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Comment Re:Several errors. (Score 1) 337

Sure, for some definition of "constituent parts". The relativistic jets at each pole of a spinning black hole are made up principally (overwhelmingly) of naked subatomic particles like protons, antiprotons, electrons and positrons. (At least, that's the current theory. Our observational data is sorely lacking.)

They don't get broken down further because then you'd have naked quarks, and the Nuclear Strong Force gives that one an emphatic thumbs-down. Quarks are always found bound together; they are never found in isolation.

Comment Re:Several errors. (Score 2) 337

Sigh. This is the last I'll be writing on the subject, because you're apparently not even bothering to read your own links.

  1. Unless, of course, He did. The physics checks out; We've recreated the conditions in the lab. Not hardly. Check your own link: it says several times that an analogue of a gravitic event horizon was used, not an actual event horizon. We haven't recreated a gravitic event horizon in the lab. To the best of our knowledge we've never created a gravitic event horizon in a lab. Finally, demonstrating that something works in an analogue of an environment is useful and illuminating, but it is not in any way proof that it works a certain way in the actual environment. I repeat that Hawking's work in this area is ground-breaking and critical and widely believed to be a correct description of reality, but it is not proven, not even in the loosey-goosey sense of the word. Remember that at one point the luminiferous ether was the best description of reality, too.

  2. If it's not rotating at the speed of light, then the particles do not 'think' better of it and shoot out the poles... where would they get the energy to escape from the accretion disk then? If I throw two tennis balls and they collide, they bounce off each other. If I want to make them bounce harder (travel faster), I just throw them harder. The analogy is near-exact for particles. Once they've gone from light-years away to the event horizon they've picked up an unthinkable amount of energy from descending through the gravity well. All it takes is a collision and the vector changes and the particle will go away from the black hole like a bat out of hell. And if it was traveling with more than escape velocity -- which is possible, since we're outside the event horizon -- that particle will never return to the black hole.

  3. However, here's the glitch that you missed: Non-rotating black holes also emit energy. I didn't, actually. Stationary black holes are also believed to emit Hawking radiation. However, since it will not become visible until the ambient temperature of the universe drops below a millionth of a kelvin or so, no astronomical black hole has ever been observed radiating Hawking energy. (Black holes of a Planck mass or so are conjectured to exist and to evaporate almost instantly via Hawking radiation, but stellar-mass holes just don't.) A stellar-mass black hole emits Hawking radiation of only about 50 nanokelvins (!!), meaning it cannot be detected against a cosmic microwave background of 2.7K. This also means that instead of evaporating via the Hawking process, stellar-mass black holes will gain mass from the CMB rather than radiate away.

  4. Science isn't about absolute proof, it's about the best fit model. Yes. On this point we're agreed. But when you make false claims about something having been proven when it hasn't been (hell, we haven't even directly observed a black hole yet, so even that's a lot less settled than many people might think!), claiming that demonstrating something in an analogue is the same as proving it in the real environment, and so forth, it just destroys your credibility.

Seriously. Sit down with a good graduate-level textbook on general relativity. You have a grasp of this subject that veers between the accurate and the wildly inaccurate. Science deserves better than that.

Comment Several errors. (Score 5, Informative) 337

In no particular order:

  1. Hawking proved... No, he did not. Hawking has a mathematical description that's consistent with quantum mechanics and general relativity, but that doesn't mean the universe actually works this way. There have been a large number of highly promising theoretical constructs that have never been observed in reality and are believed to not exist. Hawking radiation may be one of them. Most physicists believe Hawking radiation exists and is a real phenomena, but it has never been observed in reality. (We have, however, observed analogues to Hawking radiation from acoustic 'black holes'.)

  2. Highly charged particles are emitted at the poles of a black hole... No, they are not. Those jets are made of matter that was about to cross the event horizon until they suddenly and violently thought better of it. The area around an accreting black hole is perhaps the most violent spot imaginable in the universe; it should be no surprise whatsoever that once something has gone around the accretion disc a few million times it would have enough kinetic energy to go like hell off in another direction as soon as it collides with another particle. One of the billiard-balls rockets across the event horizon and the other uses its kinetic energy to escape from the accretion disc. (This is handwaving a lot of astrophysics, but is basically accurate.)

  3. the black hole itself is also rotating at the speed of light... No, it is not. Black holes have to obey the cosmic speed limit just like everything else. Also, not all black holes possess angular momentum. General relativity gives perfectly satisfactory predictions for stationary black holes.

