- My ficus died. Please send condolence cards directly to the Composting Council of Canada.
- Wired has an article about the LHC: Subatomic Inferno Under the Alps
- The December Issue of Phyiscs Today has reviews of Peter Woit's and Lee Smolin's books. The reviews aren't exactly nice, but kind of interesting and different from other reviews I've read so far. The author, Kannan Jagannathan, roughly says all this talk about the so-called-crisis is on weak feet, and The End of Physics is nowhere near by. He ends with the sentence 'Smolin and Woit appear to think that it is time to cut the short-term benefit of the doubt for string theory, but many other physicists might be willing to let a little more time pass before rendering judgement.' I agree on most of the criticisms Jagannathan raises, but I think that he's shaking off the raised concerns in both books too easily.
- If you still have doubts that Waterloo, Ontario is the place-to-be, let me mention that the construction area on King Street has eventually turned into the Waterloo Town Square. This doesn't only mean that PI has now a Starbucks withing 3 minutes walk (or a 10 minutes drive respectively, because you don't get out of the parking lot), but also the largest LCBO in Southwestern Ontario (that LCBO being the place where you're supposed to buy liquor).
"TORONTO, Oct. 24 /CNW/ - With popping corks and toasts with Ontario sparkling wine, the LCBO today officially opened its new Waterloo Town Square store at 115 King Street North in Waterloo. The new 16,633 square foot store is the largest LCBO outlet in Southwestern Ontario [...]" >>read more
For some photos, see here. - The German magazine 'Der Spiegel' has an article titled 'Weltall aus Musik' (Universe made of music). Which briefly mentions Lee Smolin's and Peter Woit's books, but mostly makes fun out of the string theory landscape. That fun being on an elementary school level of the form:
"In a faraway Cosmos, there live intelligent Dampfnudeln [a bakery]. They can travel almost as fast as light. For this they use the recoil of improved pressure cookers. [...]"
The article cites Wolfgang Lerche saying "A deep gap is dividing particle physics. String theory is forced onto the defensive.". Besides this, the article hardly contains any interesting information. - Last week, V. Mukhanov gave a very nice colloquium about inflation which is now online:
Inflation after WMAP (Windows Media , Macromedia Flash , MP3 Audio , PDF)
Speaker(s): V Mukhanov
Date: 23/11/2006 - 11:00 am
If you are looking for an easy to follow introduction, I can recommend the talk. It is also quite entertaining. - If you want to see a cosmologist getting upset about inflation, look at this video.
- Yesterday I stumbled across this interesting paper:
Quantitative Analysis of the Publishing Landscape in High-Energy Physics
Authors: Salvatore Mele, David Dallman, Jens Vigen, Joanne Yeomans
Abstract: World-wide collaboration in high-energy physics (HEP) is a tradition which dates back several decades, with scientific publications mostly coauthored by scientists from different countries. This coauthorship phenomenon makes it difficult to identify precisely the ``share'' of each country in HEP scientific production. One year's worth of HEP scientific articles published in peer-reviewed journals is analysed and their authors are uniquely assigned to countries. This method allows the first correct estimation on a ``pro rata'' basis of the share of HEP scientific publishing among several countries and institutions. The results provide an interesting insight into the geographical collaborative patterns of the HEP community. The HEP publishing landscape is further analysed to provide information on the journals favoured by the HEP community and on the geographical variation of their author bases. These results provide quantitative input to the ongoing debate on the possible transition of HEP publishing to an Open Access model. - And finally, if you enjoyed the Rube-Goldberg machine made out of Honda parts, you might also like this video. I think, I finally found a purpose for all my CD's that are catching dust since iPod.
Wednesday, November 29, 2006
This and That
Christmas is coming closer, daylight is getting less and less, but except for one day in October we still haven't seen snow here in Waterloo. For once it seems I'm on the better side of climate change. What's interesting today:
Sunday, November 26, 2006
The Beauty of it All
I can't say I was drawn to theoretical physics because I found it utterly beautiful. Indeed, I found physics in middle school extremely confusing and ugly. We were essentially presented a set of equations, and asked to measure or compute things without any apparent reason. I definitely preferred mathematics, where things seemed to have a relation to each other, and were build up on well defined and reliable axioms.
I was lucky though that I had a very patient teacher who tried to explain me that all these equations actually can be derived from common principles, just that the maths necessary for this was missing in 8th grade. (E.g. the factor 1/2 in the equation s = 1/2 g t2 suddenly makes sense, when you learn what integration and differentiation is.) I realized only much later that in most of her explanations she was actually talking about differential equations, and the variational principle - what I would call one of the most beautiful concepts in physics.
