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First Phase of TrueCrypt Audit Turns Up No Backdoors

canajin56 Re:memset() is bad? (171 comments)

As a special case, MSVC++ removes memset(array,value,sizeof(array)) if array isn't read again before the end of its scope.

For example

void Foo()
char password[MAX_PASSWORD_LEN];
memset(password, 0, sizeof(password));

The MS compiler will delete the memset. In Windows you should use RtlSecureZeroMemory to zero out memory you want to keep secure.

about two weeks ago

Thieves Who Stole Cobalt-60 Will Soon Be Dead

canajin56 Re:isn't it possible to detect (923 comments)

Short answer: No. Long answer: What do you mean "big doses"? There are many sources of gamma rays in the atmosphere (when stuff like cosmic rays hit it, you get a nice shower of gamma rays and other neat thingies). Maybe if you have a gamma spectrograph you can filter out just the cobalt-60 gamma rays, assuming they're unique? In that case you just need to worry about the fact that the surface is huge and gamma detectors are non-directional. That means that to scan a point on the surface you need to point straight at it. Unless you have a massive constillation of sats that means each "square" you scan will need to have a pretty high CPM for there to be a statistically significant number of counts during the scan. Due to the inverse square law, your satellite in LEO will only see a few CPS if somebody within 1KM of the source is getting several MILLION CPM. That translates into radiation sickness within a few days. For being 1KM away. Don't even ask about being in the same room as it! And of course the area you're scanning in 1 second is pretty huge so this detector wouldn't be much help locating things. And that's assuming no background radiation on the same order (or higher) CPS.

This would change if you have a gamma ray vector spectrograph that lets you measure the exact frequency and vector of each gamma ray it detects. But right now I think the filters are pretty fuzzy AND the techniques used are all non-directional. Even assuming perfect filters and vector detectors, the counts have to be huge before they show up in space right when you're looking. And I think the assumption you even can filter so you won't see any background ticks is incorrect, but I have no idea what kind of spectral distribution the Earth's gamma background has.

The reason you can have satellites that detect and locate the gamma bursts of underground nuclear tests is because of the B word. If it's a burst then you can triangulate between satellites even though their detectors are scalar not vector. That's because the sudden uptick that each satellite sees is tied to the same physical event. If you're looking at decay emissions then the counts are not synchronized so you can't triangulate. Oh, and also the gamma ray burst from an explosion is pretty big compared to the decay from a few kg of cobalt-60.

about 5 months ago

How an Astronaut Falling Into a Black Hole Would Die Part 2

canajin56 Re:Long before the event horizon (263 comments)

That depends how high you go when you say "more massive". For example, the black hole at the center of our galaxy is 4 million solar masses, and ones thought to be as heavy as 1 billion solar masses have been spotted I believe. Lets do some basic maths of proportions. The Schwarzchild radius of a blackhole is proportional to its mass. Not the something-root of its mass, but to its actual mass. That's unexpected, and it's why the other guy was almost right (but not about micro black holes). Newtonian gravity is M G / r^2 (where G is the gravitational constant G = 6.67E-11 m^3/(kg s^2)). So it will vary with mass, and inversely with squared distance. Distance at the event horizon, we just established, will vary with mass. So force at the event horizon varies with the inverse of the mass. So a 1E6 solar mass black hole would have 1E-6 as much gravity at its event horizon. So instead of about about 1.5E13, it would be 1.5E7. That's still a lot of gravity! However, remember that we are also 1E6 times as far away. The difference that 1.5M makes is then 1E-6 as great. While you might initially expect this to be 1E-12 because of it being squared, you'd be wrong if you did so. You'll have r^2 - (r+1.5)^2 = r^2 - (r^2 + 3r + 1.5^2), or proportional to r, not to r^2. So all told, the tidal forces should vary inversely with the square of the mass of the black hole. Thus, I would expect the gradient to be 1E-12 as great, or basically 2 thousandths of a gravity over 1.5 meters. More than the tidal forces of standing on Earth, but not something that will shred you. The other considerations vis-a-vis dying in a horrifying (but thankfully brief) manner at that distance are another matter entirely. But as pointed out it's a pretty rough guess to be using Newtonian gravity while standing, as it were, directly on a singularity. And about that word: A black hole can have two different sorts of singularities. A singularity means a point at which an equation is undefined. (In the equation 1 / (1-X), X=1 is a singularity). The event horizon is a singularity in equations for relativity. At this point, length and time are 0, and mass is undefined. The second singularity is what everybody always thinks of. That is a point mass, or a point with 0 volume and finite mass. Density = mass/volume. Finite/0 is undefined, so a point mass is a singularity of a different sort. However, I should note that a point mass is only required for small black holes. As the radius varies with the mass, and the volume of a sphere varies with the cube of the radius, the density of a black hole is proportional to the inverse square of its mass. When you get to the millions or billions of solar mass black holes, the density is very low and no point mass is necessary.

