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Comment: The trick is to remove the context... (Score 1) 406

by rgbatduke (#49159359) Attached to: Is That Dress White and Gold Or Blue and Black?

What color the dress is is impossible to tell from a photograph for countless reasons. What color the pixels in the photograph are is beyond question. They are light blue. One can simply box everything but a small patch of color from the dress and out of any context at all it is not white. If one has any real doubt, one can always go into the image itself and look at the RGB of the image.

The dress itself could be white, could be blue, could be grey -- and reflecting light from some blue source (like the sky, like a blue wall in the background behind the photographer). One would have to be there to know, since there are no other foreground objects to use to normalize our beliefs. But the pixels -- the pixels are what they are, and it ain't white or any of the nearly balanced fifty shades of grey.


Comment: Interesting... (Score 1) 139

by rgbatduke (#49138945) Attached to: 12-Billion-Solar-Mass Black Hole Discovered

So if there is one, either there is a substantial asymmetry or there should be many, following a reasonable distribution curve. If there were many, uniformly distributed, then there should be at least some well inside of the 13 gigaLY sphere (where this one is on the periphery). If there are some inside of this sphere, obviously they stopped "munching stars" and being bright at some point, probably some point before 13 billion years ago. Therefore we can conclude that either:

a) There are an unknown number of dark galaxies (to coin a term for them) wandering around inside of the 13 GLY sphere -- black holes with essentially galactic mass but with no remaining light matter to "munch" nearby and thereby light them up; or

b) This represents a substantial asymmetry in the distribution of early matter, one that is not replicated inside of the visible ~14 GLY sphere;

c) Something happens to galactic black holes after they've munched all of the stars. New physics. Space aliens. The fall out of our cosmos and into another.

Possibility a) sounds like a possible source of "missing matter" -- dark matter inside the visible Cosmos, wandering around in between the visible galaxies and possibly even more prevalent. It doesn't seem as though it would work as well for dark matter inside of galaxies themselves, unless this phenomenon scales out so that there is a distribution of black holes of sizes ranging from supernova remnants produced much later through 10s, 100s, 1000s, 10000s, 10000s, ... 10^9s or more stellar masses. If 1% of the stellar mass or better objects in a given galaxy were black holes with a mass of 100 to 1000 stellar masses with no leftover supernova remnant gases infalling to light them up, that's a whole lot of "dark matter" right there.


Comment: Re:Fuck it - everyone for themselves. (Score 1) 364

by rgbatduke (#49138159) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt

Well, the mismatch depends on where you are. Where I live, with a SW facing rooftop, peak demand is mid-afternoon mid-summer when insolation maximally heats my house and the AC runs all the time. Roof panels could conceivably support the AC load while at the same time form a third layer of matter with a ventilated air gap right above my actual roof. This would suck ambient air at around (say) 30 to 40 C in and pull it up in between the solar cells themselves (which would heat up as well as generate from direct sun) and radiate LWIR both ways. I estimate that this extra layer would reduce the difference between my physical roof shingles and ambient air by 2/3. Since I then have R-40 or thereabouts in the attice ceiling, a finished attic we don't use much in the summer, and an R-20 insulated floor between the attic and the house, I expect that it would reduce the load on the attic AC pretty substantially while generating enough electricity to easily keep the house cool to even cold all afternoon (plus running any appliances etc).

Storage would be nice, but in NC I'd be able to just pump surplus back into the grid and make the meter run backwards, "storing" the energy by reselling it to my neighbors and getting it back for free later in the evening. Which brings us back to TFA -- I personally think that communities should force power utilities to permit this resale, subject to a) validation of the equipment, mandatory inspection, etc. Private equipment should not be permitted to mess up the public grid; b) a clear statement of liability and requirement of insurance (the power company isn't responsible if your equipment fails and messes up either the local grid or the local grid connection via (say) lightning messes up your local equipment); and c) personally I think a reasonable surcharge/tax for the use of the public uitilities lines and distribution network to resell your power to your neighbors is pretty reasonable.

