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Concern Over Creating Black Holes
Maria Williams writes to tell us about worry surrounding the impending startup of CERN's Large Hadron Collider. Some fear that the device, in creating mini black holes, could jeopardize Life As We Know It. While the tiny black holes should evaporate quickly — throwing off so-called Hawking radiation that can be detected — CERN software developer Ran Livneh reminds us that "Any physicist will tell you that there is no way to prove that generated black holes will decay." The LHC site assures us there's nothing to worry about. The flap is reminiscent of the time the Relativistic Heavy Ion Collider went live. The worry then was that "negative strangelets" could gobble up the world.
Some scientists were very concerned the first atomic bomb would produce so much heat it would ignite the atmosphere and burn the entire surface of the earth. Fortunately it didn't happen. But it's good that people bring up these ideas so we challenge assumptions and try to be safe while still advancing science.
Developers: We can use your help.
Edward Teller speculated that an atomic weapon could ignite the atmosphere. Another physicist discredited and disproved the idea, but the fear wasn't laid to rest until the actual weapons were used.
http://en.wikipedia.org/wiki/Manhattan_Project (wikipedia, blah blah blah)
Cthulhu Saves.
Primary cosmic rays impact the earth all the time, and these often have far higher energies than even our largest particle accelerators are capable of producing. For any experiment we attempt, we can be reasonably sure that colliding cosmic rays have already produced the same results, sometime within the past few billions years. If we could create massively destructive black holes through our particle accelerators, one would expect that stray cosmic rays would have already done so.
This type of fear occurred many times during the nuclear physics history, when higher and higher energies were explored. The answer against fears of unknown catastrophic effect has been that some cosmic rays are much more energetic than any artificially accelerated particles (10^21 eV for some cosmic rays in comparison to the feeble 10^12 eV in today accelerators such as LHC). For sure the Earth and the Sun did already receive zillons of cosmic rays without disappearing...
False.
A black hole cannot just "suck in" whatever it wants, the matter and energy in question must physically come in contact with the boundary of the body to begin with. Note that no object in the immediate vicinity of a newly formed black hole has its orbit disturbed in any significant way. The gravity of a black hole to anything standing outside its bounds is not particularly fascinating - they do not behave like a drain, contrary to the way they're usually drawn.
The holes being created (IF they even get created) would be so incredibly tiny that they would immediately be attracted to the core of the planet, happily flying right in between molecules and even atoms, only occasionally colliding with them and obtaining their mass.
If, by chance, they are wrong about the decay and one escapes, it could take much longer than you or I need to worry about it until it becomes massive enough (density != mass!) to destroy the planet.
Of course, while we're speculating on silly doomsday scenarios, it could also randomly collide fast enough to grow at an exponential rate and destroy us all nearly instantaneously.
That's not too likely either though.
It's the mass packed into a certain volume that matters. You can have all of the mass in a galaxy, but if it's spread out over the volume of a typical galaxy, you have no black hole. Once you pack it into a certain density, you reach a point where the local gravity becomes strong enough that light cannot escape. I haven't read TFA, but it seems clear that they aren't trying to pack a bunch of mass to create a "tiny" or "microscopic" black hole. They're colliding exceedingly small amounts of mass into an exceptionally small area. Billions of times smaller than "microscopic".
Unless our understanding of gravity is WAY off here, there's nothing special about this region of space except that we have a bunch of mass compressed into a small area. The black hole has no chance of affecting us because the mass that makes it up is no greater than the mass we put into it. Unless we seriously misunderstand gravity, this thing will disappear instantly because it can't hope to sustain itself.
I think microscopic black holes couldn't eat up the earth due to the three stooges problem. They are so small that only an atom at a time can get in, but the gravity is strong enough to try to suck in more, so all the atoms get bunched up around the event horizon like the three stooges all trying to get through a door at the same time.
Fortunately, I don't have a sense of humor. This allows me to point out that, in theory anyhow (I've never seen one in person), all black holes are the same size. Their mass may vary, their size does not.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
I don't know how old Hogan's book is, but in 1990 or so David Brin wrote
Earth
where an artificial black hole grows out of control and slowly eats the planet earth from the inside out.
Thats Fermi's Paradox!:
h tml
"The story goes that, one day back on the 1940's, a group of atomic scientists, including the famous Enrico Fermi, were sitting around talking, when the subject turned to extraterrestrial life. Fermi is supposed to have then asked, "So? Where is everybody?" What he meant was: If there are all these billions of planets in the universe that are capable of supporting life, and millions of intelligent species out there, then how come none has visited earth? This has come to be known as The Fermi Paradox.
