Friday, October 26, 2007
Cocktail Party Physics
Awesome website with some of the most insightful commentary on physics I have seen in a long time.
Dubious Moments in Comic Book History
From Lileks. Say what you want about his politics, he's a often hilarious on culture.
Dark Matters
As long time readers know, I am not wholly convinced about the existance of Dark Matter, and favor a more intuitive approach that modifies gravity at large distances.
Another log on that fire can be read here
A detailed analysis of the November 15, 2006 data release (Clowe et al., 2006) X-ray surface density Sigma-map and the strong and weak gravitational lensing convergence kappa-map for the Bullet Cluster 1E0657-558 is performed and the results are compared with the predictions of a modified gravity (MOG) and dark matter. Our surface density Sigma-model is computed using a King beta-model density, and a mass profile of the main cluster and an isothermal temperature profile are determined by the MOG. We find that the main cluster thermal profile is nearly isothermal. The MOG prediction of the isothermal temperature of the main cluster is T = 15.5 +- 3.9 keV, in good agreement with the experimental value T = 14.8{+2.0}{-1.7} keV. Excellent fits to the two-dimensional convergence kappa-map data are obtained without non-baryonic dark matter, accounting for the 8-sigma spatial offset between the Sigma-map and the kappa-map reported in Clowe et al. (2006). The MOG prediction for the kappa-map results in two baryonic components distributed across the Bullet Cluster 1E0657-558 with averaged mass-fraction of 83% intracluster medium (ICM) gas and 17% galaxies. Conversely, the Newtonian dark matter kappa-model has on average 76% dark matter (neglecting the indeterminant contribution due to the galaxies) and 24% ICM gas for a baryon to dark matter mass-fraction of 0.32, a statistically significant result when compared to the predicted Lambda-CDM cosmological baryon mass-fraction of 0.176{+0.019}{-0.012} (Spergel et al., 2006).
Another log on that fire can be read here
A detailed analysis of the November 15, 2006 data release (Clowe et al., 2006) X-ray surface density Sigma-map and the strong and weak gravitational lensing convergence kappa-map for the Bullet Cluster 1E0657-558 is performed and the results are compared with the predictions of a modified gravity (MOG) and dark matter. Our surface density Sigma-model is computed using a King beta-model density, and a mass profile of the main cluster and an isothermal temperature profile are determined by the MOG. We find that the main cluster thermal profile is nearly isothermal. The MOG prediction of the isothermal temperature of the main cluster is T = 15.5 +- 3.9 keV, in good agreement with the experimental value T = 14.8{+2.0}{-1.7} keV. Excellent fits to the two-dimensional convergence kappa-map data are obtained without non-baryonic dark matter, accounting for the 8-sigma spatial offset between the Sigma-map and the kappa-map reported in Clowe et al. (2006). The MOG prediction for the kappa-map results in two baryonic components distributed across the Bullet Cluster 1E0657-558 with averaged mass-fraction of 83% intracluster medium (ICM) gas and 17% galaxies. Conversely, the Newtonian dark matter kappa-model has on average 76% dark matter (neglecting the indeterminant contribution due to the galaxies) and 24% ICM gas for a baryon to dark matter mass-fraction of 0.32, a statistically significant result when compared to the predicted Lambda-CDM cosmological baryon mass-fraction of 0.176{+0.019}{-0.012} (Spergel et al., 2006).
Comet Holmes in Outburst
Something to do this weekend, if the skies are clear:
Comet 17P/Holmes stunned comet watchers across planet Earth earlier this week. On October 24, it increased in brightness over half a million times in a matter of hours. The outburst transformed it from an obscure and faint comet quietly orbiting the Sun with a period of about 7 years to a naked-eye comet rivaling the brighter stars in the constellation Perseus. Recorded on that date, this view from Tehran, Iran highlights the comet's (enhanced and circled) dramatic new visibility in urban skies. The inset (left) is a telescopic image from a backyard in Buffalo, New York showing the comet's greatly expanded coma, but apparent lack of a tail. Holmes' outburst could be due to a sudden exposure of fresh cometary ice or even the breakup of the comet nucleus. The comet may well remain bright in the coming days.
Comet 17P/Holmes stunned comet watchers across planet Earth earlier this week. On October 24, it increased in brightness over half a million times in a matter of hours. The outburst transformed it from an obscure and faint comet quietly orbiting the Sun with a period of about 7 years to a naked-eye comet rivaling the brighter stars in the constellation Perseus. Recorded on that date, this view from Tehran, Iran highlights the comet's (enhanced and circled) dramatic new visibility in urban skies. The inset (left) is a telescopic image from a backyard in Buffalo, New York showing the comet's greatly expanded coma, but apparent lack of a tail. Holmes' outburst could be due to a sudden exposure of fresh cometary ice or even the breakup of the comet nucleus. The comet may well remain bright in the coming days.
