jump to navigation

Follow up on the CERN Black Hole Flap June 25, 2008

Posted by gordonwatts in Pop Culture, press, science.
9 comments

I’ve not said much (or here) about the lawsuit that seeks to halt the turn-on of the LHC because it may produce a mini-blackhole or other object that devours our earth and the universe. In response to the press when the original suit was filed, CERN sponsored a safety review, which was recently released.

Ars has a great summary of the report:

The report’s conclusion is that, if the LHC were capable of destroying the earth, nature would have beaten us to the punch.

Read the report. It takes 96 pages to arrive at that pithy sentence. 🙂 Or read the Ars bit which is a good summary. They end with:

Overall, it’s hard to read this report and not wind up viewing the apocalyptic fears as simply being poorly thought through. It was striking how clearly the worries over the LHC have parallels to the fears over biotechnology, which came up during our recent interview with Carl Zimmer. There too, billions of years of natural experiments and decades’ worth of scientific experiment should be informing our view of safety; for at least some segment of the public, that’s not happening.

Advertisements

Bust Open That Black Hole! April 3, 2008

Posted by gordonwatts in physics life, politics, press, science.
10 comments

I really didn’t want to say something about this article. Actually, at first I wondered if it was just an excuse to show a truly awesome picture I wasn’t going to write anything. But then it started showing up on tech blogs, it rose to near the top of the New York Time’s most emailed articles. And non-physics friends of mine started asking what I thought about it. And then I saw some of the comments left on the article at the Herald Tribune’s version of the article (read them – it is worth it). I agree with Peter Woit: “it’s unclear why the story deserves any attention” However, I can hold out only so long.

Here is what I think: this article has the legs for reasons similar to why ID and Creationists are able to push the “evolution is only a theory” so effectively.

If you don’t have time to read the article: Wagner (ex physics researcher, lives in Hawaii) and Sancho (author, researcher on time theory (!?), lives somewhere in Spain) are suing Fermilab, the Department of Energy, and CERN to prevent the LHC from being turned on. Their’s is a doomsday worry: a small black hole or something similar will be created in the center of one of the detectors and will quickly expand to eat up the whole universe. Including us. I actually think that I’ve seen Wagner. One day, when I was a graduate student at Fermilab, I remember seeing a collection of people protesting outside the Batavia gate. I didn’t stop, but some friends did. It was someone from Hawaii who was worried we were going to end the universe. I don’t remember the name, but I suspect it was Wagner.

Now, in the evolution and creationism debate we scientist types call evolution a theory. In science it doesn’t get much more iron clad than that – pretty much the top of the heap. Note that we very carefully do not call it a fact. The reason is that science is always looking to improve the answers. We may have a model that fits all of our observations – but that isn’t to say that we’ve not missed something thus will need to extend the model or theory at a later time to account for new observations. Scientists are very careful about declaring the limits of their knowledge, and are very reluctant to go out on a limb and make a statement for which they do not have supporting evidence. That is part of the reason why we don’t call evolution a fact.

Now, lets go back to the article. There are lots of papers talking about mini-black holes and their possible production at the LHC. So far no one has seen any evidence of a black hole generated at any of the operating accelerators. But can you get any scientist to declare: “Absolutely, under no circumstances, ever will there be a black hold like this produced.”? I doubt it. If you asked a particle physicsts if they were worried about it – I don’t know of any that would be. Most would love to be at CERN, in fact, when the LHC starts up. I’d love to be there, but I may be teaching instead.

There is another aspect in this – risk evaluation. For example, it is much more dangerous to drive in your car than fly in an airplane. That is the raw science (statistics, whatever) of it. Yet we fear flying. When it comes to something like this how do you evaluate the risk? There is no way a non-scientist can do it themselves. The more science literacy there is the better people will understand the language that scientists use, but… And there is no way you would want to limit scientific endeavors and research to the list of topics that the non-scientist can easily understand! Ahhh… outreach!

Obligatory joke: fear not; us particle physicists will be first to pay if we’re wrong. 😉

But you have to admit — that is one amazing picture of CMS! These large detectors are stunning. I think someone should gather up the copyrights for some of these pictures and make a lulu.com book or something like that.

The LHC did make BlackHoles October 7, 2008

Posted by gordonwatts in LHC, life.
1 comment so far

This joke was told to me by the father of a friend at a 1-year-old birthday party. He isn’t a scientist, but, like many people, fascinated by the science that is going on.