about 6 months ago

Ramanujan's Deathbed Conjecture Finally Proven

canajin56 Re:Guy was so smart it's scary. (186 comments)

Newton was the Frozen-Light Alchemist. He earned his name from his ability to transform light into solid matter (and vice versa).

about a year ago

Unredacted Filings Reveal Claims of Juror Misconduct in Apple vs Samsung Trial

canajin56 Re:He didn't disclose what he wasn't asked (282 comments)

He answered yes by raising his hand. He then volunteered ONE example. He was not asked to disclose all cases. He did not misrepresent anything. He did not state he only had one lawsuit, or answer any questions as to how many lawsuits he had been involved in. That's not his fault for those questions not being asked.

What the judge said is "All right, let's go to Mr. Hogan". You are trying to say "Mr. Hogan didn't have to say anything because that's not a question, the judge just said 'let's go' and that means nothing!" However, standard voir dire instructions are that when you raise your hand and it is "your turn", you must explain your answer in "narrative form". So the reason he gave an example is not because he volunteered an example without prompting. It was because he was instructed that, when picked by the judge, he must elaborate on his yes/no answer. To repeat that, he was required to explain his answer. The judge did not vocalize that requirement at that time, because it was part of the previous instructions. That's why all of the people who raised their hand were not asked explicitly to elaborate, but they all did when he called their names. Since he was, in fact, instructed to explain, he was required to answer truthfully. Omissions are considered deceit as far as the court is concerned.

about a year and a half ago

Are SSDs Finally Worth the Money?

canajin56 Re:Not sure if you can post anonymously early or n (405 comments)

It wasn't a question of "5 times as much an SSD" (and of course much more if the SSD is idle or off) it was a question of "too much power and heat to be used in a residential situation." It's foolish to have 1TB of ram in a desktop and then never be able to turn it off without losing everything, but not because the power consumption is so high that you couldn't use residential wiring ;)

about a year and a half ago

Australian Study Backs Major Assumption of Cosmology

canajin56 Re:Aliens? (94 comments)

This doesn't change much. As mentioned, this is a pretty fundamental assumption. What this assumption gets you is that if you go big enough, all of the differences in mass distribution smooth out and everywhere is just like everywhere else. There will be a "typical" cluster of galaxies that "most" are "pretty close" to. And within such a typical cluster you can talk of a "typical" galaxy, and a "typical" star within that galaxy. But are we a typical planet in a typical solar system in a typical galaxy in a typical local cluster in a typical supercluster? Unknown ;)

What's more important is how common solar systems with terrestrial and gas giant planets are. If there are rocky planets, it's thought that more or less they will turn out the same at the same distance from the sun, (scaled by the sun's intensity of course), and depending on their mass for how well they can hold onto an atmosphere. (And of course that's wishy washy, it's argued whether or not Mars would be earth-like at our distance, if it would still have been too small to hold onto an atmosphere long-term, and if the a large moon is necessary to keep the magnetic field rolling). More or less the distance and primary's luminosity will determine atmospheric temperature, and that will determine the rate of out-gassing, and you'll get all kinds of feedback, and either end up with a Venus, Earth, or Mars depending on how the atmospheric pressure and temperature equilibriums end up balanced. There doesn't appear to be a HUGE amount of variance in elemental abundance between solar systems, except according to their age. (Even that is more of a quick rule of thumb than a hard curve). This of course isn't settled by any means. Then you have things that are less settled. How important is a moon to things? Some say our magnetic field would be gone by now without the tidal forces of the moon keeping the core etc. churning away. Others say that's silly, but it might be a bit weaker by now. Then you have to figure out how much water and such we got from bombardment by comets flung out of orbit by gas giants. How many and how large of gas giants do you need to typically get that effect? Is it even strictly necessary, or just handy? Would we have still ended up Earth-like (with much smaller oceans perhaps?) without Late Heavy Bombardment? Or would we have frozen solid without the greenhouse effect of all that water? Or did most of our water come from within anyway so at most we would just have slightly smaller oceans and slightly lower temperature? If gas giants are needed, we at least have spotted those all over the place. (In fact we've spotted them around stars we thought shouldn't have any!)