Thursday, October 25, 2007
Fanning the Flames of Fear
More on how folks like Fox take a second rate threat who got lucky, and tried to turn him into the boggy man.
Did al Qaeda start the California wildfires?
As more than a million people escaped the flames, Fox News anchors couldn't help speculating about a terrorism link to the blazes ravaging southern California.
"I've heard some people talk about this a little bit to me, but have you heard anybody suggest that this could be some form of terrorism," Fox & Friends co-host Steve Doocy asked Wednesday morning.
Correspondent Adam Housley said he's received "hundreds of comments" from readers of his Fox News blog speculating about a link to terrorism.
At some point, even the most ardent support has to admit that what they do on Fox isn't news.
Did al Qaeda start the California wildfires?
As more than a million people escaped the flames, Fox News anchors couldn't help speculating about a terrorism link to the blazes ravaging southern California.
"I've heard some people talk about this a little bit to me, but have you heard anybody suggest that this could be some form of terrorism," Fox & Friends co-host Steve Doocy asked Wednesday morning.
Correspondent Adam Housley said he's received "hundreds of comments" from readers of his Fox News blog speculating about a link to terrorism.
At some point, even the most ardent support has to admit that what they do on Fox isn't news.
David Gerrold has a Blog
here
David is one of my favorite authors and wrote The Man Who Folded Himself, which irrevocably warped me when I read it at age 13 (it's a fable on the dangers of narcissism).
His novel, the Martian Child, has been made into a movie and is coming out in the next few weeks.
David is one of my favorite authors and wrote The Man Who Folded Himself, which irrevocably warped me when I read it at age 13 (it's a fable on the dangers of narcissism).
His novel, the Martian Child, has been made into a movie and is coming out in the next few weeks.
Wednesday, October 24, 2007
World Net Daily
Did you know the Earth is only 6010 years old? Did you know that atheists are the greatest threat to our Christian nation. You're obviously not reading World Net Daily!
Also, this little gem:
"How to outlaw Christianity" by Chuck Norris, who says 30 million Americans profess there is no God, and shows how atheist organizations are working to undermine Christianity .
(via)
Also, this little gem:
"How to outlaw Christianity" by Chuck Norris, who says 30 million Americans profess there is no God, and shows how atheist organizations are working to undermine Christianity .
(via)
Tuesday, October 23, 2007
Another Reason to Root for the Red Sox
Does this mean, if the Sox take the trophy, god doesn't exist?
"You look at some of the moves we made and didn't make," general manager Dan O'Dowd said in the only interview he has given on the subject, long before the Rockies' remarkable ascension over the past few weeks. "You look at some of the games we're winning. Those aren't just a coincidence. God has definitely had a hand in this."
Anyone who fancies the Almighty has better things to do than determine the outcome of baseball games might want to consider just what the Rockies have achieved. At the beginning of September, they were fourth out of five in the National League Western division and seemingly headed to yet another cold Colorado winter chewing over another disappointing season. Then they started winning, and didn't stop. They won 13 of their last 14 regular-season games – a freak occurrence in a sport that has always been more about failure than success, where even the strongest teams usually win no more than six games of every 10.
(here)
"You look at some of the moves we made and didn't make," general manager Dan O'Dowd said in the only interview he has given on the subject, long before the Rockies' remarkable ascension over the past few weeks. "You look at some of the games we're winning. Those aren't just a coincidence. God has definitely had a hand in this."
Anyone who fancies the Almighty has better things to do than determine the outcome of baseball games might want to consider just what the Rockies have achieved. At the beginning of September, they were fourth out of five in the National League Western division and seemingly headed to yet another cold Colorado winter chewing over another disappointing season. Then they started winning, and didn't stop. They won 13 of their last 14 regular-season games – a freak occurrence in a sport that has always been more about failure than success, where even the strongest teams usually win no more than six games of every 10.
(here)
Monday, October 22, 2007
Probably
It's probably against some policy at work to use a phrase like "I already have the vision thing worked out and will sibmit it 6 weeks early. The rest will be [person X] trying to get a hand job from Accenture."
That doesnt' make it untrue.
That doesnt' make it untrue.
Something About Cats I Did Not Know This Morning
...and I am reminded of the motto of Transylvania Polytechnic University, "Knowledge Brings Fear"
Sunday, October 21, 2007
What's the Word I am Looking For??
"Crushed" I think will fit the bill.
11-2, Yikes!
