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Comment: Re:Not really missing vinyl (Score 5, Informative) 433

by doublebackslash (#48595113) Attached to: Vinyl Record Pressing Plants Struggle To Keep Up With Demand

First I'd love to cite an extremely good video on this topic https://www.xiph.org/video/vid...

I'll try to distil down the relevant portion here.
Nyquist showed us that a bandwidth limited signal sampled by a discrete time system can be reproduced perfectly using 2n samples per unit time where n is the bandwidth of the signal in hertz.

Perfectly isn't hyperbole here. That is mathematically shown.

The other half of digital audio is the accuracy of measurement of those discrete samples. “Bit depth” or bits. While we can reproduce a signal perfectly with perfect samples there is some noise that is added by imperfect sampling of a signal. This is mathematically identical to tape hiss and can be manipulated to less noticeable frequencies using a technique called dithering.

Digital audio can and does faithfully reproduce the original signal with levels of noise below human perception even at a meager 16 bit depth and 48KHz sampling rate (44.1 is also very popular but 48 allows easier low pass filter design).

The stair-steps don't come out of the audio jack, the signal is reproduced by the imaging circuit.
Fast attacks that fall “in-between” the samples are NOT delayed or lost since, again using Nyquist, the signal can be perfectly reproduced (and this is demonstrated directly in the video).

There is a lot of myth and misunderstanding when it comes to digital audio, and there is a lot of truth too. The loudness wars, as other posters have pointed out, has done more to damage the reputation of digital audio than anything else and there are plenty of examples of compressed (both kinds) audio sounding just terrible. One being too low a data rate combined with a terrible encoder, the other just using a small fraction of the overall dynamic range. Those are real issues but they aren't fundamental to signal reproduction.

Hope that explains some of it!

Comment: Re:Gotta be a downside somewhere (Score 5, Insightful) 151

by doublebackslash (#48122265) Attached to: Z Machine Makes Progress Toward Nuclear Fusion

Jupiter radiates more heat than it recieves not because it is a failed star, but because of gravitational contraction and something called differentiation, which is the layering of lighter and hevier elements sorting out (like dressing separating after you shake it).

The notion that Jupiter is radiating excess heat and, therefore, is a failed star is a tempting idea, but it is far from being a star. By an order of magnitude or three.

Comment: Re:bitcoin (Score 1) 241

by doublebackslash (#47949927) Attached to: Putin To Discuss Plans For Disconnecting Russia From the Internet

The answer is different in theory than it is in reality, but lets start with the theory first.

The network ca never practically be slit perfectly evenly, even if it is as more computing power is added to the problem one side will "win out" and the blockchain, by definition, is officially the longest (most complex) chain yet mined. So eventually the losing side would be undone, as if it never happened (within the scope of the blockchain... goods or services would still have been exchanged).

That assumes that all of the nodes are independent and operating following a basic set of rules and weren't rational beings. What would happen in reality is that the largest mining pools would panic very quickly. Likely they would suspend mining operations in some fashion, likely keeping the workers "busy" with bogus information and throwing away the work. What this would do is drop the hashrate of the network. Assuming coordination (or at least rational action) among the vast majority of the mining effort once the split was resolved (say a treaty was signed) the major operations would resume normal operations.
In their absence the chain would, at first, flounder, not mining any new blocks until the difficulty was re-adjusted for the now lowered hashrate. Once they came back online in a coordinated way blocks would be mined very quickly, potentially fragmenting the network until, again, the hashrate was adjusted back up. At this point the algorthim takes over and the chain with the most amount of work would win and all the other chains would disapear. This would be very controlled, however, and since the largest pools would be in a position to advertise the split and warn people very little would be lost in terms of bitcoin transactions disappearing. Mostly it would damage the reputation of bitcoin.

A slightly alternative scenario to this is that the pools suspend operations only long enough to determine who is on the larger side of the split, then resume. This would be nearly seamless to everyone on the winning side and hardly harm the reputation of bitcoin since it, along with many other services, could point to the great Internet split and blame that unfathomable one time event.

Comment: Re:if you're not reading science.. (Score 1) 770

by doublebackslash (#47853721) Attached to: How Scientific Consensus Has Gotten a Bad Reputation

Just because free will is *heavily* biased doesn't mean it does not exist.

Certainly a person deep in withdrawals from something like heroin would be desperate for relief. At the moment their free will is biased by their instinct to survive. They are in pain, they know what will take the pain away. Even if the heroin will, in the long run, kill them the acute symptoms of withdrawal tell their brain "WE ARE DYING".

That doesn't mean that the person can't seek aid, can't choose to check into rehab or be physically restrained. It simply means that free will isn't fair, it isn't weighted equally.

I don't know what your core thesis was by comparing something as nebulous as free will to a single weighted instance, and I'm not endeavoring to disagree that an addict can “simply” choose to stop, but reducing it down to a binary choice also seems incorrect.

Comment: Re:CSS? (Score 1) 306

by doublebackslash (#47651139) Attached to: New NSA-Funded Code Rolls All Programming Languages Into One

indeed! And extending the analogy even more even though we *could* write Graham's number in decimal the number of digits makes it impossible to physically realize, but we can represent it with up arrow notation with relative ease.

Granted, all of these mathematical facts don't map 1:1 back to the original debate but it does encourage thinking about programming languages not as meaningless novelties derived from one system but as a landscape of utility, each with their own merits or lack thereof.

Also +1 for citing the uncountable infinity of the reals. Learning the difference between aleph null and aleph 1 was a deeply satisfying experience for me.