None of that is really helped or hindered by the homogeneity of the entire universe. If we can get the telescope resolution to make fair estimates on the likelihood of earth-like planets (for some definition of that term) throughout the Milky Way, then we can maybe look at nearby galaxies and guestimate how likely those stars are to be like our own stars...and from there if we can eventually look far enough we can say "OK well by homogeneity most galaxies are probably pretty close to this, so maybe earth-like planets are around about this common...ish".

about a year and a half ago

Red Hat Fights Patent Troll With GPL

canajin56 Re:Not a NPE, Is it a Troll? (98 comments)

SCO wasn't a patent troll by any reasonable definition of the term. This is not because they had a product for sale, but because they didn't sue over patents.

about a year and a half ago

Astronomers Fix the Astronomical Unit

canajin56 Re:Distance remains the same? (182 comments)

The semi-major axis is usually called the "distance" because it's equal to the averaged mean distance between the planet and the foci (one of which is the sun). Though that depends what you average over. I think if you average over time it's approximately equal if eccentricity is small.

about a year and a half ago

Black Mesa Released

canajin56 Re:Comparison to HL2 port from Valve? (130 comments)

Half-Life: Source used all of the same models and maps, but added the physics engine for rag-doll effects, used shaders for improved water effects, had some limited dynamic lighting improvements (I think?), replaced the pre-rendered 16-bit skybox with dynamic effects, and cleaned up the specular/normal maps for better bump mapping and such. That is, it was a port to a new engine, with almost no changes to the content other than the cleaned-up normal maps and the quick switch-out of the skybox. Black Mesa is not a port, but a remake. They redid all of the maps and most of the models that weren't available already as part of HL2, so it takes full advantage of all the new shaders and lighting stuff, and has much higher resolution textures and models.

about a year and a half ago

Scientists Themselves Play Large Role In Bad Reporting

canajin56 I hate Odds Ratios (114 comments)

One of the worst "bad abstract tricks" is putting your findings as Odds Ratios. What's an Odds Ratio? You probably know that the "probability" of an event is "Event over Total". The probability of rolling a 6 on a standard die is 1/6. The "odds" of an event is "Event to Not Event". The odds of rolling a 6 are not 1:6, they are 1:5 for (or more often said, 5:1 against). So then the odds ratio (OR) of two groups is the ratio of ratios, or the ratio of the odds for one event compared to the odds of another. So a big source of confusion is thinking the odds and probability are the same thing. Clearly they aren't. And clearly the closer they get to even odds, the bigger the difference. The odds of tossing a coin and getting heads are 1:1, but that's a 1:2 probability.

An example of the odds ratio in action: You ask 1000 men if they smoke, and you get 300 who say "yes" (made up statistics). That's odds of 300 to 700, or 3:7. You ask 1000 women if they smoke, and 250 say "yes". That's odds of 250:750, or 1:3. The odds ratio is then (3:7) : (1:3) or 9:7, or 1.2857...:1 So in the abstract you will see that this study has found that males have an OR of 1.29 when compared with women. And they'll just sit back and let the journalists call that "almost 30% more likely!" When it's not. That's how much higher the odds are, and odds are not probability! And of course you can't forget about confidence intervals. It's actually even worse than that. An increasing number of medical papers will take the OR of 20:1 and go straight to "20 fold more likely to blank!" when the probability ratio is 3.5:1 not 20:1.

Part of the problem is not enough statistics courses for scientists. I had to take 2 as part of my degree, and they never covered odds ratios, or odds at all actually. Only probabilities, which are more useful to reason about usually. This is further compounded by people using odds and probability interchangeably. I see on things like scratch and wins and store give aways "Odds of winning 1 in 3", which is a probability.

about a year and a half ago

Apple Announces iPhone 5

canajin56 Re:What? (1052 comments)

What good is apathy if nobody knows just how strongly you don't care?

about a year and a half ago

Foxconn Says Vocational Students Aren't Being 'Forced' To Work

canajin56 Re:I have some issues interpreting that statement (117 comments)

To add actual numbers: In the USA the suicide rate is 11.8 per 100,000 people per year, compared to China's overall 22.2. However, this is for all people. In Foxconn's worst year, they had 14 suicides, or 1.5 suicides per 100,000 employees. Making it extremely low compared to the national average for either China or the USA. Or about 2 per 100,000 if you restrict the death and employee counts to their worst (in terms of suicide) factory complex. As you said, this is about equal to the roughly 2 per 100,000 retail employees murdered per year for assorted reasons. At any rate, to get a fair comparison you would have to look at workplace suicide rates for factory employees in the USA, not just at the grand total. And as far as I know, there aren't really many such statistics available.

about a year and a half ago

FBI Denies It Held iPhone UDIDs Stolen By AntiSec

canajin56 Re:Collection != leak (216 comments)

