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Comments

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U.S. Supreme Court Upholds Religious Objections To Contraception

doublebackslash Re:Can an "atheist company" refuse too? (1330 comments)

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%

about two weeks ago
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Study: Earthlings Not Ready For Alien Encounters, Yet

doublebackslash Re:next 50 to 100 years? (453 comments)

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).

about 2 months ago
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Firefox 27 Released: TLS 1.2 Support, SPDY 3.1, SocialAPI Improvements

doublebackslash Re:Too late, switched to Chrome (167 comments)

I'm actually working on a fairly JS intensive algorithm right now. FF's JS engine is, on this test, *slightly* faster and a bit less memory intensive. Subjectively chrome has a faster layout engine (I'm not testing that right now and , honestly, I try not to anger that particular demon since reflow is the slowest thing one can do in JS!) .
Right now it is a bit of a wash. *This is a good thing.* Everyone chasing each other, trying to out-perform, out-do, etc. Remember before the browser speed wars? How slow it was be default? Sub-second laoding-procesing-rendering times wasn't always the norm!
Pick whichever browser you want. IE10+, FF, Chrome, etc etc. They are all relatively compliant, fast, and will serve you well. Choose on features!

Isn't the future awesome?

about 6 months ago
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Stephen Hawking: 'There Are No Black Holes'

doublebackslash Re:SubjectsInCommentsAreStupid (458 comments)

I really like Wikipedia's opening line on science:
“Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.”

I also like the opening monologue from “Haloween on Military Street”:
“We measure things by what we are.
To the maggots in the cheese, the cheese is the universe.
To the worms in the corpse, the corpse is the cosmos.
How, then, can we be so cocksure about our our world?
Just because of our telescopes and microscopes and the splitting of the atom?!
Certainly not
Science is but an organized system of ignorance!
There are more things in Heaven and on Earth than are dreamt of in any philosophy.
What do we know about the beyond?
Do we know what's behind the beyond?
I'm afraid some of us hardly know what's beyond the behind”

Both, in their own way, do a good job of highlighting that our knowledge is fallible, and that at best we can hope to merely organize our understanding as it stands and find ways forward.

It would seem that claiming that science has a “monopoly on truth” is at odds with the admission that the grand sum of scientific knowledge stands upon the single caveat that it is based on observation, experimentation, and repeatability.

I agree that it would be the height of hubris to believe that we will or can understand everything in the universe, but it is not hubris to attempt the understanding of everything we have power to.
Whomever gave you the impression that humans are in any way infallible, weather following the scientific method or not, was a zealot.

Science is a way to organize knowledge. The scientific method is a way to observe, experiment, and theorize such that we can obtain theories that fit those observations and can be reproduced. Any other claims are either ancillary or false.

about 6 months ago
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Chrome Is the New C Runtime

doublebackslash Re:Java as the cure for "bloat"? What the fuck, so (196 comments)

It isn't that insane. Instead of remapping one page at a time the queue up a number of changes and commit them all at once. This is because on stock Linux every page table re-map creates a lot of cache coherency traffic to make sure all the processors know of the new mapping. By committing them all at once they only need one round of that.

http://www.azulsystems.com/sites/default/files/images/c4_paper_acm.pdf

Section 5.1 is where it starts going into some details on that.

about 6 months ago
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Coca-Cola Reserves a Massive Range of MAC Addresses

doublebackslash Re:The real question here... (371 comments)

On your own network that is under your complete and absoloute control there isn't an overwhelming need to have a globally unique MAC address. Sure, it is nice to be able to plug any device into your network without having to assign the MAC address to guarantee uniqueness, but that is just convenience.

If you don't control every single aspect of your network or don't wish to (or are incapable of) managing everything to the level of the MAC address (which needs to exist under the current protocols. It need not exist in an absolute sense, but with what we use today it is required and works rather well) then having a central authority issuing unique blocks to all takers is a good strategy.

So I guess there isn't an advantage to “owning” a block. The advantage is that everyone knows that their MAC addresses are globally unique and, therefore, can plug and play on any network.

As to Xen throwing a fit, I'd say it was a misguided security feature of some sort, but that is just speculation.

about 7 months ago
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Asm.js Gets Faster

doublebackslash Re:Or anything running in a VM (289 comments)

Just fine, at least I do. Just different sets of optimizations to keep in mind, as well as different expectations. I don't think any reasonable person would approach the two problems the same way, but it all boils down to basic computer science.

Light up pin 1 when the ADC says voltage is dropping which indicates that pressure is too low on the other side of the PPC. Compare that to indexing a few gigs of text into a search engine. Completely different goals, completely different expectations. I'm not master of the embedded domain, but I don't think it is a dark art.

