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Comment Re: Seriously?? (Score 2) 109

Simple use case. I mostly program in Fortran these days, but I often use Matlab for smaller things. What i do then, is instead of installing the 6GB of Matlab and all its toolboxes on my poor laptop, I have it installed on my work computer. I then ssh in, use 'matlab -nodesktop' to start an interpreter, and use it interactively. Every time i use a plotting command, the plot window pops up nearly instantly on my laptop. I'm not interested in using VNC, because first of all it would be inefficient to forward the entire desktop when i only want to see a few plot windows, and secondly my laptop doesn't have the same high screen resolution as my work computer. I only want to see the plots, and 'ssh -X' gives me that.

Comment Re:systemd has done more harm to Linux than SCO di (Score 4, Interesting) 169

I'm really confused as to why people hate systemd so much. Based on the negative reactions on Slashdot, I expected systemd to be unstable and bloated, and was thinking about perhaps migrating back to Gentoo or FreeBSD if the rumors were true. However, during the past year I've tested systemd with first Kubuntu 15.10 and then Arch Linux, I've had no trouble with it at all. On the contrary: the bootup was lightning-fast compared to previous systems, and everything just worked out of the box. Taking a look "under the hood", everything looked neat and clean as well: system services are configured through readable config files, that are much shorter and tidier than the typical SysV init scripts I've gotten used to. Most of the design choices make sense as well: I see no reason to keep daemons like e.g. initd and inetd separate on a modern system.

I've also read that systemd apparently saves a lot of work for e.g. the distribution maintainers and desktop environment programmers, in the first case since it is much easier to maintain a systemd service file than a SysV init script, and in the latter case because a lot of work that previously had to be redone for every Linux distribution can now be easily shared or ported between distributions. I don't think some homogeneity among base systems are a bad thing if it makes it much easier to make software work across distributions. For instance, almost nobody's complaining that using the Linux system with the GNU base system and X11 display server is bad because it makes the Linux ecosystem too homogeneous. Sure, you do have legitimate usecases for the BusyBox base system and framebuffer applications, but that's not the majority of Linux desktop systems. There will of course be legitimate usecases for other things than systemd, but I don't believe that holds for the majority of Linux desktop systems either.

The only criticism of systemd that I agree with, is that plaintext log files are a good thing. I think I understand the reason for having binary logs (making it easier to parse for programs and scripts without a making a regex-hell), but in that case it would be much saner if journald automatically transcribed the logs it generated to plaintext files as well. Apparently it is not too difficult to set this up yourself, but I still think human-readable logs should be default.

Comment Re:Why? (Score 5, Informative) 459

According to the Free State Project website, ``In a vote that ended in September 2003, FSP participants chose New Hampshire because it has a low state and local tax burden, a low level of dependence on federal spending, a citizen legislature where state house representatives have not raised their $100 per year salary since 1889, low crime levels, a dynamic economy with plenty of jobs and investment, and a general culture of individual responsibility, independence, and self-reliance.''

Comment Re:Cheap SOB's (Score 1) 182

This is not the researchers' fault, but rather the academic journals fault. These days, you mainly have two options when publishing a paper in a peer-reviewed journal: either the author has to pay a $1500-3000 processing fee to to publish it under a Creative Commons licence, or you get to publish it for free but all readers have to pay to access the article. Most universities make deals though, i.e. they pay a yearly fee to the journals so that the researchers and students at the institution can access what they want when they want without paying themselves.

The traditional model of most journals is the second one (readers pay), but the first model (authors pay) is becoming more and more popular with new journals like PLOS and Nature Scientific Reports. Older journals like Physical Review are also beginning to offer open access publishing options now. But in both cases, note that none of that money actually goes to researchers: either the authors pay $1500-3000 to publish, or the readers pay $30 to read, and all the reviewers work for free, so all of that money goes to the journal...

Comment Fortran + Vim (Score 1) 279

I currently do most of my programming in Fortran using Vim — and don't see any reason that this has to change during the next decade.

Note that I'm not one of the veterans that started with Fortran 77 a few decades ago; my first programming languages were Python, Matlab, and C++. But at some point, I was forced to learn the basics of Fortran in order to make a C++ wrapper for a library that I needed, and was so impressed with the modern versions of the language that I now do almost all my programming in it. For numerical work, you basically get the benefits of C++ (static typing, object orientation, high speed) and Matlab (matrices, complex numbers, array slicing, 'elemental' functions), combined with a large body of available legacy code from the last few decades that can be leveraged in your applications.

I expect that in ten years, if I'm still doing mainly numerical programming, I'll just be programming in a newer revision of Fortran using a newer version of Vim.

Comment Re:Interesting question for science oriented langs (Score 1) 304

Alternatively, you could also consider using multi-letter infix operators, such as c = a <u> b in your union example. This would have the benefit of being easy to type since it's only ASCII characters, but at the same time easy to pretty-print by just converting all instances of <u> to a unicode U+222A symbol using e.g. a regular expression. While this would make your language more original, it would likely be more user-friendly towards people used to other languages if you stuck to a function-like syntax c=union(a,b) though. This would also eliminate the problem figuring out operator precedence in large expressions.