  4. The information, that is the quantum state, of mass and energy that is eaten by a blackhole is later ejected as what could be termed high energy 'noise'; x-rays and gamma rays. Not in the slightest. Hawking radiation is about the longest-wavelength (which means lowest-energy) stuff in the universe. The reason for this is really simple: although it started off as unbelievably energetic, it had to expend virtually all of its energy escaping from where it was created a nanometer beyond the event horizon.

No offense, but you need to sit down with a good book on general relativity. (I like Sean Carroll's Spacetime and Geometry. YMMV.)

Comment Nowhere near blatantly corrupt (Score 1) 1233

I suggest an experiment. Run a red light and get pulled over. When it comes time to hand over your license and registration, wrap a $50 bill around it before handing it over to the cop.

If the cop returns your license and registration but not the fifty, and apologizes to you for his error... then you live in a blatantly corrupt country.

Otherwise, you live in a country that does not live up to the ethical standards you wish it would, but it is not a blatantly corrupt country.

Good grief, man. If you seriously think the United States is a blatantly corrupt country, what the hell do you call Afghanistan or Libya?

Comment Re:weird (Score 1) 712

So what?

The point is this: the person I was responding to claimed that the English Civil War demonstrated that the origin of power in the United Kingdom was just as rooted in rebellion as the origin of power in the United States is. And that's simply not true. Elizabeth II (who is not a figurehead monarch: she is the only person in the UK who can authorize war or declare peace, and that's one hell of a power; further, she can unilaterally block Parliamentary attempts to limit the Crown's interests or royal prerogatives -- a monarchial benefit that I find hard to believe still exists today in the UK) traces her right to rule back to William the Conqueror, not William Who Ended Oppression. Elizabeth II's authority derives from a long-ago act of conquest, not a long-ago act of rebellion.

With respect to "I think I disagree with you that it's a good thing," I never said I believed the US's national-origin story was a good thing. I only said that it was ours. I'm not saying the UK national-origin story is bad because it's rooted in conquest, nor am I saying the US national-origin story is good because it's rooted in rebellion. I'm only saying they're different and shouldn't be expected to be the same.

Comment Re:weird (Score 1) 712

Although I agree that the UK is a model system for democracies everywhere, that's not the point. The original poster said that unlike much of Europe and Asia, America traces its origins back to the overthrow of absolute rule rather than someone's imposition of it. A respondent argued that modern-day Great Britain was obviously an exception to that, due to the English Civil War. I don't buy that. If you trace Elizabeth II's ancestry back, you reach William the Conqueror. The entire reason Elizabeth is monarch is because she happens to be the descendant of someone who imposed absolute rule. The basis for Elizabeth II's monarchy rests in William the Conqueror's invasion of England, whereas the basis for Barack Obama's presidency goes back to the overthrow of George III's rule.

Comment Re:weird (Score 1) 712

Sorry there are plenty of examples either way, where this happens. Very recent one's, even ongoing one's. You are just cherry picking.

If I'm cherrypicking, then it ought to be easy for you to find five clear counterexamples for each of my examples. After all, I'm cherrypicking. I invite you to do this. If I'm in error I'd love to be corrected. The requirements are simple:

  • It must be state-sponsored, or at the very least state-condoned, domestic oppression
  • It must involve large amounts of lethal violence
  • The enforcers of the state must be willing participants
  • The oppressed must be in a disarmed state
  • The oppressed must overcome the oppressors.

Nelson Mandela and the ANC doesn't count: he started his career in armed insurrection. Suu Kyi doesn't count: the Burmese military rank-and-file were passively refusing to enforce the junta's orders. (For instance, allowing visitors to come and go from her place of detention pretty much at-will, and turning a blind eye as she talked to the media.) Ceaucescu's Romania doesn't count: the enforcers were defecting to the protesters in record numbers. Honecker's East Germany doesn't count: when the Berlin Wall fell East German guards were among the most enthusiastic participants. Gandhi doesn't count: he was depending on English decency and sense of fair play to keep his followers alive. (Had Great Britain handled Gandhi the same way they handled 19th-century uprisings in India, Gandhi would have been strapped to a cannon and executed long before he made it halfway to the sea for his salt.) Yeltsin doesn't count: when the KGB ordered their elite counterterror forces to take back government, the counterterror forces refused.

