This is a rather fascinating paper (at least to me) that studies the mechanism of an electric breakdown. While the occurrence of static electricity is common when you feel a spark between your hand and a doorknob, trying to get the exactly, step-by-step mechanism is not easy. This is especially true in trying to get a clear, direct experimental verification of all the different models of breakdown, because such an effect is very transient and occurs over such a short period of time. Even trying to sample the field with a probe would not work because the probe itself will alter the field that we are trying to measure.
This issue has quite a bit of relevance to the news story about the International Linear Collider. One of the main issues on any accelerator is the maximum electric field gradient that an accelerating structure can withstand. It is widely known that the regular copper cavity that is commonly used in many accelerating structures will start experience electric breakdown at fields above 40 MV/m. (This number actually has some variation depending on the RF frequency applied to the cavity and the pulse length). What this means is that to accelerate charged particles to a higher energy, you will need many of these structures, since each one can only have up to some maximum value. The ILC is going to use superconducting technology as its accelerating structure to get a higher gradient. Still, even in a superconducting structure, there is still a maximum gradient that can be applied before breakdown occurs. That's why the ILC is proposed to be 20 km long to achieve its targeted energy.
So understanding the physics of breakdown is crucial in predicting on when it will occur for a particular material and configuration. Knowing such a thing will allow us to investigate how to minimize such a thing, and maybe even try to engineer a material that can have a higher tolerance to high fields.
This is one of the projects that my group is going to do. We're hoping to investigate the onset of electric breakdown in an RF cavity by examining field emission current pattern from a surface before a breakdown. There are many models of breakdown that attribute the heating of protrusions due to a high field emission current as the main trigger of the creation of a plasma that precedes a breakdown. We are hoping to test this via correlating regions of high field emission current (or dark current) with the eventual breakdown. A dedicated facility to study this is being assembled and about 90% done. So hopefully, sometime within the next couple of months, we will start our initial testing.
Zz.
Saturday, February 10, 2007
Friday, February 09, 2007
The Physics of Ribbon Curling
I kid you not!
Next time you look at those curled up ribbons at the end of a neatly-tied bow, you'll know that the physics of it has been a mystery till now. A physicist at Harvard claims to have figured it out, and lest you think this is purely an exercise in triviality, you'd be wrong. It seems that this knowledge may have some relevance to a new field of manufacturing, including nanotechnology!
Zz.
Next time you look at those curled up ribbons at the end of a neatly-tied bow, you'll know that the physics of it has been a mystery till now. A physicist at Harvard claims to have figured it out, and lest you think this is purely an exercise in triviality, you'd be wrong. It seems that this knowledge may have some relevance to a new field of manufacturing, including nanotechnology!
Zz.
More on the ILC Cost
Most press reports on the announcement of the cost for the International Linear Collider do not include the breakdown of where these costs come from. The rough estimate of the various components are as follows:
M&S/equipment for machine: $4.9B
Conventional facilities: $1.8B
Manpower: 13000 FTE's (full time employee/effort)
Construction time: 7 years
Again, remember that these are quoted in 2007 dollars.
This is certainly a huge project and will require a well-managed international effort. The only question now is (i) where will it be located and (ii) when will it be built. Any delay in deciding this will only drive it its costs, something many people (and countries) can't afford.
Zz.
M&S/equipment for machine: $4.9B
Conventional facilities: $1.8B
Manpower: 13000 FTE's (full time employee/effort)
Construction time: 7 years
Again, remember that these are quoted in 2007 dollars.
This is certainly a huge project and will require a well-managed international effort. The only question now is (i) where will it be located and (ii) when will it be built. Any delay in deciding this will only drive it its costs, something many people (and countries) can't afford.
Zz.
Thursday, February 08, 2007
ILC to Cost $6.7 Billion
It has been formally announced that the International Linear Collider will cost $6.7 billion in terms of FY2007 dollars.
