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Hello. The slits should be at the top and the bottom of the pipe serves as a bowl. On another side the drain must be sloping. About 1 cm per meter. The accumulation of the water downstream means that by its level will cause water to pass through the slits. The gravel below the pipe is probably because if it touch the ground, it will plug and accumulate this mud in the drain. Be careful during your installation because it is said that for specific condition in agricultural spreading, the slits of the drain must be downwards!

Just a minute. Can we please first of all agree that I am not asking you to "elevate science and theories to the status of unquestioned absolute truth" ? Secondly, are you now willing to accept what I have been saying, which is that in science all "truths" are provisional, there are no "absolute truths" and that there is nothing that cannot be challenged? If we can agree this, we can proceed to the other points - if we both have the stamina.

It is refreshing to have a non controversial subject to discuss so +1 for introducing it. This is a worthwhile addition to the discussion, though it is not always necessary to have a slope or fall in the pipes, they are often laid this way and indeed in sloping ground it may not be avoidable. +1, making your reputation now neutral. 🙂 Externet has introduced two cases when non sealed pipework is used, both being for 'drainage' purposes and you have added a third in irrigation. Just to get irrigation out of the way quickly it is normally laid on the surface for the water to follow nature and trickle down into the soil. Clearly this would never be done in cases where the soil already contains sufficient water. Sufficient water does not mean saturation by the way. But Externet asked about 'French Drains' and in particular 'tiles'. The main purpose of the drainage is to lower the water table in both agricultural and ground engineering (foundations, basements etc) applications. The term French Drain refers to the entire system, not just the pipes. The water table is the boundary between saturated and non saturated soil (or rock) and has a posh name 'the phreatic surface'. Below the water table the ground is saturated and above it will generally still contain water but at lower concentration and so be unsaturated. If the water table is too high for part or all of the season then (some) crops will not grow satisfactorily. The original drain indeed used V shaped clayware tiles, laid upside down or apex at the top. These can be traced back to Roman times. These were not perforated but simply laid, butted in a line, at the bottom of a trench. The inverted V acted like a little roof, protecting an open space beneath, from being filled with soil Because the joints were 'open', water percolated into the open space and spread along the line. A network of such trenches would reduce the whole water table in a field and perhaps lead to a deeper side ditch to drain away excess water. It is often not necessary to lay these to falls, this depends upon local circumstances Such tiles are still available but have generally been replaced by short perforated round clayware pipes, which are still called 'tiles'. More recently long lengths of perforated and unperforated plastic pipes have been introduced. Often the tiles or pipes are sourrounded by some granular material such as a type of gravel called 'pea gravel' to slow the ingress of fine soil material which would eventually clog the pipe. But the soil for supporting the crops is then backfilled over the top, as they won't grow in gravel. OK so that is the agricultural use now for the engineering use. Saturated soil exerts a much higher pressure on retaining walls, foundations, basement walls and the like, than unsaturated soil. This is known as 'active pressure' in soil mechanics. This is clearly undesirable and has been the cause of many a structural failure. To avoid this pressure structures subject to earth pressure are protected by attempting to totally lower the water level to at or below the lowest structural level. In order to achieve this the backfill behind say a retaining wall or under a foundation is made from 'suitable material'. This suitable material is usually granular right the way down from the surface to the bottom, where a porous or perforated pipe collects and distributes water in the same way as the one in an agricultural field, but this results in a more drastic reduction in the water table level. This technique is also used to stabilise earth slopes (eg in the sides of cuttings) that might (would) become unstable with a higher water table. Hope this helps.

