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The detail to understand is that magnetic field ie the B field does not perform work it is the E field that does the work.

It’s not what I require, it’s what the description of Hawking radiation requires. I get the point Bye

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.

Yup, a quick internet search reveals pressure graphs with peaks between 30 and 75bar. Latter probably highly turbocharged marine diesels.

It would still happen regardless, the only difference is where. For very massive BHs you’d need to get far below the horizon before tidal forces become noticeable, whereas for small ones this might happen long before you even reach the horizon.

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.

@Mordred https://arxiv.org/abs/astro-ph/0310808 Page 13, equations 7, 8, 9.

It seems I was wrong about my previous observation. The OP is not a youngster, eager to learn, but rather a very immature person who thinks anyone who disagrees with his ramblings is deserving of a neg rep point. I guess it is less effort than making a valid argument. Tell me, Gioele, what new insights into nature does your classification system reveal ? This is not science ( which is what we try to do here ), and, if an attempt at philosophy, this is the worst kind based on the belief that the workings of the universe can be realized simply by thought in your own mind, with total disregard for observational evidence. If you learned some science you would know that the 'particles' that inhabit your atom environment, are a loosely defined concept until actually observed by an interaction. Prior to that, they are a mathematical construct of varying probability amplitudes, that could extend way outside what you consider their environment. The bonds that you say inhabit the environment of molecules, are actually the property of an energy deficit of atoms that does not allow them the possibility to escape; they are not a 'thing'. There are way too many misconceptions about science to list here. Please heed my previous suggestion to learn some actual science, and stop neg repping people who are trying to help you learn some. If, on the other hand, you'd rather continue in your blissful ignorance, keep neg repping people who try to correct your misunderstandings; I'm sure you won't be missed after you get banned.

Relax. No one here cares. All your cosmology eqns: (more than) three in fourteen had errors. I didn't provide maths of my own; just ordinary, correct maths. You naturally complained when I left you to fix some of your own errors. You ignored references I provided i.e. cosmology lectures and dimensional analysis. I even provided a worked dimensional analysis example in a second post. You complained I hadn't done enough to fix your equations and to this day you haven't mastered dimensional analysis (even the equation checking version), something which took me a fraction of a maths lesson when I was 14. It's very thoughtful, but you shouldn't just assume people want things. You've already given me a hundred references we'll both enjoy reading for the first time in our old age. Time to honour someone else. What are you on? An extreme case of projection. I've only sent you two references in recent years and you ignored both of them. "To put it bluntly not once have you ever provided any mathematics or reference paper showing any claim of [Mordred] being incorrect" It's rather sad but people rarely write papers claiming people with outlandish ideas are wrong. Whether it's claiming you can fly the Atlantic by flapping your arms really hard, or the earth will soon be under attack by deadly matter photons, you'll probably find some bean counter has refused to fund any research. Non sequitur You've been put to the question and given up any aspiration to be a pseudoscientist. Give it a rest. Maybe you should buy the book. It would be interesting to know what edition you used, and what went so horribly wrong.

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

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