When the people with the guns refuse to use guns, yes, unarmed protest movements can have stunning successes. I'm all in favor of them. But when the people with the guns are willing to use them to ensure their continued rule, unarmed protest movements turn into massacres.

If I'm cherrypicking, then show me five counterexamples for each of the large-scale massacres I showed. Just make sure they pass the requirements, because otherwise you're moving the goalposts.

Comment Re:weird (Score 2) 712

Of course only an American would think that they are unique in overthrowing tyranny.

He never said we were unique. He only said that in comparison to Europe and Asia, our country was not founded by a conquering king. You hold up Great Britain as an example of a country that's thrown off tyranny, but I suspect you never quite passed your A-levels in history. Queen Elizabeth II is a direct descendant of William I, after all, a guy better known to history as William the Conqueror. So, no, I'm not going to accept Great Britain as an example of a country that avoided being founded by a conquering king, given a conquering king is in the direct ancestry of your current monarch.

We also find some sections of the American populace self centered, selfish.

I'd be quite surprised if you didn't. In a nation of over 300 million people there are going to be large portions of it that you don't like. There are large portions I don't particularly like, either.

I honestly think your founding fathers is they could see what you have become as a nation would disown you.

Of course they would. "Wait, you gave the vote to women, people without property, and the darkies?!"

In the Jefferson Memorial in Washington, D.C., one of Jefferson's finest writings is engraved on the wall in huge letters for the world to see.

"I am not an advocate for frequent changes in laws and constitutions, but laws and institutions must go hand in hand with the progress of the human mind. As that becomes more developed, more enlightened, as new discoveries are made, new truths discovered and manners and opinions change, with the change of circumstances, institutions must advance also to keep pace with the times. We might as well require a man to wear still the coat which fitted him when a boy as civilized society to remain ever under the regimen of their barbarous ancestors."

So, yes, we would definitely be disowned by the Founding Fathers. But that's okay. Thomas Jefferson himself gave us permission to improve upon the model they left us. The Framers were horribly flawed human beings. Their great triumph was not that they gave us a Constitution, but they gave us a process: not a law fixed and unchanging for all time, but a means by which we could gradually make our country a shining beacon upon the hill. Rather beautiful, really.

Ah, I see. You were actually meaning to imply they'd be ashamed of how we conduct ourselves because we don't happen to agree with you? Well. Speaking as a Virginian, which is to say a member of one of the original Colonies that rebelled against George III, let me give you the traditional Virginian response to foreigners who want to tell us how we should rule ourselves: go away.

Maybe our system is correct, maybe it's not. Either way, we're not going to pay your opinion about how we should live the slightest tinker's dam of attention. Instead we'll talk with each other, our communities, our neighbors, and we'll fumble our way forward into the future together.

This idea that an unarmed populace couldn't fight a tyrannical government is pretty weak to be honest.

I'm sorry, I couldn't hear you over the death-knells of the millions of oppressed North Koreans, over the conflagration of the Jews and the Romany and the homosexuals and the dissenters in German-occupied Poland, over the cries of hunger of the one million Ukrainians who died in the Holodomor, the terrorized shrieks of the Armenians who were pursued by the Turks. We can go back even to the Mongol era, where the great Khan put large parts of Asia and Europe to the sword and unleashed a campaign of rape and terror the world had never seen before.

If you really think that an unarmed populace can quickly organize to resist an armed oppressor, then you are living in a state of utter delusion. In the Katyn Forest a few thousand unarmed Polish soldiers were mercilessly executed by Stalin's troops. They were unarmed, but trained and organized and brave and courageous and they died like vermin.

My original remark about how you didn't pass your A-levels in history was sarcastic, I admit. But now I'm thinking that maybe I'm right. Your grasp of massacre and oppression seems extraordinarily weak. Read The Gulag Archipelago or A Day in the Life of Alexander Denisovitch. Why didn't those oppressed peoples rise up? Because Stalin's thugs were the ones with the guns.

Your example about the Spanish Civil War is also kind of ... have you ever heard of the POUM Militia, the Workers Party of Marxist Liberation? They're one of the factions you talk about in the Spanish Civil War. Your countryman George Orwell fought briefly with them and wrote movingly about their courage. They died, horribly, for many reasons -- a lack of firearms being one of them. Go read Orwell's Homage to Catalonia.

Time to evolve and change?

