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Comment Re:Totally unworkable (Score 2, Interesting) 115

There is enough accessible Thorium and Uranium to power our civilisation at current levels until the sun kills the earth.

Care to back up that claim with solid data? because many experts would disagree with that assessment on uranium. and thorium reactors are still experimental.

Did you actually read the section of the article you linked to? If you did you would have read this: "If one is willing to pay $300/kg for uranium, there is a vast quantity available in the ocean. It is worth noting that since fuel cost only amounts to a small fraction of nuclear energy total cost per kWh, and raw uranium price also constitutes a small fraction of total fuel costs, such an increase on uranium prices wouldn’t involve a very significant increase in the total cost per kWh produced."

How much uranium is in seawater? 4.6 billion tons, roughly one hundred thousand times current annual consumption.

How much can we afford to pay for uranium without driving up the cost of nuclear power significantly? Well, in a year 2.7*10^12 kwh of nuclear powered electricity are produced, with a value of something like 270 billion dollars (assuming an average price of $0.10 or so). To produce this 50,000 tons of uranium are consumed, or about $5000 worth of electricity per kilogram. Looks like paying $300 per kilogram for uranium is unlikely to seriously inconvenience the nuclear power industry.

Comment Re:Money (Score 3, Informative) 115

A lazy and ignorant comment.

You don't know anything about Richard Garwin, clearly. Nor do you understand how Federal funds are allocated. I could go on but that is already a lot of stupidity packed into one sentence.

Richard Garwin is the most distinguished defense scientist in the U.S., and provides scientific advice to the government (like the advice quoted in TFA). At age 85 he is unlikely to be cooking up any billion dollar projects of his own.

Comment Re:Hrm (Score 1) 290

as we share no mitochondrial DNA and the quantity of admixture is ~%4 at most.

That would only indicate that Homo Sapien women were either promiscuous or raped by Neanderthal males, and then the women raised the offspring as their own. Mitochondrial DNA is passed down directly from the mother to the child, so it basically says that Neanderthal men were not welcome in the Homo Sapien society in general, but that cross breading still happened....

What?! The evidence is consistent with Neanderthal men being welcome in Anatomically Modern Human society, but not Neanderthal women!

Comment Re:Idle speculation (Score 1) 290

There are some theories that the Neanderthals were actually quite smart, compassionate, and had a sophisticated social system....

Indeed theories that hold the reverse (that Neanderthals were in some way significantly inferior to modern humans) are actually difficult to support convincingly. Neanderthal sites are far more similar to contemporary H. s. sapiens sites than they are different, and differences that can be well supported are not generally good evidence of any sort of inferiority. The technical skills and tools and social practices of Neanderthals and modern humans are virtually identical for the same time periods. The implicit assumption of inferiority has long permeated and contaminated the interpretations of Neanderthal archaeology.

Comment Re:Idle speculation (Score 1) 290

Personally, I'm more partial to the theory that we *are* Neanderthals (hybrids) and that they didn't 'die out', but were simply bred away...

This is an outdated theory (I used to like it myself though). There is evidence of gene flow between H. s. sapiens and H. s. neanderthalensis, but not very much. Theories that modern humans simply outbred them and replaced them are viable, but not ones that propose that the two species interbred to form a new single hybrid.

Consider this recent article: http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002947 .

A key quote: "Although mitochondrial DNA from multiple Neandertals has shown that Neandertals fall outside the range of modern human variation, low-levels of gene flow cannot be excluded." In other words we definitely are not them, but may (probably do) have some of their genes.

Comment Re:No time to train?! (Score 4, Insightful) 97

You are right to point out the quibble of "no time to train the crew" is straining at a gnat.

But you are having some trouble in trying to swallow the camel. Project Apollo cost $200 billion in current dollars to solve a much easier problem (an 8 day trip) compared to a year-and-a-half trip with an enormously larger delta-vee requirement (if you come back). Perhaps, in a similar national level high priority crash project, like the U.S. undertook in the "space race" it could be done in not much longer than 8 years. But you are looking at something exceeding the cost of Apollo.

Yes, I know Mars One claims they have a plan for a one-way trip that will only cost 6 billion: "The six billion figure is the cost of all the hardware combined, plus the operational expenditures, plus margins." (Emphasis added.)

But they also claim "This plan is built upon existing technologies available from proven suppliers." apparently blissfully unaware of the fact that (as rudy_wayne posted above) that no one knows how to build a workable re-entry system http://www.universetoday.com/7024/the-mars-landing-approach-getting-large-payloads-to-the-surface-of-the-red-planet/ . I guess if you wave away all of the really hard problems its all quite easy.

They also don't address the costs of maintaining the colony in perpetuity - it saves on the really hard problem of return but creates a permanent multi-billion dollar annual obligation to the Earth to keep their colony of four people alive.

Comment Re:The era of Groundbreaking Physics was over (Score 4, Insightful) 470


Anyway, "weirdness" you are talking about is about Quantum Mechanics. Einstein didn't like Quantum Mechanics. Today we know we was wrong by saying "god doesn't play dice".

Time slowing the faster you go is weird. Matter and energy being the same is weird. Gravity warping space and slowing time is weird. Plenty of weird stuff came from Einstein.

Comment Re:This ain't the first time ... (Score 1) 470

It didn't take Einstein.

There was a already a deep, apparently insoluble contradiction in physics -- the ultraviolet catastrophe. Blackbody radiation - a commonplace thing in everyday life - could not be explained by physics (quantum theory would be required). That should have been enough by itself to put claims of the "completeness of physics" to rest.

It didn't since just one glaring anomaly can be dismissed.

And then radioactivity was discovered. Vast amounts of energy appearing from nowhere. That caused the notion that physics was nearly complete to collapse.

Comment Can Anyone Link to the Actual Proposal? (Score 1) 299

As far as I can tell the only information available on this is what Cecilia Kang at the Washington Post says about it. Absolutely everything else seems to be simply a rewrite of her article. Given the track record of any popular media reporting on technical issues it is hard to tell for sure what the proposal actually entails.

This being a non-classified Government proposal circulating freely among businesses, it should be readily available to the public somewhere.

Comment Re:Cue the (Score 1) 299

Absolutely. Not only does the government, businesses, employers, health care providers, schools, etc. automatically assume you have Internet access - and make their plans for interacting with you accordingly, but they are already generally assuming you have high speed Internet access AND mobile phone Internet access also.

Not having Internet access is much like not having access to a telephone 25 years ago - you basically cannot function in society effectively.

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