Comment Re:Is mathematics invented or discovered? (Score 1) 189

Regarding the last point, about thinking very differently about imaginary numbers and quaternions, you might find this paper interesting; it is a readable and easily accessible introduction to the topic of geometric algebra, with an emphasis on its pedagogical applications in physics. This mathematical formalism goes back over a century to Grassmann and Clifford, and has been repopularized in physics by Hestenes. I believe some people are also using the formalism for computer graphics. The short version is that you can unify vectors, quaternions, and complex numbers into a single geometric formalism, if you just treat scalars, vectors, planes, and cubes all as first-class objects in a general geometric space, and that this leads to more intuitive geometric interpretations.

Comment Re: hoping the economic damage won't be too bad. (Score 1) 20

I wouldn't exactly call it "paranoia", as it's quite well-founded. My friend and I did a motorbike road trip through Vietnam about a year ago, and we didn't get the point of wearing those masks in public, so we just ignored the fact that all the locals were doing it. After a 2000 km trip over 11 days, I developed a tonsil infection, and my friend got a lung infection, so we both had to take antibiotics for the next two weeks. The doctor said that the reason was probably that we had been inhaling too much traffic dust; the dust creates lots of tiny tears in your throat and lungs, which leaves those parts of your body very vulnerable to infections. After that, I've been using a mask when driving through dry areas, and haven't gotten infected again so far :).

Comment Re:I still think Pluto is a planet (Score 1) 170

There are mathematically precise ways of defining the difference between planets and dwarf planets. If you check the table of planetary discriminants a little bit down the page, you see that there clearly appears to be two groups of planetoids in the list: those with a planetary discriminant of 10,000-1,000,000 which we call planets, and those with a planetary discriminant of 0.01-1.00 which we now call dwarf planets. Do you still disagree that these two groups, separated by four orders of magnitude in their planetary discriminants, deserve different names?

Comment Re:Explain it like I'm five (Score 2) 67

Sure, I'll give it a try. If you put two bar magnets next to each other, they tend to flip each other around so that they point in the same direction. Now try to picture an infinitely large universe, which is filled with an infinite number of tiny bar magnets. If all of these magnets pointed in the same direction, there wouldn't be much interesting going on; since all the tiny magnets are already aligned, they won't try to flip each other over, and the universe would be a stable place. (You could still have some fun by flipping a few magnets, and watching the ripples spread as a wave throughout the universe; but that's not what I'm gonna talk about now.)

But let us now consider a different scenario: in one end of the universe, all the magnets are pointing "up", while in the other end of the universe, all the magnets are pointing "down". By themselves, both these regions are stable, since there is nothing inherently "better" about pointing up than pointing down. However, somewhere in between these two far ends of the universe, there has to be a region where the magnets change from pointing up to pointing down; and this is a region of higher energy, since you have all these tiny magnets which are constantly fighting among themselves about which way to point, and constantly trying to flip each other over. This is called a "domain wall" in the case of magnetism, which is an example of a "topological defect". This domain wall can be moved and twisted by flipping a finite number of magnets in the vicinty of the domain wall; but you can't truly get rid of it without flipping an infinite number of magnets throughout the universe, which would end up requiring an infinite amount of energy.

In some quantum field theories, you get analogous situations where a theory has multiple stable "vacuum solutions". If the universe contains fields like that, we would then have two possible scenarios: (i) the entire universe has the same vacuum state (corresponding to all the magnets pointing in the same direction); or (ii) the universe could in principle consist of different stable regions with different vacuum states, with an unstable region called a "topological defect" inbetween, where the different vacua fight for dominance.

Comment Re:Hmm, says here: (Score 1) 249

In general relativity, gravitation is not modeled as a direct force between massive objects. Instead, any form of energy density (mass according to E=mc^2, electromagnetic fields, and so on) causes spacetime to curve, and this curvature of spacetime then alters the motion of particles through spacetime. I've always liked the summary "energy tells spacetime how to bend, and spacetime tells matter how to move".

So yes, it is true that electromagnetic fields also act as a source of gravity. However, you'll need some really crazy field configurations before that effect starts becoming comparable to the gravitation from stars and planets though. For a very rough estimate of the sizes involved, you can try setting the volumetric energy density of an electric field (vacuum permittivity)*(electric field)^2/2 equal to the mean energy density (earth mass)c^2/(earth volume) of the earth, which leads to the result 10^16 V/m for the electric field. This is roughly 10^10 times the electric breakdown voltage of air at standard temperature and pressure...

Comment Re: Old saying (Score 4, Informative) 249

wouldn't that make the concept of time fundamentally flawed?

In any given reference frame, time is a well-defined quantity. The fundamentally flawed concept here is the idea of some kind of universal time that passes at the same rate everywhere in the universe, because relativity tells us that the observed passage of time is affected by things like velocity, acceleration, and gravitation, and therefore varies between different reference frames -- and we have no objective reason to say that any particular reference frame in the universe is inherently superior.

So while the atomic clock might measure the local passage of time with near perfect accuracy in the reference frame where we place it, the results will just be approximate in any other reference frame.

Comment Re:How on earth (Score 1) 128

I can imagine a couple of applications of these transistors though...

Many numerical simulations require repeated random sampling of some process, and then combine the results in the end. If you're averaging some billion simulations, the result should be quite robust to fluctuations in the results of each simulation. Thus it might well be worth it to use 10 billion unreliable transistors instead of 1 billion reliable transistors, if they cost the same.

Another application could be to generate random numbers. Let's say that you have a pseudorandom number generator with periodicity N, and your unreliable transistors makes the algorithm do a random jump after an average of N/100 numbers. Wouldn't that be "random enough" for more applications than just the pseudorandom number generator itself?

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