I see the LHC did produce a blackhole after all! It just drifted over to wall street and is starting to swallow the universe there…

I’m sure we can rewrite this to make it better – but the idea is just too good to not write it down…

Better in Essay Form April 15, 2008

Posted by gordonwatts in LHC, press, science.
add a comment

There is an essay by Dennis Overbye in the NYTimes today that is a much better discussion of the black hole flap that occurred a week ago, generated by a real article by Dennis. My favorite (laugh) quote:

Besides, the random nature of quantum physics means that there is always a minuscule, but nonzero, chance of anything occurring, including that the new collider could spit out man-eating dragons.

And my favorite serious quote:

“As in all explorations of uncharted domains, there may be a risk,” Dr. Rees wrote, “but there is a hidden cost of saying no.”

Definitely worth a read – much more so that the actual article itself, I think.

Particle Physics Is About to be Sexy Again February 11, 2008

Posted by gordonwatts in press, science.
9 comments

Well, that is what the Economist says in a small science and tech article:

Unfortunately for Dr. Aymar, it is Dr. Heuer who will reap the reward, for after a decade and a half in the wilderness since the United States abandoned its own plans for a giant accelerator, called the superconducting super-collider, the subject of particle physics is just about to get sexy again.

Besides the implied total write-off of the Tevatron (grrr!), cool! Glad to see that the Economist gets it. Earlier on in the article it points out why things are about to get sexy again:

Inside it, he and the thousands of other physicists who work at CERN hope to find the secrets of the universe: dark matter, dark energy, extra dimensions, tiny black holes that evaporate in an eye-blink and the origins of mass itself.

This article was written because Dr. Heuer is about to take over from Dr. Aymar as the head of CERN (a big deal, obviously). And the article was pointing out that Aymar has worked hard to make the LHC come in on time and on budget (well, sort of), but will not be director any longer when the machine turns on and starts producing physics. Bad luck, eh?

CHEP Day 1 September 13, 2007

Posted by gordonwatts in computers, physics.
add a comment

I’m spending this week in Victoria, Canada attending the Computers in High Energy Physics (CHEP) conference. At one time this was my favorite conference (more on that in a later post). These summaries are just things in the talk I found interesting. [I spent last week there — I’m just getting around to cleaning up these posts!!!]

The first day was both Plenary and parallel sessions. They are using Indigo which means everything can be seen online. I came in on the Clipper in the morning, so I missed the first two talks.

Plenary: LHC Computing – Ian Fisk

CHEP - Fisk - PuzzleIan talked mostly about HEP’s use of the GRID – that big computing appliance in the sky… err, I mean cloud. He showed a great slide that really tells you how much trouble we’ve gotten ourselves into – all those layers up layers in the GRID: “Not all of them included just for technical reasons.” We keep adding layers and adding layers to hide complexity. It is no wonder some of our systems are so fragile! He points out that everyone is developing their own front-end system interface to the GRID. He made the point (along with others before and I’m sure after)  that the level of complexity means that we have to develop more and better automated testing of the tools.

The ALICE experiment has the ability to make custom datasets based on simple event cuts. A user can define a particular set of event attributes and have a dataset made from that. I can’t help but wonder how that scales if every user requests their own dataset (which is very similar to the next user’s) – that is a lot of I/O. But it is good, none-the-less. I see this in ATLAS too with the TAG – but I’m nervous of the same scalability problems there too.

ALICE also has a clever way of sending jobs out to the GRID (I think this is old hat now): the pull model. They submit a little pilot job. It checks out the machine for basic installation and then calls back to a central scheduler to get the actual job that needs to be run. I’ve known this gives them the ability to avoid black holes, but I didn’t appreciate how much more job scheduling flexibility it gave them: some GRID submission queues can be very long!

In the first reference to multi-core (of many!) he pointed out that with the new machines we are using now we need 8 or 9 copies of the simulation or reconstruction running at once in order to fully utilize the capabilities of a 8 core machine.

In general he painted a rosy picture of the tools. This didn’t match my experience and I asked how things look so good but seem to not work for the end user. He mused that perhaps 90% operation was still pretty bad from an end user point of view. I think it is still worse. I got a bunch of ribbing for that comment later on in the conference. 🙂

Plenary: LHC DAQ – Sylvain Chapeland

This was the usual overview of the LHC DAQ. One thing impressed me was that every one is using ROOT to display plots. Java makes an appearance also, but ROOT is the real king here — any time a plot has to be made. Most of the operational displays shown were a few buttons and lots of histograms — I usually think of DAQ operations being a bunch of buttons and some text files. I think this was speaker bias.

