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

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) 281

> 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) 281

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

> 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

> 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

> 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 0) 142

> '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

> 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.

Comment Uggg (Score 4, Informative) 370

While I've long been a critic of all ABM programs, and so should in theory agree with the basis of this post, but this article downright stinks. It is clear the author doesn't really understand any of the technical issues he writes about with feigned authority. The baseball analogy section is particularly laughable, picking apart a dumb offhand statement while utterly missing the entire point of the analogy, and failing to consider the issue that the radar can't possibly do what it claims to anyway.

For those of you interested in all of this, I suggest you read the Wiki article on Nike Zeus. The problems with decoys were well known in 1958, and panel after panel of the super-smart (including nobel laureates) examined the issue in depth and basically said that a good decoy is literally impossible to distinguish from the warhead. Why? Because you can put the warhead in a mylar balloon and launch several similar balloons on nearby trajectories, and that's basically that.

Everyone has been aware of this issue ever since. Nike-X and LOADS were invented to work at much lower altitudes, where the decoys were no longer a factor (they're balloons, they begin to float once they start to re-enter), while the PRESS series attempted to find differences in ionization or other physical effects of the earliest stages of reentry to the same end. Both ultimately failed - Nike-X could be overwhelmed with MIRV for almost zero cost, and PRESS demonstrated that no such measurable difference actually exists.

No amount of engineering can fix this. All you can do is hope that the decoys have bad trajectories or tumble, with the later being of zero use if it's spherical. It is entirely possible that North Korea has bad decoys, but given that the UK built really good ones in the 60s as part of Chevaline, its certainly not a $10 billion bet I'd make. And then there's the killer problem - you deliberately launch the RV on a "bad" trajectory so its not a threat, and then maneuver after the midcourse onto the target. This problem killed Hardsite, and it only had to work over about 10 miles, not 10,000.

I'm not saying that BMD is a bad idea, but everyone should be perfectly aware that any BMD can be penetrated with some degree of ease. The question, as it has been since the 50s, is whether by spending XXX dollars on improving the defense can be offset by spending XXX on better penaids. NK is a poor country so its a question to ponder, but for anyone else the answer is, and always has been, that it's about 20 times cheaper to penetrate the BMD than build it.

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