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Comment Re:Travelling at 20% of the speed of light (Score 1) 189

I'm not sure we have a transmitter though that we can blast over the distance and still be captured, so we can add a few more years to that.

In order for us to be able to measure a signal from a probe, it would have to be not just bright enough for us to detect it, it would also have to be bright enough to discernably change the light we get from the star.

This page says that it is possible to outshine a star for brief moments (few nanoseconds) using lasers: https://www.princeton.edu/~wil...

I've done some back of the envelope calculations to verify that. And while its totally wrong that one 10 000 th of the output of a star is 4 joules per ns, it should still be possible to build a laser that outshines proxima centauri.

According to wikipedia, proxima centauri has a luminosity of 0.0017 times the luminosity of the sun, which is 382.8 * 10^24 Watts. So it has 6.5 * 10^23 Watts of luminosity.

Let's assume the laser has a beam divergence of .1 millirad.
This page has an example for a red (1064 nm) laser, but we want to shoot a blue one as proxima centauri is mostly red so doesn't have much blue luminosity: https://www.rp-photonics.com/b...

On .1 milirad, the star would emit approx 2.5*10^-10 of its total output (2.2*10^-10 = (.1/(1000*pi*2)^2). That would mean 1.6*^10^14 Watts for proxima centauri.

If you say that .1% of the star's total emitted light is blue at the specific wavelength you are sending, you have to divide by 1000.

Per nanosecond, it would be 163 joule. Theoretically possible, but question is whether you can build a sender and receiver (and get the sender into the right place).

Comment Re:Reminds me of a crazy, hot girlfriend (Score 5, Insightful) 309

You get an economic benefit from mistreating and neglecting her. If she freaks out, you don't have to pay for the outcome, the federals do. Just look at japan, where tepco now got money from the government to clean up the fukushima mess. And in this case, the feds have to pay as well.

So if there is no consequence to fear, why shouldn't you mistreat and neglect her?

Comment Re:It's not Linux (Score 1) 306

Yes, the high percentage of devs on linux/mac computers has scared microsoft (if trends continue, the next stack overflow developer survey will have less than 50% of devs on windows). Even though they do annoy customers, they still cling to their monopoly, as it allows them to annoy customers.

They didn't do it because they liked linux. They did it to convince devs to move from linux to windows, because now the devs can enjoy both the features of the linux world and the features of the windows world.

Comment Re:Microsoft's underestimating their legacy base (Score 1) 399

It should be a lesson that if you build on proprietary technologies, you might end up in a mess if the owner of the technology abandons it in favor of a better alternative. Use open non proprietary technologies, they live much much longer. Take TCP for example, everyone still uses it. There were probably tons of proprietary competitors to TCP, but all of them died because in the long (and I mean decades) run, open solutions win.

Comment Re:Did KDE survive KDE3-KDE4? (Score 1) 508

Three KDE applications I really like (and use, although I don't do much profiling so not using kcachegrind that often):

* KDE connect
* Kcachegrind
* Kate

Yes, there are totally shitty ones I don't like for example amarok. But some of the KDE programs are really good and useful etc.

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