He had a comment on the last slide — wondering if we couldn’t have a common DAQ system. Years ago I also wondered why we couldn’t do that. At the very least, a common DAQ system. Indeed, Fermilab has a project that does this for their fixed target experiments (I can’t remember the name). I think this will never happen for the large experiments like ATLAS or CMS. The hardware is so specialized, and the dataflow is so specialized. I can imagine that we might make use of libraries of utilities — but we’ll never see unification of the overall DAQ system or its control.

Plenary: Computer Facilities – Eng Lim Goh (sgi)

Unfortunately, the slides have not been posted. This talk was fascinating (as were all the vendor talks, actually). Goh noted that the data rate out of the ALICE DAQ system, 1.2 GByte/sec, was the same as what the film industry was seeing for their “4D” compression for a movie – so the real world is catching up!

He has seen 10,000 node rack & stack clusters close to production and hears people now talking about 100,000 node rack&stack clusters. Wow!

sgi’s vision of the future are very tightly packed racks. They do away with the pizza box stacking and instead just build CPU’s on a board, stuff the boards into a special high speed back plane, and build modules out of these. Input and output uses Infiniband, which gives performance on par with 10 Gb ethernet.

Supplying power was also a focus — and doing it efficiently. Apparently, one usually gets from line voltage via two steps. sgi has put it in a single step, and they have brought the power supply out to the back of the rack to supply a whole lot of nodes – thus they claim to have one of the most power efficient (watts/flop). Of course, Goh mentioned the backplane that they plug all their processors into now has 1000 amps coursing through it! Yikes!

Despite the efficiency improvements, they still have to cool the rack down – they use water cooling. Goh claims it is neutral — you don’t have to add extra AC to the room – the water chiller will take out at least as much heat as what goes in. Interestingly enough, the coolers are mounted on the back of the rack, after the air has flowed through the processor.

The solution is quite unique — in that it doesn’t play well with other solutions. This question was asked, and Goh said that in units of a single rack it did play well — sgi supplies standard GB interfaces in and out of a rack so that one’s whole data center doesn’t have to be infiniband.

Parallel: ATLAS Analysis Model – Amir Farbin

I managed to miss most of this (late back from getting a Dr. Pepper!), but his talk mentioned several things that looked interesting that I’m not already familiar with:

  • SPyROOT – The specific example knows about data sets, relative luminosity, and cross sections and can automatically make plots for multiple datasets at once. Written in Python. The batch version seems to be a simplified version of what we use in D0 (in Python rather than C++). Cute. Not obvious it is robust enough – seems designed only for simple things — no way people are going to end up doing just simple things there!
  • We will only simulate 20% of the data we take. I hear this said all the time. A particular analysis only looks at a small subset of the data — will this number matter?

He also talked about his EventView approach to doing analysis — which I think is not going to work out well.

Parallel: A Class To Make Combinations – Nobu Katayama

This was a very cool talk on an algorithm to solve a physics problem – a set of ideas you could walk away from CHEP with an immediately apply. I’d like to see more of this sort of thing!

Nobu was dealing with combinitorics in B-physics. Specifically, a 3 body decay. He wanted to represent it with C++ operator syntax: “D0 = Kaon*Pion*Kaon” — in order to do this you need to loop over all three objects at once, but C++ operator syntax means you will do the Pion*Kaon first, and then the Kaon*<result> second — not evaluate all three. So he wrote a delayed evaluation library: it builds up a syntax tree of all operations but doesn’t actually do them until the “=” sign is hit. At that time the whole parse tree is available and he can see that he needs to do a 3-way combination. Very cool! I’ve seen this technique used to solve all sorts of computational problems (like shipping matrix operations out to a GPU).

I asked why not use a Domain Specific Language: a text file that contains the physics in a more readable form that you could then use a program to automatically turn into C++: easy to read and write, and the speed of C++. He really wanted to complete flexibility of C++ available (for cuts, etc.). Sounds good!

Parallel: The CERN Analysis Facility – J. F. Grosse-Oetringhaus

ALICE is probably the heaviest user of ROOT of any of the ongoing large experiments. They use it for everything – reconstruction, simulation, visualization, etc. You name a feature of ROOT, and they are using it. This includes PROOF, the remote cluster version of ROOT. They currently have about 40 machines setup (500 is the goal). PROOF has, from the sounds of it, received significant debugging on this cluster. 🙂 Listening to this talk you really get the idea that PROOF is big-iron. Lots of support is required to have a fully functioning system, which is too bad.