Perhaps I'm looking at it the wrong way or perhaps my experience is unique or at least rare, but in my eyes it is all the same thing at different scales. Tell me my app is using too much memory then I'll first look at how I can reduce memory pressure, then I'll tell you what is and isn't possible to do and give you a list of sacrifices that would be needed to reduce memory pressure (time to refactor, concurrent operations, latency because of disk, etc etc etc. Not just talking about capabilities but the whole deal). Find the balance and go for it. On the embedded side the same sorts of compromises are made but the scale is just so much smaller. Finite number of IO pins, time to optimize your code to accommodate a new feature, meeting real-time, writing something in ASM to get around a GOD FREAKING AWFUL EMBEDDED COMPILER, etc etc etc.

I dunno, do I have my head on straight here? All seems fairly straightforward in the end. Specialists can do their bits faster than someone less familiar but with equal skill and understanding. Thats what earns the bucks, getting things done in a timely fassion.

((Or at heart I'm an embedded guy. Possible!))

about 7 months ago
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Japan Aims To Win Exascale Race

doublebackslash Re:Yes but... (51 comments)

Farily small. 60663.20 Peta FLOPS (60 exaflops) at my time of clicking if those numbers can be trusted (likely since the network hashrate can be derived from the average speed of blocks being found) Not that bitcoin mining uses floating point units since it is brute forcing a hash... but I digress.

about 8 months ago
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CAPTCHA Busted? Company Claims To Have Broken Protection System

doublebackslash Re:Better than humans (141 comments)

That is really lazy work on the programmers part. It is trivial to use AJAX to submit the form and selectively wipe the captcha field whist refreshing the captcha. Thats what I do when we require a captcha for one reason or another.

about 9 months ago
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How Early Should Kids Learn To Code?

doublebackslash Re:When they want to. And ONLY when they want to. (299 comments)

I really agree with you.

My take on it, from both my personal experience and my interaction with my little cousins and the like, is that children don't have the breadth of knowledge, but they have great depth of knowledge. Kids can be schokingly insigtful in areas that they've explored.

I taught myself how to program starting when I was eight (I wanted to, though, quite badly.), and my parents gave me every single tool that they could to further that even though they are both highly non technical. Sure, they didn't like me spending all day on the computer, and they didn't really understand how the thing worked, but they encouraged my particular talent and intrest and I became very good at what I do because of it.

My wife is the same way, but she is a designer. Same situation (piles of her old art still haunts my in-law's house) and it was the same result.
Recognize what your kids are good at, help encourage it however you can. I'm certain that to any decent parent this is obvious, but I feel like it doesn't get said enough. I know what a difference that can make to a growing mind and it is how I plan to parent my child when I have one. I might try to sneak a little logic and critical thinking into them when they think they are having fun, though. Hope they don't mind.

about 10 months ago
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Why Is Microsoft Setting More Money On Fire With Surface 2?

doublebackslash Re:XBOX? (616 comments)

A fair point. "Wholly custom" is hyperbole, on further reflection.
Especially considering that most of the changes I'm aware of were outside of the ALU and trickier main meory logic, like cache coherency, and I'm certain IBM was more than helpful. Way cheaper than developing a cell or some other new tech from scratch.

+1, very well considered point.

about 10 months ago
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Why Is Microsoft Setting More Money On Fire With Surface 2?

doublebackslash Re:XBOX? (616 comments)

Nope! I was a bit checked to learn that it is a true-blue down-to-the-metal tri-core myself! but decapped processors don't lie http://www.dvhardware.net/article6606.html

Weird, right?

about 10 months ago
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Why Is Microsoft Setting More Money On Fire With Surface 2?

doublebackslash Re:XBOX? (616 comments)

The processor in the xbox 360 was a wholly custom part. It has extra components to encrypt and hash memory to and from main memory (only the hypervisor is hashed, the rest of memory is encrypted) as well as e fuses for locking out downgrades. It is also a 3 core part, definitely uncommon.
Much more information in the google tech talk The Xbox 360 Security System and its Weaknesses .

Really good tech talk, worth watching if you are interested in that sort of thing, as well as the original Deconstructing The Xbox Security System for the original xbox.

Enjoy!

about 10 months ago
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MIT Research: Encryption Less Secure Than We Thought

doublebackslash Re:good news for NSA (157 comments)

Some stream ciphers are as you say, but the keystream is not the same as the underlying key. One can't guess the next character in the keystream without deriving the key. Most modern stream ciphers use internal feedback much in the same way that block ciphers use external feedback modes, like CBC, to prevent these attacks.

In any system without feedback like this it is always considered insecure to re-use a key at all.

about a year ago
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MIT Research: Encryption Less Secure Than We Thought

doublebackslash Re:good news for NSA (157 comments)

I'll undo my moderation in this thread just to tell you that you are wrong. One cannot determine the key from the ciphertext. If they can this is known as a "break" in the cipher.