Yes, it is a shipload of change.
For the US high energy physics community, this is the ONLY project that they are pushing to host right now on US soil. The Tevatron, as have been mentioned earlier, will cease operation at the end of 2009. After that, there will be no high energy physics collider experiment in the US. Several institutions, including Fermilab and Argonne, are trying to get support for ILC to be built at Fermilab by incorporating the existing facilities into the new design. I'm guessing that people in Texas have learned their lessons from the failed SSC and won't try to bid for this again.
To me, the only serious competition to the US in hosting the ILC is China. With almost unlimited financial resources and the hunger to be a more important player in the international scientific scene, they will be a very serious and viable candidate to host such a facility. The fact that this announcement is made during a meeting in China is not a mere coincidence.
Zz.
Yes, it is a shipload of change.
For the US high energy physics community, this is the ONLY project that they are pushing to host right now on US soil. The Tevatron, as have been mentioned earlier, will cease operation at the end of 2009. After that, there will be no high energy physics collider experiment in the US. Several institutions, including Fermilab and Argonne, are trying to get support for ILC to be built at Fermilab by incorporating the existing facilities into the new design. I'm guessing that people in Texas have learned their lessons from the failed SSC and won't try to bid for this again.
To me, the only serious competition to the US in hosting the ILC is China. With almost unlimited financial resources and the hunger to be a more important player in the international scientific scene, they will be a very serious and viable candidate to host such a facility. The fact that this announcement is made during a meeting in China is not a mere coincidence.
Zz.
Follow-up on the bubble Fusion Fiasco
I should have remembered this when I wrote the earlier post on this issue. Brian Naranjo uploaded a rebuttal to the reply made by Taleyarkhan in PRL. Since PRL has a policy that you can't write a comment to a reply, all he can do is either write a whole new paper, or upload his comment to ArXiv, which was what he did just this past Feb. 1, 2007.
While this comment does not address the issue of what Purdue University was investigating, it does support the argument that this bubble fusion phenomenon is far from being confirmed.
Zz.
While this comment does not address the issue of what Purdue University was investigating, it does support the argument that this bubble fusion phenomenon is far from being confirmed.
Zz.
Wednesday, February 07, 2007
Second Inquiry Exonerates Taleyarkhan?
Oh really now?
Supposedly, Purdue University administrators have exonerated Rusi Taleyarkhan of allegations of misconduct in the bubble fusion debacle. Unfortunately, no one knows what was done, what was reviewed, who reviewed it, and how they arrived at such a conclusion. This was done by a secret panel deliberating secretly. In other words, as much as Purdue tries to kill this off, it will not go away, and will continue to be a blemish on the university.
Now, compare this to what Bell Labs did after a similar allegations was leveled at Hendrik Schon a few years ago. Bell appointed a blue-ribbon panel headed by Malcolm Beasley, a very respected physicist from Stanford, and had a very open, full disclosure investigation and findings that were available online. The difference here is night and day!
Whether there was any misconduct at all, at this point, is quite irrelevant. What I do know is that the reputation of Purdue University in terms of integrity is SHOT.
Zz.
Supposedly, Purdue University administrators have exonerated Rusi Taleyarkhan of allegations of misconduct in the bubble fusion debacle. Unfortunately, no one knows what was done, what was reviewed, who reviewed it, and how they arrived at such a conclusion. This was done by a secret panel deliberating secretly. In other words, as much as Purdue tries to kill this off, it will not go away, and will continue to be a blemish on the university.
Now, compare this to what Bell Labs did after a similar allegations was leveled at Hendrik Schon a few years ago. Bell appointed a blue-ribbon panel headed by Malcolm Beasley, a very respected physicist from Stanford, and had a very open, full disclosure investigation and findings that were available online. The difference here is night and day!
Whether there was any misconduct at all, at this point, is quite irrelevant. What I do know is that the reputation of Purdue University in terms of integrity is SHOT.
