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Comment: Re:why do people think FTL... (Score 1) 134

by david_thornley (#48685361) Attached to: New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle

Why do people think FTL allows for backwards time travel? It's called Special Relativity, and is much more convincing than people's general ideas. p> Suppose you're in a spaceship traveling at a speed relative to another spaceship such that time dilation is 2, meaning that for each of you time appears to pass at half speed for the other one. When you meet, you exchange ansible (instantaneous communicator) settings. An hour after, you put your coffee cup on the edge of the console, and it falls and breaks. You send a message to the other guy. You observe him getting it when, from his point of view, it's half an hour after meeting. He relays the message back, and observes you getting it when you are fifteen minutes from the meeting, and the message has therefore returned forty-five minutes before you sent it.

In order to argue with this, you need to at least understand it. You need to understand that "forward" and "back" are not determinate with any FTL phenomenon. (There is an objective forward and back as long as things stay under the speed of light. FTL is "sideways", using this classification, and has no "forward" or "back".)

Comment: Re:Sigh.. (Score 1) 134

by david_thornley (#48685263) Attached to: New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle

Special relativity (a very well-tested theory) also shows that faster-than-light travel or information transfer allows travel or information transfer back in time. (The converse is obviously true: if you take five years to go to Alpha Centauri, and then go back four years, you've traveled FTL.)

Lots of people are rather attached to the idea of one-way time and having non-paradoxical causality, which means they don't want it to be possible to send information faster than light.

Comment: Re:who cares how many children (Score 1) 260

by david_thornley (#48685107) Attached to: AirAsia Flight Goes Missing Between Indonesia and SIngapore

The wording in TFS implies that adults don't matter at all. If it had said something like "5 crew and 116 passengers, including sixteen children and a baby", that'd be cool. It would acknowledge all lives lost, with some additional description for human interest.

I haven't looked at news reports, so I don't know if TFS is unusually egregious here (not unusual for /., really).

Comment: Re:Does he stand a chance? (Score 1) 162

by david_thornley (#48663305) Attached to: 'Citizenfour' Producers Sued Over Edward Snowden Leaks

There is some logic here, but it's tricky and thin.

If information is released publicly, there's still reasons to keep it classified. Once it's unclassified, anybody with a FOIA request can verify it, but if it's still classified there's at least some plausible deniability. The government can claim that some of the documents don't really mean what they say, or were faked, or whatever. It may not apply in any particular situation, but somebody has to make that determination, and until formally declassified it's still classified.

It's easier and simpler to tell people not to read classified information than to tell them not to read classified information except from publicly available sources. It makes investigation easier: if you know that document X should not be in the browser cache, it's easier if you don't have to figure out where it came from.

Security clearances are not mandated except if you want a certain job, but are rather voluntary, and in this case there's some reason to have strict rules that are clear and don't involve judgment.

Comment: Re:I had this problem, then I got f.lux. (Score 1) 178

by david_thornley (#48662997) Attached to: Study: Light-Emitting Screens Before Bedtime Disrupt Sleep

When things are light, and so there is less of a need to rely on the monitor's brightness

I don't get this. You don't see an image on a monitor through reflected light, you see it from the light emitted by the monitor. I need more light when it's bright out, because it has to outshine the ambient light to be seen.

Comment: Re:What about... (Score 1) 178

by david_thornley (#48662947) Attached to: Study: Light-Emitting Screens Before Bedtime Disrupt Sleep

I've tried more technical stuff on my eInk reader, and it doesn't work. It's great for reading something from start to finish, as long as I don't care about illustrations, and I read a whole lot of things that way, including anything I'd want to read around bedtime. It's lousy with PDF files, since it isn't big enough for most of them, and Calibre is iffy on converting PDF to ePub.

Comment: Re:Rape comes in many forms : sexual, economic, et (Score 1) 188

by david_thornley (#48661671) Attached to: Uber Pushing For Patent On Surge Pricing

If somebody sticks a penis into you without your consent, it's rape. When somebody removes money from your wallet without consent, that's robbery. The key words here are "consent".

Nobody is making you buy a ride from Uber, and nobody's going to guarantee to provide a service with a significant marginal cost at whatever money you think is appropriate.

Comment: Re:Detect price gouging (Score 1) 188

by david_thornley (#48661641) Attached to: Uber Pushing For Patent On Surge Pricing

I can pay for the right to use HOV lanes on at least one freeway around here, so I can go in a faster lane than people who don't (and who don't carpool).

Grocery stores don't conduct auctions because their customers would hate it, and would go to other grocery stores.

If you get into an accident, you will get emergency care triaged by seriousness of injury. Any care after that, in the US, depends on ability to pay.

People tend to hate surge pricing, but it is economically efficient.

Comment: Re:Detect price gouging (Score 1) 188

by david_thornley (#48661595) Attached to: Uber Pushing For Patent On Surge Pricing

Isn't this more of a reason to make sure everybody gets enough money to afford a Uber ride than to ban surge pricing? Since surge pricing gets more Uber cars on the road, it gets people to their destinations faster on the average.

Most people who can afford Uber in the first place can manage surge pricing if they really need to, and with surge pricing they'll get a ride faster that way. Obviously, some people have to watch their dollars closely, but they aren't going to be using Uber much anyway.

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