It's always time to evolve and change, but I don't trust your judgment in how we should evolve and change. Not even a little bit.

The Military

United States Begins Flying Stealth Bombers Over South Korea 567

skade88 writes "The New York Times is reporting that the United States has started flying B-2 stealth bomber runs over South Korea as a show of force to North Korea. The bombers flew 6,500 miles to bomb a South Korean island with mock explosives. Earlier this month the U.S. Military ran mock B-52 bombing runs over the same South Korean island. The U.S. military says it shows that it can execute precision bombing runs at will with little notice needed. The U.S. also reaffirmed their commitment to protecting its allies in the region. The North Koreans have been making threats to turn South Korea into a sea of fire. North Korea has also made threats claiming they will nuke the United States' mainland."

Comment Bad, bad advice! (Score 1) 409

When talking with a prosecutor, you should never say absolutely nothing. If you remain silent in the face of an accusation, your silence can be entered into evidence against you under the rules governing adoptive admission. If someone asks you, "So why did you kill him?" and you remain silent, your silence can be considered by a court to be an admission that you killed the person in question.

Not every instance of silence is admissible as an adoptive admission -- but the Federal Rules of Criminal Procedure are complicated and varied and unless you're a criminal defense lawyer you probably have no way of telling when silence is a good policy and when it will get you in trouble.

So, instead of being silent, you instead say, "If you give me your card, I'll have my lawyer get in touch with you to answer your questions." You take the card, you give it to your lawyer, and you follow his or her advice.

A good overview of the law regarding adoptive admissions and your potential risk when facing prosecutors: How To Avoid Going To Jail Under 18 USC 1001 For Lying To Investigators.

Comment Re:Clip (Score 4, Interesting) 1862

A good rule of thumb is that in a self-defense shooting scenario, 4 of 5 rounds fired will miss. (These numbers are born out by the historical record, BTW: they're not made up. Consider when the NYPD shot Amadou Diallo. Five officers, part of a highly-trained unit with advanced firearms training, opened fire on an unarmed and harmless Diallo from a range of under five meters. Despite the tactical environment being perfect -- the officers were at point blank range, they all had the time to make a proper firing stance, etc. -- of the 41 rounds fired, 22 rounds missed. That's over a 50% miss rate under perfect conditions by well-trained personnel.)

Another good rule of thumb is that you need to place a minimum of two rounds into your target to have good -- not necessarily great, but just good -- odds of stopping the threat.

Do the math and you quickly discover that to place two rounds on target, with each round having an 80% chance of missing, results in you needing 14 rounds in the magazine. That means that with a 15-round Beretta 92, a 17-round Glock 17, a 16-round FN FNP-9, a 13-round Browning High-Power, etc., you can be relatively confident of having enough ammunition in the magazine to stop one -- one -- attacker.

There's a reason why cops carry high-capacity magazines and at least two spares, and it's the same reason why civilians who use pistols for self-defense need high-cap magazines and at least two spares.

Comment Re:It is alarming for a judge to say this (Score 1) 584

Sorry: I'm not going to join an argument about that. I will only reiterate what I said: our rights exist independent of the technologies used to implement those rights. If we have the right to freely communicate with other human beings, then we also have the right to put up web pages: the technology exists to facilitate our right. Too many people in these debates focus on technologies rather than principles.

Comment Re:It is alarming for a judge to say this (Score 1) 584

Yes: and in a very real sense, you've got the facts exactly right and the conclusions exactly wrong.

You have the right to keep and bear arms. That right exists independent of technological developments. If you had instead, say, the right to keep and bear a flintlock pistol, then the instant cap-and-ball revolvers were developed you'd be unable to use them. Flintlocks, cap-and-ball, semiautomatics, the whole nine yards, are technologies that implement one of your natural rights: but your right is to keep and bear arms, not to keep and bear only the technologies of a given time.

In a similar vein, you have no right to a secret ballot. Your right is to have a say in participatory democracy via the voting process. The secret ballot, like the absentee ballot and the public ballot, are all technologies that exist to implement your right. You really don't want a Constitutional guarantee of a secret ballot, because then you'd be unable to use absentee ballots, nor would you be able to use new technologies yet to be developed that are superior to the secret ballot. Requiring, "All Americans have a Constitutional right to a secret ballot," is really not that far from, "All Americans have a Constitutional right to a flintlock pistol." It confuses a technology meant to facilitate the exercise of a right with the right itself.

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