studiot

I haven't missed any point. I have tried to make the point that hydroponics has little or nothing to do with the use of rotting leaves and other vegetable matter., which this thread is about. I am sorry if that was not clear but I see that Seth has explained it better himself. You are however correct in that the late 20th century has brought in a new technology to do with this in tthe guise of biodigestors. The spread of these has been accelerated by the push for recycling. Also a candidate for newer technology would be the making of silage. Although this is to do with stems as much as leaves. I wonder if my use of the words compost and rotting are causing confusion. Leaves will eventually rot whether you compost them or not. Your mention of 'milling' makes me wonder if you are referring to the used of machine shredders ? Certainly many gardeners use these to create a finer consistency of the materials, which can include stems and twigs and bark. This produces a finer more even consistency material for 'mulching'. The main purpose of mulching is weed suppression and moisture retention, not fertiliser although the shredded material (pulverized ?) eventually rots down to return any nutrients to the soil. Equally this process accelerates the rotting. So I don't see how you can divorce the two.

This question deserves a thread all to itself. I think any definition of emergent v fundamantal has the inherent problem/danger of becoming self referential. This is because before (in time) anything can emerge the 'more fundamental' thing must already exist. So how does the time bit of spacetime fit in ?

OK the definition of superposition is largely correct but rather akward to work with and not totally correct. In particular the physical phenomena do not have to be of the same type and the examples given could be difficul to apply without further informatuon. Two or more causative or controlling agents act on the same body or in the same region of space or in the same electrical circuit they are siad to be in superposition. a) So two voltage sources, one alternating and one direct, acting on the same electrical resistor are in electrical superposition. b) Gravity and the thrust from a rocket engine are in mechanical superposition. c) Two waves acting along a single string produce a combined wave by acting in superposition. An orchestra has many instuments acting in superposition to produce music in the concert hall. These are examples of classical superposition. d) Two quantum wavefunctions acting in the same space are may be in quantum superposition or they may not be depending upon circumstances. Examples a and b are what are called linear superposition. This is good because you can simply add up the effects of each acting alone. Example c may be linear or non-linear. You cannot simply add the wavelengths as suggested by your dictionary. So back to your question. Yes there is a region of space, but there are no causative agents acting. An observation, calculation, measurement or reckoning is not a causative agent. I said reckoning because direct observation or direct measurement of relativistic effects are generally not possible. The effects have to be deduced from indirect measurements (called observables) The two moving observers cannot directly observe the length they have to calculate or reckon it using the correct formulae for the frame concerned. Of course relativity also says that a third observer located in the frame of the two points, frame 1 cannot directly observe what the other two observers see. Does this help ?

Thank you, it's good to have a rational discussion with someone.

Actually there are three different reckonings to the distance between the two particles. One corresponding to each of the three frames I listed. Why do you think I said reckonings not observations or measurements ? And why do you not cooperate by answering my questions ? I am trying to find out what you understand superposition to be, so that I can help you simply. Because it is not. Because the situation you describe does not conform to the standard definition of superposition. But I am not going to go through another 5 pages of argument with you about a definition which is not mine or yours to make.

The short answer to the headline question is no. I don't know what you understand by superposition - perhaps you'd like to tell us. Quite simply there are three frames involved in your scenario. 1) The frame of the two particles. Because they are in the same frame they must be at rest with respect to each other. 2) The frame of observer1 3) The frame of observer2 If frames 2 and 3 have different velocities relative to frame 1 then they will reckon the distance between the particles as being different.

But then it wouldn't all be waste heat would it ?

Thanks for this. +1 As regards checking, might it not be prudent to simply persuade a bunch of folks who have tested omicron positive with a pcr or a spit test to take a lateral flow in the interests of society?

I can't remember whether it was epside 8, 9 or 10 where they stated exactly this in so many words. "...the only life possible outside Earth would be an artificial intelligence." I am trying not to spoil the series for those who might wish to watch as it was really quite good and explored many issues in a way that only SF can. Some ideas were drawn from 'A space oddesy' - but were , in my opinion, much better done. I think oddesy was much overrated.

Do you know of any solid evidence (yet) that confirms whether or not a lateral flow test does detect the new omicron variant ? That is does it produce a positive result even if it doesn't distinguish variants?

The episodes are only 25 minutes long. The BBC has two series of 10 episodes each. So far I have only watched the first series.

