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Comment: Re:the mysterious "us" (Score 1) 178

by buchner.johannes (#48568057) Attached to: LA Mayor Proposes Earthquake Retrofits On Thousands of Buildings

The reason that the discussion isn't framed more to be about the safety of citizens is because it's assumed that people understand to have buildings not collapse in an earthquake is a generally good thing for everyone. Do you really have to have a discussion about how not having buildings collapse onto people inside them is a good thing or a bad thing? We even have some pretty good numbers of the costs associated with earthquakes, as they happen frequently enough in plenty of developed and undeveloped areas.

Isn't this a usual risk-cost calculation? Every building can decide whether the risk (probability times loss) is greater then the costs of avoiding the risk.

Comment: Re:Doesn't matter even if the publishers win... (Score 0) 681

by buchner.johannes (#48548897) Attached to: French Publishers Prepare Lawsuit Against Adblock Plus

I think the original post is delusional. People would still use AdBlock if ads were unobtrusive and static. They just want the content, just like they download movies without paying.

I am willing to bet that the fraction of AdBlock users that turn on the feature where some ads are allowed does not exceed 1%.

Humans want all of it, for free, and now. If they can't have it under those terms, blaming "stealing" on the providers is only half of the story.

Comment: Re:As far as I'm concerned, Pluto is still a plane (Score 2) 77

by buchner.johannes (#48543073) Attached to: Pluto-Bound Spacecraft Ends Hibernation To Start Mission

Sure, it might have originated in the Kuiper belt, but it isn't there any more.

That's not the point. The point is it has three moons of the same size as itself, and a lot of other debris. It's not dominating its environment.
You can choose: Either we have 8 planets, or you have to learn 19 names, and new ones every year or two. 9 is not an option anymore.

Anyways, I don't understand why "dwarf planet" was not made a subclass of "planets" along with "major planets" (where the others go). But no, it is "planets" and "minor planets", which are by definition not a "planet".

Comment: Re:Drake is Obtuse (Score 5, Informative) 334

by buchner.johannes (#48526085) Attached to: Aliens Are Probably Everywhere, Just Not Anywhere Nearby

I've always felt that the Drake Equation is not worthy of the term 'equation' since its just a simple probabilistic estimate from multiplying a ton of other probabilities and instances together.

It has a term on the left and a term on the right, and an equal sign in between. You can also see the Drake Equation as a Bayesian Network combined with a Poisson estimator for the mean (n*p).

Comment: Yes (Score 5, Informative) 238

by buchner.johannes (#48522671) Attached to: The Cost of the "S" In HTTPS

Caching: You can not cache Facebook for example, because the content is generated differently for every user. Youtube goes through great lengths to prohibit caching (e.g. with Squid) in the first place.
Proxying: You can proxy https just fine.
Firewalling: You can firewall https just fine.
Parental control: You can block websites just fine, either via DNS or IP.
I suspect they mean snooping for "copying that companies don't approve of" and "freedom fighters" here. And child pornography. It's kind of the point of HTTPS that it should be private. So yes, I can accept these costs.

Comment: I am Pluto? (Score 3, Interesting) 91

by buchner.johannes (#48521033) Attached to: Why Pluto Still Matters

But I think there’s something even more compelling at play here: most of us learn about Pluto as children, and as a child, Pluto reminded me of myself. It’s smaller than all the other planets, and it was the newest one to come along. To me, it represented all the undiscovered mysteries, all that was still unknown, and the hope that someday, it might matter more. I was actually rooting, as a kid, for Pluto to be bigger than Mercury, simply because I wanted it to be more important in some measurable way. And because it took longer to orbit the Sun than everything else, because it was different from all the other planets in practically every way, I truly believed it was special.

It’s been some thirty-odd years since I was that child, learning about Pluto for the first time, and in those same thirty-odd years, our estimation of the Solar System has grown to make it a larger, more well-known place. But in that same time, I’ve grown, too, and the most important lesson I’ve learned about Pluto—that I would have told my young self if I could—is this:

The fact that there are other things out there that are bigger, smarter, faster, stronger, or better than you, in any regard, in absolutely no way diminishes how special you are.

Compare that to Neil deGrasse Tyson:

Pluto is not a planet. GET OVER IT!

Maybe there is something to it and astronomy should incorporate peoples feelings in their classifications. Probably not.
But maybe in the communication? Actually i think they could have classified planets in "Big planets" and "Dwarf planets" instead of making "dwarf planets" not a subclass of "planets".

Comment: Re:I don't understand this ... (Score 3, Interesting) 184

Not all supermassive black holes are actively accreting. In fact, the fraction of time their accretion disks actually output massive amounts of radiation is ~10%, on patches of ~ hundred million years timescales.

A planetary system could form outside the center of the galaxy and travel close to the galactic center. You have to keep in mind that the distances between stars are enormous when compared to distances between planets. For example, our nearest star is 270 000 earth-sun distances (4 lightyears) away, while Jupiter is only 5 earth-sun distances from the Sun. So a "stripping" of planets, due to tidal forces, is extremely small, even when it comes close to the supermassive black hole in the center of the galaxy. It is true however that for the closest orbits, such as 120 earth-sun distances for S2 (S2 reaches speeds of 5000 km/s), this effect will be important. However, I suspect that while a single, quick swing-by will alter the orbits of planets (generally increasing ellipticity), that effect leads to the immediate destruction of the entire system. Normal planetary systems are also not stable systems. Changes in the orbits, interactions between planets, etc. are common; Only when stable oscillations are reached, the orbits remain the same for a few million years. So I suspect that the planets can re-arrange into a stable system (perhaps under ejection of one of the planets).

I think the changes are better if the system is a newly born star, where planetoids are still forming in a thick disk of gas and dust. Then, the partially destroyed disk can re-arrange quickly and form planets after swing-by. That would not necessarily be a problem for "spreading of life", if this process occurs e.g. via comets.

Comment: Re: Cubic gigaparsec ... (Score 4, Informative) 184

Unfortunately, space is not Euclidean on giga-parsec scales. Here, when talking about 5000 Gpc, they refer to a "comoving scale". That is a scale where the expansion of the universe has been divided out, so that e.g. the same number of galaxies remain in this box. So if you would place the atoms of the number of swimming pools you computed in the volume, they would be twice as dense at the largest distances, where the Universe was half the current size. Also, the largest distance within a 5000 Gpc^3 is 3200 Gpc (space is not Euclidean).

3500 Calories = 1 Food Pound

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