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Comment: The Usenet Physics FAQ did it better (Score 4, Informative) 213

by AdamHaun (#49791651) Attached to: Ways To Travel Faster Than Light Without Violating Relativity

For a more thorough and slightly more technical approach to the same subject, check out the Usenet Physics FAQ's article "Is Faster-Than-Light Travel or Communication Possible?". Here's the conclusion:

To begin with, it is rather difficult to define exactly what is really meant by FTL travel and FTL communication. Many things such as shadows can go FTL, but not in a useful way that can carry information.

There are several serious possibilities for real FTL which have been proposed in the scientific literature, but these always come with technical difficulties.

The Heisenberg Uncertainty Principle tends to stop the use of apparent FTL quantum effects for sending information or matter.

In general relativity there are potential means of FTL travel, but they may be impossible to make work. It is thought highly unlikely that engineers will be building space ships with FTL drives in the foreseeable future, if ever, but it is curious that theoretical physics as we presently understand it seems to leave the door open to the possibility.

FTL travel of the sort science fiction writers would like is almost certainly impossible. For physicists the interesting question is "why is it impossible and what can we learn from that?"

Comment: Re:This isn't a question (Score 1) 620

by AdamHaun (#49760153) Attached to: Ireland Votes Yes To Same-Sex Marriage

In the broadest scope I've never understood why there has to be laws concerning marriage. It's a private contract. There shouldn't be a question of can two people of the same sex get married - the question should be why we need to regulate this at all. If some regulation is found to be useful, what should it be? I'm not happy about "The State" getting that far into my business.

It's not the state getting into your "business", it's your business getting into the state. Marriage predates nation-states by millennia. And as a practical matter, I'm glad I didn't have to get a lawyer and sign a 500-page contract in order to get married, and I'm glad that other people don't need their own lawyer to go over such a contract in order to recognize my marriage.

Comment: Come on, Slashdot, at least get her name right! (Score 5, Interesting) 176

SurveyMonkey's CEO Dies While Vacationing With Wife Susan Sandberg

Dave Goldberg, the chief executive of SurveyMonkey and spouse of Facebook COO Sheryl K. Sandberg, died on Friday night.

Her name is Sheryl. It's fairly well-known. How do you screw this up when the correct name is in the first sentence of the summary?

Comment: Re:In before JERB-KILLITAXES AND REGULATIONZ (Score 1) 170

by AdamHaun (#49491037) Attached to: 2K, Australia's Last AAA Studio, Closes Its Doors

The US west coast is -10 GMT, the Australian east coast is +8 GMT. This means when someone gets to work in Sydney at 8:30 AM it's 3:30 PM yesterday in LA, if the head office is in Washington D.C. then all the execs have already gone home as it's 5:30 PM.

That's better than the U.S./India time difference.

Comment: Re:Broken thinking... (Score 1) 397

by AdamHaun (#49380845) Attached to: Why America's Obsession With STEM Education Is Dangerous

If you can master technical skills and complex math, overwhelming data suggests that you have also learned to read and think, and on the path to proving your competence have also managed to write clearly.

I used to think that way, but my whole working life so far has been the opposite experience. Many, many technically competent people simply don't put any effort into reading and writing. They might have passed the tests in school when they were being graded, but their emails, specs, and source code comments are not up to scratch. Very few people are *good* at writing, of course, but most people don't even proofread.

Comment: Re:There's only three plants. (Score 1) 417

by AdamHaun (#49322601) Attached to: How 'Virtual Water' Can Help Ease California's Drought

I was talking about the suggestion that California uses enough water to have a significant effect on Pacific sea levels. My back of the envelope estimate suggests that lowering the Pacific by one inch would take at least ten thousand times as much water as California uses in a year.

Comment: Re:Ever notice (Score 1) 438

by AdamHaun (#48462901) Attached to: How Intel and Micron May Finally Kill the Hard Disk Drive

Ever notice that NAND flash prices per megabyte have plummeted while EEPROM prices per kilobyte have remained high and then wondered how that could be rational?

Kilobyte-quantities of EEPROM are cheap enough that the package is probably a non-trivial part of the cost. The die cost is not the only lower bound on the price of a memory IC.

Comment: Re:100 year old survival knowledge in PDF files??? (Score 1) 272

by AdamHaun (#48264623) Attached to: A Library For Survival Knowledge

"Electrolytic capacitors leak, electrodes corrode"

none of those are present in a Kindle.

Those were generic examples. A better one for a mobile device might have been that the contacts on the charging port wears out. Based on the rest of your post I'm skeptical that you know anything about the components used to make Kindles, but I didn't design it so I won't speculate further.

I apologize for the LCD/E-Ink confusion. But it doesn't make a difference because neither of them are designed to last for 100 years. According to the company, they expect that "over 90% of E Ink displays will last more than 10 years with typical usage", where "typical usage" is defined as room temperature. Kindles are rated for operation between 0 - 35 C (32 - 95 F), and discussion on Amazon suggests that this is a real limitation. That range is similar to what LCDs can handle. I suspect that both are limited by a chemical breakdown process (which would happen exponentially faster at higher temperatures) but I don't know enough about displays to say for sure.

you cant get more "temperature extreme" than what [Voyager 1] experiences. and it has "electronics" in it.

If you think that a space probe is in any way comparable to a consumer e-reader, then I'm afraid you don't understand anything at all about electronics or engineering. Had you kept reading on Wikipedia, you might have found stuff like this:

The Flight Data Subsystem (FDS) and a single eight-track digital tape recorder (DTR) provide the data handling functions.

The digital control electronics of the Voyagers were based on RCA CD4000 radiation-hardened, silicon-on-sapphire (SOS) custom-made integrated circuit chips, combined with standard transistor-transistor logic (TTL) integrated circuits.

Electrical power is supplied by three MHW-RTG radioisotope thermoelectric generators (RTGs). They are powered by plutonium-238 ... and provided approximately 470 W at 30 volts DC when the spacecraft was launched. Plutonium-238 decays with a half-life of 87.74 years ... Additionally, the thermocouples that convert heat into electricity also degrade, reducing available power below this calculated level. By 7 October 2011 the power generated by Voyager 1 and Voyager 2 had dropped to 267.9 W and 269.2 W respectively, about 57% of the power at launch ... As the electrical power decreases, spacecraft loads must be turned off, eliminating some capabilities.

Voyager-1 was designed from the ground up for reliability in a hostile environment. I can't find a price for the hardware itself, but you can bet it was a more than $100, probably by several zeros. And even so, it's looking like the power supply will fail before it turns 100. A Kindle is nowhere near that level of reliability. It doesn't need it and nobody wants to pay for it.

Comment: Re:100 year old survival knowledge in PDF files??? (Score 1) 272

by AdamHaun (#48253751) Attached to: A Library For Survival Knowledge

If cared for a kindle DX can last 100 years.

On what do you base that statement? Consumer-grade electronic devices are not designed to last that long. Electrolytic capacitors leak, electrodes corrode, copper in IC traces migrates and shorts out, batteries wear out. I don't know about LCDs, but I'm sure they have long-term failure modes too, especially if they're exposed to sunlight. The whole device will be exposed to temperature extremes due to the lack of air conditioning in a survival situation. I'll buy 20-30 years. But 100? No way.

Tomorrow's computers some time next month. -- DEC

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