MigL

This is one of the most interesting threads on AGW in a long time. It focuses on what can be done realistically and doesn't ignore problems associated with those actions. Solutions to the AGW problem should be based on maximizing effect of reducing/eliminating GHG emissions while minimizing problematic effects on people/society. In my province of Ontario, Canada, the biggest reduction in GHG emissions came from eliminating coal generation, and replacing it with natural gas. It would have been more expensive, but nuclear would have been an even better choice. It is my understanding that coal generation has dropped from about 50 % to about 30 % in the US over the last 20 years. A good first step would be eliminating coal generation altogether, and replacing it with natural gas, or even better, nuclear.

Did somebody say 'aether' ? ( gravitational, this time )

I' would agree. ( and disagree with Bufofrog ) In this scenario there is no force on the tote, as it is connected by a slack flex-hose, but the pump, which is accelerating the contents of the tote by exerting a force on the water in a specific direction, will feel an equal and opposite force in the other direction. Assuming the tote is open to atmosphere, only gravity and atm pressure are acting on the contents. Gravity can be disregarded, while atm pressure acts equally from all sides. If the pump was integral to the tote ( a solid connection ), the pump-tote system would experience a force in the opposite direction as the flow, but you specified a slack flex-hose.

But if you were going to do a field treatment of gravity, space-time geometry would be the field.

We could do with a little more civility around here. Both INow and Zap can call me names/insult me if they wish, and I won't take it personally; after a while you get to know people. New members however, haven't gotten to know our personalities yet, and can be put off by our behavior sometimes. I have come to recognize that you need to tread lightly in certain subjects like AGW, as some people will assume posts have ulterior motives/agendas; a new member, who is unsure about the science will ask a question and be accused of being a denier. Now, quite a few times this turns out to be true, but we've probably turned away quite a few new members who thought they could come to a science site and discuss anything science related, without being accused of having an agenda. I don't say "This is who we are; if you don't like it, there's the door.". Rather, I want to thank Wallflash for bringing it to our attention, and personally, I will endeavor to do better and be more civil. ( my avatar might look bad-ass, but I'm actually a very sweet guy )

and on re-reading my post and your reply, I realized I had Pythagoras backwards for positive and negative curvatures. Positive ( like a sphere ) should be MORE than 180 deg. Negative ( like a saddle ) should be LESS than 180 deg.

Energy providers don't choose the energy they provide. We, the consumers and industry, choose which energy we'll use, and the energy provider will provide it if they want to profit. BUT, we need to be given a choice first. Right now we don't have an alternative, especially if you don't live in a metropolitan area. I remember when gasoline was $0.69 per Imperial gallon ( I didn't drive yet in the late 60/early 70s, but I remember ). It is currently about $5 per imperial gallon, and people are still driving big trucks/SUVs if they can afford them. So who has changed their habits because of the added costs ? Certainly NOT rich/affluent people that don't need to. Yet people earning minimum wage, in smaller towns without good public transit are struggling to put food on the table, or gas up their car to get to work. Everything sounds simple and rosy if you ignore the downsides.

My ( limited ) understanding was that you could always tell using Pythagoras'... A triangle's vertices add to 180 deg in no curvature. To less than 180 deg in positive curvature. And to more than 180 in negative curvature. But that doesn't seem to apply to the FLAT Torus example I mentioned in a previous post. Maybe someone more familiar with diff geometry and topology can clarify.

Thanks for putting the 'meat on the bones' of our understanding, Mordred.

One thousand would be a single chip about the width of 20 human hairs. ( there are 5 in the 1/10 photo above ) An even bigger breakthrough would be a way to sequence the chips so as to have an array miles long. You could put the LHC out of business. ( kidding, the article doesn't mention power draw per 'cell' )

You want addresses for Rangerx and Raider5678 so you can go run them down ? I'm getting tired of the car/driving analogies myself. ( just joking, I don't have addresses...or do I ? )

That darn cat's wavefunction sure does get around, considering the cat is half dead...

I like ths... I would think that, since we are increasingly dependent on power, more nuclear ( and fusion research ) combined with solar panel 'farms to provide electric power for all applications ( improved battery tech ) would be a strong positive. Most of the programs pushed by Governments, such as cap and trade, or carbon tax, do little or nothing to reduce GHG emissions, as they just impose a 'cost' to continue doing business as always. Only those that can't afford it are forced to change their ways, so I see these initiatives as a strong negative.