Zz.
Storing Light Here, and Retrieving It There
Lene Hau and her group are at it again!
After demonstrating a few years ago that they can stop light completely and then turn it back on, they have now exploited another aspect of quantum mechanics. In this new experiment, they have managed to store light in one BEC gas, and then have it retransmitted back using a second BEC gas! This is such a clever experiment.
Zz.
After demonstrating a few years ago that they can stop light completely and then turn it back on, they have now exploited another aspect of quantum mechanics. In this new experiment, they have managed to store light in one BEC gas, and then have it retransmitted back using a second BEC gas! This is such a clever experiment.
Zz.
More on the US FY2007 Budget and Possible 2008 Budget
More information on the proposed Fiscal Year 2007 US Budget that is in the Senate right now, and the proposed FY 2008 Budget. It appears that the NIH may get hit hard with this.
I have a mixed feeling about this. On one hand, I hate to see science budgets being cut, not just for selfish reason, but I know what happens to projects when something like that occurs. Many science research projects take time to develop and mature, and when there is a funding cut, decisions have to be made on what to let go and what to keep. Inevitably, things that just got started and yet to really produce are the ones that tend to go first.
But on the other hand, I've watched with utter envy how, especially during the Clinton Administration, the NIH budget simply bloomed before our very eyes while funding for the physical sciences were barely surviving above water. The NIH at least doubled their funding during that time, while the DOE and NSF's basic science research barely moved. During this time, I know of several physicists who pointed out that many of the abilities and facilities that NIH-type research are able to do were directly benefiting the work done in basic physics research. Facilities like synchrotron centers, SEM technology, etc.. etc.. all came out of basic physics research. There is a trickle down effect here in which things that were part of physics and became well-known from physics are later used in biology, biophysics, biochemistry, and medicine. So to neglect the "source" of all these innovations was simply insane.
So now it appears that the shoe is on the other foot. The NIH budget may, if the President gets his way, suffer a cutback while DOE and NSF's funding on physical science may double in 10 years.
Zz.
I have a mixed feeling about this. On one hand, I hate to see science budgets being cut, not just for selfish reason, but I know what happens to projects when something like that occurs. Many science research projects take time to develop and mature, and when there is a funding cut, decisions have to be made on what to let go and what to keep. Inevitably, things that just got started and yet to really produce are the ones that tend to go first.
But on the other hand, I've watched with utter envy how, especially during the Clinton Administration, the NIH budget simply bloomed before our very eyes while funding for the physical sciences were barely surviving above water. The NIH at least doubled their funding during that time, while the DOE and NSF's basic science research barely moved. During this time, I know of several physicists who pointed out that many of the abilities and facilities that NIH-type research are able to do were directly benefiting the work done in basic physics research. Facilities like synchrotron centers, SEM technology, etc.. etc.. all came out of basic physics research. There is a trickle down effect here in which things that were part of physics and became well-known from physics are later used in biology, biophysics, biochemistry, and medicine. So to neglect the "source" of all these innovations was simply insane.
So now it appears that the shoe is on the other foot. The NIH budget may, if the President gets his way, suffer a cutback while DOE and NSF's funding on physical science may double in 10 years.
Zz.
Tuesday, February 06, 2007
Diamond is Open For Business
The Diamond Light Source, UK's new synchrotron facility, is finally open for business, with the first scientific users expected this week.
Zz.
Zz.
Can Washington Get Smart About Science?
This is an op-ed piece written by Alan Sokal and Chris Mooney. If those names sound familiar to you, then you're up to speed on the situation with how science is done among the academicians and politicians.
Alan Sokal became a physics household name when he did his infamous Sokal Hoax on Social Text journal. In a masterful, ingenious sweep, he revealed the fallacy (and frankly, the utter nonsense) of postmodernist delusion of knowing what science is. It was a perfect attack on how science (and especially physics) was abused by this group of people.
