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Comment: Two months eh? (Score 2) 183

by Maury Markowitz (#49485115) Attached to: How Many Hoaxes Are On Wikipedia? No One Knows

When I was in grade school I was taught that the speed of sound increased with density. The examples were air, water and steel.

Actually, the speed of sound goes *down* with density, for the obvious reason that there's more atoms to get through. It goes up with springiness, which transmits the motion more rapidly. The science textbook from school simply selected three examples where the later was true - steel is much springier than air.

This utterly wrong "fact" is still being taught today.

The wiki took two weeks to correct carefully hidden wrong information? I'm supposed to be worried about this?

Comment: Re:Who cares about fusion (Score 1) 57

> Cost effective fusion reactors

Oxymoron.

We *might* build a working fusion reactor someday.

However, we already know it will not be cost effective. Everyone knows this. The head of the French nuclear research group and the director of the Max Planck Institute co-wrote a paper explaining why. So did the former director of the US fusion program. So have lots of other people.

The problem is very simple. A wind turbine consists of a generator, a turbine, and a metal pole. A coal plant consists of a generator, steam turbine, cooling, piping, coal boiler, scrubbers and a very large building. Thus, after initial development during the 1990s and 2000s, wind turbines have become much cheaper than coal plants. As a result, coal plant construction has fallen. You may point to China, but China is installing more wind than coal, as is everyone else on the planet.

And this will be true forever. The inherent comparative complexity of the two systems means that wind will always be cheaper. In fact, even if you skip the boiler, the rest of the plant is still more expensive. Make sure you understand that; a complete wind turbine is less expensive than half of a coal plant.

A fusion plant consists of all of the same parts as a coal plant, except we replace the boiler with a FANTASTICALLY EXPENSIVE fusion reactor, lithium cooling system, tritium extractor, superconducting magnets, etc etc. This part will always, always, be fantastically more expensive than a coal fired boiler. So it will never, ever, be cheaper than wind turbines. Ever. Not even remotely close.

At this point you'll want to say something like "you can't predict the future" or similar twaddle, in spite of science having been invented to do just that. But there's a more powerful counterargument: as it stands, wind is cheaper than a coal plant without a burner. So even if you can build the fusion reactor for zero dollars, no one will build one. So now you start thinking of ways to lower the cost of the rest of the system, inserting unobtanium or some science fiction energy extraction system. The problem is you've just made coal and fission cheaper too.

Comment: How is this a problem? (Score 1) 137

by Maury Markowitz (#49477285) Attached to: Road To Mars: Solving the Isolation Problem

Why does anyone even think this would be a problem?

Did the Homo Erectus walking from Africa to Asia in small family groups often murder each other?

Did the Polynesian cross-pacific crews commit suicide en-route?

Did the native americans all go crazy while crossing the land bridge on the way to becoming native americans?

Does this ever happen on submarines?

NASA has been worried about isolation, sex, and infighting since the 60s. Maybe they should stop asking themselves what will happen, a large group of nerds probably isn't the first place you go to find out about these topics.

Comment: Re:non-traditional batteries? (Score 1) 279

by Maury Markowitz (#49454599) Attached to: The Myth of Going Off the Power Grid

> Even lead-acid batteries are quite small.

Oh god no. According to the EIA average US house uses about 30 kWh a day.

Lead-acid batteries do not like to be run down past 50%, and if you want them to last even a few years, 65% is the minimum. So if you want one day of storage, you'll need 75 kWh worth of batteries. A 75 kWh lead-acid battery bank would fill a bedroom. That is not small.

Li-ion has two to three times the energy density. It can also be repeatedly drawn down to 20%, and that number is improving. So for that same 30 kWh home, you would need about 40 kWh of li-ion, so the total battery bank size would be at *least* 4 times smaller, about the size of a small fridge.

But what you really need to do is just improve the homes. Last year I was burning about 15 kWh a day on average, about 1/2 the average US home, and significantly less than the 25 kWh average for Canada. I replaced all the light bulbs with LEDs and upgraded my computer (which uses less energy), and since then my average is 11 kWh. With li-ion, that would be a beer fridge.

Comment: This article is complete bologna (Score 1) 279

by Maury Markowitz (#49454541) Attached to: The Myth of Going Off the Power Grid

A while back an article was /.ed that suggested that jets were a big problem for GHGs. But they didn't have a single number in the article. If you simply looked up the numbers, you'd find that jets give off 10% of the GHGs that cars do. That means that even if you reduce the jets emissions to zero, that would be as effective as reducing the cars only 10%. And we can reduce cars by 10%. Easily.

