Do Cosmic Rays Get Bogged Down in the Cosmos?

A new report out of the Auger Observatory collaboration seems to indicate the presence of the GZK cutoff (link requires free registration to Physics World website) that was earlier claimed by the the HiRes observatory.

Physicists are closer to understanding how ultrahigh-energy cosmic rays make their way to Earth thanks to new measurements made at the Pierre Auger Observatory in Argentina. The study shows that the number of such cosmic rays reaching Earth drops off rapidly for rays with energies of more than about 4 x 10^19 eV.

The observations are consistent with a 40-year-old theory that ultrahigh-energy cosmic rays cannot travel very far through the universe without losing energy as they scatter off the cosmic microwave background.

4 x 10^19 eV... hum.. quick! How many orders of magnitude is that higher than the highest energy the LHC can ever reach?! And people are rabidly worried about the LHC creating blackholes?

Zz.

Earth Will Survive After All

This came out last Friday, but I've only finished reading the whole thing just now. As reported in The NY Times today, all the concerned regarding the safety of our Earth due to the LHC has no significant probability of happening. This is based on the report that was released a few days ago.

And note the argument that I've used all along from the Auger Observatory results.

Do I think this will silenced all those doomsday-sayers? Nope, because most of them have already made up their minds with their so-called "facts". They'll still be singing the same tune even 10 years after LHC has gone into operation, because people never learn. A few of the people that I know will probably be at there when the LHC begins not only the first particle beam this July, but also the first collision, which from what I've been told, probably will begin in Sept. I told everyone to take some pictures, especially if a black hole starts appearing. I want to be the first to post a picture of a black hole swallowing up a part of Earth!

:)

Zz.

EDIT: The preprint by Giddings and Mangano has now appeared on ArXiv.

http://arxiv.org/abs/0806.3381

The abstract is VERY clear:

Abstract: We analyze macroscopic effects of TeV-scale black holes, such as could possibly be produced at the LHC, in what is regarded as an extremely hypothetical scenario in which they are stable and, if trapped inside Earth, begin to accrete matter. We examine a wide variety of TeV-scale gravity scenarios, basing the resulting accretion models on first-principles, basic, and well-tested physical laws. These scenarios fall into two classes, depending on whether accretion could have any macroscopic effect on the Earth at times shorter than the Sun's natural lifetime. We argue that cases with such effect at shorter times than the solar lifetime are ruled out, since in these scenarios black holes produced by cosmic rays impinging on much denser white dwarfs and neutron stars would then catalyze their decay on timescales incompatible with their known lifetimes. We also comment on relevant lifetimes for astronomical objects that capture primordial black holes. In short, this study finds no basis for concerns that TeV-scale black holes from the LHC could pose a risk to Earth on time scales shorter than the Earth's natural lifetime. Indeed, conservative arguments based on detailed calculations and the best-available scientific knowledge, including solid astronomical data, conclude, from multiple perspectives, that there is no risk of any significance whatsoever from such black holes.

Any challenges MUST be done with physics, using at least the same level of meticulous study, and not by a series of quotations attributed via 2nd hand information from other people.

Peter Higgs on the Dawn of the LHC

I mentioned earlier of an article referring to Peter Higgs and the impetus for him to come up the Higgs mechanism. One doesn't hear much about Higgs since he's a very low-key individual. So it is rather nice to read about him and what he's up to nowadays, especially on his recent visit to CERN. This news article is basically an update on him especially with regards to the LHC about to be powered up.

Zz.

Particle Physics Project Prioritization Panel

It was reported earlier that the particle physics in the US is getting some "lifeline", based on the initial report to be submitted to the Dept. of Energy. The panel, known as P5, has now submitted its final report to the DOE.

Various reports on this seems to indicate a reason for optimism, even when the panel gave a lukewarm support for the ILC. Unless there's some serious infusion of cash, I can't see how anyone can be optimistic about the situation, especially when another continuing resolution is almost a certainty for the 2008 Fiscal Year, where science in the US will be saddled with continuing the most devastating budget in recent memory.

Zz.

US Particle Physics Spared the Axe?

Well, maybe for now.

The High Energy Physics Advisory Panel (HEPAP) that advises the Dept. of Energy, met this past week to make recommendations on future directions of high energy physics funding and projects in the US. This New Scientist article seems to be painting a "rosier" picture than it really is.

You can read the preliminary report of the P5 meeting here.

There's nothing here that indicates that the politicians (and the President, now and the one to be installed in 2009) pays any attention to such report. After all, they've been known to ignore previous recommendations.

