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Submission + - Another large Black hole in "our" Galaxy (arxiv.org)

RockDoctor writes: A recent paper on ArXiv reports a novel idea about the central regions of "our" galaxy.

Remember the hoopla a few years ago about radio-astronomical observations producing an "image" of our central black hole — or rather, an image of the accretion disc around the black hole — long designated by astronomers as "Sagittarius A*" (or SGR-A*)? If you remember the image published then, one thing should be striking — it's not very symmetrical. If you think about viewing a spinning object, then you'd expect to see something with a "mirror" symmetry plane where we would see the rotation axis (if someone had marked it). If anything, that published image has three bright spots on a fainter ring. And the spots are not even approximately the same brightness.

This paper suggests that the image we see is the result of the light (radio waves) from SGR-A* being "lensed" by another black hole, near (but not quite on) the line of sight between SGR-A* and us. By various modelling approaches, they then refine this idea to a "best-fit" of a black hole with mass around 1000 times the Sun, orbiting between the distance of the closest-observed star to SGR-A* ("S2" — most imaginative name, ever!), and around 10 times that distance. That's far enough to make a strong interaction with "S2" unlikely within the lifetime of S2 before it's accretion onto SGR-A*.)

The region around SGR-A* is crowded. Within 25 parsecs (~80 light years, the distance to Regulus [in the constellation Leo] or Merak [in the Great Bear]) there is around 4 times more mass in several millions of "normal" stars than in the SGR-A* black hole. Finding a large (not "super massive") black hole in such a concentration of matter shouldn't surprise anyone.

This proposed black hole is larger than anything which has been detected by gravitational waves (yet) ; but not immensely larger — only a factor of 15 or so. (The authors also anticipate the "what about these big black holes spiralling together?" question : quote "and the amplitude of gravitational waves generated by the binary black holes is negligible.")

Being so close to SGR-A*, the proposed black hole is likely to be moving rapidly across our line of sight. At the distance of "S2" it's orbital period would be around 26 years (but the "new" black hole is probably further out than than that). Which might be an explanation for some of the variability and "flickering" reported for SGR-A* ever since it's discovery.

As always, more observations are needed. Which, for SGR-A* are frequently being taken, so improving (or ruling out) this explanation should happen fairly quickly. But it's a very interesting, and fun, idea.

Submission + - Surado, formerly Slashdot Japan, is closing at the end of the month. (srad.jp) 1

AmiMoJo writes: Slashdot Japan was launched on May 28, 2001. On 2025/03/31, it will finally close. Since starting the site separated from the main Slashdot one, and eventually rebranded as "Surado", which was it's Japanese nickname.

Last year the site stopped posting new stories, and was subsequently unable to find a buyer. In a final story announcing the end, many users expressed their sadness and gratitude for all the years of service.

Comment Re: Google did a study about this (Score 1) 220

You honestly believe that existing C++ code out in the wild today would most likely pass a borrow checker with just some extra ownership info tacked on?

Nope. Nope. LOL! Nope.

If you can get away with just a major refactor, you'd be lucky. All other cases, the entire architecture would likely need to be vetted, resulting effectively in a rewrite. The only things preserved would be auxiliary modules and perhaps the project name.

Comment Re: This is weak of them (Score 5, Insightful) 68

That might work if Firefox still had 30% market share. Truth be damned, folks will simply say the site works in Chrome, so Firefox will be blamed. And even if they recognize that Firefox isn't at fault, it's easier to tell people to use Chrome than to get all those broken web sites to patch.

Rock. Hard place. Pragmatism.

Comment Re:Time for Faraday shielding and spectrum analyze (Score 5, Interesting) 84

Cheating between grandmasters in an over-the-board game doesn't really need a system requiring electronics. Kasparov once said many years ago, that all he would need to get an edge is to know that there is a devastating move to find. Once you know that such a move exists, you can concentrate your time (chess at this level is really a game of time management) on the key move. The grandmaster can find the solution themselves from there. Communicating that type of information is very cheap and easy. It's just one bit of information - normal move vs critical move. It could be done very effectively by someone sat in the audience holding a water bottle. Hold it in the left hand normally, and then hold it in the right hand to indicate the critical move. It sounds ridiculous but this is something that has worried grandmasters for decades. In the 1978 World Championship, Korchnoi objected to tubs of yogurt being bought out for his opponent Karpov. It was eventually agreed that he could have the same flavoured yogurt bought out at the same time every match, thereby eliminating any information being transmitted by flavour or time. Once you realise the possibilities of signalling in this way, it's very easy to see how a player can be driven to distraction or paranoia; and I suppose in extreme cases, madness. "If it's not the tub of yogurt or the bottle of water, maybe it's the flicking of the lights, or the cough in the background or the sound of aeroplanes flying overhead..." The possibilities are almost endless. So while there's no evidence of it happening in Niemann vs Carlsen, cheating (for a limited definition of cheating) in live events is not as difficult as it first appears. My own opinion is that Carlsen is simply paranoid but given Niemann's admitted history, it's not completely unjustified.