I asked how you distribute user code and libraries – you send source files and they are compiled on each PROOF machine that is running. What do users do when they want to run an analysis in PROOF with lots of plots – speaker didn’t know, but he did know that some people were making 100’s of plots in a single event loop (the only way to do it, in my opinion).

Parallel: Visualization with ROOT – Matevz TADEL

Wow. ROOT visualization is pretty impressive! The ALICE detector is a heavy-ion detector. This means when the ions collide there will be a huge mess of tracks in their detector. They are using the visualization code in ROOT as their detector display, and they claim decent performance when they show as many as 1000 tracks. And this is without using acceleration hardware (as far as I can tell). I wonder how fast things would go if they used modern graphics cards and did processing there?

Parallel: The Online Track

There were a lot of good talks on High Level Triggers at this point in the Online Track — but I have seen many of them before. Suffice it to say that good progress is being made and people are already at the point of testing the algorithms to make sure there is enough CPU to do the things that they need. In particular, one referred to a version of the track finding algorithm, called a Kalman Filter, that didn’t require matrix inversion (very slow). I’d not heard of this gain-matrix formalism before, but I found what looks to be a decent reference on the web.

You young people going to let… October 10, 2006

Posted by gordonwatts in computers.
1 comment so far

This came a cross the large mailing list we use here at DZERO to discuss our 1000 machine compute cluster. It was having some problems: one bad node was swallowing all the jobs (aka a black hole). A reply was sent with links to monitor tools so the folks complaining could figure out what was going wrong. The universal response from other users was “uh, I have no idea what this means.” To which the original poster wrote back, a little frustrated:

And by the way, I’m not a Fermilab employee, I’m not even just a professor, I’m a Dean. You young people going to let a frigging Dean know more about your computing systems than you do?

Ha!

2009. Ready or not January 2, 2009

Posted by gordonwatts in ATLAS, CERN, D0, Fermilab, LHC, politics, science.
4 comments

We’ve made it through the first day of 2009. I have mixed feelings about this coming year.

  • Federal Science Funding Levels. The economy is crashing down around our ears. Business responds quickly (layoffs :() – government is a bit slower. If things followed their natural course of action that would mean science funding, along with everything else, will take yet another hit. However, the incoming Obama administration seems to be committed to spending the USA’s way out of this recession, so in the end funding might not change very much. I am hopeful that hard sciences funding will remain at least stable.
  • Federal Science Funding Directions. Climate change is what the Obama administration is focused on. There is a good chance that if you are researching something connected with climate change you may have access to increased funding opportunities. I would expect a funding profile similar to NIH’s funding during its years of increase. I would like to think that funding will spill over into the physical sciences – it should because there are connections between the physical sciences and clean air technologies. All of this is applied scientific research. I hope that the pure research funding gets an increase as well, as an investment in this countries future (particle physics is pure research, of course). I’m feeling neutral here.
  • Federal Science. Obama’s science team is just a BLAST of fresh air when compared to the current administration’s. After all, his DOE nominee is a Nobel prize winning experimental physicist. Even if the science advisor isn’t elevated to a cabinet position (PDF), there will be someone in the room that knows a great deal about science, research, and how it is done. Even if there are cuts to science funding, I’m very hopeful there will be intelligent cuts rather that unscientifically motivated cuts. I’m very hopeful in this respect.
  • State Universities. The economy in states is depressing. Some states, like my own (Washington) that rely on sales tax are being hit hard and very fast. State universities can’t escape that, obviously, and my university is no exception. Unfortunately, this usually translates to reduced raises, inability to counter offers from outside, reduced support for research, etc. In our own department I wouldn’t be surprised if some people left for other universities that, for whatever reason, were able to make good offers in this awful climate. There is, in fact, already evidence this is happening. The only consolation is most universities are in the same boat, and so most of them are having similar problems. I know less about private universities, but I do know the endowments of many of them are also having difficulty. I’m very downbeat about this: it will be a rough two years at least, I think.
  • My Science. When it comes to the Tevatron and the LHC… Well, I see no reason that the Tevatron shouldn’t continue to break records in luminosity (they just broke one earlier this week). And the experiments will continue to be flooded with data. While it is possible for one experiment or the other to have a catastrophic failure, I doubt that will happen. And they should continue to produce papers and science at a furious rate. I also am looking forward to real LHC collision data this year. While I hope it will be at the full 14 TeV, I suspect it is more likely to be at 2 TeV, just a hair above the Tevatron’s luminosity. We’ll hopefully know what the machine scientists think about that sometime in February. I’m really hopeful about this.
  • New Years Resolutions. Well, I made only one. That way I have a hope of keeping it: make bread more often. 🙂 I think there is a chance that I will keep this one. Especially now that I’ve said it publically. 🙂

Of course, this should also be a fun year, as noted by the Beacon News:

Frustrated with their failed attempt to destroy the world in 2008, the scientists at Fermilab and their counterparts at Switzerland’s CERN physics lab resolve to perfect their new device, the Large Planet-Sucking Black-Hole-o-Tron.

