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Comment Re:Idiot (Score 5, Informative) 366

Melting aluminium is an *ideal* use for unreliable power: the primary cells can run at variable rates or even in reverse to stabilize the grid, or some of the molten product can be staged for running optimized Al air batteries. Germany is already doing this,

From that link, other energy-intensive processes may be suitable, "including those used to manufacture cement, paper, and chemicals. Making chlorine, used to produce paper, plastic, fabric, paint, drugs, and antiseptics, also requires electrolysis."

Comment Re:It's always been this way. . . (Score 1) 197

And tiny black slots on the side of black cases. I keep a flashlight next to the laptop so I can find them.
And blue on gray text on websites.

I use glasses half the needed strength so monitor and distance are equally blurry (I take off the glasses for close work and reading).
Windows 10, 1920x1080 with 150% increase in icons and text, at two meters to a 46 incher, works for me :)

Comment Re:Important distinction: Obervable vs watching... (Score 1) 168

Even abstracting away the surrounding environment, doesn't the cat qualify as a observer of its own death?

How about if you take the place of the cat and securely lock the box so on one can open it - do you become immortal?

But as you say, idealized imaginary constructs rarely model reality.

Comment Re:Important distinction: Obervable vs watching... (Score 1) 168

Exactly, and the same point removes the paradox from Schroedinger's cat. "We" don't have to open the box to force the cat into one state or another, it's the radioactive decay that observes the cat death. We simply find out whether it has happened or not when we open the box.

But this could be a useful phenomenon, using a light beam to switch tunneling on and off.

Comment Re:Photons and solar wind (Score 1) 163

That's a bit misleading, although technically correct in the center of momentum frame. In general the relativistic energy is obtained from the length of the 4-momentum m(vx, vy, vz, mc^2) which gives the oft-quoted E=mc^2 for a mass that has no motion relative to the observer. But for a massless particle (which according to the theory must move at the speed of light in every frame), E=Pc .

So more accurately the Sun loses mass to produce light but the transfer to Earth involves only energy and momentum. Absorption by the Earth increases the velocity of bits of matter which results in a corresponding mass increase.

Comment Re:faster than light never violates Relativity (Score 1) 226

Yes, the direction of the time axis is as observer-dependent as is the rotation of spatial axes. In Cartesian geometry the distance (dx, dy, dz) between points depends on the choice of coordinate system, but the length of that 3-vector is always the same (compared to the distance between some reference pair of points)

Similarly in space-time it is only the length of the 4-vector between events A and B that can have any physical meaning. This length can be positive, negative, or zero. A positive length means the events are outside each other's light cones ("space-like"), thus have no causal influence on each other. A negative length ("time-like") means each could have participated in the events leading up to the other.

A zero-length ("light-like") means there is no event separation between the two, i.e. they are the SAME EVENT (this might be understood as length contraction in the direction of motion going to zero when v=c). All the points on A's light cone (which includes B) are the same event as A. All the points on B's light cone (which includes A) are the same event as B. So far there is nothing to determine the direction of time, and indeed the physics describing the transfer of action when v=c is symmetric with time.

But there are points Z on A's cone not on B's cone and these are also part of the same event AB even if they also have space- or time-like separation from B. Even if nothing can interrupt the ZAB event, the direct ZB distance could be time-like and thus set a direction of time, B before A. If B was a causal factor for A, it is difficult to see how ZAB could not be affected by the the direct BA interaction. It seems to me, here is the collapsing wavefunction. The only way I can reconcile it, is to introduce some time average long enough to allow all these paths to interact.

Comment Re:Plot Hole (Score 1) 179

At the crucial moment Frodo could not destroy the ring! The long trek was needed to bring about the fight in which Gollum reclaims the ring and then, in his exhaustion, falls with it into the crevasse.

Also Sauron was distracted by all the fighting and uncertainty caused by the rumors of the ring being carried around.

Comment Re:Straight to the pointless debate (Score 1) 136

NASA did destroy a large amount of imagery in the 1980s, despite a public outcry I certainly contributed to. The official line was that no one knew how to read the warehouses full of 7 track tapes to for conversion to CD (the 2400 foot tape could store 5 to 140 MB depending on density). The obvious reason was no one wanted to spend the money to replace all the classified pixels with innocuous ones. And so mankind lost a large amount of wealth.

Comment Units were chosen for the conclusion? (Score 1) 409

Can't be bothered to read TFA, and got a life-threatening yawn scanning the overly complicated rebuttal.

Dollars of carbon offsets vs. megawatts of installed capacity is mostly a measure of the average capacity factor during operation, possibly adjusted by the fossil fuels needed for maintenance but that is way beyond this level of analysis.

Capacity factor is something like 20% for solar (5 full sun hours most days), 40% for wind in a favorable location, 95% for nuclear until something bad happens In the end if they all have the same cost per installed MW then nuclear wins. If solar had 5x less installed cost then it wins, similarly for wind at 2.5 less.

Comment Re:Engineering win (Score 1) 262

But no net energy that way, just pointless multiplication of PV panels. If you want a energy return equal to the energy that went into making the first panel, the first 5 years is a loss - all it does is produce a panel. If you produce no more panels after that it takes another 5 years to recover the energy you could have used 10 years earlier to do something useful. Only after that is net energy. Some of the net energy can be used as a new source of useful energy, the rest to produce more panels and ultimately as the energy source to develop a Dyson sphere. When you stop building panels, it's all net energy.

Comment Re:Engineering win (Score 1) 262

Energy Return on Energy Invested (EROEI) of PV can be 3-4 in favorable cases but the rate of return is also important if you want to multiply the resource. If energy parity for the first panel takes 5 years then its output could produce a second panel in another 5 years. So for 10 years you get no net energy, after which you can tap some of the output for other uses while still continuing to add panels at an accelerating rate. Doesn't matter if you start with 10 or 10 billion, there is still no net energy for 10 years. Starting with a large number could cause energy shortages and social unrest which could end the sustainable growth entirely.

Yes, we should have started 20 years ago.

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