MigL

I thought it funny. But, let's face it, you're no Eric Idle.

If you set up a situation where the rules of physics are violated, you cannot make predictions based on physics. QM guarantees that you cannot copy states perfectly, as you cannot know these states exactly. No copy can be exact, even if you have Star Trek's transporter with its Heisenberg compensator.

I agree with you imatfaal, and I don't put much faith in a changing G. However I'm not naïve enough to dismiss it outright, or ridicule the OP (not that anyone has ).

So if this is a 'two beaker' operation that the OP is using to reclaim an ounce of gold, he needs to implement a full scrubbing system ? Boy, I'd hate to think what kind of construction you guys get up to when you use muriatic to clean your concrete drive.

Definitely agree. But as we don't know the size and scope of the OP's operation, maybe not feasible or financially appropriate.

By stability I mean lack of internal pressures that tend to tear the country apart. But you're right, I'm confusing stability with 'getting things done'. And by 'getting things done', I don't necessarily mean favorable results, just unopposed decisions. Another example, North Korea. A country which can't feed itself. Yet can develop nuclear weapons and long range missiles, have a disproportionately large standing army, and terrify all her neighbours. All at the whim of its dictatorial dynasty.

I'd hate to see what the parliament ( hey, I'm Canadian ) would look like.

Has it ever occurred to you, Ricky12, that Brazil's population is increasing, and they need to be able to cultivate land to feed the people. Unfortunately that means clearing land of rain forests and jungles. We've done it in North America, Europe, and other parts of the world. And now that we are set, we want to tell other people that they cannot do the same, to achieve a level of agricultural sustainability and feed their people. Sounds pretty arrogant to me.

HaHa. Phi has to do the laundry. Do you also do the baking, Nancy ? Seriously, most guys I know don't have a clue about doing laundry. Unfortunately ( or ? ) I'm single, and my cats certainly won't do it...

I have a great idea for achieving world peace. But I'm not the smartest man on Earth and I'm having a difficult time synthesizing Dr. Manhattan's energy signature...

OMG, we've been spammed ! Can someone please clean up and take out the garbage. ( and maybe ban the jackass responsible for it ) Maybe we should be like Dr. Sheldon Cooper. If someone wants to join our 'group', they need to be able to answer a few science questions ( 5th grade level ) or pass an aptitude test.

I have to agree with you. Ronaldo is a bit of a 'queen'.

Both North and Scott have organic/acid acid cartridges for respirators. If an engineering solution rather than PPE is more desirable, then a scrubbing system that sucks away the vapours and passes them through a NaOH solution would be the way to go.

But G is a measured proportionality constant. It relates the force to the masses involved and the separation between them. It is certainly not a derived ( from first principles ) constant. I assume everyone is familiar with 'Newton's bucket', and the implications which Ernest Mach derived from the thought experiment. What if inertial mass is a result of the interaction with all the far-flung masses of the universe ? Then as the universe expands, mass moves out of the observable universe, which itself, becomes larger and larger, with the effect that mass is reduced and separation increased. This would decrease the strength of the interaction with a local test mass, i.e. its inertial mass would be reduced. And since we have no way of ( experimentally or theoretically ) separating inertial mass from gravitational mass, we must conclude that gravitational mass is also decreasing as the universe expands. Now we are certainly not going to assume that mass changes over time, so when we perform the experiment to relate the force of gravity to the masses involved and their separation, we measure the proportionality constant, or G, to be increasing over time. I post this just for discussion, as it makes for an interesting thought experiment ( and maybe what the OP was getting at ).

Your last paragraph is the key md65536, the problem is the differing frames. Yes to a third frame, the frame in a deep gravity well will experience time at a slower rate than a frame in perfectly flat space-time ( inertial and no gravity ), but they will all measure the passing of time as one sec per sec, in their own frame. In effect, the scales of time passage are different in each frame. In each frame they measure the age of the universe to be the same, 13.8 Byrs, but the seconds making up those 13.8 Byrs are not equivalent across frames. Say an astronaut became trapped by the gravity of a black hole 12.8 Byrs ago. He would then only have aged 1 Byrs since then, but he will still 'see' the rest of the universe having aged 12.8 Byrs, and so will measure the time to the origin ( big bang ) as 13.8 Byrs because of the different scale.

Consider the expanding universe, balloon analogy, md65536. Say it starts from an extremely small size and expands outward, like an inflating balloon, with the surface of the balloon representing the present. Now this balloon is going to be lumpy, as local space-time curvature determines the local expansion rate ( can I say passage of time ?). At any point on this balloon surface an observer can measure the time to the beginning as the radial distance from the centre. All of these radial distances are going to be different, i.e. no universal 'now', but since the local scale is also different from others, they are all going to measure 13.8 billion. This is the third different attempt at trying to explain myself. The previous two iterations confused things even more so I scrapped them. Hope this makes some sense.

Err, huh ? Just clearing your throat ? That's not the point I was making either. One could cover the world with solar collectors and have several hundred times more energy than we currently need. But the world would die. Solar collectors could be built in space to collect the 'wasted' energy which goes off to deep space, as our world subtends only a small angle of the Sun's circumference. Sorry if I didn't make myself more clear.

Remember though, that the Sun also heats and powers all natural processes of this world. Capturing all of it for our own use would leave none for natural processes.

Why do you think that " all observers agree on the age of the universe" implies a universal 'now' ? Take two rulers, one marked in centimeters and one marked in inches. You can be at the '10' mark on either, but that is not the same distance, because the scales are different. Clocks only tick at 1 sec per sec, in their own frames, all over the universe. And since there is no universal frame, there is no universal now.

If one considers that the city of Dresden was the target of about 4000 tons of incendiary bombs, and that the estimates for deaths from that one bombing, range from a low of 25000, to 100000 or a possible high of several hundred thousand ( not likely ) casualties, the two atomic bombs each killed from 4 times as many to about the same number of people. So what is different.. That they were Japanese ? That atomic weapons were used ? Are you suggesting that the Japanese didn't need to be stopped ? Or the Germans ? The figure of 175000 casualties from the atomic bombs pales in comparison to the number of Russians killed in WW2. War is hell. That's what makes it something to be avoided. Sometimes it can't be, Sensei.

If this is a "war is a terrible thing" thread, then I'm in agreement. If this is a "US is a terrible country" thread, then I've lost a little respect for you Sensei. P.S. Don't learn your history from Hollywood or Oliver Stone.

Sources of organo-phosphates are pesticides and nerve gas. I wouldn't recommend them as medicines and food

A wide beam laser is used to 'shave' thickness off the cornea for vision correction surgery. And it does no damage to the retina. I've had laser surgery for glaucoma, both burns around the edge of my iris and a hole burnt right through, in both eyes. The pin hole burn-through took less than a second. Both lasers are YAG, but I have no idea of the comparative power.

I think swansont's point was that Kinetic energy can be converted away to other forms. Momentum cannot. It is always conserved as momentum. @studio and strange... I don't recall impulse even being mentioned in the OP. Or are you guys just itching for a dust-up ?

Yeah, but who would want to let the French in ?