Comment: Re:CSS? (Score 4, Insightful) 306

by doublebackslash (#47644673) Attached to: New NSA-Funded Code Rolls All Programming Languages Into One

I'd like to point out that you can't represent irrational numbers accurately without a new system. Let alone trancendental numbers.

Also some numbering systems are more convenient. Binary, for example. Not different numerals, but used differently.

I know, not exactly your point, but don't dismiss languages other than C, Basic, and Pascal.

Comment: Re:Requires a very high speed camera (Score 2) 142

by doublebackslash (#47600743) Attached to: Extracting Audio From Visual Information

That assumes that you only are getting one sample per frame. FTFA

In other experiments, however, they used an ordinary digital camera. Because of a quirk in the design of most cameras’ sensors, the researchers were able to infer information about high-frequency vibrations even from video recorded at a standard 60 frames per second. While this audio reconstruction wasn’t as faithful as it was with the high-speed camera, it may still be good enough to identify the gender of a speaker in a room; the number of speakers; and even, given accurate enough information about the acoustic properties of speakers’ voices, their identities.

Remember that video has two spatial dimensions with 3 channels (which themselves are in different spatial locations within each pixel) each and that each line isn't captured at the same instant. There is a lot more information there than a single sample at a given rate. Nyquist doesn't apply to the frame rate here. Nyquist is stil lrelevant to the problem, of course! They didn't break Nyquist, they just found a way to get more information than intuition implies.

Comment: Re:Not surprising (Score 4, Informative) 142

by doublebackslash (#47600677) Attached to: Extracting Audio From Visual Information

FTFA

In other experiments, however, they used an ordinary digital camera. Because of a quirk in the design of most cameras’ sensors, the researchers were able to infer information about high-frequency vibrations even from video recorded at a standard 60 frames per second. While this audio reconstruction wasn’t as faithful as it was with the high-speed camera, it may still be good enough to identify the gender of a speaker in a room; the number of speakers; and even, given accurate enough information about the acoustic properties of speakers’ voices, their identities.

They don't go into detail on the algorithm but reading between the lines it seems that they are using the spatial nature of video and the fact that not every pixel is captured at exactly the same moment (let alone each line) to ferret out higher frequency information. I have other guesses, but they are wild speculation. Either way VERY cool.

Comment: Re:Another ignorant fearmongering article (Score 1) 91

by doublebackslash (#47538217) Attached to: The Truth About Solar Storms

Came here for this, leaving satisfied.
Breaking a DC current is a hell of a lot harder than an AC current since you don't have a nice zero crossing helping you out.
Yanking the meter would give a really nice wide insulative gap AND, unlike throwing the breaker, pulling the meter disconnects not only the hot wire but also the neutral return, which would also be energized during such an event. If you didn't disconnect the neutral It seems possible that the neutral-ground tie would fry and start a nice fire inside your electrical pannel.

Just don't forget to disconnect any CATV, POTS, or other low voltage lines coming into your house as well.

Comment: Re:Can an "atheist company" refuse too? (Score 1) 1330

if you need help, ask nicely for it. stop using force to extract it from me at gun point.

We need help.
People in the USA are starving. So are people elsewhere in the world. Most of us are women and children living lives that we cannot escape because we are not free MEN. Our lives will be a consequence of the choices our fathers and husbands make. If we are lucky they will choose well and be kind to us. We suffer from TB, AIDS, malnutrition, drug abuse, the cold (in both senses). We lack healthcare because it is not available, is to expensive, or contradticts our aforementioned husband's and/or father's religious beliefs.
We have done nothing but exist and yet we find ourselves disadvantaged. Some of us have running water, and some of us don't. Some of us have education, but the vast majority can't afford to pay for it, even if we finish with high marks.
We are tired, we are downtrodden, we are many, and we are abused.
Please help us, with every fiber of your being.
Some of us are, in fact, like yourself, but victims of Compulsory Sterilization

We ask, sincerely and directly, for help from anyone who can.

We need help.

We are suffering and only need some small lifeline to find our way back and then we can begin to help ourselves.

Thank you, sincerely, for reading this far.
--99%

Comment: Re:next 50 to 100 years? (Score 1) 453

by doublebackslash (#46960445) Attached to: Study: Earthlings Not Ready For Alien Encounters, Yet

Actually an infinite universe does not contradict the Big Bang theory.
One explanation with a handy diagram (authored by an astrophysicist) http://www.astro.ucla.edu/~wri...
Another more comprehensive answer is here https://answers.yahoo.com/ques...
And something from NASA for shiggles http://wmap.gsfc.nasa.gov/univ...

I'm certain there are plenty of other discussions of the topic. AFIK we are not yet certain that the universe is('nt) infinite, we don't even know its shape, but it is possible for it to be infinite.

Currently observational evidence points to an extremely flat universe (as flat as we can measure as yet), implying its size is tremendously larger than the Hubble Volume and allowing for an infinite universe (but obviously doesn't require it).

+ - Object seen in skydiver's helmetcam unlikely to be a meteorite 3

Submitted by The Bad Astronomer
The Bad Astronomer (563217) writes "The viral video showing what looked like a meteorite falling past a skydiver made quite a splash, with many people assuming it was true. However, further analysis shows that it's also perfectly consistent with being a small (1-3 cm) rock that fell out of the parachute itself, which is a far more likely explanation."

"If truth is beauty, how come no one has their hair done in the library?" -- Lily Tomlin

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