Chris Mooney became well-known due to his article "The Republican War on Science", his attempt to expose how the Republican, after gaining power, tried to either squash, or change, science to suit their personal agenda or beliefs.
So this op-ed piece in LA Times from these two well-known defender of science is VERY hot, so hot that it just sizzles with scathing attack on how science has been mistreated during this past few years. Whether you are a Republican, Democrat, or independent, etc.. this is an essay that should be read because these are points that must be addressed. Whether one agrees with it or not, one fact remains very clear - that there HAS been a deliberate effort to subdue scientific works and results during the Bush administration.
Look, none of us are naive enough to not think that every administration will try to enhance scientific reports that agree with their position. We were not born yesterday, and most of us have enough cynicism in the system to at least be aware of such a thing. However, there have been many evidence that the current administration has done unprecedented actions to stifle scientific results, and even supported the teaching of "intelligent design" in schools. I have seen physicists, who are normally conservative in their politics, completely changing their tunes after seeing what has transpired.
As the article said, it is ironic that the Republican party, that had always tried to promote itself as the champion of science, is now directly at war against it. I also don't doubt that the backlash against religion as evidenced by the popularity of Dawkins book, and the recently released attack on religion by Stenger that I mentioned in the previous post, is a result of the extreme religious fanaticism imposed into the American political and social scene. I think those who are stuck in the middle have very important choices to make.
Zz.
Alan Sokal became a physics household name when he did his infamous Sokal Hoax on Social Text journal. In a masterful, ingenious sweep, he revealed the fallacy (and frankly, the utter nonsense) of postmodernist delusion of knowing what science is. It was a perfect attack on how science (and especially physics) was abused by this group of people.
Chris Mooney became well-known due to his article "The Republican War on Science", his attempt to expose how the Republican, after gaining power, tried to either squash, or change, science to suit their personal agenda or beliefs.
So this op-ed piece in LA Times from these two well-known defender of science is VERY hot, so hot that it just sizzles with scathing attack on how science has been mistreated during this past few years. Whether you are a Republican, Democrat, or independent, etc.. this is an essay that should be read because these are points that must be addressed. Whether one agrees with it or not, one fact remains very clear - that there HAS been a deliberate effort to subdue scientific works and results during the Bush administration.
Look, none of us are naive enough to not think that every administration will try to enhance scientific reports that agree with their position. We were not born yesterday, and most of us have enough cynicism in the system to at least be aware of such a thing. However, there have been many evidence that the current administration has done unprecedented actions to stifle scientific results, and even supported the teaching of "intelligent design" in schools. I have seen physicists, who are normally conservative in their politics, completely changing their tunes after seeing what has transpired.
As the article said, it is ironic that the Republican party, that had always tried to promote itself as the champion of science, is now directly at war against it. I also don't doubt that the backlash against religion as evidenced by the popularity of Dawkins book, and the recently released attack on religion by Stenger that I mentioned in the previous post, is a result of the extreme religious fanaticism imposed into the American political and social scene. I think those who are stuck in the middle have very important choices to make.
Zz.
God: The Failed Hypothesis?
OK, throw another log in the atheism fire.
Early this year, I gave a link to Steven Weinberg article on The Designer Universe - his treatise on why physics has made it acceptable to not believe in the existence of God. Of course, there is also the Richard Dawkins book The God Delusion, that became a runaway bestseller, which not only removed all apologies about being an atheist, but also promote it by pointing out "fallacies" about believing in God.
So now we add another champion to the same cause. Vic Stenger has written a book titled God: The Failed Hypothesis. In it, he claimed to have tested all the claims made by the Judeo-Christian-Islam belief and falsifed them based on science.
It is certainly a provocative claim, and I'm sure, will incite a lot of very lively discussion all over the 'net, if it hasn't already.
Zz.
