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Dig a little (a few grams) of the clay from the lake and weigh it. Shake it with distilled water + let it settle. Pour off that water and add some more distilled water and shake it up again and let it settle. Add a pH indicator and see what the pH is. Add acid until the pH indicator just changes, making a note of how much acid you add. Shake it again and let it settle. See if the pH has returned to the alkaline value. If it has then repeat this until you find out how much acid you need to add in order to neutralise the available alkalinity in the clay. From that you will be able to work out how much acid you will need to add to the lake. An alternative would be to do a "back titration". Take a known mass of clay and add a known excess of acid, then measure (by titration) how much acid is left. The difference is how much gets used up by the clay. It's worth remembering that rocks are not very soluble. Neutralising the alkalinity in the water will require neutralising the tiny fraction of the rock which is in solution but keeping the water neutral will require adding enough acid to react with all the alkali that is available from the sediments . That might be a lot.

The Open University (OU) lists over 900 free short courses in 8 categories. In the Science category you can look at Babylonian Mathematics, Chemical in drinking water, antibiotic resistance, Toys & engineering materials, working on your own in mathematics, telescopes and spectrographs to name but a few. Or you could learn/ brush up a new language in the language section Something to do in theses Covid times for all ?? https://www.open.edu/openlearn/free-courses/full-catalogue

What are you doing to reduce the subjective nature of many of your criteria? Surely "talent" isn't something we have the ability to objectively measure? Similarly, greed, violence, stability, and many of the others you mention depend on the person, so you need to remove as much subjectivity from your arguments as possible. Also, you talk about energies as if they are a thing instead of a property of a thing. Can I borrow a cup of energy? So you're applying a term that already has definitions in physics in a way that makes no sense. Are you eventually going to claim that talent creates gravity?

What they'll possibly try to do now is to lose that mess in a bigger mess that'll they'll try to create, going forward. Trash the political landscape with strategic lies and uncertainties to level the increasingly asymmetric situation they now face, and then convince people they are the way of this mess. Sound familiar? Then, pull out Project 2025 again as a solution.

Because, if DM really is composed of WIMPS, it does not interact with itself either. That means it does not contract to a galactic disk, because this is due to collisions of normal matter particles. For collisions you need some interaction. In the case of normal matter that would be EM mostly. X-posted with Mordred. Didn't realise he was still logged in.

OK, I'm not an astronomer either, so the little I have learned about Dark Matter also comes from magazine articles and the internet. I can summarise what I have learned as follows: - Dark Matter is a just a placeholder label, for something we can't yet explain, - the evidence for it is that the observed rotation rates of galaxies do not fit with the estimates of mass one gets by adding up the visible stars they contain, - there is something going on that seems to cause them to have extra gravitation, presumably extra mass, but which is invisible and transparent to EM radiation. - so the simplest explanation would seem to be that there are forms of matter out there which do not interact with EM radiation, but do exert gravitational attraction. (There are some further cosmological arguments to do with General Relativity and the cosmos but I have not followed those.) Is your understanding the same or different?

The air blowers will reduce the amount of natural carbonic acid, which is highly unstable in a turbulent environment. You might knock it down to the same pH as the catchment water if you turn off the blowers to find out. You only need to expose the lake surface to the atmosphere for it to oxygenate. The air blowers function is to temporarily disrupt the surface tension to allow gas exchange, it doesn't actually force air into the water directly. A bottom/up circulation should provide sufficient exchange without agitating the water too much, such that it liberates the carbonic acid as carbon dioxide. The carbonic acid is an integral part of the lake's natural pH management system. My reference is experience in dealing with persistently rising pH in hydroponic systems. Took me a long time to figure it out. Look into the carbonic acid cycle if you want to understand it more deeply. TLDR. Aim for water circulation from lower down to rise to the water's surface for gaseous exchange without agitation. I think the pump can be lifted some way off the lake bed, say mid-water, to avoid making the water cloudy and turbid from sediments. Plan your pump arrangement so that the water body moves around in a manner that covers the majority of the lake. The rain and wind will also contribute to breaking up the surface tension for gas exchange, so it doesn't have to be all artificially generated. You could try this as an experiment in a bath of the lake water and monitor the pH as you play around with it. To start, put some lake water in a mini-lake arrangement and leave it undisturbed, whilst monitoring the pH over time. It might take a few days. Then play around with your circulation pumps to find the best circulation pattern.