And as a follow-up to the post from yesterday regarding the anonymous donor that gave $5 to help Fermilab, Wired has this dead-on article about the sad state of American particle physics funding.

Say what you will about the relative importance of particle physics in everyday life, but how is it that a government spending $16.8 $2.9 trillion a year can't scrounge up enough change in the cushions to properly fund its premiere particle physics lab?

In the scheme of this country, we're not talking huge amounts of money here. The Federal government's total budget for the lab is $320 million. That's as much as we spend on, say, two-and-a-half F-22 Raptors, and we've managed to build over a hundred of those. Even just the interest on our nation's collective credit card was more than 1,000 times the Fermilab's budget.

... which is essentially what I had said earlier. People have somehow lost perspective for the scale of things.

Zz.

Behind a Scientific Success, a Failed Texas Experiment

As the dawn of the LHC is upon us and the excitement growing by the day, a relic of what could have been the most powerful particle collider ever built sat decaying and gathering dusts in Texas. This article looks back at the debacle that was the Superconducting Supercollider what was supposed to be built just outside of Dallas.

The Tevatron ring measures about 4 miles in circumference. The SSC ring was to have been 54 miles in circumference, producing collisions 20 times more intense than the Tevatron.

The new European accelerator, called the Large Hadron Collider, will not be as powerful as the mighty SSC would have been. The Large Hadron Collider's ring, about 17 miles in circumference, should be capable of producing collisions about one-third as powerful.

The collapse of the SSC is also an example on how politics got into the way of a science project, especially in how Fermilab lost the opportunity to build it there. It also shows very clearly for the first time that physicists are not united behind such huge and horribly expensive machine. Phil Anderson, for example, testified on why he was opposed to such a facility.

The SSC would have made the LHC moot. However, the SSC collapse has also foreign partnerships with the US more weary about the US commitment to such endeavor. The recent budget cutbacks on the ILC and ITER only reinforced such point of view.

Zz.

Arsenic Poison Didn't Kill Napoleon

Another myth bites the dust.

A new study by physicists at INFN in Milano-Bicocca and Pavia, Italy, has shown that there's no difference in the arsenic level in Napoleon's hair during his last days when compared to when he was a child. This means that he wasn't deliberately poisoned by arsenic during his last days. Instead, it was more likely that it was due to a lifetime's worth of exposure to arsenic.

Zz.

Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks

I just want to say that I had a lot of fun reading this preprint by Joseph Kapusta. It is entertaining, insightful, and has a ton of information for both scientists and non-scientists alike. It reinforces the point that I've been trying to make, which is the constant miscommunication between scientists and non-scientists. The blame goes on both sides - scientists for not considering how what they say is being interpreted by the public, and the public for not self-educating themselves into trying to understand not just the science, but the vocabulary that science uses. Not being aware that there are discontinuity in the communications and understanding of the two parties is the first significant problem. This is also a very good opportunity to again highlights the wonderful essay written by Helen Quinn that I've mentioned a while back. Everyone should read it!

If you have some time, I'd recommend reading this article by Kapusta, even for just for its "storytelling" aspect.

Zz.

A Case Study of Gender Bias

OK, this thing has the potential of becoming a rather big news especially when the popular media picks it up or the a coverage in Nature (whichever comes first). This arXiv preprint titled "A Case Study of Gender Bias at the Postdoctoral Level in Physics, and its Resulting Impact on the Academic Career Advancement of Females" is getting quite a bit of legs. You might want to also look at the trackback links to read more about it.

I'm not endorsing or disputing the report, simply pointing it out since the cat, obviously, is out of the bag. I'm guessing there's more to come on this.

Zz.

April 14, 1932 : The Era of Accelerator-Based Particle Physics is Born

A good piece of history in this article on the historic occasion that happened today in 1932.

Zz.

Thousands Showed Up for CERN's Open House

Fifty thousand, to be exact. It was the last time the public will get to see many parts of the facility before they are closed down for the expected start-up in July. I suppose all the brouhaha about CERN and the black hole creation created even more publicity and even more interest in it.

And now, ladies and gentlemen, start your engine!

Zz.

Follow-Up To The LHC Lawsuit

I was reading Bob Park's entry (April 4, 2008) of this LHC lawsuit yesterday, and it brought back memories of the almost-identical issue being faced when RHIC was about to start up. It was such a brouhaha that even Comedy Central covered it! :)

It is worthwhile to note of the in-depth study that was done at that time to dispel the myth that RHIC would create not only black holes in its collisions, but a catastrophic one. And unlike the joker who filed that lawsuit, this scenario was brought up not by an ignorant individual, but rather by a few physicists themselves. So certainly it warranted a careful consideration.

