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Comment Re:Timothy still pushing bitcoin? (Score 1) 267

Bitcoins (the accounting token) is backed by the Bitcoin Network of nodes, software, mining hardware, and all the other stuff that makes it useful. Without the network, bitcoins are just entries in an un-editable database.

This is similar to UPS shipping labels, which by themselves are just sticky paper with some stuff printed on them, of no inherent value. But they are backed by a network of shipping terminals, trucks, and other stuff that makes the labels useful for moving packages, so people are willing to trade money for the labels.

Instead of packages, the Bitcoin Network moves monetary value from place to place, and it does this very well. In one test, it moved some bitcoins halfway around the world, six times, in an hour, for a few cents in fees. The usefulness is why people will trade other money for some units of the accounting token.

Comment Re:Follow the money (Score 1) 267

Transactions only contain the sending and destination addresses, and the amount of bitcoin being transferred. They don't contain any personal information. As long as you don't leak your identity by activity *around* a transaction, they can be anonymous. For example, Coinbase is a company that sells bitcoins to individuals, and you can link your checking or credit card to fund the purchase. So Coinbase knows which coins you bought. But if you buy them in a private transaction from an individual for cash, less info can be revealed.

Comment Re:Establishment clause (Score 1) 277

> A group of native Hawaiians object on the grounds that the land has historic and spiritual significance.

It doesn't. The top of Mauna Kea was used by the natives as a *rock quarry* for stone tools. There is literally tons of archeological evidence of that:

Comment Re:eminent domain for nice [public] things (Score 1) 277

Eminent domain isn't relevant in this case. The land already belongs to the State of Hawaii, under their Department of Land and Natural Resources. Basically the entire upper half of the Big Island by altitude is a nature reserve. The very top of Mauna Kea is a science reserve managed by the University of Hawaii (another state institution). It includes archaeological sites where natives used it as a *rock quarry* for stone tools, and the area where the telescopes are set up.

Nobody has ever lived up there, because there is not enough rainfall to support farming, and it gets quite cold at 14,000 ft. So there was nobody to kick out. Once westerners brought metal tools, they replaced the stone tools, so even the native quarry shut down.

Comment Re:Unhelpful Whining (Score 3, Informative) 277

> We have no business as a society stopping building on the basis of blasphemy anyway.

Except the top of Mauna Kea was never a holy site. It was a rock quarry, there is evidence all over the top of the mountain. Before Westerners brought metal tools, the natives used stone ones, and the lava that erupted up there during an ice age cooled quickly, making it chip-resistant. So they set up mining camps and dug up the mountain top. They didn't live up there, not enough rainfall to grow things. That's also the reason it is a good telescope site. So the natives commuted from lower altitudes, dug up stone tools, and went back down. Not exactly a religious pilgrimage.

Comment Re:And for what? (Score 5, Informative) 277

> "The planned construction site is on land considered sacred by some Native Hawaiians."

What the *modern* natives fail to mention is that the *pre-western* natives used the top of the mountain as a rock quarry. It wasn't sacred at all. Turns out that lava erupted during an ice age, when there were glaciers on top, hardened rapidly, preventing crystal growth. Crystals fracture more easily, so the lack made for excellent stone tools, which the natives used before westerners brought metal tools.

The top of the mountain wasn't habitable for the same reason it makes an excellent telescope site - very little rain. The altitude also means it's cold, and it is high enough to induce altitude sickness if you are acclimated to sea level. So the natives didn't live up there, but rather set up mining camps to extract the rock, then took them back down. There is literally tons of archaeological evidence all over the Mauna Kea Science Reserve, the area on top of the mountain that the University of Hawaii controls. The astronomers are careful about not putting a telescope in archeology areas. There's rock debris, partial tools, shelters, etc. up there.

If it was originally an industrial site, I see no reason not to use it now for a scientific site. It's not like they are knocking down the Parthenon to build a telescope.

Comment Cryptocurrency Advice (Score 5, Informative) 267

> Bitcoin is all the hype, but the blockchain has flaws, in that it isn't as anonymous as one would hope for — you can track past transactions.

Bitcoin transactions record sending and receiving addresses, and the amount sent, and that's it. Privacy depends on how careful you are outside the transaction itself. For example, if you buy something physical online, and give a delivery name and address, the store knows who those bitcoins came from. But compared to a credit card or paper check, which have your name printed on them, bitcoin transactions have the *possibility* of privacy. Cash is no longer anonymous, by the way. Banks and ATMs can scan serial numbers when cash goes out and comes in. Depending how many hand-to-hand transactions happen in between, they can figure out what you were doing.

> Rumors of Bitcoin showing cracks are popping up and also there are quite a few alternatives out there.

The Bitcoin Network is still running fine. They are getting close to a limit in the code originally intended to stop spam transactions. That limits the size of "blocks" of transactions to 1 MB. The current arguments are over how and when to raise that cap. A majority of the network has to upgrade to raise the limit. Yes, there are lots of alternatives, because all it takes is to fork the code and slap a new name on it (it's open source). But as this table ( ) shows, Bitcoin is 7/8 of the market, and only three others have significant market capitalization and trading volume. Building a network of users, apps, etc. for an ecosystem is a lot harder than releasing a new cryptocoin.

> Is getting into dealing with crypto currency worthwhile already?

It was for me, but I started in mid-2011 (from an article on Slashdot, in fact). If it is worthwhile for *you* depends on a lot of things. If you send money to family in another country, or international wire transfers, it may be very worthwhile, because of the very high fees from the other methods. If you are an average US consumer with credit and debit cards and want to shop on Amazon, not so much.

