exchemist

Nice idea but there’s no way to get this to work, unfortunately. The USA has to join the rest of the civilised world and get rid of the permissive gun culture, however hard and slow that is.

None. There is nothing you can apply externally that will do that.

The cream of the joke is Carlson was fired for objecting to Fox’s campaign of lies. But it couldn’t happen a nicer chap.🤣

Once you break the rules of physics you are in a fantasy world in which all bets are off.

@swansont is quite right of course: I wasn’t thinking. We need more information. What is the shape of the mirrors, what is the shape and dimensions of the 600sq m illuminated area and what is the angle of the beam to the ground? Is a diagram available?

I'm not quite sure what you want to know. Do you mean a formula for the rate of divergence of the beam? That's obvious, surely, if it grows from 51m² to 600m² , i.e. a factor of 11.6, over the course of 450m? Or do you want to know why it diverges at that rate? That would be more complicated - some function of the shape of the mirrors, I imagine.

Two questions: - On what grounds do you claim terrestrial forces could not have been responsible? - Have you calculated, or estimated, the magnitude of these interplanetary magnetic forces that you claim are implicated?

Central heating thermostat?

It’s a question of progressive pressure to change. We are moving quite a bit now: almost no senior politician any longer denies the need for action, and governments and industry are investing in the shift. Of course we have move faster but there won’t ever be a discrete tipping point.. People have get used to changes and find tangible upsides in it for them, especially when it impacts their personal lifestyles. We have not got far with that yet, apart from cars. Home heating is a big one.

I don’t think the Vatican, for all its faults, would want to have anything to with Trump. The guy seems to be actually evil.

I’m certainly with you 100% on maps. Like you I feel a need to know where I am going in relation to other places. I also like to have a mental picture of the journey. It makes me feel I am in charge rather than blindly following instructions.

On the contrary it seems to me that modern life requires mastery of an ever-expanding battery of computerised tasks, mostly to be done on your own without help. So mental agility is still needed but of a different sort. However I have certainly read of the importance of exercising the mind as one grows old. That’s one reason why I sing and why I do sudoku after lunch and wordle at teatime. And hang around science forums of course.

Yes it is only ex cathedra pronouncements on faith and morals. Most popes are very sparing indeed in their use of this. I think I recall this dodgy (and risky) doctrine was only formalised in the c.19th, at a time when the church was going through a phase of dogmatic absolutism.

Yes, pH can increase or decrease, or one can speak of a low (acid) or high (basic) pH.

Bed bugs are bloodsucking insects. If you’ve got those you need to fumigate the entire bedroom, paying attention to the underside of the bed and mattress as well as the top. But I doubt this is what you mean. If you mean dust mites, then washing should help. Woollens are washed not cold but at 30C usually. That should be OK. I would not go hotter if I were you.

I have a couple of questions: - How does your radiation concept account for the time dilation we observe in communications satellites, which is accurately predicted by relativity? - Are you an electrical engineer, by any chance?

Makes no sense. Vacuum fluctuations arise due to the uncertainty principle. Nothing to do with relativity.

That looks a lot better, certainly.

Yup. Chalk. CaCO3.

OK. By the way the anthocyanins in my red fruit turn blue just rinsed with water - before any detergent is added. So the water itself is sufficiently alkaline to do it. From looking it up, I see the pH of London water is in the range 8.0-8.5.

Yes I would definitely use deionised water and a fresh, untreated cabbage. But I've never done this myself, I should stress. My experience is only in the kitchen, where I find the juice from red fruits goes distinctly blue when I rinse dishes. Almost all of them get the purple colour from anthocyanins, I believe, from blackcurrants to aubergines and red cabbage, so the same behaviour is expected, modified only by whatever acidity there may be in the fruit or vegetable involved.) The reason for the colour change is quite interesting. These are conjugated ring systems with extensively delocalised π-orbitals. Protonation and deprotonation alters the bonding and thereby changes the energy gap between ground and first excited state, so that the molecule absorbs a different chunk of the visible spectrum.

These show different ranges in detail but in all cases the pH is 8 +/- 0.2or so. So red cabbage should be blueish, if there are no acids around to distort it. But as @John Cuthber points out, at such a neutral pH, very small changes in H+ concentration have have a big effect on the value, so any traces of acid contamination can alter it quite a bit.

Paul, when I cook red cabbage the problem is to stop it turning blue when I sweat it with butter or add any water (I live in a hard water area). The normal way to do this in cookery is by adding acid, e.g slices of apple, or vinegar. How did you prepare the indicator? Did you buy a fresh red cabbage and extract the anthocyanin yourself, or does it come from something in a jar. If the latter, it will almost certainly have some sort of acidifier in it, to keep the colour.

If it goes black when heated, you have some organic material present.

Daily Mail?