Fermi realized that any civilization with a modest amount of rocket technology and an immodest amount of imperial incentive could rapidly colonize the entire Galaxy. Within a few million years, every star system could be brought under the wing of empire. A few million years may sound long, but in fact it's quite short compared with the age of the Galaxy, which is roughly ten thousand million years. Colonization of the Milky Way should be a quick exercise."
http://zebu.uoregon.edu/~js/cosmo/lectures/lec28.
http://en.wikipedia.org/wiki/Fermi_paradox
Reminds me of the boot Thrice Upon a Time by James P. Hogan where one of the scenarios is the world is destroyed by a CERN fusion generators that uses inertial confinement and ends up producing mini black holes as a byproduct.
We don't see the world as it is, we see it as we are.
-- Anais Nin
In the 1860s, the Democrats were the conservatives and the Republicans were the "liberals." Things got turned around in early part of the 20th century when Taft repudiated many of the progressive principles that helped Teddy Roosevelt win election to the Vice Presidency (and later to the Presidency). This annoyed Roosevelt so much that he ran against Taft on the Progressive Party ("Bull Moose") ticket; but the two split the vote allowing Wilson to be elected. In many ways, Wilson set the stage for what would become Democratic (Party) foreign policy for the rest of the century in his proposals for the Peace of Versailles and the creation of the League of Nations; on the other hand, there's a lot of dispute about his attitude toward civil rights and "race" in America. However, the turning point for the Democratic Party from what we might call "conservative" to what we might call "liberal" was the Great Depression, the New Deal policies of the Franklin Delano Roosevelt administration, the integration of the Army under Truman, and the split of the Dixiecrats in 1948 (and subsequent switch of many segregationists to the Republican Party in 1964 after Johnson's support of desegregation). While it is not quite possible to map anti-slavery and pro-Civil Rights sentiment together as either "liberal" or "progressive," it is possible to locate both sentiments in "anti-conservative" movements and also to see them as at least tenuously related.
Low-mass black holes should, theoretically have sub-fennoscopic event horizons.
So?
Well, the event-sphere is actually small enough to fit between two atoms and not even touch their electrons. If the black-hole passed through the earth, it would come out the other side with about half velocity and about twice its original mass. And that's only if Hawking radiation is fallacious. If it's not, then the black hole will only have an event horizon until the decrease in mass causes its schwartzchild radius to drop below its volumetric radius - at which point, it's not a black hole anymore, it's just shitlessly dense regula-ass matter.
110100 1101000 1101000 1100110 0 1101111 1101000 1100011 1
Back then, the "republican" conservatives opposed the expansion of slavery and made freeing the slaves a goal. I believe they actually won the election before the civil war. Techically, Lincoln started out as a "whig", although by then the whig party was split along pro-slave/anti-slave lines and most of the anti-slave whigs (including Lincoln) became republicans by the time of the election.
Often, the pro-slave ex-whigs called themselves the "conservatives" (in an attempt to reconcile the whig party), but they mostly just teamed up with the democrats in the south and of course the democrats lost that antebellum election and the conservative "republicans" won.
Perhaps you can make the case that technically the north-conservatives won and the south-conservatives lost, but I don't think that makes your case...
It was actually a short story by Isaac Asimov titled "The Last Question" - http://en.wikipedia.org/wiki/The_Last_Question
. htm
You can also read it online: http://infohost.nmt.edu/~mlindsey/asimov/question
While something travelling that fast has little probability of interacting with anything
On the contrary, even though the particle was traveling that fast, it interacted with the thin upper atmosphere, right? Isn't that where the telescope was looking to see the flashes?
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Please don't confuse the historical meaning of the word "Progressive" with its contemporary political usage. The term has a fairly exact historical meaning and describes a specific political and social movement in American politics. Political reform, the conservation movement, the protection of consumers, and the restraint of corporate power were the central elements of the Progressive Movement. TR was a progressive. He proposed or supported legislation in each of these areas. There's no getting around it. Any serious American historian will tell you that both political parties during this era (from the end of the Civil War to World War I) had their progressive wings. The first post in this thread got it right.
You made two mistakes. First, you want to impose your own ideas onto the past, rather than understand the past. Second, you wish to overly simplify the past. Believe me, the Progressive Era (or the first century AD, or medieval Europe) was just as complicated, the politics just as confusing, as it is today. Humans are complicated creatures, no matter where or when you find them. The progressives were united by their common desire to see reform and fairness in American life. How this might be accomplished ran the entire spectrum, from more conservative individuals who only wanted to tinker around at the edges, to those who wanted to overthrow the entire system. Nothing in human history is simple enough to fit inside your black and white world view. Maybe you should add a little color to your thoughts.