Some weeks ago I read an article in the October issue of Scientific American Mind "The Neurology of Aesthetics", which investigated the neurological causes of what humans find beautiful. This post is a very free interpretation of the article, and a comparably free relation to beauty in physics, since I don't think it is necessary to have college level maths skills to see the beauty of it all.
Symmetry/Broken Symmetry
The SciAm article states that allegedly we are attracted to symmetry because it is a property of 'most biological objects' and 'it pays to have an early warning system to draw your attention to symmetry [...] This attraction explains symmetries allure [...]'. Which I can't really agree on, because symmetry apparently is a feature also of non living objects, whereas there exist 'biological' objects that are a) not symmetrical but worth paying attention (don't worry if you can't read the text, I'm still feeling slightly sick), or b) symmetrical but doubtful in their aesthetic value (don't click if you suffer from arachnophobia). But whatever the neurological reason, symmetry is mostly considered as beautiful, which is also the case in physics:
The pictures below show probability distributions of electrons in the hydrogen atom, as one can compute with elementary quantum mechanics (pictures drawn with this applet, if you want to play around).
For some real pictures, see e.g. the measurements of electron interference in high temperature superconductors at BNL.
The principle of symmetries finds its most powerful application in gauge symmetries, which are the foundation of the standard model of particle physics.
Patterns and Structures
The left picture above shows a piece of the Cosmic Microwave Background, the results from the WMAP measurements. From the sizes and colors (temperature fluctuation) of this pattern one can extract information about the structures at the time of radiation-matter equality.
Another example for structures in physics is closely connected to the search for a theory of quantum gravity. It is generally expected that at smallest scales (close by the Planck length) the spacetime we sit in is not a smooth background but quite messy and quantum foamy, see e.g. here for a picture and a brief introduction.
Less is More
Simplification is one of the primary goals in theoretical physics. Basically the whole search for a theory of everything can be thought of as a search for simplification. Some of the most compelling examples for a successful simplification are maybe the unification of (classical) electric and magnetic phenomena in Maxwell's equations, and the quantum field theory of electro-weak interactions.
But simplification is not only a goal. It is also an useful tool. Think about describing the properties of vapor. You don't compute the motions of every single atom, instead you describe the whole system by some few properties like temperature, pressure and volume.
Another well known example is considering the cow to be a sphere. This might be quite a crude approximation of you think about said cow as your next dinner. But If you want to describe, say, how a cow drops out of a plane and hit some innocent fisherman, it's completely appropriate to describe it as a sphere.
Simplification is also behind the cosmological principle, according to which the universe is roughly the same everywhere, and looks the same in every direction. This sounds pretty silly if you look at the screen in front of you, but makes sense if you think of galaxies as particles in a cosmic fluid. The CMB structures shown above are departures from this over-simplified description.
Besides being beautiful, simplification is an extremely powerful concept that can save a lot of brain time.
Amplification
The SciAm article refers to this as 'hypernormal stimuli': an amplified reaction to unusual modifications of a certain property, like high contrast colors, exaggerated shapes etc. They write 'We do not know why this effect occurs but it probably results from the way in which visual neurons encode sensory information' (Which imho is equivalent to saying they don't know anything.)
To come to theoretical physics, it seems that humans are just fascinated by strange thought experiments like: What would happen if you could travel at, or even faster than the speed of light? If you fell into a black hole? If the electron mass was only a bit larger? If space-time was made of braids? What if you'd try to microwave a marshmallow? Describe everything as tiny vibrating strings? What if you could fly? Travel back in time?
There's no doubt physicists like extremes.
Problem Solving
I was kind of surprised to see the SciAm article listing problem solving as a factor for beauty, the reason being 'When the correct fragments click into place, we feel a gratifying 'aha'.' This doesn't only make us like the picture whose 'problem we solved', but it is essentially what physics is all about: explaining the underlying concepts of things that look puzzling at first sight.
Another nice example for the fascination caused by problems are maybe also Esher's impossible pictures.
An additional point that doesn't relate to beauty in theoretical physics is that of a visual metaphor which draws its relevance from the historical and sociological context.
And if you want to get a perspective of how our concept of beauty is affected through the media, look at this video.