Here is to another great year of data collection and science at the Tevatron and first collision data at the LHC!

This is getting to me… October 13, 2008

Posted by gordonwatts in politics.
add a comment

IMG_7807Palin is everywhere! I was at a small birthday party last week and I saw this on one of the tables. A Korean magazine. Everytime I see her it makes me recal how my thinking of her and the McCain ticket have evolved:

  • Pre-Palin – seems like he would be ok, don’t know that I would vote for him because some of his positions are not mine, but he would be better than bush.
  • Palin-Pick – Who is this? From Alaska? Has he pulled a fast one and changed the whole race?
  • Near-post-Palin – Ok, this has got to be a joke. She doesn’t sound like she has the experience at all! McCain seems to have not only been a maverick here, but also irresponsible. I think the election is over!
  • Convention – Holy cow, really? She gives McCain a bump? How does that work! Do people really like the idea of her being president or is it something else!? And McCain/Palin are now drawing even with Obama/Biden!?? Boy, was I ever wrong.
  • Post-Convention – The more I hear about her the lower my opinion of her as a VP candidate sinks. It seems totally irresponsible and a rather cynical pick by McCain. As a result, my opinion of McCain has sunk even further.

The other thing that really gets me is the republican’s don’t seem to be willing to do the hard work. Running the USA is no small job! The person that is going to do that has to do lots and lots of homework – pretty much training for it for years. And they still won’t be ready (there is always on-the-job training for this in my opinion)!! The republicans seem to be taking the attitude that if they yell loud enough that we will all be cowed into thinking she will be ready. A play from an old playbook, I suppose. I am hopeful that it isn’t working. Even Brooks has called her a cancer on the republican party!

When it comes to trade I tend to lean more towards traditional republican positions (i.e. I do think free trade is a good thing). For business I’m probably between the two parties somewhere. I’m certainly more democrat than republican when it comes to how government should interact with society, and I’m definitely democrat when it comes to social values (vs the modern republican party).

I am hopeful (fingers crossed!) that the republicans will get the butts nailed in this election and realize they have to go back to the drawing board and put together serious candidates at the national level. It would be horrible to me if the current horrid behavior was rewarded.

I’m in the Market for a New Digital Camera November 27, 2007

Posted by gordonwatts in Marseille.
12 comments

My old one, a Casio 8 megapixel, was in fine shape. But what good is a camera that has been stolen???

Yes, I’ve had my Marseille moment. I have no idea how the twerps did it, but they got through a solid steel door (more than a 1/2 in thick) with steel pins in the door frame designed to prevent exactly the kind of forced entry the fellow used. Totally busted the lock.

We live on the 5th floor. They did this sometime during the day, so they had full run on the place. And they took their time. Looked at almost everything here. All the cubards were opened, papers rifled through. What did they take? My nice Sony HD3 camcorder, my casio, $100 bucks, and a few others small things. I guess they were just looking for things that would fit in their pocket.

At the moment this is mostly a real pain. While I’m angry about loosing the Sony I still really like it (it was $700 when I originally got it). The Casio I’ve been unhappy with for a while. $100 US dollars? At the current exchange rate what is that? About 10 euros or something!? But the pain is the locksmith. Staying home several days in a row, etc.

The police were something else. They came over the same night to fill in a report. Then the next day, today, another group dropped by and finger printed my whole place. There was fine black dust everywhere. Mostly you can wipe this stuff up with a dry cloth. But not off any Apple Computer box. Whatever those white boxes are made of hold onto that soot very tightly. I knew there was a flaw in Apple’s products!!

But he left lots of stuff. A few small pocket drives (worth about 100 euros each), a computer (which wouldn’t have fit in the pocket) and some other stuff. Very odd.

At any rate. It has been nice staying home. I got out to a nice place for lunch instead of the Luminy cafeteria.

Oh, and my flickr account is going to be quiet until I replace that camera — which may be Christmas time!