The point is that, like any problem solving exercise, you start with the biggest problem and then work your way down the list. And in this case, cars are a much bigger problems than jets, so you start with the cars.

And now we have an article that suggests we shouldn't improve home energy use because that would somehow stop us from fixing the problem in "most of the world". Once again, not a single number.

Well here's some numbers:

http://www.epa.gov/climatechange/science/indicators/ghg/global-ghg-emissions.html

As you can see, the United States and China are the problem. A 10% reduction in China is the same as all of Canada, South America and Oceana put together. So if we're going to fix the problem, that's where you start. And the Chinese are perfectly capable of doing this without our help.

The article is bizarre if you think about it. I shouldn't use LED light bulbs because that lets the power company off the hook to solve their problems? Wow, some logic.

Comment: Re:But we know the Standard Model is incomplete (Score 4, Informative) 73

> the Hiiggs Boson either doesn't exists or has different properties than the Standard Model predicts

Well he got his wish, in a way.

The SM doesn't predict any particular mass for the Higgs. It doesn't predict masses at all, except in the way that it defines relative masses, sort of. So if the mass of particle A is 1 then B has to be at least 2 for the theory to work, but it doesn't say that A has to be 1, and if it's 0.5 then B can be 1. A number of new theories do predict masses directly, or have relative masses like the SM, but require those relative masses to be different.

Right now the entire field is basically up in the air over how to continue development, whether that be supersymmetry or multiple dimensions. They both require different Higgs mass, one around (going completely on memory here) 114 GeV and the other a little less than 140.

Atlas and CMS both put the mass around 125, which means both are wrong. This is a good thing, because both systems stink.

Comment: Re:Uggg (Score 1) 370

by Maury Markowitz (#49424199) Attached to: How the Pentagon Wasted $10 Billion On Military Projects

> What's worth pointing out is that none of these of super-smart people have
> any actual experience with putting warheads in mylar ballons

Ummm, yeah they did. The RBIG's report started development of Minuteman's decoy suite.

> Your entire argument essentially boils down to a false appeal to authority.

The world's leading authorities on the topic. I'll take Hans Bethe's word on the topic over what you offer, which is precisely nothing.

> a good decoy (one which is impossible to distinguish from a warhead), essentially
> replaces a warhead thus reducing the carrying capacity of your missile

You clearly have no idea what you are talking about.

A credible decoy weighs a few kilos. Launch support adds to that. A W87 is maybe 200 to 300 kilos. It is generally stated that you can include 10 credible decoys for every RV, and that even the most basic ICBMs will produce 10s to 100s of decoys, along with chaff, booster fragments, etc. Thousands of objects per ICBM would be typical.

Which is every ICBM and SLBM in the world has been packed with decoys and chaff starting in the 1960s. It's simple and cheap and capable of defeating even the most elaborate BMDs through the midcourse.

> and ABM missiles are much, much, cheaper than ICBM's

The cost exchange ratio is around 20 in favour of ICBMs.

> neglected the developments of the past half century plus

Right, because the laws of physics changed in the last 50 years.

But whatever, there's a massive amount of literature on the topic that can easily be found in Google, dating from the 1950s right into this year. So all the other readers here can peruse that at their leisure and make up their own mind. This will get you started:

https://books.google.ca/books?id=jsH_AwAAQBAJ

Comment: Re: Proprietary formats suck. (Score 1) 109

by Maury Markowitz (#49422973) Attached to: Google Rolls Out VP9 Encoding For YouTube

> Any citations on this?

There's lots. I think the most trustworthy would be this one:

http://infoscience.epfl.ch/record/200925/files/article-vp9-submited-v2.pdf

It used some pretty clever techniques to measure perceived differences, rather than theoretical. H.265/HVEC won very slightly at very high definition, and increasingly won as the bandwidth was reduced. VP9 was "competitive" only at the highest quality settings. At lower settings, VP9 did increasingly poorly, until it was worse than H.264/AVC. VP9 outperformed HVEC on a single data point, for all the other 269 data points HVEC was varyingly degrees of better.

A quote says it all:

"Substantial quality improvements of HEVC coding algorithm in relation to AVC and VP9 are visible especially for lower bit-rates."