If the goal is to route water into the pipe and have it flow through the pipe to an outlet, then the perforations would be on top. If you are installing a French Drain, then the perforations are on the bottom. Holes on the bottom and gravel all around both work to ensure soil does not work its way into the pipe which will eventually cause the drain to fail. Water rising above the level of the gravel beneath the pipe will enter the pipe and flow away. If the water doesn't rise above the level of the gravel then it will drain into the soil. Water draining into the soil is just like the water that flows away through the pipe; that is, both are moving away and thus no longer constitute a water problem.

the “dressed state” approach Particle wave function has ground and excited states, with numbers of particles in each, and photon states have an occupation number. The photons and atoms can interact. https://www.quora.com/What-are-dressed-states-in-Quantum-Optics

An EM wave isn’t a component of a particle In my part of physics you can use the “dressed state” approach Particle wave function has ground and excited states, with numbers of particles in each, and photon states have an occupation number. The photons and atoms can interact. https://www.quora.com/What-are-dressed-states-in-Quantum-Optics

It's not, though, since iNow specifically said his references were "functionally equivalent". He made no attempt to argue against those references. You're free to argue that they aren't equivalent, but not that he's using fallacious logic. Again, it's not an ad-hom to make the claim that opinions and personal feelings might influence your judgement wrt your assertions. It's a fact. It's no judgement of your character as a human. It also doesn't suggest anything about your motives, only one of the pressures that may influence you. Now this is a strawman. Only your feelings (and the context they were in) were mentioned, the rest is a man of straw you knocked down as irrelevant. This is a false equivalence fallacy. Your style is more argumentative than conversational, a style I would employ if I wanted to win a debate by any means rather than learning from others in discussion.

I think the question can be approached on a number of levels. For starters, quantum mechanics makes time a very special parameter. You need a distinguished time that goes hand in hand with a so-called Hamiltonian of the system (the energy operator). This Hamiltonian is also the mathematical operation that embodies time translation for the system. GR, on the contrary, has no special time. There is no preferred coordinate system in GR. If you have no special time, you have no special Hamiltonian, which means you have no special time-updating law for the state. So right from the start, the symmetries of GR don't bode well with the special needs of QM. This difficulty though, can be overcome AFAIK. One formalism that does it is the so-called Ashtekar variables, that allow you to include all the constraints of GR into a significant set of variables that are amenable to quantization. And they give you a Hamiltonian. But a lot of preliminary work is needed to get there. In any case, as @studiot suggests, the conceptual bases are quite different. Then there is the question of the perturbative structure of the theory, as @MigL pointed out. The theory is non-linear, has more field variables, and the loop calculations become intractable pretty soon. This, in and of itself, would not be catastrophic, as Yang-Mills fields (in the non-Abelian case, which is strong nuclear force) are also self-interacting and have a richer field-variable structure. But YM fields are far better-behaved than gravitation at short-distance (large-momenta) scales. The theory is free at short distances (large momenta), while gravity is just the opposite. Gravity, also, has no polarity and is thermodynamically exceptional. This bad large-momentum behaviour connects with what today is considered the ultimate reason why gravity is so unwieldy to a quantum treatment: the dimensions of the gravitational coupling constant. It is dimensionful (and badly so), as opposed to the dimensionless character of QED, QCD, and EW coupling constants. Renormalization crudely consists in decreeing a maximum momentum Λ for every scale that we wish to study, and then prove that the observables inferred from the quantum scattering amplitudes can be expanded as a sum of two parts, one that remains under control (finite), plus a logarithmically divergent one (scale independent). Now, you cannot do that with gravity. There are two technical ways to characterize this in words: 1) Gravity doesn't look like a scale-independent quantum field theory at large momenta 2) The large-energy spectrum of gravity is black-hole dominated Equivalence of both is discussed at: https://arxiv.org/pdf/0709.3555.pdf It's quite technical, in spite of the title, but enough words can be found there so that a crude idea of what goes on can be obtained. There is a last-ditch attempt in QFT to make quantum gravity renormalizable, and that's called asymptotic safety, initiated by Steven Weinberg, and it's based on hoping for a point in the phase space where this bad behaviour is saved by a so-called fixed point of the beta function (a function that monitors the renormalization behaviour when you shift the cutoff). But it takes a lot of guesswork and I don't know what the state of the art is at this point. Then comes supersymmetry. It's a big hope, because supersymmetry leads to much cancellation of infinities. New technologies have been developed in recent years, like calculations using the formalism of maximally-helicity-violating scattering amplitudes. It's a technology that involves massless gauge bosons, always leads to finite calculations, but is considerably more abstract, because it uses expansions of the amplitudes that cannot be understood as local quantities (at a point), and it involves twistors, which entails expanding space-time points into pairs of massless spin-1/2 wavefunctions (Weyl spinors). Two interesting lectures on the subject. The 1st one is more technical, but again, enough worded arguments are given so that one can get an idea of what goes on. Quantum gravity and its discontents (by Stanley Deser, 2010): Quantizing gravity and why it is difficult (Leonard Susskind, 2013):

A perfectly cromulent view.

