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Comment: Re:C is not what people think it means (Score 2) 140

by sconeu (#49791677) Attached to: Ways To Travel Faster Than Light Without Violating Relativity

Bzzzt!!! Thank you for playing. Here's your lovely parting gift.

Let's rephrase... as an outside observer sees you go faster you get compressed to THEM.

From your frame of reference, the outside world is going faster and is compressed, so the distance to the star that is 100 ly away gets compressed by the gamma coefficient.

Comment: Re:oh the Irony (Score 4, Informative) 294

by Shakrai (#49791459) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

DC has very rapid power loss over any kind of distance.

No it doesn't. Losses are related to current, not AC vs. DC. A higher current in the same sized conductor equates to higher loss. You can get around this by raising the voltage (traditionally easier with AC), thus transferring the same amount of energy with less current, or you can increase the size of the conductor. DC can actually transfer more energy than AC on a similar sized conductor because it doesn't have to deal with skin effect.

I could link all of these terms to applicable articles for you but I'm feeling lazy and this is all common knowledge stuff anyway.

Comment: Re:Someone claim (C) on something oracle depend on (Score 2) 157

The Open Group claims the copyright on the POSIX specifications. If APIs can be copyrighted and this copyright includes all implementations, then it would be problematic for all open source *NIX systems. Of course, they might decide to provide a license that's valid for everyone except Oracle (though writing such a license in a way that's GPL compatible would be very hard, so glibc might be in trouble).

Comment: Re:Important Question: WHICH DC? (Score 1) 294

by TheRaven64 (#49791213) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage
The thing that killed DC in the war of the currents was that step up and step down transformers for AC are easy and cheap to build, but doing the same thing for DC caused a lot more loss (one of the simplest ways of doing it was to convert to AC, do the voltage change, and then convert back to DC). For long hauls on the grid, you want a much higher voltage than in houses. Now, however, it's relatively cheap (both in terms of convertors and in terms of loss) to produce DC-DC converters. USB-C supports 5V (up to 2A), 12V (1.5-5A) and 20V (3-5A). It's fairly easy to imagine 48V between rooms and then a converter in the sockets able to provide USB voltages. You wouldn't want to run a heater or a vacuum cleaner from it, but it would be nice for a lot of consumer electronics.

Comment: Re:Impractical (Score 2) 294

by TheRaven64 (#49791099) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage
We're not talking grid back-haul though, we're talking a few tens of metres maximum within a house. I've wondered for a while if it would be more efficient to have moderately high voltage DC room-to-room and then low-voltage DC in rooms. Given the number of things in my house that would prefer a DC supply and so end up with (cheap and inefficient) AC to DC convertors per plug (and especially if you use LED lighting), it seems like it ought to be a win. And now seems like a good time to do it, as USB-C is a consumer connector that can provide up to 100W via something that's designed to be very cheap to produce in the lower power variations.

Comment: Re:Oh man (Score 1) 118

by TheRaven64 (#49789459) Attached to: Scientists Reverse Aging In Human Cell Lines
Top 10% probably. Take a look at a global rich list calculator. You can live very comfortably in a western country with 9% of the world's population being richer than you. If you're in some parts of central or eastern Europe, or a few parts of south-east Asia then you may be near the bottom of the top 20% and still living very comfortably. The '1%' that people talk about in the USA are well in the top 0.1% globally, but 'the 1%' makes a better soundbite than 'the 0.1%'.

Comment: Re:That poor man (Score 2) 257

I find it hard to consider anyone who owns a house (even with a mortgage), especially in one of the places with the highest property prices in the world, poor. This scheme seems very odd, because the poorest residents of California are renting, they don't own houses (well, the poorest are homeless), who can't just stick solar panels on top of a house that they're renting.

Comment: Re: Not pointless... (Score 1) 454

by Shakrai (#49787421) Attached to: D.C. Police Detonate Man's 'Suspicious' Pressure Cooker

Bomb squads don't "investigate" items that might be bombs. They safely dispose of them. Are you seriously going to value a $30 pressure cooker over someone's life? If the authorities were wrong they should (and usually do, FYI) reimburse the property owner. No piece of property is worth taking a chance on someone's life.

Comment: Re:a microscopic black hole won't hurt you (Score 1) 142

by sconeu (#49786673) Attached to: Prospects and Limits For the LHC's Capabilities To Test String Theory

Turns out that minimum-size black hole you'll need to destroy Earth is roughly the mass of Mt Everest.

This must be why evil mad scientists are always found underneath large volcanoes. Everything is clear to me now.

Well... that, and the unlimited geothermal power, and, of course, the availability of lava pools for unnecessarily slow dipping mechanisms!

Comment: Re:Like the companion app (Score 1) 65

by TheRaven64 (#49781067) Attached to: Microsoft Bringing Cortana To iOS, Android
Apple used to ship iSync with OS X, which could sync calendars and contacts with a wide variety of phones via bluetooth or a cable. It also had a nice plug-in architecture for adding new sync clients (and new kinds of data to sync). They also had some Bluetooth integration with the address book app, so when someone called your phone you'd get a pop-up on the screen of who it was and could send SMS directly from the address book. All of these features disappeared with the first OS X release after the iPhone and were replaced with cloud-base syncing that only worked with the iPhone.

Reactor error - core dumped!

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