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Comment Re:Cool! (Score 1) 370

I've never found a good simple explanation. The basic idea is:


Arrows show motion, close to the speed of light.

A sends to B FTL. In the reference frame of C and D this seems to go back in time.

B sends to D. This takes normal time, but B and D are close.

D sends to C. In the reference frame of A and B this seems to go back in time.

C sends to A. This takes normal time, but C and A are close.

In all reference frames, the message returns to A before it was sent, because everyone sees one big backwards-in-time hop.

Comment back from the dead? (Score 2) 37

> but Time described the acquisition as "game changing,"

Yeah, but they always say that. I think a marketing content creator would get fired if he failed to work "game changing" into the text somewhere.

> It remains to be seen what this will do for the future of MySpace ...

Who knows, maybe they'll re-skin it and make another go. Everyone wants to be the next Facebook.

Comment Re:Great (Score 2) 39

Gigabit LTE means that you'll be able to use up your entire high speed data quota in less than a minute, unless the carriers finally update their data pricing models.

How is it that we've ended up with $10 for 10Gb or less of data now for about ten years? In the meantime, we've gone from inefficient EDGE to unbelievably efficient LTE, with HSPA+ available now for, what, the last five years on most GSM family networks?

Yet the data prices haven't budged. The carriers have more bandwidth than ever, more efficient ways of using it than ever, but they still think they're running ancient EDGE or cdma2000 networks.

Easy - profits.

Remember just a few years ago when people paid 25 cents per text? And some even paid another 25 cents to RECEIVE a text? Same reason - it was a massive profit center

Then texting stopped being a thing - with many ways to avoid it been iMessages and IM apps and Hangouts etc which used much cheaper data instead of SMS. Plus competition made it such that carriers started offering unlimited text plans for $20 extra. And of course, they realized they had a new profit center - data. Even better, they charge by the kilo and not kibi, and for good measure, they toss in the OTA headers as well in the byte count.

So yeah, they're charging because they can because it makes them massive amounts of money. On the bright side, they do adopt the new technologies quickly in an attempt to make you overuse your data plan and pay even more outrageous overage charges.

Comment Re:Uh... let me think about it (Score 1) 472

Stupid truckers routinely follow their GPS up Tail of the Dragon.
They blindly drive right by the BIG YELLOW signs that basically say

"If you take your semi past this sign, you are an idiot, you will get stuck, please don't kill any motorcyclists with your stupidity."

They do get stuck way more often than that.

The solution is a truck specific GPS, which they do make What makes them special is they contain height information - before you start route planning, you enter in the height of your rig - the GPS will actually route with that information in mind - avoiding tunnels and routes where overpasses are too low to make it. (This may even entail taking an exit just to get back on the onramp).

The problem is, truck-specific GPSes are expensive and their map data even more so, so truckers often buy much cheaper car GPS units, or just use their phone's GPS system. None of which take height into account.

Of course, getting stuck and the subsequent tow, damage repair and other stuff suddenly makes the extra cost of a truck specific GPS a relative bargain.

Comment Re:Michelson-Morley were wrong. Ether exists (Score 2) 370

There's no difference between "change in speed of light", "change in distance", and "change in travel time for light". They're all the same thing. Don't both instruments detect very small changes in round-trip travel time for light, comparing one direction to the other?

Sure then 1880s apparatus wasn't going to detect gravity waves, but that's just a matter of sensitivity of the instrument. We still call an electron microscope a microscope.

Comment Re:Cool! (Score 1) 370

Oh stop this nonsense. Causality being broken with FTL speeds is one of the most annoying and most wrong thing ever when it comes to FTL.

Causality breaking is subtle. For a simple one-way trip, in your reference frame, nothing will seem wrong, but from another reference frame you may appear to go back in time. If you have two pairs of ansibles (FTL telephones), each pair moving relative to the other, it's possible to send a message round trip (FTL to your connection, normal space to another endpoint, FTL to its connection, back to you) in such a way that you receive it before you send it.

The circumstances needed to break causality are somewhat contrived, but it's possible.

This is also why silly things like long-distance sensors in sci-fi wouldn't work either because light is still based on photons.

So a warp drive moving a whole ship FTL is somehow more believable than some sort of wave or particle that travels FTL and can be bounced off things in front of you? I find tachyons easier to believe than warp drives, myself (much as I hated particle-of-the-week Trek episodes)

Comment Re:Uh... let me think about it (Score 5, Interesting) 472

TFS said

Could society's embrace of GPS be eroding our cognitive maps?

I delivered pizza for a few years, before GPS, and a few hours of taking orders will disabuse you of this naive notion that most people have "cognitive maps". Most people do not know where they live! They can't tell you the nearest major intersection. What they know is a sequence of steps to follow to get to their house.

"Turn left at the big tree. Turn right where the church was before it burned down. Turn left where Johnny was hit by that drunk drive last year. Look for the red house."

I'm only slightly exaggerating. I really do encourage everyone to use maps, to learn to change your "pathing" dynamically when conditions change, to know where you are not just the steps you took to get there. To quote the REM song: "Stand in the place where you work. Now face north. Think about direction; wonder why you haven't before ". Can you do it without looking anything up?

Comment Re:Cool! (Score 2) 370

I think you meant to say "Inconceivable? You keep using that word, but I don't think it means what you think it means".

Many fictional things are "conceivable", but in terms of real science, no one is going to take a casual "general relativity is totally broken" proposal seriously. General relativity has made more and better predictions (and more unexpected predictions) than just about anything. You can doubt any theory, but the more one has proven itself, the higher the bar to claim "but maybe it's totally wrong".

Every theory "might be wrong", but that's not a useful observation - it helps no one to point that out, much like complaining about the weather. "This might be true instead" is useful, but you have to explain everything the current theory is correct about too.

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