With that said, there is a lot of room for negotiation as to just how such a surcharge should be billed. Arizona's $0.70/month/KW is perhaps the dumbest and least equitable as it gets billed even if you don't push back any power, or if you use most of the power yourself and push back comparatively little (on average). A much fairer scheme might charge you rate A for energy delivered through your meter, and pay you rate B when you deliver energy back through your meter. In the specific case of Arizona, where they charge a comparatively little $0.11/kwh, they might consider paying you back $0.105/kwh, or $0.10/kwh. That way in a dark and stormy month when you generate little power and use all you generate yourself, you don't get dinged $7.00 just for being connected, but in a bright and sunny month when you sell back 20 kwh/day but also use 20 kwh/night, you basically pay $3.00 to $6.00 for the electricity you the otherwise "break even" month. I'd advocate the 5% rate, of course, and the power company would prefer the 10% rate, but the point is that this formula is a lot fairer than a flat rate.

It also makes sense in terms of amortization. If you buy yourself a good sized battery pack to run your house at night, it is going to cost you thousands of dollars. Call it $1000. Amortize it over 10 years, you have to pay back $100/year. Borrow the money, pay it back like a mortgage, you'll end up paying somewhere in the ballpark of $150 to $200/year. Hell, call it $120 -- $10/month. So even if it costs you only $1000 for a battery pack capable of running your house off of the grid all of the time, even if the lifetime of that battery is at least ten years (neither likely to be true, so far), even if the battery pack requires zero maintenance etc, the power company fee of $7/month to "store" your energy is cheaper to you than the cost of the money required to store it yourself.

This could change if somebody ever invents a cost-effective no memory high energy density battery with a lifetime of 10,000 full cycles (call it 30 years of daily deep cycle). And there are a lot of people working on this. But if/when it becomes cost effective at the consumer level, it will already have been or become more cost-effective at the utility level by around a factor of two, and utilities will simply start adding large battery packs to their burgeoning panel farms and start significantly reducing fuel based generation of the so-called "base load".

I see a real struggle between public utilities that cannot remain in business and maintain their lines and so on without a substantial and ultimately irreducible demand and rooftop solar with batteries -- going almost completely off of the grid -- that threaten to reduce demand below that irreducible level -- in around 10 years, with the next factor of two reduction in the cost per watt of consumer installed solar. Or, of course, Lockheed-Martin may have commercial fusion by then and everything will change and PV solar will pretty much evaporate, cut off at the legs by energy provided by what amounts to "free fuel", but without all of the hassle of intermittent supply or storage.

What I don't see is any future where coal continues to be a dominant source of electrical power for over 30 more years no matter what we do now. We could completely ignore CO_2 and build all the coal plants the world needs to provide the energy required to lift the poorest 1/3 of the world's population out of 17th or 18th century poverty, just as China and India are doing and will continue to do and be damned to AGW, and it will still become cost-ineffective to build more of those plants, without the slightest tax incentives or penalties or encouragement, within the next 15 years even without fusion, within the next 10 years with fusion. Indeed if fusion is realized, it won't take 30 years -- more like 15 to 20 and coal burning plants will be replacing their coal furnaces with fusion cores in place. RCP 6.5 is probably already overly pessimistic, and with a total climate sensitivity of around 1.8 C (my own best fit to the data) we will warm roughly one more whole degree C, maybe, before CO_2 forcing stabilizes.

What the climate will do then is still anybody's guess, because we cannot predict climate and do not understand climate and the climate is perfectly capable of starting an ice age with CO_2 several (as many as 10 to 20) times as high as it currently is (it has done so in the past, in the Ordovician-Silurian transition). The system almost certainly has chaotic nonlinear negative feedbacks as extreme as a warming induced by semi-permanent shifting of the Gulf Stream 500 miles to the south, putting the entire North Atlantic and Arctic into the icebox (while heating the tropics and maybe even overall warming the globe!) and triggering the next glacial episode. Or not. Unpredictable is unpredictable.


Comment: Re:Fuck it - everyone for themselves. (Score 2) 364

by rgbatduke (#49132915) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt

$7/month for a 10 KW service has to be compared to $0.11/kw-hr for Arizona electricity, scaled out to the actual energy consumed by the household. If I am paying $150/month for electricity and drop that to zero, netting $143 doesn't increase the amortization schedule for the hardware by an enormous amount. Is it reasonable? Hard to say. Charging the consumer SOMETHING for the use of the lines isn't crazy. I pay $15/month just to have power turned on to a cabin I hardly ever use and that consumes no electricity at all. But it is cheaper than having the power turned on and off when I do use it.