However, there were two different issues involved here. The first was the careful study of the claims made within the scenario, i.e. can there be a catastrophic creation of blackholes that could spell disaster. This was easily dispelled because of the existence of the moon (you'll have to read the full report). The second one was more difficult to explain to the general public. In many instances in physics, we see different phenomena that share the same mathematical description or formulation. The similarities of the mathematics from some aspect of condensed matter physics and elementary particle physics is one example. This is again what happened in a RHIC blackhole scenario. The problem here is that once that comparison got out, it caught fire among the media and the general public, who weren't able to know the significance of such a comparison. All they see is the "headlines" of blackholes being created, and that's that.

Again, this is where, if one doesn't have the necessary knowledge to decipher the information, one can be easily mislead by news reports. Sometime, it is the fault of scientists themselves for sensationalizing the issue (example: quantum teleportation, and anything Michio Kaku has written in his latest pop-science book). The public does not have the understanding and the formalism in mind when they read these things, unlike physicists. All they can do is associate what they read with what they know, and what they know come mostly from the media, TV, movies, etc. So it should not be a surprise that they can't tell the different between the "quantum teleportation" as a demonstration of quantum entanglement, and the teleportation they saw in Star Trek. When you use the same word, you should expect the pedestrian meaning of it to dominate, where it is accurate or not.

Zz.

Addendum: Looks like the Editorial in the NY Times has it right.

More than once over the years we have felt as if we were transported to another universe listening to lawyers and judges wield the complexities and arcana of their trade. It would be fun to watch them struggle with theoretical physics. But if the courts have any sense, they will drop this suit into the nearest black hole.

More CP Violation

On the heels of the KEK report that I mentioned earlier, here comes the analysis of the data from the Tevatron at Fermilab that point to the same conclusion.

The amount of CP violation observed in experiments (and enshrined in the standard model), however, is far too little to explain why matter should have prevailed in its ancient war with antimatter. To get a clean look at CP symmetry, DZero and its sibling detector, CDF, focus on the BS, which consists of a bottom quark and a strange antiquark. (Quarks are components of protons and neutrons.) Working independently, the two detectors both found an extra dose of CP violation beyond what the standard model predicts.

Neither result on its own was very convincing, so a team of Italian researchers combined the data, similar to the way medical researchers cull information from independent clinical trials, to look for rare side effects. Together, the data make it 99.7 percent likely that the discrepancy is real, not due to chance, says physicist Luca Silvestrini of the National Institute for Nuclear Physics in Rome, who took part in the study submitted to Physical Review Letters.

Looks like both the CDF and D0 got similar things, which is always good.

Zz.

What is the Matter with the Uuniverse?

More CP violation results out of KEK on the B meson.

To find out the team created pairs of matter and antimatter particles, called B mesons and anti B mesons, and measured how they behaved. The study has come up with a better estimate of earlier measurements that suggest that there is a difference in the rate of decay (they decay into a kaon and pion).

"We have measured two differences of decay rates between b and anti-b," says Prof Hou. " It is around 9 per cent for neutral B and anti-B, and 7 per cent for charged B and anti-B. The bigger mystery, and gist of our paper, is posing the question of why there is this difference."

But the end of the article mentioned about waiting for more results out of BaBar at SLAC. I thought SLAC is no longer doing any particle collider experiment and is already being converted into the LCLS? Did something changed? Or are still going to do limited collider experiment in between LCLS runs?

Zz.

Addendum: I just finished reading the paper in Nature (Lin et al, Nature v.452, p.332 (2008)) and the Perspective on this work by Michael Peskin in the same issue of Nature. The BaBar result they are expecting is the analysis of the large, existing data that have already been collected. So it isn't from any future BaBar experiment. That clears things up a bit, at least for me.

More Addendum: See a report on this in PhysicsWorld.

Review: The Mystery of the Missing Antimatter

This is a book review of Helen R. Quinn and Yossi Nir's "The Mystery of the Missing Antimatter". As the reviewer has noted, there are only 3 major mysteries in cosmology today: the nature of Dark Energy, the nature of Dark Matter, and why matter dominates antimatter in our universe today.

This might be something I might try to get in the next few months. Helen Quinn, if you've read this blog for any considerable period of time, wrote a while back an article that I had characterized as something all scientists and science students must read. So she certainly has a clarity of thought and a concise use of words.

Zz.

Profile of Harry Lipkin

This is an interesting profile of theorist Harry Lipkin. While many of his colleagues certainly know him due to his body of work, many others certainly know of him due to his highly provocative essay in Physics Today several years ago titled "Who Ordered Theorists?" In it, he argued that many of the discoveries and amazing advances in elementary particle physics (and possibly physics in general) have not be due to theorists, and in fact, might have been hindered by them.