Well it may help to consider that photons interact with the electrons in the medium they are traversing, and that leads to an 'effective' speed reduction. But actually, between each interaction, they still travel at c . Gravity is self-interacting, so one could assume massless gravitons travel at c also, except when they interact with themselves to reduce their effective speed. These would be the 'tails' Markus refers to

Yes, an unrolled cylinder is flat. As opposed to a hemisphere ( + curvature ), which lacks material near the edges to allow flattening ( the world map problem ) Or a saddle shape (- curvature ), which has too much material near the edges to allow flattening. And I remember reading the same in K Thorne's book, about the various ways to formulate GR. But I've never seriously considered space-time as something that can 'bend' or curve. However, manipulating the co-ordinates in that manner seems to fit extremely well with observation. ( by the way, what does "gasho" mean ? ) Wheuw ! I thought you were gonna say "There are many ways to skin a cat". Those are fighting words to us cat-owners .

You have never clarified the original question. You have allowed us to interpret the OP as we see it, and once we offer a solution to OUR interpretation, you tell us we are wrong ? How about reposting the original question, as YOU interpret it ( but in a clear manner, not like previously ), and then we can discuss it properly.

It's not a utopia; we have our problems. But we tend to work on the problems as one group. We don't have half the country pitted against the other, where certain unscrupulous people/political parties can leverage that polarization for their own gain. But Canada is a big country, and some regions undoubtedly get pitted against other ( see Quebec ). That being said, If I could no longer live in Canada, my second choice would be the US, and I imagine Rangerx feels the same. It is closest to 'our' way of life. Besides, I have faith in you guys, you've lost your way before, but always come back to the right path.

N Pelosi was had. M McConnel finally promised a hearing in the Senate that seemed reasonable, so she handed over the articles of Impeachment. At which point M McConnel reneged of the promise, and only wants to present arguments that the Impeachment process was a sham. IOW just repeating the process Congress just went through, and hoping ( guaranteeing actually ) a different outcome. Then they can claim D Trump was not Impeached, taking advantage of the fact that most of the American population doesn't realize that he IS Impeached already, and they can deny the whole thing at election time.

Read an interesting article today, that proposes Harry as the new Governor General of Canada. The current Governor General is Julie Payette, a Canadian ex-astronaut, who was apparently indicted in Maryland for assault and subsequently had the charges dropped and records expunged. Our PM called her the best of Canada when he nominated her. Apparently she doesn't like the position much, either. As the GG is supposed to be the Queen's representative in Canada, would Harry not make a much better choice since he'll be living in Canada ? He gets the GG security team, and he earns his keep. The only problem would again be the wife, as I don't think she'll put up with Ottawa weather ( preferring BC ), and she would balk at the ceremonial duties of the GG.

You guys make it sound like you actually expected things to unfold differently... For Americans ( well, not Rangerx ), you are very naïve.

For intrinsic curvature that is correct. An example of intrinsic curvature would be the old Atari 'Asteroids' game. The left side of the screen is identified with the right hand side, and the top with the bottom, such that when your spaceship disappears from one side of the screen it reappears on the other. The screen would be an example of a 'flat' 2dimensional torus, as opposed to the surface of a 'regular' torus which looks like a doughnut, and requires a 3rd dimension to visualize. Extrinsic curvature actually requires an external 'embedding' dimension. IOW a 4th dimension to describe 3dimensional curvature. An example of extrinsic curvature is the rubber sheet analogy of GR, and it is precisely why it is problematic. The flat 2dimensional sheet actually bends into an external ( 3rd, embedding ) dimension, when a mass is placed on it. I don't really consider the space-time of GR to be 'bendable' ( whatever that means ). But GR allows me to assign a co-ordinate system to that space-time, and the altered spacing of the co-ordinate gridlines in the presence of mass-energy ( or energy-momentum ) is the equivalent of 4dimensional 'curvature'. These co-ordinate gridlines are essentially equipotential field lines of the gravity field.

Way to go Mordred. You just gave him a whole bunch of 'fancy' words, whose meaning Conjurer has no clue of. He will no doubt use them as word salad in his next crap post. The rest of us thank you for your always informative posts .

If I have misunderstood the problem, I apologize And maybe the OP can restate it in a clearer fashion. Any fluid-dynamic effect can be considered as a pressure difference effect or a conservation of momentum effect. Does a wing produce lift because of the reduced pressure above the wing as compared to the pressure below, or does it produce lift by accelerating the air mass downwards such that momentum conservation imparts an upward acceleration to the wing ? Same with the propeller example previously used. Does the propeller reduce pressure ahead of it or does it accelerate a mass of air rearwards ? Similarly, a rocket can be considered by either the pressure imbalance method, or, momentum conservation method. ( most physicist prefer the momentum method as it seems more 'formal' )

Maybe you should have waited till after the 'flash' was seen to post this. Until then, it's just wishful thinking on your part. ALL information is constrained to travel with an upper limit of c .

And you'd be wrong. AGAIN !