Comment: Re:Fuck it - everyone for themselves. (Score 2) 364

by rgbatduke (#49132525) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt

FWIW, I agree with you completely, sir, and I don't even "believe" that AGW is likely to be catastrophic or that CO_2 is intrinsically bad (I actually have pretty good reasons for my beliefs, but not worth the flame wars asserting them entail). Solar power SHOULD come into its own when it is cost effective. Indeed, it is the capitalist way. In the case of power, though, since power companies are hardly capitalist enterprises -- they are publicly sanctioned local monopolies and nearly completely protected from anything like actual competition -- it is entirely within the rights of the same commonwealth that gave them the monopoly to require them to run the damn meter backwards for people that put energy back into the system by whatever means. It is POSSIBLY OK for them to add in a "tax" of some sort and pay back the added power at a SMALL discount, since the consumer is using company resources to effectively redistribute their energy surplus on lines maintained by the company. But then, they are also helping the company load balance and avoid building new generation facilities, so it isn't even clear that should be the case.

I myself already have replaced my windows, my roof, added in a double layer of high-R insulation in the attic, replaced all of the old furnaces and AC units with uber-high-efficiency units and use tankless gas hot water (which leaves a bit to be desired, actually). My energy costs are so low there isn't a lot leftover to pay off an investment in solar out of reduced cost of purchased electricity (one of the paradoxes of this is that your amortization scheme depends on how much you pay out, and conservation measures elsewhere actually increase amortization to where the advantage of PV solar once again is marginal to lose-a-little).

Still, I expect to PROBABLY bite the bullet and do rooftop solar in the next 2-4 years, sooner if hardware gets cheaper faster (reducing the amortization schedule). For the electric utilities, though, solar is already a no brainer win and they are building their own solar farms just because if I can break even or win a bit at full retail costs for solar, they can probably double my payback via economy of scale in solar farms. That may be why they are opposing the buyback option -- they can make more money making solar on their own than reselling solar energy you made and sold back to them at cost. In fact, they don't MAKE any money on the latter.


Comment: Re:Right... what could go wrong? (Score 1) 421

by rgbatduke (#49116809) Attached to: What If We Lost the Sky?

Obviously not. My physics Ph.D. is just an accident.

It is equally interesting that you completely avoid the point I was making, which is that we cannot successfully predict the climate using general circulation models. But I suppose if you know any physics or mathematics you already know this. You certainly know how to argue on the basis of logical fallacies. My statement that we are not able to predict the extent of any warming caused by CO_2 and are very, very far from being able to show that it is or will be a bad thing does not, in fact, equate to stating that there is no such thing as the greenhouse effect or that increasing CO_2 should not cause a logarithmic increase in average surface temperature. Outside of that, it is a simple matter of fact that -- if you bother to actually look at e.g. figure 9.8a of AR5 -- the GCMs do an absolutely terrible job of either predicting or hindcasting the climate outside of the reference period where they were dynamically tuned to match it.

Some other facts. One cannot observationally separate natural versus forced warming in a dynamical nonlinear chaotic open system like the Earth. The error bars in our knowledge of past climate state are far larger than are acknowledged to the public (when error bars are published at all -- as a general rule a simple line graph is drawn as if it is "true") and IMO the error bars on things like HadCRUT4 -- which are only a factor of 2 larger in 1850 than they are in 2014 -- are completely absurd. And the GCMs, BTW, are basically just dressed up weather models, run forward in time on an absurdly coarse (compared to the Kolmogorov scale) spatiotemporal grid, some 36 orders of magnitude short of where they would need to be to be able to semi-reliably actually integrate out the models from known initial conditions, if we knew the initial conditions. They are limited not by design (only) but by the simple fact that we cannot afford to build a computer network capable of solving the problem.

But hey, I probably don't know anything about mathematics or statistics or computational modeling or large scale computation either. So feel free to dismiss my opinion because you don't agree with it on the basis of my presumed incompetence. After all, anybody that doesn't agree with you must be ignorant or stupid or being paid off or holding a vested interest or -- pick your favorite fallacy and have at it.

In the meantime, by all means support research into ways to irreversibly change the climate system even more than it may or may not have been changed already. What can go wrong?


Comment: Re:About right (Score 1) 241

by rgbatduke (#49115323) Attached to: In Florida, Secrecy Around Stingray Leads To Plea Bargain For a Robber


I think it would have a substantial ripple effect. TFA isn't about possession, it is about using a "lethal weapon" in a drug-related crime. If you subtract out the pot, you also take away the right to search people who happen to visibly be smoking pot and your odds of catching them for secondary offenses go way down. Sadly we wouldn't make a dent in the petty crime committed to support a drug addiction (as pot is not addictive and not so expensive most people feel compelled to steal in order to afford it) but it is a good first step in that direction as well.

