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Comment Re:E=MC^2 (Score 4, Informative) 135

E = mc^2 specifically applies only to objects that have nonzero mass and are at rest with respect to the observer. Photons are massless and move at the speed of light.

The general equation is E = sqrt((mc^2)^2 + (pc)^2) for rest mass m and momentum p. If a particle has mass and is at rest, then p=0 so E=mc^2. If a particle is massless, then m=0 so E=pc.

(The "m" here refers to rest mass m0, not the "relativistic mass" m* which is defined as m* = m0 / sqrt(1-(vc)^2)). Relativistic mass is best thought of as a fake concept to hide the ugly sqrt denominator. People can imagine things getting heavier when they're moving, and can keep saying "Einstein discovered E=mc^2". But it still has division-by-zero problems with massless particles, and things don't really "get heavier" when they move, so if you try to avoid thinking in terms of m* you won't get as confused. Neither m nor m* makes E=mc^2 work with photons.

Imagine if a bundle of photons could gather and form a "black hole". The hole and its event horizon would be constrained to move at the speed of light, which you can't, since you have mass. so you might easily escape its event horizon- you wouldn't have time to fall in before the thing was gone. Real black holes have mass and don't move at the speed of light relative to anybody.

Comment Re:That's Racist (Score 1) 69

Race: "Race is a classification system used to categorize humans into large and distinct populations or groups by anatomical, cultural, ethnic, genetic, geographical, historical, linguistic, religious, and/or social affiliation."

This study is enabling not only genetic but geographical distinctions. The connective "and/or" is synonymous with the logic connective "or" which is inclusive.

Racist: "Some definitions consider that any assumption that a person's behavior would be influenced by their racial categorization is inherently racist, regardless of whether the action is intentionally harmful or pejorative, because stereotyping necessarily subordinates individual identity to group identity."

While it is true that, in itself, mere genetic distinctions do not imply any distinctions in behavior, it is also true that if one finds genes influence behavior (which one can clearly see in the distinctions between species) then one can reasonably impute that there will be statistically significant distinctions in behavioral predispositions between genetically distinguishable groups. This "reasonable imputation" does not have to be proven or shown to be the case to be applicable in practical everyday life for the average person -- it merely needs to be not disproven to that average person.

Comment Re:need to get over the "cult of macho programming (Score 2) 231

I actually agree with both of you. The Open SSL guys gave out their work for free for anybody to use. Anybody should be free to do that without repercussions. Code is a kind of literature and thus should be protected by free speech laws.

However, if you pay peanuts (or nothing at all) then likewise you shouldn't expect anything other than monkeys. The real fault here is big business using unverified (in the sense of correctness!) source for security critical components of their system.

If regulation is needed anywhere, it is there. People who develop safety and security critical stuff should be certified and businesses with a turn over $x million dollars should be required to use software developed only by the approved organisations.

There is nothing in this definition that prevents an open source implementation. In fact, there's an argument to say that any such verified implementation must be open source precisely so it can be inspected. But it is quite a lot of work and people need to be paid to do that work. You can't expect to get this level of quality assurance for free.

Comment What scams? (Score 2) 90

Kickstarter has hardly had any scams. Pretty much everything I've backed has been delivered, sometimes much later than planned but delivered eventually.

If you can't tell what is probably a scam and what is not, that's a problem that will haunt you in many other ways beyond just Kickstarter...

Comment Where are the 3.5" SSDs? (Score 4, Interesting) 264

Why do SSD makers only make 2.5" SSDs? It seems like a lot of the capacity limitation is self-enforced by constraining themselves to laptop-sized drives.

Why can't they sell "yesterday's" flash density at larger storage capacities in the 3.5" disk form factor? For a a lot of the use cases, the 3.5" form factor isn't an issue. More, cheaper flash would enable greater capacities at lower prices.

The same thing is true for hybrid drives -- the 2.5" ones I've used have barely enough flash to make acceleration happen, a 3.5" case with a 2.5" platter and 120GB flash would be able to keep a lot more blocks in flash and reserve meaningful amounts for write caching to flash.

Comment How risky? (Score 1) 548

DoJ is encouraging banks to close bank accounts of risky actors.

How are porn stars "risky" in any way? They make a fair amount of money, what they do is legal beyond all doubt.

What the DOJ is doing, is helping re-define what "risky" means according to some victorian moral code.

Strangely enough none of them are big names. Its almost like someones trying to create a story where there is none.

Because it's easier to attack the weaker members of the flock first before you take out the last few remaining. The presumption would be by the time anyone noticed, it would be too late - and it would in theory provide a chilling effect on new people entering the adjust industry, killing off the industry by shutting down supply.

Comment This mostly makes sense to me (Score 1) 548

While I'm sure there is a lot of room for abuse, I kind of applaud this action.

I think far too long the government has let banks and payment processors off the hook when it comes to enabling fraud.

A lot of fraud wouldn't exist in our modern world if it didn't have access to financial services. In some ways its the air supply of fraud.

Comment No, that's stupid. (Score 1) 324

Averting the consequences of climate change require people en mass to change their behaviors. No such change in behavior is required for Nuclear disarmament.
Plus many large wealthy company will have to be satisfied making slightly less money, they aren't thrilled about that.
Also some Jobs may be lost as a result of those diminished profits.

All of the nuclear weapon creation jobs are long gone. All the work around them is related to maintenance and dismantling them. Some people are benefiting from the dismantling, very few are suffering.

Comment Re:No way I could trust a self-driving car (Score 1) 98

I don't know about GPS units, but I've had Google Maps send me on a complicated route through the alleys of a small town because someone forgot to enter a permitted turn at the intersection of two major highways. I've had it tell me to drive through a concrete barrier because someone recorded the intersection as a cross intersection rather than back-to-back "T" intersections. I've had it give me a route four hours longer than necessary, because it thought part of the short route was still closed for the winter. And most recently, it give me a route that ended twenty miles short of my destination because it picked the park administrative headquarters in a nearby city as the location of the park, rather than somewhere actually, you know, *in* the park.

Comment Re:NO NO NO!!!!!!!! (Score 1) 297

No you could build an RC airplane that could fly over a tornado. All it would take money and a good engineering team. A turbocharged engine and a high aspect ratio wing is all you really need along with a good control systems.
I believe that someone did launch a glider from a weather balloon at an altitude above most tornados. I do not think it was in the US and well outside any urban areas but still probably a violation of regulations but I am not sure.

The law for RC aircraft places a legal altitude limit. So that statement was wrong in that it is illegal for both of them, no news station or hobbiest has flown over a tornado, and the story was not about flying over a tornado.

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