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Comment: Ores [Re:A niche product in a niche market] (Score 1) 474

by Geoffrey.landis (#49792759) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

You're aware that lithium is a rare earth element, right?

First, lithium is not a rare earth element.

http://www.rareelementresource...

Second, you do know that the rare earth elements are not actually "rare," right? They are roughly the same abundance as copper.

There's no such thing as lithium ore.

Sure there are. "Ore" is just a word meaning "a mineral deposit containing a desired substance in economically recoverable concentrations." Lithium ores are typically lithium-containing phyllosilicate minerals, often in the form of evaporite deposits.

You strip mine millions of tons, process it and get a few tons in return.

Comment: Re:faster than light = time travel (Score 1) 201

"If you could, either relativity is wrong, or you can use this to make a time machine to access the past."

Well, relativity is most certainly 'wrong', in the sense that there is more to the universe that it does not cover.

Saying "there are things it doesn't cover" is not the same as saying "it's wrong."

Of course, that's not really wrong, any more than Newton was wrong. Newton was not attempting to model relativistic effects, and Einstein was not attempting to model string theory. And luckily, we are not made out of light, so the speed of light has little to do with

The phrase "speed of light" is historical usage. An equally accurate phrase would be the universal conversion factor from units of space (meters) to units of time (seconds). It doesn't apply just to light, it is a universal constant that applies to pretty much everything in the universe, not just light. Most particularly, it applies to gravity.

a machine designed to alter a local region's gravitational constant,

If you alter the gravitational potential, the gravitational time dilation will mean that external observers will observe your speed of light as having changed. If you're in a gravity well, your clocks have slowed down, so it looks (from the outside) as if light has slowed down. But, inside the region of altered gravitational potential, if you measure the speed of light, it's still moving at the speed of light. You can't travel faster than the speed of light where you are.

that can travel at arbitrary speeds relative to the destination because it carries it's own engine with it. Relativity does not forbid a starship.

If you could travel at arbitrary speed (in any direction, in any reference frame), relativity says you could make a time machine. Space is time. If you can travel faster than the speed of light you can travel backwards or forward in time.

But none of that would ever allow you to travel back in time. That would be akin to traveling in a negative direction.

Right. If you can travel faster than the speed of light, but only one direction, then you can't make a time machine.

Comment: faster than light = time travel (Score 1) 201

Nothing can go as fast as light. Slower or faster, sure, but not c.

Light goes as fast as light.

More specifically, you can't send MATTER, ENERGY, or INFORMATION faster than the speed of light IN VACUUM.

The fact that there are "things" that travel faster than light (such as phase velocities) is well known; in these neither the matter nor the energy travels faster than light, and they don't carry information.

If you could, either relativity is wrong, or you can use this to make a time machine to access the past.

Comment: Re:Ozone layer is recovering (Score 1) 113

And, how does this all relate to the much-feared, much-publicized "global warming".

Short answer: it isn't. They are unrelated phenomena.

I must note that the hottest decade on record was the same decade in which the ozone layer was most depleted.

Factually incorrect.

Comment: One web site. (Score 4, Insightful) 434

by Geoffrey.landis (#49778823) Attached to: Creationists Manipulating Search Results

The actual article seems to only say that one web site, titled "What really happened to the dinosaurs", appears in response to one particular search query, "What happened to the dinosaurs".

That's annoying and stupid... but it's not the same as the hyped headline "creationists manipulating results."

Comment: The problem is... (Score 1) 232

by Geoffrey.landis (#49777555) Attached to: Elon Musk Establishes a Grade School

The problem is...

The problem is that there are tens of millions of children needing education.

A school teaching tens of children (that have been hand-selected to attend) may be heartwarming, but it's irrelevant by factors of millions. With sufficient resources, it's easy to teach ten or twenty students (especially if you're allowed to select which ones).

It's replicating that by a million times that's hard.

Comment: Design Life is not Expected Life (Score 3, Insightful) 136

I mean with all the technical miracles NASA pulled off on that mission, they somehow managed to underestimate the longevity of the mission by 45x.

To be fair, 90 days was not, in fact, the estimated lifetime of the mission. It was the design specification of the mission. That is, each of the subsystems was designed with the specification "design a system that will operate for a minimum of 90 (Martian) days, even under worst-case conditions."

Think of it as a 90-day warranty-- after 90 days, it wasn't expected to be dead, it was just out of warranty.

(and note that since the engineering specification was validated by testing the subsystems to either three times design life, or testing to design life under three-sigma worst-case conditions, it would have been very difficult to design for 4000 days...)

Comment: Next version, orbit [Re:What's the point ?] (Score 4, Informative) 76

by Geoffrey.landis (#49595027) Attached to: Jeff Bezos' Blue Origin Launches Its First Rocket

why Jeff Bezos is doing the same thing that SpaceX is already doing ?

They're not, New Shepard is a SUBorbital craft not an orbital one. I don't know if there are even any plans to make an orbital version...

From https://www.blueorigin.com/new...
"We continue to be big fans of the vertical takeoff, vertical landing architecture. We chose VTVL because it’s scalable to very large size. We’re already designing New Shepard’s sibling, her Very Big Brother – an orbital launch vehicle"

So: yes.

Comment: To expensive to dump spray on the ground (Score 1) 678

Desalination is a plausible solution for water for consumer use--that is, urban and suburban locations.

It is not a very plausible solution for agricultural use-- too expensive.

Actually, there are a number of issues with desalination as it presently exists. The cost of plant construction and operations puts the cost of water supply at roughly triple that of traditional methods.

Exactly. That's why it's not a plausible solution for agricultural use. If your application is to take water and spray it on the ground, yes, it needs to be cheap.

For urban and suburban use-- well, given the rents, and the cost of housing, in San Diego (not even to mention San Francisco!)-- the cost of water just isn't a factor. You could triple it and not notice.

They also depend on fossil fuels and thus contribute to greenhouse gasses. They produce brine and boron contaminants that can not easily be disposed of on either land or sea without potentially significant impact of the wildlife exposed to them.

Those are engineering problems.

Comment: It's not drinking water that's the problem here. (Score 1) 678

The 2 "crops" that are taking the water:

  • Alfalfa - going to China to feed THEIR livestock.
  • Bottled Water - Nestle's is buying municipal water at residential rates and selling it back at 100s of times the original cost.

Shut those 2 things down and water problem solved.

You are clueless.

Look, I hate Nestle and I think bottled water is stupid too, but the amount of water they bottle is trivial compared to the trillions of gallons of water shortage representing the drought. They could bottle a hundred times more water, or a thousand, and it still wouldn't make a lick of difference.

The problem is measured in trillions of gallons. It's not drinking water that's the problem here.

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