Early this year, I gave a link to Steven Weinberg article on The Designer Universe - his treatise on why physics has made it acceptable to not believe in the existence of God. Of course, there is also the Richard Dawkins book The God Delusion, that became a runaway bestseller, which not only removed all apologies about being an atheist, but also promote it by pointing out "fallacies" about believing in God.
So now we add another champion to the same cause. Vic Stenger has written a book titled God: The Failed Hypothesis. In it, he claimed to have tested all the claims made by the Judeo-Christian-Islam belief and falsifed them based on science.
It is certainly a provocative claim, and I'm sure, will incite a lot of very lively discussion all over the 'net, if it hasn't already.
Zz.
Monday, February 05, 2007
Thursday Night Football with Tim Gay
Hey, if you are in Denver, CO during the week of March 5, you might want to attend this public lecture, which is a part of the American Physical Society (APS) March Meeting.
Thursday Night Football with Tim Gay
7:00 pm Thursday, March 8, 2007
Adam's Mark Hotel
Grand Ballroom, Tower Building
1550 Court Place, Denver, CO 80202
Zz.
Thursday Night Football with Tim Gay
7:00 pm Thursday, March 8, 2007
Adam's Mark Hotel
Grand Ballroom, Tower Building
1550 Court Place, Denver, CO 80202
Zz.
More Undergraduates Turn To Research
This news article describes the very "fashionable" trend of undergraduate research. It seems that there is an increasing effort for undergraduates to go beyond just classroom work and involve themselves with research projects.
I've certainly encouraged physics students to do this if they can afford it. And by "afford it", I mean as in being able to afford the time and effort. It certainly does not make any sense if the student is already struggling with school work and tries to add even more burden by doing an undergraduate research project. So it is certainly recommended for those who can handle the extra work.
Zz.
I've certainly encouraged physics students to do this if they can afford it. And by "afford it", I mean as in being able to afford the time and effort. It certainly does not make any sense if the student is already struggling with school work and tries to add even more burden by doing an undergraduate research project. So it is certainly recommended for those who can handle the extra work.
Zz.
Sunday, February 04, 2007
Phil Anderson to Receive Honors for "Go"
Phil Anderson isn't new to receiving awards, nor does he needs another one. Still, this is rather unique, I would think. I did not realize that he is an avid Go player. It appears that he has been one ever since he did his stint in Japan, and has been promoting it ever since.
Due to that, he is to receive an award from Nihon Ki-in, the association of Japanese professional Go players and teachers. Apparently, this has only been awarded 3 other times in the US, including one to Albert Einstein, who, coincidentally, was also at Princeton.
Just another facet of Anderson's life that I never knew before.
Zz.
Due to that, he is to receive an award from Nihon Ki-in, the association of Japanese professional Go players and teachers. Apparently, this has only been awarded 3 other times in the US, including one to Albert Einstein, who, coincidentally, was also at Princeton.
Just another facet of Anderson's life that I never knew before.
Zz.
Saturday, February 03, 2007
Nanocantilever
This is such a clever invention.
A group at Caltech has made what is essentially a nanocantilever that can "weigh" masses down to the attogram scale, but without the need for cryogenic temperatures and ultra high vacuum. This is quite impressive.
Zz.
A group at Caltech has made what is essentially a nanocantilever that can "weigh" masses down to the attogram scale, but without the need for cryogenic temperatures and ultra high vacuum. This is quite impressive.
Zz.
Friday, February 02, 2007
The Moon Can Be Shocking
You could get all charged up by going to the moon, literally!
A group of scientists have estimated that the surface of the moon can have a high build up of charges. Such build up can be as high as 4500 volts! This could be detrimental to metals and other electrical equipment.
Shocking, isn't it?
:)
Zz.
A group of scientists have estimated that the surface of the moon can have a high build up of charges. Such build up can be as high as 4500 volts! This could be detrimental to metals and other electrical equipment.
Shocking, isn't it?
:)
Zz.
