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Comment: Working fusion reactor (Score 1, Funny) 315

by superposed (#48096169) Attached to: Fusion Reactor Concept Could Be Cheaper Than Coal

I already have a working, self-sustaining, exothermic fusion reactor. I made it pretty big, so that the necessary pressure is created by gravity alone. This design produces 400,000,000,000,000 terawatts and is completely maintenance free. It also uses a passively safe design so the reaction can't run away, at least for a few billion years. I managed the containment issues (and the truly excessive power production) by suspending the reactor in vacuum about 100 million miles from any population center. Rather than building a 100 million mile cable, I'm transmitting power wirelessly via medium-wavelength electromagnetic radiation. The reactor uses a simple blackbody emitter to generate the radiation. Unfortunately, I couldn't afford to build a good focusing system at the reactor site, so only about 1/10,000,000,000 of the power (50,000 terawatts) actually reaches my potential collector site. However, we only need 13 terawatts to serve our potential market, and really more like 4 terawatts if we can convert the energy to electricity.

Now I'm just working on a system to convert this medium-wavelength electromagnetic radiation into electricity at the collector site. A lot of the fusion reactor designs I've seen use the radiation to boil a fluid to run a turbine. But I'm thinking it would be much cooler to use semiconductors -- maybe use the electromagnetic radiation to excite electrons across a bandgap and create electricity directly? I've got working prototypes of the solid-state converters, and they're already pretty cheap -- I can produce electricity for about 15 cents per kWh. I think with a few more years' work the whole system will be cheaper than coal power (it helps that I don't have to pay for the reactor or fuel). I figure if I cover 0.05% of my collector zone (the Earth's surface) with 15% efficient converters, I can provide enough energy for everyone on the planet.

Comment: Name one (Score 1) 291

Could you please list one or more of these end-of-the-world scares that had as much scientific consensus as climate change, but turned out to be unfounded? Environmental history has more often been a case of "don't worry about it, don't worry about it" until the resource collapsed -- DDT, Cuyuhoga River, ozone hole, atlantic cod fishing, ...

Comment: Obligatory car analogy (Score 1) 291

Passenger 1: "You're steering too far to the right -- you're going to go off the road!"

Driver: "No way. The gap between our car and the edge of the road is tiny compared to the size of the whole road. Reducing it won't have any effect."

Passenger 1: "That's irrelevant. If you cross that margin, the car will go off the road!"

Driver: "No way. You and Passenger 2 can't agree about when the car will leave the road. So there's no problem."

Passenger 1: "But we both agree you'll go off the road if you keep going to the right!"

Driver: "Hold on, let me wade into the science here. You say the road slopes down at the edge, and Passenger 2 says it slopes up. Maybe it goes up steeply near the edge. That would slow us down. So there's no problem."

Passenger 1: "But it's just as likely to slope down! If it slopes down enough, we'll accelerate out of control. And no matter how the road slopes, you can't keep driving to the right forever. Eventually you'll leave the road."

Driver: "But I like driving this way. Besides, you guys still haven't agreed about what will happen if we leave the road. Or when that will happen."

Passenger 1: "But surely the smartest thing is just to steer back to the center rather than risk catastrophe?"

Driver: "Maybe we could build an extra section of road further off to the right. Or we could strengthen the car so it keeps running even if we leave the road. You guys should go study that and leave me alone. I like driving this way."

Comment: Re:The death-knell of US cloud providers... (Score 1) 771

by superposed (#44514639) Attached to: Encrypted Email Provider Lavabit Shuts Down, Blames US Gov't

Clearly the operator of Lavabit received a national security letter or warrant which he objected to. ... I suspect that the request was not just something mild ("This sleazebag's mail account") but something broader, given the reaction was to close down the service completely.

As I read this article in the NY Times today I thought, "Hmm, how can the NSA search the contents of all e-mail leaving the U.S.? What about e-mail from one gmail user to another? Or messages sent between servers using SMTP with SSL? Surely NSA can't decipher those just by cloning the transmission links." Well, this may be the answer -- force the e-mail providers to hand over copies of any messages sent to or from machines with foreign IP address, or written or read via webmail on a foreign machine.

But don't worry, FISA will prevent NSA from obtaining copies of purely domestic e-mail or keeping copies of these messages for more than a few seconds.

Somehow I'd rather have a public discussion of what NSA can and cannot request, rather than relying on a secret court to protect our constitutional rights.

Comment: With USB, charging and HID are mutually exclusive (Score 1) 303

by superposed (#41018841) Attached to: First Pictures of Apple's New Mini Connector

You suggest controlling volume and playback by having peripherals act like USB keyboards ("support HID"). But in the USB world peripherals can only be connected to hosts (e.g., PCs), not to each other. And currently iPods and iPhones act as peripheral devices, making it impossible to connect them to other peripherals (e.g., devices that act like keyboards). This is true both logically and physically.

To be more specific, iPods and iPhones either have to act as peripherals and use a Type B USB connector, or have to act as hosts and use a Type A connector. In the first case, they could charge and send out audio and video using the approaches you suggest, but they can't receive HID information (as far as I know). In the second case they could receive HID information, but I don't think they would be able to charge or send out audio and video.

Maybe it's time for a true peer-to-peer replacement for USB?

Comment: Snapz Pro on your end (Score 1) 96

by superposed (#39494771) Attached to: Slashdot Asks: How To Best Record Remote Video Interviews?

I highly recommend using Snapz Pro X on your end. This can record all the audio and video that shows on your computer (which must be a Mac). You would just need to setup a Skype call with your interviewee, start recording and off you go. You can also set it to record only a section of your screen (e.g., the main Skype window). I've used it to record PowerPoint lectures pretty successfully (including ambient audio).