> which, if you believe it, would imply that a whole bunch of very smart people at Google have spent several years wasting their time.

Or that a whole bunch of very smart people *over the entire planet Earth* collectively outperformed a smaller number of very smart people at Google.

Comment: Re:Just what we need... (Score 1) 142

by Maury Markowitz (#49422771) Attached to: Stanford Develops Fast-Charging, Stable Aluminum Battery

> Nope, not even close

Here we go, this should be good...

> but moving to EV cars now won't make one jot of difference

Moving to EVs will lower emissions by about one half...

> because the electricity we use to charge them comes from... fossil fuels ...because the energy we use to charge them comes from a mixture of sources that are, on average, far less polluting than a gasoline engine:

https://matter2energy.wordpress.com/2013/02/22/wells-to-wheels-electric-car-efficiency/

Moreover, the most fantastical rate that we could possibly make the move to EV's is slower than the rate we're already greening the electrical supply, so EV's will continue to improve over time at a rate gasoline improvements can't match:

https://matter2energy.wordpress.com/2014/09/16/future-grid-energy-in-the-not-so-distance/

Which is really besides the point, because the emissions of most of the industrialized world is already below the point where you're better off with an EV:

https://matter2energy.wordpress.com/2015/04/01/electric-cars-and-carbon-intensity/

And all that we really need is cheaper batteries, which we should be crossing gasoline numbers around 2020:

https://matter2energy.wordpress.com/2015/04/05/ev-battery-prices-falling-rapidly/

> EV just to claim green credentials is largely an illusion

A statement that you might believe if you've never really looked at the issue or run a single number to back up your prejudices.

Comment: Re:Just what we need... (Score 2) 142

by Maury Markowitz (#49422707) Attached to: Stanford Develops Fast-Charging, Stable Aluminum Battery

> Most of those things (particularly HVAC) can be done with electricity

And for most, georeturn HVAC is far, far more energy efficient than any other source.

It's expensive when everyone has their own tubing, but it seems to me there's a lot of municipal greywater that could be serving this purpose.

Comment: Re:Just what we need... (Score 0) 142

by Maury Markowitz (#49422693) Attached to: Stanford Develops Fast-Charging, Stable Aluminum Battery

> 's just like modern dishwashers; they're far more efficient

I have a brand new Frigidaire dishwasher. It's most efficient cycle, using air drying and "eco mode", uses 22 litres of water, takes 99 minutes to complete, and something like 2 to 3 kWh of power. That is in addition to the gas water heater that supplied the hot water.

I can do that same load of dishes in less than 10 minutes, typically closer to five. I use no electricity to do so, and about 15 to 20 litres of water. Those who use a stoppered sink to rinse will reduce water use significantly.

There are much more efficient models on the market, like the 18" Bosch I had in my last house. However, for north american users at least, the average dishwasher is easy to outperform.

Comment: Re:Just what we need... (Score 1) 142

by Maury Markowitz (#49422601) Attached to: Stanford Develops Fast-Charging, Stable Aluminum Battery

> That won't help until aging hippie hand-wringers stop getting their panties in a twist,
> and get out of the way of us building a lot more modern nuclear power plants

The only thing stopping nuclear power is the cost of the plants.

They cost $8/W CAPEX and come in sizes of 900MW and up. Finding someone willing to put up the tens of billions of dollars needed to build a typical multi-unit plant is difficult in a market economy. That is the reason, *the only reason*, that more nukes aren't being built.

But just think about your own argument for a second. Do you really believe that nukes are so horribly supported that the entire industry has been stopped dead by "aging hippie hand-wringers"? If you really believe that, do you actually *want* that apparently utterly incompetent industry building nukes?

Here's actual up to date numbers, turn to page 11:

http://www.lazard.com/PDF/Levelized%20Cost%20of%20Energy%20-%20Version%208.0.pdf

> Nothing else will even put a dent in it.

Nukes have put a very very small dent in the problem, and it grows smaller every year. Meanwhile, NG, wind and solar are putting huge dents in it, every year. The last EIA numbers suggest that renewables will be installed at ten times the rate of nukes, on a power-delivered basis:

http://www.eia.gov/electricity/monthly/update/
http://www.eia.gov/todayinenergy/detail.cfm?id=20492

Nukes are dead, they committed suicide.

If you steal from one author it's plagiarism; if you steal from many it's research. -- Wilson Mizner

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