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Just to elaborate a bit more. When we speak of the invariance (not constancy!) of the speed of light, what this physically means is that the outcome of experiments is always the same in all inertial frames, ie uniform relative motion has no bearing on the outcome of experiments. This has nothing much to do with units or numerical values. Yes, it is always possible to describe the same physical situation in terms of different “geometries”, if you so will. You can eg forego any reference to curvature completely by choosing a different connection on your spacetime - the geometry is now curvature-flat, and instead contains all information about gravity in the form of torsion. But all this is saying is that one can draw different types of maps over the same territory, like having a topographical map vs a road map over the same region. That way you emphasise different information, but the actual experience of physically crossing that terrain is always the same, irrespective of what map you use to navigate. This is not revolutionary or mysterious, and reveals nothing new about the world. It’s “kind of trivial” as the poster in your screenshot correctly said. So I think if you put enough thought into it, it may perhaps be possible to come up with a mathematical description of spacetime in which c is explicitly a function of something. The reason why no one uses such a description is that any measurements of space and time obtained from this description won’t directly correspond to what clocks and rulers physically measure in the real world - you’d have to first map them into real-world measurements, which means additional work and complications without any discernible benefit. Irrespective of what description you use, the outcome of experiments will still be the same in all inertial frames, and this is what we actually observe in the real world.

I think the fact that this is being normalized is a huge issue in itself. Rather unfortunately flooding the zone really works in the age of short - SQUIRREL!

As iNow noted, they do. An AP story on this said they used secure communication, but I think that just means encrypted. The DoD has a secure network, meaning you have to have special credentials to gain access to it, and the devices attached to it are located in secure facilities. A reporter/editor would not have those credentials. They were flouting the procedures. Nothing accidental about this.

This forum is not a chain letter service.

They do have tools for this and special computers called high sides, but these DUI hires simply chose not to use them. https://apps.dtic.mil/sti/pdfs/AD1005160.pdf

AHOTUS works for me

I think microplastics wouldn't be my biggest worry. While I would agree that acute toxicity is likely not an issue, common materials such as PVC can leach plasticizers, such as phthalates. The immediate health impact is low, though accumulation over time is a worry here. I think typical water filters are certified to NSF 42 and 53 (and sometimes 401) which don't test for phthalates (I think). There are PVCs sold as fish or food safe, but not sure whether they are actually compliant to any standards.

As far as I'm aware, most of the uses to which we put ponds would preclude the use of plastics that leach significant amounts of toxic materials. (Who wants a fish pond that kills fish?) Of course, it may have become contaminated in storage.

There is also a broader issue that you do not want to have uncontrolled bacterial growth in your products. If it is not safeguarded against "safe" bacteria, they may also be vulnerable to harmful ones. And generally speaking, it is better to prevent issue rather than letting it run its course until someone is harmed. That is, unless the penalty is cheaper than safeguarding, which then would be a regulatory issue.

There are toxins that can leach from plastic which would not be filtered. And submicron nanoparticles do come off plastic, which at that size may get through filters. Finally, open ponds can also get windborne particulates and also coming down in rain - a recent study in Colorado croplands found microplastic both in fields and also being absorbed into plant tissues. These were not from some ground source where it was flowing into the fields - they were deposited from the air. So I would say that you combining both physical filters and also chemical detoxing is a good idea, but you may want to look into how your filters handle submicron particles.

Did you want an argument or a discussion ? 😀 Could not not stretch a filter fabric over the top of the sump, under the water ? As to the sump material. If it is bituminous I would avoid it, although in the past water tanks have been painted / lined internally with bituminous material, which is not in itself poisonous, in the past there is a risk of cancer from the bitumen.

Where does this "principle" come from? I have never heard of it before. It certainly sounds rather silly, on the face of it. But perhaps all it it is intended to mean is that, in a civilised society nobody has total freedom to act without consideration for others.

This is just as dumb and simplistic as the OP, you do understand that there's a minimal level of comprehension expected here? Or you'll be asked to leave... 😉

Freedom of expression? Ok. Why do you complain about the politics of Trump? One of the topics of this forum sounds like "Trump administration is crippling science". Crippling.. very dramatic. No, he is not crippling science, he expresses his views on science. Also, he expresses his views on the politics of the US. He is free to express himself, BECAUSE people voted for him. It was their free choice, they gave him this right-to express his views. You don't have the right to complain. I brought this example on the Olympic Opening Ceremony. Was the right of performers 'to express' themselves legal? I don't know why you say all the time that I'm trolling, when I am not. You have a very fat troll here, on this forum, he depreciates every comment he responses. But you are ok with him. I know, I am free to withdraw myself from participating on this forum. So, let it be.