I believe iChat can have better video quality than Skype, but it is not sufficiently cross-platform for all your interviewees. So you're probably stuck with Skype unless you want to start posting videocameras back and forth to your interviewees.

You would probably do well to make a separate recording of the interviewer using a videocamera, and splice that in to the interview.

Comment: Most finance sites don't allow symbols (Score 1) 601

by superposed (#38432530) Attached to: Do Slashdotters Encrypt Their Email?
I use a similar password system (a basic formula with 8 characters, including letters, numbers and symbols, and a way of changing it for every application). This works well for most purposes (e-mail, academic logons, etc.), but generally not for financial websites (my credit card company, bank, brokerage account). So I have a different system for financial sites that _doesn't_ use any special symbols. This seems like a bad idea. Why would any website (especially one that wants the highest security possible) forbid the use of certain characters?

Comment: Terrible for long-distance travel (Score 1) 990

by superposed (#37229986) Attached to: Ask Slashdot: Could We Deal With the End of Time Zones?
This idea would solve one set of problems (synchronizing events across time zones or figuring out the local time while traveling), but would create a whole new set of problems for long-distance travelers.

Currently people everywhere have a common set of expectations about what time the sun rises, when to eat meals, when to sleep, etc. If you travel to a new region, you change your clock once, and you're instantly slotted in to the local expectations. On the other hand, if we followed the proposal above, travelers would have to do timezone-type math for all these events every day.

Say you travel from California to Japan. What time will the sun come up? Well, at home in California it comes up at 14:00 UTC. California is around 120 degrees W and Japan is around 138 degrees E, so Japan is about 360-258=102 degrees east of California. The sun travels 15 degrees per hour, so events will happen about 7 hours "later" in Japan than in California. Add 7 hours to 14:00 and you can expect the sun to come up around 21:00 UTC. Great. Now what time should you make a lunch appointment with a colleague? Usually in California you have lunch at 20:00 UTC, so add 7 hours, modulus 24 to get 03:00 UTC.

It's a lot of work, but at least you'll know when to catch your flight home without adjusting your clock. You just won't know (without some math) whether that will be the middle of the night, first thing in the morning, etc.
This does not strike me as easier than the current system.

Comment: AIG in 2008 was safer than U.S. Treasury in 2011? (Score 4, Insightful) 1239

by superposed (#37005058) Attached to: United States Loses S&P AAA Credit Rating
It's amazing to me that until September 2008, S&P was giving AIG a AAA rating, even though AIG was taking the bad side of everyone's bets on the mortgage market, but now S&P downgrades U.S. debt over concerns about "budget deficits and rising debt burden." The U.S. government still has plenty of room to raise revenue to pay off Treasury Bills, and may even be Constitutionally obligated to do so.

It's just hard to believe that the U.S. Treasury is now considered a riskier borrower than AIG was in 2008. It's also ironic, since a good part of the U.S. debt burden was incurred bailing out AIG and the rest of the financial industry (which assumed AIG credit-default swaps would protect them, in part due to S&P's high rating of AIG).

Comment: Re:Complex Model (Score 1) 464

by superposed (#36669854) Attached to: China's Coal Power Plants Mask Climate Change
The ever-improving climate models don't actually give estimates of the climate's dependence on CO2 that are much different from the simplest models. Given how long it will take to change our energy system, does it make sense to take action based on our best estimate of the effect of CO2 now, or wait until that estimate is perfect, which may never happen? In your opinion, when would we know well enough to declare climate change a problem and begin doing something about it?

A related question for climate change doubters: Suppose hypothetically that emissions of CO2 really were on track to cause harmful climate change. How would scientists' behavior and results differ from what we're seeing right now? Are you ruling out climate change based on the predominance of the evidence or because you'd rather not believe in it?

Comment: Re:Complex Model (Score 4, Insightful) 464

by superposed (#36660238) Attached to: China's Coal Power Plants Mask Climate Change
Yes it's a complex system, but that doesn't mean we have to understand every last detail before we take action. We've known for over a hundred years that CO2 is transparent to visible light and absorbs infrared. Therefore, adding CO2 to the atmosphere will cause warming (allowing sunlight in, but reducing the amount of heat radiated back to space). The only scientific question left is how much warming, where and when. The most natural (and safest) assumption is that adding CO2 to the atmosphere will change climate. "We should wait until we perfectly understand this insanely complex system" is not a rational response.

People can differ over whether they think climate change will be a bad thing, or whether they should have to pay to prevent bad things from happening to other people or the natural environment, but there is no question we are causing climate change. People who argue otherwise are blinding themselves for their own convenience.

Comment: Re:But (Score 1) 464

by superposed (#36660046) Attached to: China's Coal Power Plants Mask Climate Change

Doesn't this give us a steer towards a short-term fix? ... we could offset warming with some floating mirrors [or] tinfoil kites [or] pump some more dust up there.

The problem with these geoengineering approaches is that a ton of CO2 added to the atmosphere will continue to warm the planet for thousands, of years. On the other hand, these solutions are temporary, e.g., aerosols are washed out of the atmosphere within a few months or years.

You didn't suggest this, but if we continue emitting CO2 and try to mask the effect with aerosols, we will need to add more and more aerosols every year, until it becomes economically unfeasible and environmentally devastating. You don't want to live in a world where we pump enough aerosols into the atmosphere to mask 700 ppm CO2, and they all come back as acid precipitation.

The trouble with the rat-race is that even if you win, you're still a rat. -- Lily Tomlin