Hello all. Having a problem with 'tile' meaning a perforated pipe. But hey, it is English and am not the one to fix it 🥴 [ Image borrowed from the net.] Unsure of positioning the perforations under the pipe half for proper drainage. Seems like the gravel below the perforations level will always be flooded, (never flowing upwards to drain into the pipe) Shouldn't the pipe have no gravel under it, and perforations on sides ? What is the rationale ?

As far as I recall, there’s no particular name. In many cases, the region is all space.

That is a cliché that US Americans believe and which is unlikely to be true. Idea of free speech and related concepts are ancient and did not start with the USA. Moreover, the US had many, many issues with it. McCarthy, anyone? Not that the US under the last administration did not try that. Instead they muzzled the agency responsible for keeping folks safe. I am not saying that China did the right thing, but at least eventually they openly declared that the outbreak was an issue and did something (whether it was the right thing might be debatable). In the US meanwhile, the officials offered mixed messages and were not able to clearly communicate the severity of the disease. The differences in countries that did that and the US is clearly visible in the death counts (which is even worse when one also includes undercounted cases). In short, freedom of speech is an ideal that many American hold dear in principle. In effect, there are many mechanisms that undermine it, which tend to show up when the system becomes more authoritarian. This is basically also true for Europe, looking at some countries who recently have become more authoritarian (e.g. Hungary or Poland), some of the measures almost always include limitations of freedom of expression of some sort.

Makes sense, then. Thanks!

I think you and I have got to clear up the last point before it is worth discussing anything else. What you accuse me of is the polar opposite of what I have been saying to you throughout. - I have been saying that all scientific theories are mere models of aspects of nature. - I have been saying there are no axioms, just propositions, open to testing by observation. - I have been saying these so-called "laws" are made-made representations of aspects of the order we perceive in nature. I have, in effect, been saying there are no absolute truths in science whatsoever, and that everything is open to challenge. Yet, you seem determined to hear me saying what your own prejudices apparently assume I should say, while ignoring what I have actually been saying. Why?

And......my hovercraft is full of eels.

This is certainly NOT like gay marriage. Gay marriage doesn't infringe on any one else's rights. As JC has repeatedly pointed out, Trans athletes infringe on women's rights to fair competition. And there have been realistic examples given, Swansont; I posted one myself. INow and Zapatos are willing to put the rights of those 6 people ( the number of trans athletes, he claims ) above the rights of more than 50% of Earth's population. So, are we again telling women they are not even second best to men, but actually also behind trans people ? And Dimreepr seems to think that the only benefit from a 'game' is learning that others can compete with unfair advantages, so there is no point in actually playing.

Again. Elite female athletes cannot always compete equitably with 16 and 17 year old boys. The fastest female 100m runners in the World can be beat by some 16 year old boys. Unfair to cisgender women. No amount of testosterone will allow the fastest women athletes to compete with the fastest men. It's not just about testosterone. (or simply willingness to identify) This will be a failed experiment, hurting both cisgender females, and transgendered athletes who will likely be treated unfairly. Hopefully they will be treated as respectfully as possible...and the animus properly directed at the pseudo scientific idiocracy.

And so, most likely, is the air in between the dishwasher and the cupboard. The humid air mixes with the dry air, making it less humid. The water evaporates in the dry air. Water is going to condense on surfaces below the dew point, which the glasses probably aren't, or if the air is saturated with water. The latter condition is true in the dishwasher, but not outside of it.

