Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror

Comment Re:Michelson-Morley were wrong. Ether exists (Score 1) 311

No, they are identical in the type of instrument they used, not in what they were trying to measure. MM were trying to find a "preferred frame", to see if the speed of light varied with the orientation (and motion around the sun) of the detector. They would not have found that no matter what the qualities of their detector were because it does not exist, and if they had detected gravitational waves, they would have been considered noise for the purpose of that experiment. You're saying that two different uses of an interferometer constitute the same experiment. You are very much mistaken.

Comment Re:Michelson-Morley were wrong. Ether exists (Score 1) 311

They weren't going to find gravity waves because they weren't looking for gravity waves. Gravity waves would have been considered noise in their experiment, even if they had an arbitrarily precise machine, because that was not the thing they were trying to measure. That was the whole point of having a rotating interferometer. They were trying to detect a "preferred frame", and they would not have detected one no matter how precise their machine was because there is no such animal.

Comment Re:Michelson-Morley were wrong. Ether exists (Score 2) 311

No, the MM experiment was measuring the speed of light in different orientations. Just because both used interferometers does not mean that they are measuring the same thing. If the MM experiment were arbitrarily more precise they would not have detected any change in the speed of light regardless of the orientation of their device, and spacetime fluctuations would have been dismissed as noise, and not particularly significant noise at that.

You are deeply confused about pre-Einsteinian theories of light and the purpose and significance of the MM experiment.

Comment Systemd and SysV (Score 1) 199

It's not just systemd that is destroying SysV. It's also Solaris, OS X, PC-BSD, and FreeBSD -- we can probably say well over 90% of the major Unix platforms. For better or worse, OpenRC is also making many of the same choices as systemd, including heavy dependence on C libraries, dependency resolution, parallel startup, and cgroup support. The critical failure of SysV init is the pidfile. It was always a bad hack — perhaps necessary for cross-platform support in a world without real process tracking, but now there isn't a hell of a lot of competition in any given market segment, and cross-platform support is being seen as less important than being able to accurately manage services. Yes, pidfiles almost always match the service they are supposed to, but this is not something that should ever have been left to userland. Similarly, daemonizing a process should never have been left up to script writers, given that glibc doesn't even do it correctly.

So now we're putting process tracking back into the kernel and it's a breaking change. If cgroups had been part of the POSIX standard years ago, systemd would have attracted no more attention than upstart when it was released. It *is* init, it has a superset of the same features, only with an event-driven model, and a slightly more sensible approach to dependency resolution than upstart. You may not have reached the limits of inittab, but other people with different use-cases have, and there's nothing in particular wrong with either case. The argument with systemd isn't an argument about how best to manage services, it's about technical debt so entrenched that people think that's the way it's supposed to be.

Comment Nuclear Weapon Size (Score 1) 240

There are limits to how much you can miniaturize a nuclear weapon. The term "critical mass" is key: you need a certain amount of fissionable material in order to sustain the chain reaction. This varies for different isotopes, and can be influenced by the level of explosive compression that you are able to achieve. This paper puts a lower bound for U235 and Pu at 6.5kg and 2kg respectively and discusses some of the compression methods. The smallest warhead made (W54) weighed about 23kg.

Comment Re:Summaries, how do they work? (Score 1, Informative) 86

Apologies, I had thought that the links were sufficiently informative, especially given that we had an article on the same subject earlier this week. I've never used Docker personally, and have a fairly loose grasp of what it entails, but the idea of application containers has been around for something like 20 years -- BSD Jails, lxc, systemd-nspawn, Solaris zones, and whatever that CoreBoot based one is -- there was an article about it on Thursday. Half of the comments are saying how Docker is a dressed-up version of an old solved problem. With respect, I think this one is on you, although your point in general stands.

Submission + - Docker Images To Be Based On Alpine Linux (brianchristner.io)

Tenebrousedge writes: Docker container sizes continue a race to the bottom with a couple of environments weighing in at less than 10MB. Following on the heels of this week's story regarding small images based on Alpine Linux, it appears that the official Docker images will be moving from Debian/Ubuntu to Alpine Linux in the near future. How low will they go?

Comment This is not Star Trek (Score 1) 310

A Ship that you can point in a direction and go.

This is not Star Trek. We do not have reactionless drives and unless there's a wild loophole in thermodynamics, we likely will. You are always going to be held back by the rocket equation.

