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Comment: Re:Satellites have eclipses (Score 1) 230

by mangu (#46845585) Attached to: How Japan Plans To Build Orbital Solar Power Stations

Wut? Unless that set period is so short it needs building additional facilities, the price for repeated launches will only go down, never up.

Imagine the time period is the same you need for building a 1 GW power plant using any traditional technology. That will be a few years. Meaning you could do a launch every couple of days and complete a thousand launches in the same period. You could do that from a single launchpad.

The reason why they don't do launches day after day right now is because there is no demand for so many launches, but they certainly could adapt the procedures for that.

Comment: Satellites have eclipses (Score 1) 230

by mangu (#46843691) Attached to: How Japan Plans To Build Orbital Solar Power Stations

In the geostationary orbits there are two periods each year, around March and September, when the satellites are eclipsed by the earth. That's why geostationary satellites need batteries, which are among the heaviest parts of a satellite. And, unfortunately for the power generation idea, these eclipses occur at night for a satellite located above the point it's beaming at.

As for the cost, launching 10,000 tons could be done for something like $50 billion or so. We are talking about a thousand launches, so it would pay to build your own rockets, which would bring the price down.

The exact costs of the launchers today is a closely guarded trade secret, but it's certainly less than the price you pay. Certainly, with a private company with development costs amortized over a thousand units, they could bring the launch costs to a less prohibitive level.

Comment: Re:Bank them (Score 1) 333

by mangu (#46843557) Attached to: Blood of World's Oldest Woman Hints At Limits of Life

trying to force a 100 year old body to keep it's heart beating

Hint: by the time science discovers more about the mechanism of aging, it won't be a 100 year old body anymore.

All of her white blood cells were being produced by just two stem cells. Imagine if they could replicate stem cells indefinitely, her body would become 20 years old forever, not 100.

Comment: Re:Philosophy is the opposite of mathematics (Score 1) 306

by mangu (#46814029) Attached to: Our Education System Is Failing IT

I took a philosophy course and an engineering degree. After working 30 years in engineering, I can tell for sure that philosophy is NOT the answer to engineering problems.

If too many people working on IT are under trained, you may blame the education system for failing to provide them with enough training in that field, not for failing to provide them education in totally unrelated fields.

Comment: Philosophy is the opposite of mathematics (Score 0) 306

by mangu (#46813809) Attached to: Our Education System Is Failing IT

Philosophy to come up with the right argument and psychology to make it stick

Unfortunately, philosophy is very far from coming with the right argument. I took a philosophy course in college, to "broaden" my outlook, and it had the exact opposite effect. Read any text by a philosopher, and in the end you'll get to the conclusion that perhaps there could be one or two good ideas there, if it had been written in a hundred words instead of a hundred pages. That's why sometimes a philosopher seems so smart to the uninitiated, they have read only the aphorisms and quotations, they have never had to pore through a full book written by a philosopher.

IT is a field for many different specialists. In the most common forms, what is needed is an expertise in human interfaces, we need graphics designers to create the screens and writers to create the documentation. In that sense, yes, it's all about expertise in the humanities. The vast majority of IT work in development is about personal and corporate software, of which data input and presentation is the bulk of the thing.

Logic and mathematics, although it's behind every software, is a very small part of the development job. However, it cannot be totally disregarded, because it's an essential part.

There's the dilemma we face. We cannot just exempt people working in IT from training in the essential parts most of them will never use, because we never know when those skills will be needed.

Those programmers who say "I've never used a differential equation" are people who slept through their calculus courses and cheated at the exams. If you are simulating pitching a ball or you are calculating the profits from an investment fund you are using differential equations, and you should know how to do the job. Unless you work for a big company, you cannot be assured that the only things you'll ever need to do is drawing screens and writing manuals.

Comment: Terrorists, not tourists (Score 1) 239

I guess the memo had a misspelling. The wheel wells seem to be a good place for terrorists, not for tourists.

If someone can sneak up to the plane and climb in, it should be equally easy to put a bomb there. If a 16-year-old can find a way to squeeze into that space, it wouldn't be too difficult to fit in a couple hundred pounds of explosives.