A "break" in a cipher does not mean that it is practical to find the key, merely that it is more feasible than mere brute force. For example, a "break" could reduce the effective strength of a cipher from 256 bits to 212 bits under a known plaintext attack. This is a BAD break in the cipher given current standards, but it is the cipher is still completely uncrackable in human (or even geologic) timescales.

The "weeks or months" number, by the way, has nothing to do with cracking cryptographic keys. I would surmise that is a number more geared towards cracking passwords, which is an entirely different topic. Also, for some realistic numbers on cracking encryption keys, check out Thermodynamic limits on cryptanalysis

about a year ago
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Banker Offers $1M To Solve Beal Conjecture

doublebackslash Re:Fermat? (216 comments)

Similar, but Fermat's Last Theorem states that no integers x,y,z can satisfy the equation x^n + y^n = z^n where n is an integer > 2
This one allows every exponent to vary separately as well as the bases and is trying to make a guarantee rather than proving an impossibility (and, contrary to popular belief, proving a negative is not only possible but trivial to prove )

about a year ago
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WY Teen Cut From Science Fair For Entering Too Many

doublebackslash Re:How? (204 comments)

It does not take talent to waste power.
It takes talent to build a fusor from scratch.
It takes talent to build scintillators, or even use existing one, to get a spectrum from your reaction to know the exact reactions that are occurring and in what proportions.
It takes talent to keep yourself safe using such a device.
It take drive and motivation and a damn side more vision than most people have to attempt such endeavors. This is the Hello World for a nuclear physicist and I encourage such behavior.

If all you can see is someone "wasting" electricity I think you've missed out on a much larger picture.

about a year ago
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Avatars Help Schizophrenics Gain Control of Voices In Their Heads

doublebackslash Re:schizophrenics aren't violent (138 comments)

ugh, sorry. forgot some words, was focused on making the numbers correct:
(5% of schizophrenics * 1% of the population) = 0.05% *of the general population* are violent schizophrenics
vs
    3.025253% of the general population are violent non-schizophrenics (This would be the overall rate after discounting both violent and non violent schizophrenics)

about a year ago
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Graphene Yields Another Trick: Ultrashort Laser Pulses

doublebackslash Re:femtosec is not ultra short (24 comments)

I just went on a mini wiki binge based on that refutation. Thanks.

It would seem that although femtosecond pulses are not on the scale of the state of the art (attoseconds) they are still considered "ultra-short" by the optics community. The real news would seem to be the range of frequencies that can be produced (both the breadth of frequencies and, specifically, some frequencies that are difficult to work with) and little more.

Only one paper wasn't behind a paywall, and I'm not a trained scientist, (So if I make a mistake someone PLEASE CORRECT ME) but from what I can glean graphene will happily absorb nearly any wavelength of light because of the lack of a bandgap between free electrons and bound electrons (this is the opposite of what you find in, e.g. semiconductors where there is a meaningful power gap). Electrons in graphene can be exited to any quantum level within a wide and useful range. In fact it seems that it absorbs so much of the energy that they had to dope the graphene to reduce its absorption. It is also notable that the graphene wasn't hard to produce. They produced flakes between one and three layers in solution, filtered out the water, cooked for a bit, and the resultant jumble of flakes was A-OK and only ~1/3 graphene by volume. Far easier than producing something more pure or large scale.

The graphene is pumped in a "lossy" mode to bump electrons up in energy (this is the "low Q" or "low quality" resonator mode) and then the resonant cavity is bumped to "high Q" mode. Since the graphene absorbed so much of the pumping light, and did so over the entire bandwidth of the pumping laser, when the mode is switched it lases brightly and all at once. (This is, in short, "how to build a Q-swtiched laser")

The key difference with graphene is that it absorbs practically any frequency of light without any modification. This is the special property, the lack of tuning required for a "saturable absorber". As far as I can tell this means that the material can store a certain amount of energy from the laser pump with low losses until it becomes saturated. I interpret this as a sort of optical capacitor (low loss energy storage) where as more traditional absorbers are leaky capacitors at frequencies that they are not tuned for.

Not sure how significant the optics community will find this, but it does seem to be a meaningful technology rather than a "trick" or some "in 5 years" promise.

about a year ago

Submissions

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WWVB Celebrates 50 Years of Broadcasting Time

doublebackslash doublebackslash writes  |  1 year,19 days

doublebackslash (702979) writes "On July 5th WWVB, NIST's timekeeping radio station transmitting near Fort Collins, will celebrate 50 years of continuous operation. Operating at 60kHz the signal actually follows the curvature of the Earth via a trick of electromagnetics, allowing nearly the entire globe to receive an accurate time signal, which has in recent years reached an accuracy of 1 part in 70 trillion. Recent upgrades, which came in $15.9 million under budget will allow the station to be better received even in large buildings, giving it an edge on timekeeping that not even GPS can touch, with its need for open skies to receive a signal."

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