I liked the bit about using D'Alembert's statistical mistake with the two coins. Thanks a lot for the reference. +1

But the decisions also have to be right when they are taken. The UK track record here is not so good. And not only decisions but also the right examples set. IMHO, when he stood up yesterday to announce the new restrictions to come into effect next Tuesday, Boris should have also said, "However I am wearing a mask right now as are the two non speakers with me, there is no need to wait a week for the regulations to become law, everyone could choose to do it right now".

The feasibility is debatable and that just kicks the can down the road about life starting. The French production I mentioned has an interesting take on this aspect.

It is a pity that stormloop hasn't participated further in this discussion as it has raised some interesting answers, albeit rather spread out. I hope he or she is OK. I am currently watching a French scifi series on BBC iPlayer called Missions. Missions is about the first few manned missions to Mars but underlying the day to day adventures one of the themes could belong in this thread. A latter day Bezos or Musk have come to the conclusion that the only life possible outside Eath would be an artificial intelligence. The consequences of this are worked out in the two series. The series is also interesting as it was made at/with the cooperation of the Museum of the Moving Image which I have mentioned before and which is worth a visit in its own right.

Yes this is perfectly true. But it is not an answer to Seth's question, which you quoted as you were responding to. I read Seth's 'neolithic technology' as the (ecologically good) use of leaves. This has actually nothing to do with hydroponics, unless you count the manufacture of what we used to call 'liquid manure'. I don't know if the trade name liquinure is still going. Ye, but I've never seen anyone till a forest. Ploughing or digging in green manure is quite different.

Keep digging +1

I am more than happy to learn something from anyone with more knowledge of biological classification than I have, my classification scheme is strictly of the common or gardening variery. So I call tomatoes salad veg, although they are actually fruit. +1

The question is asking you to solve the given differential equation for which the pdf = f(E,t) is a solution. I know less than nothing about python, but since the question asks for computer code, is it asking for a numerical solution ? I note part 1a specifically asks for an analytical integral. It is also worth noting that any solution is likely to be an exponential, since the second derivative is an exponential.

Great idea +1. It is worth distinguishing different types of vegetable material. I thought fungi go for the woody parts mostly. Moulds and smaller organisms go for the softer material. Some plants are all soft material, (perhaps roots apart). I was taught to use mustard as 'green manure'. This is planted before the desired crop and dug in green and whole not long before replanting. The practice is coming back into fashion with farmers as a soil conditioner. it prevents leaving bare earth to suffer soid leaching. But many plants have woody parts, stems, branches, spikes, needles etc. Some leaves also have a waxy coating or other thick coating which makes them doubly hard to rot down. It is not only nitrogen that counts. Pine needles create a very acid layer which suppresses most other plants and acidifies the soil when they eventually rot. Pine needle leaf mould is not good to add to most domestic or agricultural soils. Vegetable production especially needs less acidity, which is why we traditionally lime the soil. Yes they can take longer than say carrot tops or grass cuttings, about the same time as straw for instance. However a small amount of nitrogen loss is often not a problem, except to nitrogen greedy plants like rhubarb or asparagus. And the fact that they take longer makes them an ideal weed suppression mulch. Some use straw. Traditionally straw performs this function in strawberry beds as well as keeping the berries off the gorund. Not sure why they would argue with Seth's statement ?

Thanks good point.

I have found when using either the quote function from the input toolbar or the quote function for a previous post or part of one that you need to exit the editor's setting by hitting return a few times untl your cursor is a few lines clear of the quoted passage. I also find that doing this to separate several quotes is a good idea as sometimes the limits overlay each other.

Yes I'm aware of that, but Einstein was still pretty general. He used 'pulses' or flashes of light not continuous waves. That could just as easily have been pulses of 'superfast lentil pudding', for all the bearing it had on his argument. (pun intended). It was the pulses that were important. And, of course, I think you deal with pulses of laser light today? No offence to tar but I think he is trying to run before he can walk. Bondi's (excellent) book is aimed at folks in his situation. But it still requires careful reading as with any serious subject. Here is the preface explaining his approach, if you haven't seen it.

I think talking (arguing) about photons is pointless in Relativity. Photons are only part of light's story anyway. Einstein in his original paper went to great lengths to avoid (do without) the actual mechanism of light and its propagation. He was well aware of the difficulties about the nature of light faced by physicists of that time. His derivation would still hold good if light were actually found to be something else entirely. These days we tend to shorcut this because we know much more about the nature of light. But focusing on light is not the way to Relativity IMHO. (pun intended)

Partly depends on the chemistry of the fuel. Hydrazine is particularly bad as it produces oxides of nitrogen. Here is a NASA video - warning it's over 20 minutes long.