And even 20% fewer lawyers is a good thing. With luck we might even make it 25 or 30% fewer. So far I've spent $20K or very near that defending my sons from silly possession charges, almost all of it going to lawyers.


Comment: Re:Light Pollution (Score 1) 421

by rgbatduke (#49114047) Attached to: What If We Lost the Sky?

We've had traffic signal LEDs for a while, but AFAIK no overhead street lights. I'm not sure they are bright enough to meet their "standard" or whatever.

I'm just quoting over the counter prices I see in my grocery store or local hardware store. So far Duke power hasn't offered any killer deals on them (although they do periodically with CFs, but I'm already using CFs throughout the house). Also, I need/want 100W equivalent brightness and the best Harris-Teeter can do is 60W equivalent for around $25-30. Online Cree bulbs (Cree is right down the road and some of my ex-students work there) are around $24 for 100 W equivalent, Eco-bulbs around $23, save a bit if you buy in bulk.

That's a lot of money for a single bulb. Yes, they claim 25,000 hours. Yes, the bulbs haven't existed for any reasonable fraction of that much time so we have no idea how long they'll last. My garage has a whole bag of CFs that are rated for 8000 hours and didn't make it to 3000.


Comment: Re:Light Pollution (Score 1) 421

by rgbatduke (#49111701) Attached to: What If We Lost the Sky?

Where do you live? Someplace either very enlightened or broke, I imagine. Mostly enlightened if they are buying LED lamps, which are not cheap.

But hey, when I visit Charlottesville, it has these lovely 1 meter wide bike lanes on most of the streets near UVA. I'm so jealous. Durham just painted a line on the side of existing streets that sequesters anywhere from 0 to 40 or 50 cm and call that a "bike lane". On my own ride into campus there is a place where it goes from 40 cm to 0 cm under an overpass at one of the two busiest traffic points on the entire route. Several people are badly injured or killed every year riding bikes in Durham (including, a couple of years ago, Seth Vidal, the principle developer of YUM and a good friend of mine) -- I wonder why?

These are the steps we should take long before we try uber-expensive and risky measures like mucking around with either atmospheric chemistry or space blankets in the sky or even massive (and hence expensive) rail projects. They make sense even if AGW is nonsense or sensible but not a real threat or even beneficial. It's a lot healthier for me to ride a bike into work -- or would be if it weren't for the substantial risk of injury along the route and the fact that I'd have to ride down a mile of country road with an inadequate bike lane during rush hour in the dark because of the silly time shift. Bike lanes, losing most of the street lights and regulating commercial light pollution after hours, and some clever use of electronics to control crime instead of light. They make sense even if Lockheed-Martin does have commercial fusion (as they claim that they will) within five years.


Comment: Re:About right (Score 3, Insightful) 241

by rgbatduke (#49111539) Attached to: In Florida, Secrecy Around Stingray Leads To Plea Bargain For a Robber

What's the point of putting anyone in prison for weed ever? If the states would just get around to legalizing it completely, no more BB-gun crime in your area! Prisons would empty! Lawyers would starve! All of these are good things.

And one day we will. As my son points out, every year, lots of Old People (tm) die. At some point enough of them who learned about the evils of pot from William Randolph Hearst and Anslinger via vehicles like "Reefer Madness" will have died, and the simple fact that states that have legalized it de facto or de jure aren't imploding in an orgy of drug-fuelled crime will be persuasive even to those that think that it is not necessarily good for you to smoke pot. And on that day, every single person who lost their freedom, their health, their wealth, and their future not because of the chemical effects of pot but because we made it illegal and created a world where breaking any law, just or not, is dangerous will cry out to the sky:


Comment: Re:Light Pollution (Score 3, Insightful) 421

by rgbatduke (#49111347) Attached to: What If We Lost the Sky?

Yeah, and did you notice that nobody -- nobody at all -- is calling for street lights to be turned off for good. Everybody's worried about burning coal, wasting energy, making resistance heating electric hot water heaters illegal as of this year (sheesh!). They want us to turn off the lights in our houses, they want us to spend $20-30 on LED bulbs because incandescents use too much energy -- but the streets are lit outside of my door with enormous halogen bulbs that burn all night even when there are no human eyes open to see their light. Empty parking lots blaze with halogen and mercury and neon. Cities string Christmas lights by the thousands along miles of road once a year. We pay for all of it, and yeah, it means that we can't see the sky particularly well even living on the rural edge of the city with deer in our back yard.