Nonsense. I see tremendous beauty and feel an immeasurable sense of awe at the cosmos… and all without believing in silly human fairy tales and myths. Why do you keep posting such tripe? It’s not, though. If you’re not intentionally arguing against strawmen, then you’re showing your ignorance and lack of valid understanding of the perspective of others.

I certainly can't - and I doubt anyone else can since it seems, from the link I gave you earlier in the thread, to depend on what borate product you are using. The DOT product in the link is said to give a more or less ideal pH on its own. At least, that is how I interpret this passage: "When used in pools at typical dilution, the new formulation has an ideal pH of ≈7.6. Above pH 8, the chlorine becomes much less effective as a sanitizer, but below pH 7.4 the equilibrium trends toward hypochlorous acid and chlorine is lost more rapidly." So, as I say, I think the best bet is to check with the supplier's recommendations for whatever borate product you are using - or have in mind to use.

Cmon seriously, people saying at the start there are more than 2 genders? Wtf one has penis other vagina, and you can get surgery but still doesn't change how you were born. Also I think even scientists agree and swans agreed also that people born male are generally stronger than those born female so it makes it only fair with how the system of sport was made (category separation) that they are separated and transgenders compete in what female/male category they were born in. Or if the system was different and categories didn't exist we could just have a bunch of females coming last all the time. Dude it's called a thought experiment

All ball lightning/solid light sightings were the after effect of the retrocausal construction of Raven Illinois/Missouri, Phoenix lights were just balls the v-shaped spacecraft was unique to Illinois/Missouri in the y2k scare

It is a strawman argument because it does not attack the premises or reasoning of my case but of other cases, attack my argument not the arguments of others not arguments that I did not present. That's not correct, a counter argument that relies on my personal traits is an ad-hominem argument. Of course it refers to my motives, it said "they perhaps make you feel better psychologically" the motive for my argument is therefore to make myself feel better, even if that were true it does not serve to invalidate my argument, it is irrelevant. Consider what I said about identifying a flaw in a mathematical paper, it would be unacceptable to claim an analysis was flawed on the basis of some trait or motive presumably possessed by the writer. You would not say "You selected that integral because it perhaps makes you feel better" but one might say "That function cannot be used in that integration rule because of the imaginary exponent here" and so on. An argument is flawed if and only if either the reasoning is flawed or one or or more premises are wrong do you disagree with this? Yes you're correct, your criticism is accepted. My "style" (which is subjective anyway and could simply reflect your own biases) is irrelevant, stick to the premises and reasoning. Perhaps this may help, this is not something normally covered in science or mathematics degrees but is core in logic and philosophy, one needs to have a sound grasp of this if one is to engage in rigorous reasoning:

This is not correct. Referring to a presumed medium that has "instability" as "nothing" is an improper use of English. But lets move on, if you insist on this use of "nothing" so be it, I won't let that hold us up. Can there be a scientific theory for the origin of the "instability"? You may have heard of Sean Carroll a theoretical physicist and cosmologist? good, well here's a piece he wrote about this very subject, about Krauss's book. Here's an excerpt, this is his reaction to Krauss (whom he knows) (emphasis mine) Very well, if that's your opinion so be it. Do you mean all claimed truths are provisional (just to be a bit clearer)? because yes I agree, and of course anything can be challenged. So be it. But that isn't a counter argument, its just a belief, a proposition an unsupported unproven proposition. How can one adopt scientific rigor unless they first select their premises? (this is called being rigorous). I did not refer to unicorns, potatoes or Harry Potter, this is a strawman argument and how I might feel is irrelevant, please critique my argument not my presumed motives, let me show you a typical definition of ad-hominem: My feelings, race, skin color, sexual preferences, choice of diet, height, weight, taste in music, literature - have no relevance. If you disagreed with some mathematical analysis you were shown, perhaps a ten page paper of equations and derivations, would you need to refer to the author's "feelings" and "psychology" in order to pinpoint the error of reasoning? And you speak of "scientific rigor", the irony! The title of the thread contains the phrase "proves there is no God" and that is what I've been challenging. Oh dear oh dear oh dear, another ad-hominem is born...