Of course, being an experimentalist, I'm not going to argue with that. Still, it brought out a lot of "heated" discussion and rebuttals after the letter was published. Still, I can say with definite certainty that many of the emergent phenomena in condensed matter, for example, such as superconductivity and fractional quantum hall effect, were never predicted by theory. The experimental discovery of the phenomena inevitably always came first.

Zz.

Layoffs At Cornell

I've mentioned of the effects of the disastrous Omnibus budget that was passed recently, and have highlighted how it has severely affected operations and staff at several US Nat'l Labs. But the casualty isn't just restricted to these places. Cornell University has had to lay off about 10% of its workforce at its Laboratory of Elementary-Particle Physics.

The 11 job cuts represent 10 percent of the lab's 110 employees. The laboratory, which studies the laws that govern atoms and molecules, has lost 30 percent of its funding in the last 2 1/2 years, said lab director Maury Tigner.

“The support of physical science throughout the United States has been falling victim to the latest congressional action in which the American competitiveness has not been supported,” he said.

So not only is there a real impact beyond just the high energy/nuclear physics programs, there are also impacts beyond just the Nat'l Labs. I wouldn't be surprised that there are more of these stories around in the months to come, because I don't see the president's FY09 budget proposal being passed, certainly not this year.

Zz.

The LHC As A Time Machine?

Report on this has been circulating the news wire for a few days ever since the silly editors at New Scientists proclaimed that it can happen (shall I mention for the gazillion'th time why I consider New Scientist as the science's supermarket tabloid?). I suppose when colliders like RHIC didn't actually produce blackholes, some people need to come up with other more creative ways to get them free publicity. So why not a wormhole?

We finally have a sensible article that discusses this. Still, the crackpots of the world are already rejoicing and jumping all over this.

Zz.

UK Confirms Withdrawal From ILC

The funding council for the UK has refused to reconsider the withdrawal from the International Linear Collider (ILC) consortium (link requires free registration for full access).

But despite strong protests from physicists, the STFC says in a statement released today that it has “reaffirmed its decision to stop funding the ILC”, which is seen as the next big experiment in particle physics after the Large Hadron Collider at CERN. The statement was released following a meeting of the STFC’s council last week.

Of course, this doesn't sit well with many people.

Brian Foster from Oxford University in the UK, who is European director of the ILC’s global design effort, says he regrets — but is not surprised by — the STFC council’s decision to withdraw from the ILC.

“At no time has council or any of its subsidiary bodies, or the chief executive, seen fit to discuss this ill-informed decision with me or our international partners, but has instead presented it as a fait accompli,” Foster told physicsworld.com. “While I am grateful that various STFC officials are working constructively with me to try to rescue some of the world-leading work in the UK, I can never accept the legitimacy of the deeply flawed process that has led to the STFC’s withdrawal from the ILC. I will continue to make the case for this vital world project in the hope that STFC will rejoin in the future.”

There's a prevailing "doom" around many places that were involved in the ILC. It is quite conceivable that the ILC is dead, and that even with some restored funding, the momentum for it is lost forever, at least for the US and UK. The possible hope for the resurrection of the ILC would be to site it in either Japan or China. It certainly would signify the complete and final end to particle collider experiment in the US.

Zz.

Jefferson Lab Imager Can Detect Beginnings Of Breast Tumors

This is just another clear example where the advances in the techniques used in physics produce a direct benefit in other areas, such as medical imaging. In this case, knowledge of detector physics can produce an early detection of breast cancer tumor that a mammogram could have missed.

The pre-clinical results will be published in the journal Physics in Medicine and Biology on Feb. 7.

"We are physicists," Majewski said. "The medical people decide when this device is ready."

The work of Majewski's team has already been developed for the market by Newport News-based Dilon Technologies. This new research builds on Dilon's model and expands its capability because it has been designed to guide a biopsy, Majewski said.

This is also another example of the practical application of physics, in case you encounter people who think that there's nothing directly beneficial from physics.

It is imperative to point out why investment in basic research is so important. It isn't just for the knowledge, but also the "side effects". Many advances in the medical field and computing would not have occurred if it weren't for work done in nuclear and high energy physics. So when people pour money into the biological and health fields but sacrificing funding in basic physics, they are ignoring this fundamental fact that many of the advances made in the medical/biological fields came about thanks to the fruits of the labor done in basic physics. The public, and especially our politicians, need to be fully aware of that! Whoever is responsible for this story should point out clearly where the technology came from.

Zz.