As a species, we're scared of the dark. We don't even consider turning off all of this completely wasted light (and saving some serious power, instantly) because then bad things would come out from under the bed and get us.

We're not even completely incorrect in this belief. One of the bad things is us and we are indeed scary as shit.

However, for far, far less than it would cost to loft crap into upper atmosphere or orbit, for far less than it would cost to even "commission research into" eventually lofting crap into orbit, we could start to actually use smart technology we already have and e.g. make street lights motion sensitive, or control crime (the usual excuse for having them, since "to prevent irrational fear of monsters" isn't an easy political sell for all of its truth) by actual robocop monitoring, looking for crime and not just putting up lights to nominally scare it off.

One could go down a rather long list of petty vanities that cost comparatively huge amounts of energy that we routinely pay for -- and waste. Billboards. Streetlights. The pointless annual time shift. Trucks vs trains. The utter lack of functional, safe, bicycle lanes in almost all the communities in the US. Electric cars. Living in borderline desert regions instead of water-rich temperate regions just because cheap, plentiful energy and long range importation of water makes it possible if unwise (as California and Las Vegas and the southwest in general may learn any year now).

Personally, I think that the evidence for catastrophic anthropogenic climate change is all but nonexistent -- it is a simple matter of fact that the changes in climate from the mid-1600's to the present, whatever their cause, have been almost entirely beneficial and in any event are utterly lost in the noise of normal daily and annual variation (overall warming from that entire period is around 1 C, an a signal too small for people to even notice against the noise). If someone truly "believes" in it, however, in spite of the fact that the models that predict it suck and the IPCC itself in the third annual report admitted that the problem of predicting the climate was basically unsolvable so that it is no surprise that the models suck -- let's start by turning off not the lights in my house, where I live and use the light, but outside where all it does is help the deer find the best hastas and roses from my garden to eat late at night.


Comment: Right... what could go wrong? (Score 4, Interesting) 421

by rgbatduke (#49111083) Attached to: What If We Lost the Sky?

Seriously. We have a perfect understanding of the climate. We can predict to a tenth of a degree what the weather will be two weeks or two hundred years from now anywhere on Earth. We fully understand what triggers ice ages and can hindcast the climate of the entire Pliestocene, quantitatively. Our knowledge of solar dynamics is almost perfect, so we can confidently predict the state of the sun well into the future. Our measurements of atmosphere, ocean, and land are complete so that we know the entire state of the ocean (for example) well enough to predict with complete accuracy its future evolution given any possible variation of solar input. Finally, we are perfectly capable of predicting the future course of human affairs -- global population, the distribution of that population, land use -- and can predict already precisely when we will make critical scientific and technological breakthroughs (like thermonuclear fusion or widespread LFTR fission or storage batteries that don't suck or high temperature high current superconductors) . Our knowledge of the interior of the Earth itself is at last nearly complete, so we can predict to the day when Yellowstone or other supervolcanoes will wake up and erupt continuously for ten or twenty thousand years. Finally, once we create an orbital cloud of atomic sodium (or whatever) into space, it will be easy to remove it or rearrange it if it turns out to do something completely different than we expect, such as trigger snowball earth or act in its own right like a layer of greenhouse gas between the Earth and 3 K infinity.

Oh, wait, those are all things we don't have, and can't do, and don't know. And I absolutely shudder to think of the price tag, both in dollars and in joules.

I swear, common sense is a lost art.

Let's go back to discussing orbital solar cells as a solution to both energy production and screening. Adding 64 MJ/kg (times a thousand or so) to the cost of solar cells by lofting them into orbit and giving world governments potential access to an orbital superweapon just to get to 1370 W/m^2 sunlight is sheer economic brilliance compared to this one. Oh, wait! Maybe we can combine the two! We can mortgage the next 100 years of human productivity to pay for it, no problem! It's not like we have anything else to do, like ending world poverty, preventing antibiotic resistant malaria from breaking out into a worldwide pandemic, embracing rational thought at the expense of the not-great world religions, and coping with leftover hypernationalism and colonialism from the cold war. So sure, let's do it! Solar cells AND making Earth a ringed or stratospheric smog laden planet!

What could go wrong!


Suburbia is where the developer bulldozes out the trees, then names the streets after them. -- Bill Vaughn