So, here's the deal, since no one reads this anyway, sends me email, whatever, this seems pretty safe.
A long, long time ago when I was a lot younger, I went about the world, seeding the ground in a number of places, with a supply or iridium I just happened to have around (a different story altogether).
This of course, lead Luis Alvarez and others when they finally found evidence of this, to logically conclude that this was all a result of an asteroid collision, leading to the Chicxulub crater and the subsequent extinction of a large percentage of the 'dinosaurs.' In actuality, it was really IMHO a pretty funny joke.
But now that I'm almost 70 million years old, I felt it was time to share this with the precisely zero (0) people who read this.
Regards.
Wednesday, June 30, 2010
Sunday, June 20, 2010
.45ACP
The new one.
Single-stack .45ACP 1911-type, from STI: Trojan 5.0
(http://www.stiguns.com/guns/Trojan5.0/Trojan50.php)
Custom work (hard chrome plating, fiber optic sights, etc. by the best gunsmith
I know: Bob Cogan at Accurate Plating And Weaponry
(http://www.apwcogan.com/)
Call Jason Selva -- the office manager, or Bob himself.
If you own a handgun, everyone has to have a 1911. It's a rule.
Single-stack .45ACP 1911-type, from STI: Trojan 5.0
(http://www.stiguns.com/guns/Trojan5.0/Trojan50.php)
Custom work (hard chrome plating, fiber optic sights, etc. by the best gunsmith
I know: Bob Cogan at Accurate Plating And Weaponry
(http://www.apwcogan.com/)
Call Jason Selva -- the office manager, or Bob himself.
Sunday, June 13, 2010
New Zen-like laser produces pico-second bursts of ... nothing.
In an advance that sounds almost Zen, researchers at the National Institute of Standards and Technology and JILA, a joint institute of NIST and the University of Colorado at Boulder, have demonstrated a new type of pulsed laser that excels at not producing light. The new device generates sustained streams of "dark pulses" -- repeated dips in light intensity -- which is the opposite of the bright bursts in a typical pulsed laser.
("stand back, or I shall fire 60 trillionths of second of darkness at you...")
("stand back, or I shall fire 60 trillionths of second of darkness at you...")
Thursday, June 3, 2010
The Trouble With Boys (statistically speaking) WARNING! Contains mathematics
Probability and statistics are mind-confusing at times, even for those who work with them all the time.
Gary Foshee, a collector and designer of puzzles from Issaquah near Seattle walked to the lectern to present his talk. It consisted of the following three sentences:
"I have two children. One is a boy born on a Tuesday. What is the probability I have two boys?"
"The first thing you think is 'What has Tuesday got to do with it?'" said Foshee, deadpan. "Well, it has everything to do with it." And then he stepped down from the stage.
This is actually a very difficult question, made fascinating by the 'what the heck does Tuesday have to do with the result???"
Foshee's "boy born on a Tuesday" problem is a gem of the genre: easy to state, understandable to the layperson, yet with a completely counter-intuitive answer that can leave you with a smile on your face for days. If you have two children, and one is a boy, then the probability of having two boys is significantly different if you supply the extra information that the boy was born on a Tuesday. I'm not kidding.
Preliminary question: "I have two children. One of them is a boy. What is the probability I have two boys?"
This is a much easier question, though a controversial one. After the gathering ended, Foshee's Tuesday boy problem became a hotly discussed topic on blogs around the world. The main bone of contention was how to properly interpret the question. The way Foshee meant it is, of all the families with one boy and exactly one other child, what proportion of those families have two boys? :)
To answer the question you need to first look at all the equally likely combinations of two children it is possible to have: BG, GB, BB or GG. The question states that one child is a boy. So we can eliminate the GG, leaving us with just three options: BG, GB and BB. One out of these three scenarios is BB, so the probability of the two boys is 1/3 (not 1/2 as seems intuitive). No big problem here, but then the fun begins:
Now we can repeat this technique for the original question. Let's list the equally likely possibilities of children, together with the days of the week they are born in. Let's call a boy born on a Tuesday a BTu. Our possible situations are:
■When the first child is a BTu and the second is a girl born on any day of the week: there are seven different possibilities.
■When the first child is a girl born on any day of the week and the second is a BTu: again, there are seven different possibilities.
■When the first child is a BTu and the second is a boy born on any day of the week: again there are seven different possibilities.
■Finally, there is the situation in which the first child is a boy born on any day of the week and the second child is a BTu – and this is where it gets interesting. There are seven different possibilities here too, but one of them – when both boys are born on a Tuesday – has already been counted when we considered the first to be a BTu and the second on any day of the week. So, since we are counting equally likely possibilities, we can only find an extra six possibilities here. To calculate probababilities, you can't double up on this stuff. :)
Summing up the totals, there are 7 + 7 + 7 + 6 = 27 different equally likely combinations of children with specified gender and birth day, and 13 of these combinations are two boys. So the answer is 13/27, which is very different from 1/3.
It seems remarkable that the probability of having two boys changes from 1/3 to 13/27 when the birth day of one boy is stated – yet it does, and it's quite a generous difference at that. In fact, if you repeat the question but specify a trait rarer than 1/7 the closer the probability will approach 1/2.
Life is strange...
Gary Foshee, a collector and designer of puzzles from Issaquah near Seattle walked to the lectern to present his talk. It consisted of the following three sentences:
"I have two children. One is a boy born on a Tuesday. What is the probability I have two boys?"