TAGS: SCIENCE, PHYSICS, BEAUTY
I was lucky though that I had a very patient teacher who tried to explain me that all these equations actually can be derived from common principles, just that the maths necessary for this was missing in 8th grade. (E.g. the factor 1/2 in the equation s = 1/2 g t2 suddenly makes sense, when you learn what integration and differentiation is.) I realized only much later that in most of her explanations she was actually talking about differential equations, and the variational principle - what I would call one of the most beautiful concepts in physics.
Some weeks ago I read an article in the October issue of Scientific American Mind "The Neurology of Aesthetics", which investigated the neurological causes of what humans find beautiful. This post is a very free interpretation of the article, and a comparably free relation to beauty in physics, since I don't think it is necessary to have college level maths skills to see the beauty of it all.
- 1. Symmetry/Broken Symmetry
2. Patterns and Structures
3. Less is More
4. Amplification
5. Problem Solving
Symmetry/Broken Symmetry
 |  |  |  |
The SciAm article states that allegedly we are attracted to symmetry because it is a property of 'most biological objects' and 'it pays to have an early warning system to draw your attention to symmetry [...] This attraction explains symmetries allure [...]'. Which I can't really agree on, because symmetry apparently is a feature also of non living objects, whereas there exist 'biological' objects that are a) not symmetrical but worth paying attention (don't worry if you can't read the text, I'm still feeling slightly sick), or b) symmetrical but doubtful in their aesthetic value (don't click if you suffer from arachnophobia). But whatever the neurological reason, symmetry is mostly considered as beautiful, which is also the case in physics:
 | There are the obvious examples of crystal growth (see here for more snowflakes) which are based on lattices. Then there is the power of symmetries to classify a confusing amount of particles: the quark model, a brilliant example of how symmetries (in this case SU(3)) allow to explain the observed particle zoo by building them up of only some few constituents. (See here for more info about the Eightfold Way). |
The pictures below show probability distributions of electrons in the hydrogen atom, as one can compute with elementary quantum mechanics (pictures drawn with this applet, if you want to play around).
 |  |  |
For some real pictures, see e.g. the measurements of electron interference in high temperature superconductors at BNL.
The principle of symmetries finds its most powerful application in gauge symmetries, which are the foundation of the standard model of particle physics.
However, as my mother likes to say 'Symmetrie ist die Kunst der Blöden.' -- 'Symmetry is the art of the poor.' Which is true in the sense that perfect symmetry is just boring. From the photos at the beginning of this section, none has perfect symmetry. The breaking of symmetries is essential to the formation of life. It is what makes nature an interesting place.
Patterns and Structures
 |  |  |
The left picture above shows a piece of the Cosmic Microwave Background, the results from the WMAP measurements. From the sizes and colors (temperature fluctuation) of this pattern one can extract information about the structures at the time of radiation-matter equality.
Another example for structures in physics is closely connected to the search for a theory of quantum gravity. It is generally expected that at smallest scales (close by the Planck length) the spacetime we sit in is not a smooth background but quite messy and quantum foamy, see e.g. here for a picture and a brief introduction.
Less is More
 |  |  |
Simplification is one of the primary goals in theoretical physics. Basically the whole search for a theory of everything can be thought of as a search for simplification. Some of the most compelling examples for a successful simplification are maybe the unification of (classical) electric and magnetic phenomena in Maxwell's equations, and the quantum field theory of electro-weak interactions.
But simplification is not only a goal. It is also an useful tool. Think about describing the properties of vapor. You don't compute the motions of every single atom, instead you describe the whole system by some few properties like temperature, pressure and volume.
Another well known example is considering the cow to be a sphere. This might be quite a crude approximation of you think about said cow as your next dinner. But If you want to describe, say, how a cow drops out of a plane and hit some innocent fisherman, it's completely appropriate to describe it as a sphere.
Simplification is also behind the cosmological principle, according to which the universe is roughly the same everywhere, and looks the same in every direction. This sounds pretty silly if you look at the screen in front of you, but makes sense if you think of galaxies as particles in a cosmic fluid. The CMB structures shown above are departures from this over-simplified description.
Besides being beautiful, simplification is an extremely powerful concept that can save a lot of brain time.
Amplification
 |  |  |
The SciAm article refers to this as 'hypernormal stimuli': an amplified reaction to unusual modifications of a certain property, like high contrast colors, exaggerated shapes etc. They write 'We do not know why this effect occurs but it probably results from the way in which visual neurons encode sensory information' (Which imho is equivalent to saying they don't know anything.)
