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Comment Re:Teensy 3.1 (Score 1) 65

I'm just getting into FPGA stuff and I gotta say it is REALLY nice to get down to the metal in that sort of intimate way. I might grumble at the tools compared to what I'm spoiled with but my GOODNESS designing a tiny little soft core to do structured I/O at clock-speed (1 transfer per clock with routing and such, not that impressive but REALLY cool to dig into compared to hundreds or thousands of cycles in software!).

I don't know if I'm wired differently or if more people don't give it a try, but with the price point of some things coming out I feel like its going to get really popular. I'm using a ~$150 Zybo to develop for the Xilinx 7 series at work and Vivado is free for that chip (targeting a larger one later, and that DID cost but its obviously worth it). Thats a game changer. That brings it on par with the cost of buying a compiler in the 90s. There are even cheaper ones out there. The sucker even runs Linux so you can ship things from the pins to the kernel via DMA.

Honestly until I started working on this level I didn't appreciate it properly. Now its a world of possibilities opening up for me, and the software know-how is critical to do things like write drivers and applications on top of this hardware. No better cure for hubris than going outside of your comfort zone and starting from scratch.

Comment Re:All the proof we need (Score 3, Informative) 260

The parent is drawing their own conclusions from the article. Here is a key quote, but please read the whole article. It is actually quite good.

At this point, it’s time to ask what the heck is going on here. And while there may not yet be any scientific consensus on the matter, at least some scientists suspect that the cooling seen in these maps is no fluke but, rather, part of a process that has been long feared by climate researchers — the slowing of Atlantic Ocean circulation.

The Atlantic ocean's circulation patterns for that area are driven by density differences. Warm water from further south moves north along the surface and when it gets to Greenland it freezes as sea ice. That process greatly increases the salinity, and therefore density, of the remaining water and so it sinks and circulates south again.
This loop is critically important for certain favorable climate features of Western Europe.

If this is in fact what is occurring then this isn't evidence against climate change, it was one of the more extreme predictions OF climate change.

Comment Re:Let's face it... (Score 1) 260

It is a thing.

One anecdote that is related indirectly to the topic is the ignorance of the nature of stars. Someone in my family didn't know that stars are like our sun but much further away. There was no malice or contradiction of beliefs and they took it as a VERY awesome fact, but that sort of gap in knowledge combined with religious fervor can, and does, lead to the outright denial of even the possibility of life elsewhere.

Bear in mind that many people are in the dark about the nature of the universe as we understand it. There is no need to know and religious teachings are more accessible and repeated very often and so are positioned to become a, if not THE, dominant factor in shaping world-views. Those world views have a tendency to exclude that which the person perceives as 'other'.

Comment Re:so nasa is really a pr machine? (Score 1) 58

Is worship really the right word to use? It seems to be chosen to mock unjustly.

Adoration is natural when one appreciates something. There seems to be the implication that this is wrong, or that the attention is undue.
Certainly you aren't obliged to participate yourself, and it is natural that if one express hostile opinions then there is a natural urge to sway or discredit that person.

There is no way to know your mind from the outside, but it really does seem that you've got an axe to grind here.
If you have a specific criticism then express it, please. if not then it might be better to question your own feelings, as should everyone from time to time.

Comment Re:Need a new cryptocurrency (Score 2) 59

I tend to not think of Bitcoin as currency. A commodity fits rather well but isn't quite perfect.
I view it as a medium for the transfer of value. That gives it some value since it is competing with costly and complex alternatives such as credit card processors.

Everything else that people do with it can be seen as being derived from that. Speculation and trading are natural consequences of anything that people ascribe value to.

When used as an individual not wanting to engage in futures or investment, but only in the exchange of value for goods and services Bitcoin is interesting.

People mining bitcoins are the facilitators of that exchange, hence the reward for mining a block. The focus for many has been on the act of mining, but the actual use of it in buying / selling is much more compelling for most. You can use the exchanges to turn money into bitcoins and vice-versa and then use them to buy goods or services.

You're right that is isn't money, but that is the goal. To take it from a commodity-like to a full blown fiat currency. It is a great experiment.

