. The lack of this surfactant is one of the problems faced in the care of premature babies.

I think the point being made is that getting into space , which was what the post about planes was discussing, does not require reaching escape velocity, that’s all. Once you are in space, in Earth orbit (achievable at a speed well below escape velocity), you can use rockets or whatever to boost your spaceship to escape velocity, from whatever altitude the orbit is at, if that is what you want to do.

Yes that’s a fair point, certainly. However in the 1970s, the period I was referring to in which Marxism was so popular among humanities students, it was seen as a political programme, to be implemented by overthrow of the establishment in some way. If today it is merely seen as one lens, or axis, through which to view and analyse economics, that would allay the concerns of those like me that remember all the Marxist-inspired dictatorships of that earlier era. As it happens I think it is fairly unhelpful, in that it proposes an irreconcilable antagonism between capital and labour that strikes me - from my experience working in a European oil and gas major - as a bit antediluvian and simplistic. But it is true that some modern corporations like Amazon do seem to fit that analysis.

The link I supplied was evidence-based, was it not?

Hmm, I’m not sure your radical prescription is justified by the evidence: https://www.psychologytoday.com/us/blog/open-gently/201806/is-schizophrenia-hereditary-not-as-much-as-we-thought

The hint of underage sex will have resonance for Musk, given his own father’s, ahem, odd- though legal - arrangements….. But yes, the bust-up many of us predicted has finally happened and is more vitriolic than I for one had dreamed, heh, heh. Let’s hope the collapse in Tesla’s share price makes Musk think twice about more far-right meddling, or political funding, in Europe.

Your maternal grandfather was 9 yrs older than mine then. Nutmeg is interesting. Good with things like cauliflower. Can also go in mashed potatoes but you must be careful to use only a trace. I suspect in the days of simple roasts, a few condiments on the table were more of a requirement, to season and flavour the meat. Rosemary is good with lamb. I’m not sure how to use mace. Sage good with pork. I was delighted to find damsons on the market stall a couple of years ago, in early September. I bought a couple of kilos, stewed them up with sugar and froze them in batches. A real taste of childhood - and excellent with Greek yoghourt.

All of it is a sermon, moralising about the political condition of the world. My objection to so much of this Marxist stuff is one gets these sermons about how bad everything allegedly is but, as I have already pointed out, no practical political programme. Most importantly, there is no hint as to how any of the ideas can be put into practice by democratic choice at the ballot box. What would a Marxist candidate party’s manifesto look like? If, as you claim, Marxism can be compatible with democracy, there needs to be some engagement with that issue, especially in view of Marxism’s bad historical record wherever it has been tried. Historically, the route to a Marxist government has been violent revolution, followed by a one party state - and coercion of the population by secret police. Those of us old enough to remember the Soviet Bloc and Maoist China will need a lot of convincing that this particular leopard has changed its spots.

Interesting. Was this salt used domestically, in days gone by, as a flavouring? I must say I have never heard of such a thing.

No it isn’t at all. Fake implies deception.

There is no evidence here of any poll being “faked”. This just seems to be another of your unsupported assertions.

“Vinegar powder”? That must be utter nonsense. The essential ingredient of all vinegars is acetic acid, which even in pure form is liquid at RTP. The caster sugar explanation seems the most likely, especially since it would be applied in larger quantities than salt or pepper and thus would require a larger dispenser. My grandparents, who grew up in the Edwardian era, had a silver bowl for caster sugar with a special spoon with holes in, to allow you to shake caster sugar onto stewed fruit, which was a common dessert, often using cooking apples (Bramleys - very English), plums, damsons or gooseberries from the garden, or onto strawberries etc in season. People have rather given up making these cooked fruits, which tended to be rather acid and needed sugar to sweeten them. You almost never see gooseberries or damsons in the shops any more. By the way, you don’t mix mustard powder with vinegar. Just water. There used to be little silver, often lidded containers with blue glass inserts for mustard, together with a tiny spoon, as part of the cruet set. I have a couple, though I never use them. People no longer often serve joints of beef or ham, carved at table, which was their main use. ( I do mix up mustard from powder for ham, but tend to use ready-made Dijon mustard for beef, which has both oil and vinegar in it and has a milder taste. Mustard powder is also good in Welsh rabbit and cheese soufflés.)

Nice sermon, but again, nothing here to suggest a practical political programme that could be implemented without coercion of the people. It reminds me of the ideologically rigid speeches I used to hear at university in the 1970s. I’m sorry but I don’t see anything here that can take a 2025 liberal democratic society forward.

This still offers no argument for what Marxism has to offer us today, let alone any reason to suppose it would not lead, once again, to a one party police state that oppresses the people, as it has every time in history up to now. Because that, like it or not, is the historical “baggage” that Marxism carries. If you think it can be adopted in a liberal democracy, it will have to persuade the people to choose it voluntarily. For that, its dreadful historical record will have to be convincingly addressed.

Yes but we are in 2025 now. Appealing to the world of 150 years ago is of limited relevance in arguing what, if anything, Marxism has to offer us today. Such things as workers rights, health and safety at work laws, universal suffrage etc were not won for us by Marxists but by left of centre political parties, working within a parliamentary democracy.

It never has been historically, though.

Quite. The common feature is a political ideology that maintains it knows better what is good for people than the people know for themselves. So it imposes a system on society and uses coercion to achieve conformity. All Marxist states have done this, without exception. The means of coercion used naturally end up similar to those used by far right dictators. And thus the system often leads to similar cults of personality around an all powerful leader: Stalin, Mao, Enver Hoxha, Tito, Fidel Castro, Kim Il Sung…….. It is quite ridiculous for any Marxist today to ignore or deny the historical tendency of the ideology to breed such characters. There has never been a Marxist state that was also a liberal democracy. Any modern expression of Marxism needs to face its past and convince people of what it would do differently to prevent repetition. And I, for one, will take a lot of convincing.

So the greenish colour of the nodules is Fe(II), reduced from the general red/brown Fe(III) of the sandstone by the presence of hydrocarbons, as indicated by the high carbon content of the nodules.