A Ship with a multi mega watt power source

Ludicrous. Why would you even want to try to dissipate that much heat?

A Ship with several smaller vehicles for going to and from a planet

This is not Star Trek. There isn't going to be a one-size-fits-all solution for descending a gravity well. Hence why Curiosity's descent was so complicated -- and again, you run up against the rocket equation.

Comment Re:Open to Questions (Score 1) 1309

With regards to open sourcing Slashdot, I am not that completely opening the code would be best, and I do think that it would be a hard sell to C-levels. That said, some recent version of the code needs to be open, and development should be community-driven. The Unicode thing should have been a bug report/feature request. GitHub would be the obvious choice -- aside from a little issue with +1 spam, their issue/feature tracker integration is rather nice. I promise that ad-revenue-driven feature requests will receive mature consideration. For realio.

Comment Cloud9 and ChromeOS (Score 2) 168

I mostly use the exact setup you're talking about. I can't really speak to the "teamwork" aspects; for that I generally use CollabEdit, which is simpler for one-off collaboration. I got a Chromebook because I was planning on being in fairly impoverished areas in Central America for months or years, and I wanted a laptop that I was not going to worry about breaking. It works pretty well, all things considered. It's relatively simple to install a 'real' linux distro via crouton and get access to all the normal linux goodies. One specific advantage to ChromeOS is that it keeps track of what apps you have installed, and if you ever have to replace the unit, you can just sit at the new one, type your login info, and in about two minutes the new machine will have exactly the same stuff the old one did.

Having your development tools/files in the cloud means that they are inaccessible to you without an Internet connection, however, you don't need much of a net connection to be able to work: for Cloud9 there's an initial download of I believe about 1 MB for the editor, and actually editing code is possible down to a hundred bytes per second. Creating a local repo from a GitHub or Bitbucket repository is very simple, and each coding workspace gets its own little virtual machine, so you can install gems, run tests, and do anything you'd normally do. It also saves process state, so you can start (e.g.) pry, fool around with the interpreter, close the window, and the next time you start, pry will still be running. It actually saves quite a few brain cycles: you have less effort to figure out what you were doing the last time. Code completion and refactoring support exists, but is not what you would call world-class, more like SublimeEdit than intellij.

I have been using cloud9, but I have shopped around for various online editors at times, and so far I have not found any particularly compelling reasons to switch. I do not miss setting up a new chroot or container for a new project, or worrying about syncing code between workstations. Also note that there are online IDEs which can be run on your own private server (Cloud9 among them), for a hybrid approach, and of course there's nothing wrong with emacs over ssh if it comes down to it. At this point I doubt I would go back to a "real" IDE unless required to by an employer.

Comment Perfectly Secure Computer: unplugged (Score 1) 127

Linus did say that security is not the end-all be-all of Linux.

"Security in itself is useless. The upside is always somewhere else. The security is never the thing that you really care about."

Which is not to say that it's insecure; given that it runs on more devices than any other OS, any exploits would be huge. I'm not really sure how Windows security measures up these days, but I get the impression that the typical Windows install has a greater amount of exposed moving parts.

Comment Re:AGW Alternatives (Score 1) 176

Solar output is stable, at least over the modern era, and there is no connection between it and "the Pause" (that would actually be a crackpot theory). Long term shifts in Earth's climate have historically been the product of either volcanism or changes in Earth's orbit.

As for the "Pause", do you see how those lines in the graph you showed don't always match up? And yet they exhibit a high degree of correlation. Funny about that. Also, and I know that this has been explained to you, because it's explained to anyone that mentions it, "the Pause" is an artifact of picking what is now the fourth warmest year on record as your baseline. Picking any other baseline would show warming, and even with the cherry-picking, the hiatus in warming ended in 2013. Also note that 14/15 of the warmest years on record are since 2000 and that we haven't had a candidate for a coldest year on record in the last century: the 'new normal' is considerably warmer.

The idea that no one understands feedback mechanisms is as absurd as saying no one understands evolution. For an introduction to the topic, see chapter 8 of the IPCC Report[pdf]. It is admittedly pretty dense, but only 23 pages.

Do note that any further reference to a 19-year pause will not merit any response: lying with statistics is still lying, and if you don't understand why picking an extreme outlier as a baseline is dishonest then it's not worth my time explaining anything.

Slashdot Top Deals

If at first you don't succeed, you are running about average.

Working...