"The first thing you think is 'What has Tuesday got to do with it?'" said Foshee, deadpan. "Well, it has everything to do with it." And then he stepped down from the stage.
This is actually a very difficult question, made fascinating by the 'what the heck does Tuesday have to do with the result???"
Foshee's "boy born on a Tuesday" problem is a gem of the genre: easy to state, understandable to the layperson, yet with a completely counter-intuitive answer that can leave you with a smile on your face for days. If you have two children, and one is a boy, then the probability of having two boys is significantly different if you supply the extra information that the boy was born on a Tuesday. I'm not kidding.
Preliminary question: "I have two children. One of them is a boy. What is the probability I have two boys?"
This is a much easier question, though a controversial one. After the gathering ended, Foshee's Tuesday boy problem became a hotly discussed topic on blogs around the world. The main bone of contention was how to properly interpret the question. The way Foshee meant it is, of all the families with one boy and exactly one other child, what proportion of those families have two boys? :)
To answer the question you need to first look at all the equally likely combinations of two children it is possible to have: BG, GB, BB or GG. The question states that one child is a boy. So we can eliminate the GG, leaving us with just three options: BG, GB and BB. One out of these three scenarios is BB, so the probability of the two boys is 1/3 (not 1/2 as seems intuitive). No big problem here, but then the fun begins:
Now we can repeat this technique for the original question. Let's list the equally likely possibilities of children, together with the days of the week they are born in. Let's call a boy born on a Tuesday a BTu. Our possible situations are:
■When the first child is a BTu and the second is a girl born on any day of the week: there are seven different possibilities.
■When the first child is a girl born on any day of the week and the second is a BTu: again, there are seven different possibilities.
■When the first child is a BTu and the second is a boy born on any day of the week: again there are seven different possibilities.
■Finally, there is the situation in which the first child is a boy born on any day of the week and the second child is a BTu – and this is where it gets interesting. There are seven different possibilities here too, but one of them – when both boys are born on a Tuesday – has already been counted when we considered the first to be a BTu and the second on any day of the week. So, since we are counting equally likely possibilities, we can only find an extra six possibilities here. To calculate probababilities, you can't double up on this stuff. :)
Summing up the totals, there are 7 + 7 + 7 + 6 = 27 different equally likely combinations of children with specified gender and birth day, and 13 of these combinations are two boys. So the answer is 13/27, which is very different from 1/3.
It seems remarkable that the probability of having two boys changes from 1/3 to 13/27 when the birth day of one boy is stated – yet it does, and it's quite a generous difference at that. In fact, if you repeat the question but specify a trait rarer than 1/7 the closer the probability will approach 1/2.
Life is strange...
Tuesday, June 1, 2010
Neutrino oscillations confirmed (like you care? read on...)
So, "Researchers on the OPERA experiment at the INFN1's Gran Sasso laboratory in Italy today announced the first direct observation of a tau particle in a muon neutrino beam sent through the Earth from CERN2, 730 km away. This is a significant result, providing the final missing piece of a puzzle that has been challenging science since the 1960s, and giving tantalizing hints of new physics to come."
Anyway for a long time scientists knew that neutrinos (presumably massless particles and thus really really hard to detect and measure) were produced in great quantities in our Sun; but the amounts and ratios of the different kinds differed radically from what was predicted. A presumptive explanation was that some neutrinos changed type (from muon to tau neutrinos) due to an unknown and unexplained mechanism. On May 31 of this year, the 'oscillation' (change of type) of neutrinos was specifically observed and recorded, involving a wholly-muon-type neutrino beam fired from CERN in Switzerland to a detector in Italy.
The confirmation of this oscillation is signficant because the mainstream theory of 'how things are in the universe' and the most detailed, confirmed, measured and most predictive theory ever conceived by man and arguably mankind's greatest achievement -- the 'Standard Model' -- does not and cannot explain this. Neutrinos have always been considered 'massless' particles like photons, and the oscillation of such particles is prohibited in the Standard Model. So, our understanding of the universe and how it works, needs revision; this result and the revelations concerning the existence and effects of both 'dark matter' and 'dark energy' mean that the Standard Model needs to be redefined or replaced. The problem is, no one knows now what form or structure such a replacement might be. In the physics world, these are 'interesting times' indeed.
Anyway for a long time scientists knew that neutrinos (presumably massless particles and thus really really hard to detect and measure) were produced in great quantities in our Sun; but the amounts and ratios of the different kinds differed radically from what was predicted. A presumptive explanation was that some neutrinos changed type (from muon to tau neutrinos) due to an unknown and unexplained mechanism. On May 31 of this year, the 'oscillation' (change of type) of neutrinos was specifically observed and recorded, involving a wholly-muon-type neutrino beam fired from CERN in Switzerland to a detector in Italy.
The confirmation of this oscillation is signficant because the mainstream theory of 'how things are in the universe' and the most detailed, confirmed, measured and most predictive theory ever conceived by man and arguably mankind's greatest achievement -- the 'Standard Model' -- does not and cannot explain this. Neutrinos have always been considered 'massless' particles like photons, and the oscillation of such particles is prohibited in the Standard Model. So, our understanding of the universe and how it works, needs revision; this result and the revelations concerning the existence and effects of both 'dark matter' and 'dark energy' mean that the Standard Model needs to be redefined or replaced. The problem is, no one knows now what form or structure such a replacement might be. In the physics world, these are 'interesting times' indeed.
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