I'd imagine that some people have their home address in their phone for GPS purposes. Or, the trojan could have been monitoring movements via GPS, and whoever was running it could have been reversing that into probable addresses. Or it could be cross referenced. If they use their wifi at home, the trojan could get an IP address. Many online stores will connect your IP address to your zip code and/or your address, and sell that data point to geomapping services. Even stores that do not sell online, but have a "find a store near me" will sell the same data. It's not always very accurate as people tend to put fake zip codes in when it doesn't matter. But still. It's important to remember that many (or most?) of these rows do not have address or zipcode information. AntiSec redacted those columns before releasing it so we actually don't even know they were present at all, and if they were, what percentage of rows had these data.

about a year and a half ago

Radio Royalty Legislation Described As 'RIAA Bailout'

canajin56 Re:Clearance; promotion (272 comments)

Write original material?

The reference here was probably to Elastica getting sued by Wire over 5 notes. So, 5 notes, regardless of tempo or key change, leaves about 40,000 unique "song parts". And of course, a large portion of them sound terrible, so there are maybe a few thousand possible parts of songs, and each song will be made of many of them. Since there are a lot more than a few thousand songs, by Wire's logic, there are no unique songs left in the world. Of course, that was settled out of court, so it's not actually the law at all ;) Except perhaps it is precedent (not in the legal sense) of having to defend against insanely absurd lawsuits from jealous bands all over the world. And that's enough.

about a year ago

Kentucky Lawmakers Shocked To Find Evolution In Biology Tests

canajin56 Re:Several states (1218 comments)

Stupidest is a perfectly cromulent word. Normally I'd be on your side, but it's a lost battle, just as "begging the question", "octopuses" etc. are lost now. (Specifically, most dictionaries list "stupider,stupidest" as the comparative and superlative forms of stupid, including spellcheck dictionaries). It may be painful to witness, but language evolves...oops, I mean, language is (un)intelligently designed.

about a year and a half ago

Leaked Emails Allegedly Tell of Global "Trapwire" Spy Network

canajin56 Re:Here's a video released by Anon about surveilla (149 comments)

There was a Canadian show I watched one episode of called "Continuum", the "good" guy (well, girl) is a "Protector" in the "CPA" (I forget if it's "civilian" or "corporate" protection). In other words, she's a secret police officer. No uniform, license to kill. The "government" is the Corporate Congress. After bringing about additional market collapses they bought out the world governments and dissolved them. The CPA doesn't arrest people directly, they implant "trackers" which work not by actually being a GPS tracker, but by inducing more and more pain until the "perp" turns themselves in at the CPA station for sentencing and removal of the excruciator (hungry rats are sooooooooo 20th century). (The pilot has her smashing somebody's face in for vandalism then implanting the excruciator). Her suit/implants record everything she sees and hears and transmits it to HQ for filing. So, bringing it back to the second post in this thread, one of her buddies calls the government Big Brother, and she says the exact same thing "It can't be because otherwise you'd be dead". All while her implants are filming and recording, and transmitting back to HQ for processing and filing.

Anyway, the whole show is so heavily "1984 but the government is the good guy" I couldn't believe it. But they make sure the "bad guys" (pro-democracy rebels) are equally unsympathetic by having them kill as many innocent people as possible 24/7 for no reason. (PS the bad guys are a government trained death squad used to put down protests, but for some reason maybe explained in episodes I didn't watch, they rebelled.)

about a year and a half ago

Legitimate eBook Lending Community Closed After Copyright Complaints

canajin56 Re:Publish and they'll perish (288 comments)

People are currently scraping forums looking for authors complaining about the site and bragging about getting it taken down. Their works are being compiled into a single torrent for easy piracy ;) The idea is to get all of these beyond-retarded inbreeds tilling at TPB so that they won't bother burning down any more libraries.

about a year and a half ago

Legitimate eBook Lending Community Closed After Copyright Complaints

canajin56 Re:Alternative? (288 comments)

It's not the publishers doing it in this case, it was the authors. And most authors don't want libraries gone completely. Oh no, they want them to pay the author 10 cents each time the book is loaned out. That's what they managed to get in England, and they are furious at how small it is (the fee, not England). They say that since each loan is a loss of a 5-10 pound sale, they are reasonably owed at LEAST one pound each time somebody borrows a book from the library, absolute minimum. The lesson is the oft repeated "give an inch and they'll take a mile." You extend copyright a year, they'll keep demanding it again and again until, oh look, it lasts 150 years. You give them a cent and they will demand a million dollars because they have come to rely on your government handouts but find they are insufficient. In this case the list of anti-sharing, anti-reading, authors needs to be published so they can be boycotted.

about a year and a half ago


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