US Science Funding in FY2007 Budget
Here is a bit more on the recent debacle of US science funding. This is a well-done article on the catastrophe that was just recently averted. It describes how we arrived at the mess, what could have happened had the mess continued, and how we had barely survived it.
Science, and especially basic physics research, is still not out of the wood. Funding for fields such as astronomy and high energy physics is still very dire. The Tevatron at Fermilab WILL still end its operations by the end of 2009, ending ALL major high energy physics collider experiments on US soil for the first time in the history of high energy physics.
So there are still more work to be done here.
Zz.
Science, and especially basic physics research, is still not out of the wood. Funding for fields such as astronomy and high energy physics is still very dire. The Tevatron at Fermilab WILL still end its operations by the end of 2009, ending ALL major high energy physics collider experiments on US soil for the first time in the history of high energy physics.
So there are still more work to be done here.
Zz.
ISU Provost Recommends Closure of Physics Program
I reported earlier about the closure of the Physics department at Reading University in Great Britain, and the problems with the physics program in UK universities in general. If people think this problem is exclusive to the UK, think again. It is also happening in the US, but maybe not with the same trend. The physics program at Indiana State University is on the chopping block, along with other degree programs.
I suppose this is always an issue at schools with very small programs. It has to be decided between the need to have such a program that serves the university community as a whole versus the cost of continuing a program that has a small number of students and graduates each year.
Ironically, while ISU is facing closure due to low enrollments, another university in the same state is having stellar number of enrollments. I reported earlier that Indiana University is reporting a significant increase in the number of physics majors, a trend that is in line with the statistics reported by the AIP.
With the number of physics students in high school reaching record levels, it would be interesting to see if that has an effect on enrollments at smaller programs such as the one at ISU. Not sure, though, if that would be in time to save the ISU physics program.
Zz.
I suppose this is always an issue at schools with very small programs. It has to be decided between the need to have such a program that serves the university community as a whole versus the cost of continuing a program that has a small number of students and graduates each year.
Ironically, while ISU is facing closure due to low enrollments, another university in the same state is having stellar number of enrollments. I reported earlier that Indiana University is reporting a significant increase in the number of physics majors, a trend that is in line with the statistics reported by the AIP.
With the number of physics students in high school reaching record levels, it would be interesting to see if that has an effect on enrollments at smaller programs such as the one at ISU. Not sure, though, if that would be in time to save the ISU physics program.
Zz.
Thursday, February 01, 2007
Reflections on Physics by C.N. Yang
C.N. Yang did a reflection on physics and his life during his last visit to CERN. As someone who has made several key contribution to the field of elementary particle physics, he certainly had a front-row seat to what has been going on in that field for the past 50 years.
I like what he said at the end of the article.
That would certainly turn physics upside down.
Zz.
I like what he said at the end of the article.
In the meantime, what does he think will be the most important discovery at the LHC? "Everybody is focusing on the Higgs and most feel it will be discovered," he observes. "But," he adds, "it may be more exciting eventually if it is not discovered."
That would certainly turn physics upside down.
Zz.
Physics Shows
This is a rather interesting report. Undergraduate students at University of Bonn developed a 2-hour physics show for the general public that would be understandable to kids aged 10 and up. It appears that the exercise is effective in getting the students to understand the physics concepts even more. Not only that, local high school students have also picked up on the idea and started putting up their own shows.
When I was an undergraduate at U. of Wisconsin-Madison, I had the opportunity to attend a yearly physics show by Dr. Clint Sprott called The Wonders of Physics. It was very popular, and the lecture room was always packed. It has now grown to be very popular and I think he even do some road shows.
Zz.
When I was an undergraduate at U. of Wisconsin-Madison, I had the opportunity to attend a yearly physics show by Dr. Clint Sprott called The Wonders of Physics. It was very popular, and the lecture room was always packed. It has now grown to be very popular and I think he even do some road shows.
Zz.
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