> become easily trackable once NSA and the likes adapt their systems to doing exactly that?

The NSA can download a copy of the blockchain, just like everyone else. What they have, that the rest of us don't, is all the other data collection that can correlate a Bitcoin transaction to a person or place. Like if you are using a smartphone app to send bitcoins, they know who owns the phone and where you were at the time

> What digital currency has the technical and mind-share potential to supersede bitcoin?

What social network is going to replace MySpace? :-). What OS is going to replace Windows? Predicting the future is hard, especially before it happens

> Are there feasible cryptocurrencies that have the upsides of Bitcoin (such as a mathematical limit to their amount) but are fully anonymous in transactions?

Bitcoin can be anonymous, but you have to use it properly for that to happen. As I said above, data leakage *around* a transaction is how you de-anonymize it. The same would be true of alt-coins (the general name for cryptocurrencies besides Bitcoin). If you use them to buy something, the seller may leak your info.

> What do the economists and digi-currency nerds here have to contribute on that?

Economists in general don't have the software chops to understand how cryptocurrencies work, and have religious beliefs on how economies and money *should* work. Not all of them, but a lot of them. My own opinion is bitcoin is the most developed cryptocurrency, with the most users, apps, mining hardware, etc. The direction in the future won't be replacing bitcoin with another coin, but building layers on top of Bitcoin. It's a communication protocol for scriptable transaction messages, and people have barely figured out how to make use of that. As such, it is similar to the IP protocol stack.

Comment Re:BitCoin vs. Global Warming (Score 1) 173

Two reasons. First, the insane competition to mine bitcoins is a temporary phenomenon. We will hit 75% of the 21 million total this July. At that point the reward for mining a block will drop in half, and so will the incentive to mine. Every 4 years half the remaining coins will be mined, and the reward will drop in half again. It was set up this way to encourage early adopters for the initial distribution of coins. Eventually transaction fees, which are ~1% of miner income today, will be the only income. Most miners will give up because it will be unprofitable, or they will get way more efficient. Either way the energy use will go down.

Second, there are half a million bank buildings around the world. Some of them are the largest skyscrapers in town. How much total energy do you think that consumes? Bitcoin mining doesn't use more energy for more transactions. It uses more energy when more people compete for the reward (25 BTC x $370 today, or $9,250 per block, $1.3 million per day, $486 million/year). Network bandwidth and disk space go up with more transactions, but they are not as energy intensive. A world that uses a lot of bitcoin transactions instead of bank branches actually would use less energy in total.

Comment Re:Could it? Or.. (Score 1) 43

My reason is making money by expanding civilization into the Solar System. There are huge amounts of untapped energy and material resources out there. For a description of how the "mining and manufacturing based space program" would work, see: (part 1), and (part 2)

Comment Re:Protection from Cosmic Rays? (Score 1) 43

A 10 ton asteroid tug with 20-25 tons of fuel can return about 1000 tons of asteroid rock to a high orbit, such as near the Moon. That's enough to shield a few Deep Space Habitat modules. Assume the modules are Space Station-sized, about 5x10 m cylinders. You want 1 meter of shielding, which is then a cylinder 7x10 meters, or 188 cubic meters. Chondrite type meteorites have a solid density of 2-3 tons/cubic meter, so the mass would be 375 to 560 tons. So you can cover roughly 2-3 modules. You build a cylinder of storage lockers around the pressure shell of the module, stuff each locker with rocks, and you are done.

The tug takes about 2 years to make the trip to a good Near Earth Asteroid, though the trip time will depend on which asteroid and when you leave. Because you want to use it as shielding, you grab dust and small rocks off the asteroid surface, and not big chunks. Later you can process the rock to extract water and other useful stuff. Since the tug's engines and solar arrays have a life of ~15 years, you can make multiple trips. The first one is for shielding, the ones after that are for processing.

10 tons of vehicle hardware should cost about two large comsats, or ~$600 million. It's mostly solar arrays and electric propulsion units, with enough multiples of each that a failure or two doesn't doom the mission. Each time the tug returns, you can fix whatever breaks before the next trip. The first load of propellant has to come from Earth, but the later trips can use water extracted from your asteroid rock.

Comment Re:It's really too soon for this post. (Score 4, Informative) 118

> I do wonder how feasible it would be to build some sort of a hydraulically stabilized landing platform on top of the barge

Look up "Sea Launch", which was a partnership between Boeing, Kvaerner A.G. (Norwegian ship and drilling platform builder), and Russian rocket companies. They launched rockets from a converted drilling platform out in the Pacific Ocean.

A semi-submersible platform like that takes on ballast water to lower the center of mass below the waves, while the platform on top is held *above* the water on columns. The waves can then pass through the columns without moving the platform much, because it's not a solid wall like the side of a ship. The ballast water mass also makes the whole platform more massive and hard to move.

Right now (or very soon) you will likely be able to pick up drilling platforms for scrap value. With the price of oil so low, expensive ways to extract oil, like fracking and ocean drilling, can't make a profit, so the drilling companies stop doing it, and some of them go bankrupt.

Comment Re: Who cares? (Score 1) 90

That exact calculation was done by the Silk Road prosecutors, so we know that 4% of bitcoin transactions were for drugs during the time that marketplace was operating. Whereas for the world economy in general, illegal drugs account for 3% of GDP. It's not an entirely different picture, it's the same picture.

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