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Comment: Re:proposed hyperloop goes to proposed city (Score 1) 75

by Immerman (#49154753) Attached to: Hyperloop Testing Starts Next Year

The problem with maglev is it's *expensive* - every mile of rail needs not only a better-than-normal-rail foundation to survive the stresses of high-speed transit (maglev only eliminates the high-frequency vibrations), but also a "track" of either extremely powerful permanent magnets, or an active maglev system. And reliabilty must be *extremely* high, since losing power for even a second means your high-speed train is going to cease to levitate and tear up a goodly length of expensive track, in addition to probably destroying itself and its passengers.

Hyperloop on the other hand is basically just a length of vacuum tubing on stilts, with occasional vacuum pumps along its length to compensate for leakage, and magnetic "mass drivers" wherever there's need for a speed change - all the rest of the cleverness is in the cars themselves, which float on a cushion of air like an air-hockey puck. And anything but the most catastophic of failures will result in the cars coasting to a stop as the air density in the tube gets too high to support their speed. Between the technical simplicity of the tubes, and the long stretches between pylons where the ground doesn't need to be prepared at all, Hyperloop track is potentially cheaper per mile to construct than rail, even in rural areas, and in urban areas rail can't begin to compete.

Comment: Re:Work obviously not done by biologists (Score 1) 46

by Immerman (#49154577) Attached to: Methane-Based Life Possible On Titan

And unicorns *may* suddenly leap out of my bum, but without some form of supporting evidence for that claim I'm not going to take it seriously. All life we know of depends on cell walls to maintain a sufficient density of organic chemistry, and now we know that cell walls functionally much like our own could exist on Titan, using compounds we already know exist in the atmosphere. That's a big boost for the argument that there might be life on Titan.

As for porous materials - life might well start there, but it's not likely to get very far unless its chemistry is either all bound to a single macro-molecule, or is contained within some sort of semi-permeable envelope. The very porosity which contained the chemistry would also severely restrict the flow of energy and nutrients, so that probably only a very thin layer of pores could support life, and the first bit of life that found a way to leave its prison would have a bounty of resources at its disposal beyond anything its ancestors could have "dreamed" of.

Comment: Re:based vs inhaling vs exhaling (Score 1) 46

by Immerman (#49154495) Attached to: Methane-Based Life Possible On Titan

Slashdot summaries are confused, when not outright inaccurate - news at 11. If you actually want to know details, you're pretty much required to RTFA.

As for your question, humans (/mammals/animals/multicellular organisms) are a recent addition, not typical of Earth-based life.

Earth life is water-based (well, suspended anyway), with lipid(hydrocarbon)-based cell walls to keep vital chemistry sufficiently concentrated to continue. Eventually blue-green algae evolved their ability to photosynthesize and poisoned the planet with toxic oxygen byproducts, which some of the survivors later managed to harness as a fuel. But that's really an incidental development so far as life itself is concerned. Before that life was all chemovores - likely consuming complex organic molecules from either hydrothermal vents and/or their fellows for both nutrients and energy.

In this case researchers have found some other hydrocarbons that can form "cell walls" with properties very similar to those in our own cells, except that they operate in a liquid methane suspension instead of water, at temperatures that would render our own cell walls solid. One of those hydrocarbons is acrylonitrile, a compound found in Titan's atmosphere, so the building blocks for cell walls at least are already present there.

Comment: Re:So live underground (Score 1) 128

by Immerman (#49152019) Attached to: Adjusting To a Martian Day More Difficult Than Expected

They're probably misrembering slightly - the moon has a two-week day, followed by a two-week night, for a full diurnal cycle almost exactly the same as it's orbital period around the Earth (it's tidally locked after all). The discrepancy is of course due to the fact that the Earth completes about 1/12th of an orbit around the sun per one rotation of the moon, so the length of a lunar sol is slightly different than the rotational period - just like with the Earth itself, but more dramatic since a lunar month/day is a lot longer.

Comment: Re: A rightwing wankfest? (Score 1) 89

by Immerman (#49151961) Attached to: Fighting Scams Targeting the Elderly With Old-School Tech

You're talking catch, not quantity of available fish - catch naturally increases with better technology, but as available fish reserves are depleted that only makes the problem worse. Both total mass of fish, and individual specimen size have been declining for a *very* long time. But hey, maybe we can learn to eat jellyfish, they seem to be thriving in the warmer, less predator-rich waters.

Comment: Re: A rightwing wankfest? (Score 1) 89

by Immerman (#49147383) Attached to: Fighting Scams Targeting the Elderly With Old-School Tech

Actually, no. What you're forgetting is that the planet is *huge*, even the massive consumption of the entire human race is only a tiny fraction of it's total capacity biomass.

We are currently consuming biological resources at somewhere between 1.5x and 2x the rate at which the planet can produce them. Remember it's a living, *growing* system - so long as we consume things no faster than it grows, the system is sustainable. As it is though we're "spending the capital" - not only are we consuming the new growth, but we're also reducing the "base" biomass so that, on average, next year things will grow more slowly than they did this year, and that trend will continue until we reduce consumption sufficiently.

Fishing is probably the most obvious example of this - go find some photos of the docks with fishermen showing their prizes from the 1800s: huge 4-8 foot fish all over the place, while today you rarely see anything over a couple feet. We've been "strip-mining" the ocean for centuries, and as a result the total yields have been falling for almost as long.

Comment: Re:amazing (Score 1) 279

by Immerman (#49138209) Attached to: Intel Moving Forward With 10nm, Will Switch Away From Silicon For 7nm

Fair point on the factor of ten.

As for being single bit units - they may only have a single-bit output, but they have thousands of analog-weighted inputs, plus a memory of past states, all being used to determine exactly when it fires. And the brain being an un-clocked chaotic system, the exact timing of that firing may have dramatic effects downstream. So really, even though the firing potential offers only a single-bit transition, there's an analog range of timing-encoded output.

Actual neurons are radically more sophisticated than the glorified adders used in a programmers "neural net".

Comment: Re:Nothing important. (Score 1) 201

by Immerman (#49138005) Attached to: What Happens When Betelgeuse Explodes?

Thoughts are nice, but unless there's actual evidence, a thought is all it is. Personally I suspect that the woman who is struggling to keep two kids fed knows damned well that a third kid is going to mean someone is going to go hungry, and it tears at her heart to realize that sooner or later that is going to become reality.

It's not calculus, every parent knows that children are expensive. "All" you need is a social outreach program to let people know that the world has changed, and every child can be a *choice*, one that can be cheaply and easily declined, or delayed until you can afford it better. The difficult part is swaying social expectations, not explaining the premise.

Comment: Re:Wrong! (Score 1) 356

by Immerman (#49130133) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt

Another important benefit of solar is that the lack of necessary infrastructure gives it *incredible* potential in the developing world, whose power consumption is growing rapidly, and for whom coal is currently the only realistic alternative. But for it to really take off the price needs to be driven down even further, and subsidies in the developed world help us reach the economies of scale necessary to make that happen.

I have hardly ever known a mathematician who was capable of reasoning. -- Plato