The transformation between the charts is explicitly given here, under the “Metric” section. This is not a Lorentz transformation. This is not the meaning of “isotropy”. You talk about synchronisation as if there was some meaningful notion of global simultaneity here. But there isn’t, because we’re in a curved spacetime. A clock stationary far away will never be synchronous with a clock in free fall towards the horizon, irrespective of coordinate choices. A Schwarzschild spacetime diagram is a diagram of Schwarzschild spacetime - unsurprisingly. You are free to choose your coordinates as you wish, but it still remains Schwarzschild spacetime. If you draw the diagram in GP coordinates, the cones both rotate and distort; if you draw it in SS coordinates, the cones just become narrower, but don’t rotate. That’s a consequence of how these coordinate charts work, but you’re always in the same spacetime. The locally measured speed of light is always c. It’s only the coordinate speed that will differ in (eg) Rindler coordinates - which is why I pointed out earlier that one must carefully distinguish between these. In curved spacetime, notions of space and time are purely local. Schwarzschild coordinates represent an observer who remains stationary far away from the central mass, and this coordinate system describes well the local physics associated with this observer. But the point is that they are only locally physical - if you try to use Schwarzschild coordinates to draw physical conclusions about distant frames (like eg a test particle in free fall), you’ll quickly run into problems. So I wouldn’t say they are unphysical, you just need to be very careful how you apply them in practice. In curved spacetimes, the difference between local and global is crucial. In particular, you can’t use Schwarzschild coordinate time to draw conclusions about what distant clocks record in their own frames; there’s simply no global notion of simultaneity here that can form a basis for this. —- Let’s return to your original claim that GP coordinates can’t be associated with a physically valid reference frame. I think we agree that the GP metric is a mathematically valid solution to the Einstein equations; if you disagree, it’s up to yourself to provide mathematical proof that it’s not. The question then is first and foremost what “reference frame” even means, mathematically speaking. The precise definition is given in (eg) Wu/Sachs, General Relativity for Mathematicians (1977), which is the one I’m using below: Suppose we are given a spacetime, being a semi-Riemannian manifold endowed with a metric and the Levi-Civita connection. An observer in that spacetime is then defined to be a future-oriented time-like curve that is everywhere smooth and differentiable. Finally, a reference frame is a vector field in that spacetime whose integral curves are observers. Straight away we notice that a reference frame isn’t the same as a coordinate chart. So what is a Gullstrand-Painlevé observer? It’s a free-fall geodesic of our spacetime (not necessarily purely radial) that connects an event far away to another event spatially closer to the central mass in a time-like manner, with the express boundary condition that at t=0 the observer be at rest. This geodesic gives our future-oriented time-like curve. So what is the vector field? It’s simply the 4-velocity field given by those very geodesics in spacetime. Recall that there’s no proper acceleration in free fall, thus (we’re in a curved spacetime, so covariant derivatives must be used): \[\frac{D^2x^{\mu}(\tau)}{d\tau^2}=0\] This system of equations, along with our boundary conditions, determines both the geodesic of our observer, and the associated 4-velocity field. But here’s the thing - we know that geodesics parallel-transport their own tangent vectors, and, since 4-velocity precisely is the tangent vector at every point of our motion, we are by the above equation already guaranteed that the geodesic is in fact an integral curve of its own 4-velocity field. This is hardly surprising! Thus, the GP observer (more precisely - his 4-velocity field) does indeed constitute a valid reference frame. If you still don’t agree, you need to show us explicitly and mathematically how a free-fall geodesic (which is what a GP observer is) is not in fact an integral curve of its own 4-velocity field.

why not in this we study about the brain and any study is science because science is learning

Psychology is far more than just therapy. As with the field of biology, biology being a word used to describe a broad range of specialist fields of biology such as marine biology, something a MD is hardly likely to have studied. Psychology is a word used to describe the study of human behaviour in a broad range of application, including cognitive thought process; making up psycho metric puzzles for application in a particular area; forensic psychology and the list goes on. In Australian Universities, psychology falls under the faculty of art. I'd have to research to ensure my accuracy, however, I am not sure of the complete list of academia under the faculty of art. I still stand by my original statement.

I explained already 2 times why I need this classification. I don’t need your help, I did by my own. As I reported already I think you want to steal an argument for publish articles to make your curriculum better. division of natural science are needed since exist different sciences

We are in the 21st century. Was no soil analysis performed prior to excavation? Never mind an EIA. Even now when the project seems to have gone tips up, the OP is trying to get free advice off the internet rather than employ the professional services that should have been on board before shovel touched dirt. The pH problem was foreseeable. It doesn't surprise me that this project is based in Thailand. It has a very familiar ring to it. I've seen many similar scenarios over the years here in Nigeria.

And there's no possible justification for that? Retired IT manager has a bash at terraforming tropical paradise. What could possibly go wrong?

I explain already. An easy example of illness for your species are the pollution, are possibile to make species of you to make "money for fun" to make a illness Yes I think that you stoled already from this forum with the cheat of make me think I'm stupid and I think you feel sad about this. I've searched information on the web, I hoped someone could help me to finish this classification. yes you'd better abandon ship

Studying this is a complete waster of time. The theory is that much of the universe is made up of "dark matter". What is more important is to see this as "time". It is a bit complicated and relies on an element of belief. But I am just trying to saving our scientists (and people on this planet), from wasting their time.

Mr Mr Mr. Take a leaf out of Salvador Dalí's Book. Leave Time at the decontamination shower. All I'm interested in, is w, x, y, z. Interestingly enough, I watched a Netflix documentary about Oragami, there was a quote on there that I liked. 'Each fold is a new memory'

And you must understand the basics of deduction and learn to read with comprehension.