Comment Re:Earth brighter than Moon - surprise? (Score 1) 77

There is actually a concept that explains this sort of thing!
It is called 'qualia'
The big idea is that no matter how much you understand an idea, no matter how detailed your mathematics, abstract understanding, or information about underlying biological processes may be the actual experience is different than be be imagined or described. These experiences are qualia.

Another way of thinking about it is a short story:
    Anne lives in a world that is monochrome. There is only shades of grey to her eyes. She has studied color, however. She understands the quantum mechanics of light emission, the wave particle duality, the idea of perception of color using cones in the eye, how that information is combined in the brain and can be distinguished. She has several PhDs on the topic of color in various disciplines.
    Anne then leaves the world without color and enters ours. She sees a blue sky for the first time.
    On that day Anne has learned something new about color.

Even though that scientist could conceive of the brightness difference the experience could still surprise him.

Comment Re: Hidden Blackholes (Score 1) 92

I'll agree that the burden of proof is on the people making the claim, but isn't that a reasonable division of labor? If a non-mainstream theory is (more) correct than other theories it may not be popular at first but it will be able to provide clear predictions and satisfy deeper mysteries than a less complete or flawed theory.
The fact that people don't tend to work on new and radical theories seems to simply be the dual onus of that theory being untested and being less known.
Theories in physics are becoming huge mathematical puzzles, so it is natural that those unfamiliar with the theory aren't keen on working with it until it has shown some merit.
In the long run anything better than what we have will win, simply by being better at what it does.
Is that so unfair?

Comment Re: Hidden Blackholes (Score 1) 92

That is a very interesting article. Note that the effect was achieved using a carefully constructed silicon crystal. Their ability to alter the light's path electrically is dependant on that changing the properties of the crystal. I tried to find a better abstract, but those are the gross details.
Regarding thinking of science as an indoctrination; I encourage you to see for yourself the level of agreement that some of these theories have with observation. They have amazing predictive power and any theory that may supplant them will have to explain at least those phenomena.

What makes you feel science is indoctrination? It does not seem to be to me. Perhaps it is a simple misunderstanding of the rigor that theories are put through? Let me know.

Comment Re: Hidden Blackholes (Score 1) 92

A magnetic field can only bend a charged particle. Photons are not charged and so are not bent.
There is a quantum effect called Delbrück scattering, but that is not bending and also the effect is weak enough to be negligible even in controlled experiments.
Further the fields Bing deflected like the tail of a comment is an interaction between the sun's magnetic field, ours, and the solar wind. It is not a "wake" in the sense that it would need to be in order to cause these effects even if magnetic fields bent light.

Comment Re:Hidden Blackholes (Score 1) 92

Time dilation effects alone cannot account for the bending of light which gravitational lensing accomplishes. Since time dilation does not change the metric of space it cannot bend light. We know that these observed effects are proper bending of light because of multiple images of the same objects as well as their distortion.

Another thing to note are that gravitational waves travel at the speed of light and so any lensing effect (and time dilation effect) that could be observed in the gravitational "wake" of a massive object would dissipate extremely rapidly relative to the motion of the object.

It is an interesting take, but it just doesn't pan out. That isn't to say that time dilation is absent, far from it, but it is not what is causing the lensing effects.

Comment Re:Hidden Blackholes (Score 4, Informative) 92

No and for two reasons.
This observation is in accordance with our models, so these aren't adding to the mass we had already inferred was there (but confirms that it is organized into massive black holes, so that is good to know)
Second, the amount of mass that is currently "dark" is about 5.4x what we can account for with all traditional forms of matter (atoms, neutrinos, light's mass-energy, etc). We know it is there based on its gravitational effects and have really good reasons to believe that it is a distinct physical phenomena (e.g. the Bullet Cluster's gravitational lensing agrees with dark matter's physical reality as opposed to a many of the proposed modifications to gravity)

Obviously dark matter is an active topic of research and so there are many areas of it that are fraught with misconceptions. Beware of simple answers which claim to be complete solutions.

I am not a researcher in this field, and this is obviously not anywhere near a complete explanation but I hope that at least clears up your question!

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

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

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.

My computer can beat up your computer. - Karl Lehenbauer