If Susan were alive today, I'm sure she would be jumping up and down about it. As it is, I didn't care too much about it until I heard from a co-worker they were in the play-offs. As he is a Cleveland fan, I sensed an opportunity for some gain and bet $100 on Boston
"You realize Cleveland is ahead 2 games to 1", he said.
"Yes, but if they can be down 3-0 against the Yankees and win, they can do anything."
"Okay, it's your loss..."
and thus a bet was made.
Tonight's dialog:
"Smell that? It smells like Victory!"
"Smells like ... shut up."
"I'm just glad I finally made a bet that doesn't end up with me mowing someone's lawn in a wedding dress..."
11-2, Yikes!
If Susan were alive today, I'm sure she would be jumping up and down about it. As it is, I didn't care too much about it until I heard from a co-worker they were in the play-offs. As he is a Cleveland fan, I sensed an opportunity for some gain and bet $100 on Boston
"You realize Cleveland is ahead 2 games to 1", he said.
"Yes, but if they can be down 3-0 against the Yankees and win, they can do anything."
"Okay, it's your loss..."
and thus a bet was made.
Tonight's dialog:
"Smell that? It smells like Victory!"
"Smells like ... shut up."
"I'm just glad I finally made a bet that doesn't end up with me mowing someone's lawn in a wedding dress..."
Speaking of the Universe
PZ Myers talks about a question he was asked, "What is the purpose of the universe?". My first reaction was, "that's a nonsense question, the universe is a natural phenomenon, it doesn't have a 'purpose'". PZ does one better though
Near as I can tell, the primary purposes of the universe as discerned from the casual expressions of religion's proponents are 1) to bias victory in local football games, and 2) to regulate the appropriate orifices into which certain people are allowed to place their penises. How the creation of Betelgeuse, the concentration of planetary material in our solar system in one body which we can't reach and which is uninhabitable to us, and the ubiquity and success of bacteria all play into these purposes is unknown to me … it must be one of God's mysteries.
Near as I can tell, the primary purposes of the universe as discerned from the casual expressions of religion's proponents are 1) to bias victory in local football games, and 2) to regulate the appropriate orifices into which certain people are allowed to place their penises. How the creation of Betelgeuse, the concentration of planetary material in our solar system in one body which we can't reach and which is uninhabitable to us, and the ubiquity and success of bacteria all play into these purposes is unknown to me … it must be one of God's mysteries.
The Big Rip
When I was a kid and, in fact most of the way through grad school, the Standard Model held the universe was going to end in a cyclic "Big Crunch", the reset button would be pushed, and a new universe would be created. It smacked of such elegance that everyone assumed it would be true once the evidence came in. Some in the spiritual community even held that it was evidence of an intelligent designer, or of a vindication of the wisdom of past thinkers.
It seems we were all way, way wrong on this one.
Cosmologists have long wondered whether the Universe will eventually re-collapse and end with a Big Crunch, or expand forever, becoming increasingly cold and empty. Recent evidence for a flat Universe, possibly with a cosmological constant or some other sort of negative-pressure dark energy, has suggested that our fate is the latter. However, the data may actually be pointing toward an astonishingly different cosmic end game. Here, we explore the consequences that follow if the dark energy is phantom energy, in which the sum of the pressure and energy density is negative. The positive phantom-energy density becomes infinite in finite time, overcoming all other forms of matter, such that the gravitational repulsion rapidly brings our brief epoch of cosmic structure to a close. The phantom energy rips apart the Milky Way, solar system, Earth, and ultimately the molecules, atoms, nuclei, and nucleons of which we are composed, before the death of the Universe in a ``Big Rip''.
In other words, the universe is an exploding bomb and we are trapped inside.
Full paper here, a good read on a Sunday afternoon.
It seems we were all way, way wrong on this one.
Cosmologists have long wondered whether the Universe will eventually re-collapse and end with a Big Crunch, or expand forever, becoming increasingly cold and empty. Recent evidence for a flat Universe, possibly with a cosmological constant or some other sort of negative-pressure dark energy, has suggested that our fate is the latter. However, the data may actually be pointing toward an astonishingly different cosmic end game. Here, we explore the consequences that follow if the dark energy is phantom energy, in which the sum of the pressure and energy density is negative. The positive phantom-energy density becomes infinite in finite time, overcoming all other forms of matter, such that the gravitational repulsion rapidly brings our brief epoch of cosmic structure to a close. The phantom energy rips apart the Milky Way, solar system, Earth, and ultimately the molecules, atoms, nuclei, and nucleons of which we are composed, before the death of the Universe in a ``Big Rip''.
In other words, the universe is an exploding bomb and we are trapped inside.
Full paper here, a good read on a Sunday afternoon.
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