Comment Re: Rust garbage (Score 0) 157

What you've been describing, I call "lifelong geek syndrome". You've known it for so long, you've forgotten what it's like not to know it. You've invested so much time learning the specific tools of your trade, you lean toward disdain for those reluctant to follow the same path.

I started learning C three decades ago. C++ about 7 or 8 years later. And frankly, compared to today they were a mess. Still are a mess, but Stockholm Syndrome and experience make it somewhat manageable. Most of computing is like this. You and I have spent a great deal of time learning how to avoid use after free, to avoid memory leaks, adopted unique_ptr instead of bare pointers whenever possible, honing our craft, debugging obscure race conditions in production, finding tools to shore up the gaping holes in C and C++'s memory safety model, etc.

But to claim that everyone of any experience level should know to adopt, configure, and use the baroque array of disparate tools to help C and C++ be less of a collective dumpster fire is nonsense. If software engineers built bridges and airplanes, death would abound.

That's like a great writer claiming that English is an elegant language with no possibility of substantial improvement.

There are several sorely missed features in C++ that everyone agrees would be great ideas and simply things were it not for breaking ABI compatibility and 30+ years of legacy.

Rust is not perfect (and not even necessarily the best replacement for C when looking at alternatives like Zig), but it is by far the closest I have seen to a C++ with unique_ptr/shared_ptr effectively being mandatory and enforced by the compiler, sane and consistent module support, typesafe macros (c'mon, the preprocessor is a dumpster fire all on its own), a simpler template metaprogramming model, comprehensive dependency management, forbidding diamond inheritance patterns, cleaner functional programming options, etc.

You are an expert in the C and C++ tool domain, but that's not an industry goal. C and C++ are not and have never been the goal. No language is. The goal is getting good software released, fewer security problems, and faster release times. That's it.

If someone starting out their career today by following your advice that C, C++, a pile of different add-on tools, and years of experience learning to avoid 30-40 years of legacy cruft, they are doing themselves and the industry a gross disservice.

Go should displace Java to improve the state of things precisely because it doesn't consume RAM like it's going out of style and is a much better fit for smaller, composable functions in the cloud. Rust should replace C++ for new systems level development whenever possible precisely because most folks with less than 30-40 years of experience in the industry will produce safer, more secure, and more maintainable code by virtue of learning from and adapting the lessons of those 30-40 years of mistakes.

But by all means, try to defend #define, #ifndef, and null-terminated character strings as some sort of natural virtue or how things like the iostream were paragons of modern design rather than poorly conceived and byzantine minefields.

Comment Re: Career DB Expert Here...you're very incorrect (Score 1) 53

Most major relational databases today have an indexable JSON data type. You don't need a thousand tables with hundreds of foreign keys.

MongoDB is a one-hit wonder whose fifteen minutes were up quite a while ago. (I also find it difficult to forgive MongoDB for the numerous data integrity bugs they've had over the years.)

Comment Re: In any sane world... (Score 1) 53

There's definitely use cases for NoSQL. That doesn't necessarily mean that all NoSQL offerings are worthwhile. I for one like DynamoDB and Redis for certain specific use cases. MongoDB on the other hand can kick rocks. I'd rather use Postgres with indexed jsonb columns over MongoDB every day of the week and twice on Sundays.

Because one day, you're gonna need something beyond JSON, and the MongoDB dev will not be happy on that day. They'll make excuses, wrap their data in makeshift JSON, tie their code in spaghetti knots, and deny to their last breath that anything has indeed gone horribly wrong.

And all because they simply refused to properly learn SQL and use the various highly tuned engines that implement it.

Comment Re: In any sane world... (Score 1) 53

You say that like relational and transactional (aka OLTP) are synonymous. They are not.

Redshift: column-oriented analytic RELATIONAL database (OLAP)

TimescaleDB: time series RELATIONAL database

YugabyteDB: distributed multi-master with horizontal scaling

And those are just some of the PostgreSQL-compatible offerings, hardly an exhaustive list of all SQL-compatible offerings out there from multiple vendors.

Comment Re: Pathetic attempt to distraction heats up (Score 4, Informative) 343

Abortion makes up ~3% of PP's services, it is not in any way an outsized profit center for PP, and no government funding goes toward abortion since their budget is specifically bifurcated to avoid it by federal law.

But none of the right wing news sources you follow reported those inconvenient facts, have they? Nor do they discuss where the other 97% of womens care will come from if PP is shut down. It's partisan political theater, and you fell for it.

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