Comment: ANY delay destabilizes the system (Score 1) 342

by mangu (#46685089) Attached to: Australia May 'Pause' Trades To Tackle High-Frequency Trading

If you need to sell some stock or commodity within a second of buying it, then something is wrong

Oh, yeah? Then, please, tell me in your infinite wisdom how long I should wait? Ten years? Twenty?

The fact is that ANY delay in a feedback system tends to destabilize it. In mechanical systems this is called "backlash" and there is extensive research on how to eliminate it and cope with the problems it causes. Anyone who proposes to artificially introduce backlash in a feedback system know nothing about what he is talking about.

In a market it would be trivially easy to manipulate prices if an artificial delay were involved, especially for the bigger traders. Put a buy order for a million shares and watch the prices rise, then sell at the higher price that would result a half second later. The same principle would work no matter how long the delay is.

Markets work so well because there is negative feedback in many different loops all over the economy. Some of these loops have shorter response times, other are slower to respond. If you invent an artificial delay that overlaps everything, this creates a well defined eignevalue that anyone with the proper technical knowledge could exploit.

Comment: Tax == Arbitrage (Score 2) 342

by mangu (#46684831) Attached to: Australia May 'Pause' Trades To Tackle High-Frequency Trading

Imposing a tax only means the profit threshold is raised. That creates the market distortion called "arbitrage", where the relative costs between different transactions are not symmetric.

A .01% tax per transaction would mean that for me, a small trader, there would be a net loss unless my own profit per trade is lower than .01%. For a bigger trader, the cost per trade is lower, therefore they would gain and advantage over us, the smaller guys.

The true solution? Let it be, do not change anything.

Apart from some guys who get a lot of profit selling books claiming HFT is bad, no one actually makes very much on HFT. The margins are very low, extremely low, so you need to invest a lot of capital to get any profit from it.

Getting a small profit from economy of scale is something that hurts no one, it happens in every sector of the economy. As a small investor, I have an indirect gain from the higher liquidity when the big investors go into HFT.

The economy is not a zero-sum game, there are situations where everyone profits and situations where everyone loses. With HFT everyone gains, with taxes everyone loses.

Comment: Re:Greatest, but maybe not the most damaging (Score 1) 102

by mangu (#46642021) Attached to: Book Review: How I Discovered World War II's Greatest Spy

The US didn't need to use the bomb again, the mere knowledge that it existed was enough.

Anyhow, it was several years until the Soviets got their own bomb, and even longer until they had some way to deliver them. Until the mid-1950s at least the Soviets had no bomber planes or missiles capable of dropping atom bombs on the USA.

Comment: Re:I'm not covinced by Dyson (Score 1) 125

by mangu (#46210747) Attached to: Dyson Invests £5 Million To Create 'Intelligent Domestic Robots'

And don't someone come up with the BS about everyone will sit around in blissful nirvana writing poetry or music or coding or go kayaking all day.

No, of course not. They will sit around and watch TV.

How many people have the ability and the inclination to write poetry or music or code anyhow?

Comment: Voice needs context (Score 1) 113

by mangu (#46084765) Attached to: Google Buys UK AI Startup Deep Mind

Voice interface is one of the hardest things to implement well in AI because there are so many sentences that sound similar, understanding depends so much on context.

Without understanding the context of the conversation, a voice interface will not be able to know if you are talking about sodas or sawdust, robots or row boats, new displays or nudist plays.

Comment: Bye bye, aircraft carriers (Score 1) 197

by mangu (#45953599) Attached to: How Quickly Will the Latest Arms Race Accelerate?

work on space exploration, fusion power, renewable food production,

You know what's even worse than working on developing weapon systems? Working on 90 years old weapon systems.

Aircraft carriers were state of the art during WWII, today they are as obsolete as the USS Arizona was in 1941.

What's the point is spending hundreds of billions of dollars in building sitting ducks that can be taken out by a single hypersonic missile?

"I may kid around about drugs, but really, I take them seriously." - Doctor Graper