To come to theoretical physics, it seems that humans are just fascinated by strange thought experiments like: What would happen if you could travel at, or even faster than the speed of light? If you fell into a black hole? If the electron mass was only a bit larger? If space-time was made of braids? What if you'd try to microwave a marshmallow? Describe everything as tiny vibrating strings? What if you could fly? Travel back in time?
There's no doubt physicists like extremes.
Problem Solving
I was kind of surprised to see the SciAm article listing problem solving as a factor for beauty, the reason being 'When the correct fragments click into place, we feel a gratifying 'aha'.' This doesn't only make us like the picture whose 'problem we solved', but it is essentially what physics is all about: explaining the underlying concepts of things that look puzzling at first sight.
Another nice example for the fascination caused by problems are maybe also Esher's impossible pictures.
An additional point that doesn't relate to beauty in theoretical physics is that of a visual metaphor which draws its relevance from the historical and sociological context.
And if you want to get a perspective of how our concept of beauty is affected through the media, look at this video.
Don’t the hours grow shorter as the days go by
We never get to stop and open our eyes
One minute you’re waiting for the sky to fall
The next you’re dazzled by the beauty of it all
TAGS: SCIENCE, PHYSICS, BEAUTY
Saturday, November 25, 2006
Isn't it nice...
... when things just work?
Look at this totally amazing Rube-Goldberg machine in a Honda ad:
"This Advertisement for the new Honda Accord was shot in real time with no CGI involved in the sequence. It required 606 takes and cost $6 million to shoot and took 3 months to complete.
The equipment was so precisely set up that the crew literally had to tip toe around the set for fear of disturbing things, which led to some unexpected problems. "As the day went on, the studio would get hotter," says Steiner. "It meant that the wood would expand and the cog or exhaust that spins around would move slightly faster." These tiny changes made big differences to the precision set-up of the equipment......
.....The sequence where the tires roll up a slope looks particularly impressive but is very simple. Steiner says that there is a weight in each tire and when the tire is knocked, the weight is displaced and in an attempt to rebalance itself, the tire rolls up the slope." source: steelcitysfinest.com
Look at this totally amazing Rube-Goldberg machine in a Honda ad:
"This Advertisement for the new Honda Accord was shot in real time with no CGI involved in the sequence. It required 606 takes and cost $6 million to shoot and took 3 months to complete.
The equipment was so precisely set up that the crew literally had to tip toe around the set for fear of disturbing things, which led to some unexpected problems. "As the day went on, the studio would get hotter," says Steiner. "It meant that the wood would expand and the cog or exhaust that spins around would move slightly faster." These tiny changes made big differences to the precision set-up of the equipment......
.....The sequence where the tires roll up a slope looks particularly impressive but is very simple. Steiner says that there is a weight in each tire and when the tire is knocked, the weight is displaced and in an attempt to rebalance itself, the tire rolls up the slope." source: steelcitysfinest.com
Thursday, November 23, 2006
More on AdS/CFT and RHIC
Last week, Pavel Kovtun gave a seminar here on PI about the AdS/CFT correspondence and its applications for RHIC physics. For a brief introduction, see e.g. our earlier post Does String Theory explain Heavy Ion Physics?. It was the same seminar that I heard at the KITP in spring, and on which I reported in the Banana-post. If you are interested in the topic, you can now download audio, video and slides from the PI streaming seminars:
It's not that I am so tremendously interested in the topic, I just find it remarkable how much fuss there is around it. Despite the fact that Pavel started his talk with a very nice motivation about RHIC experiments, I could not avoid noticing the sharp contrast between his predictions, and the predictions I am used to from nuclear physics talks. The latter of which usually include some plots of calculated observables, how well they fit the actual data points (and error bars to both if necessary). Based on this, a conclusion on the quality of the model should be given, and how they compare to other approaches. It seems to me that the AdS/CFT calculations haven't yet quite reached this state.
I have wondered for some while how the importance of the results is seen from the nuclear physicist's community, which has gathered last week in Shanghai on the Quark Matter 2006. The Quark Matter is the largest annual meeting of the community, which I am very sorry to have missed this year. But interestingly, yesterday a friend (who kindly agreed that I post his email) reported the following on the closing talk:
----- Original Message -----
From: "******* *******"
To: [...] sabine[@]perimeterinstitute.ca
Sent: Tuesday, November 21, 2006 9:00 PM
Subject: Tearing string theory a new a*hole
This is pretty weird/interesting.
We just concluded quark matter. At the theory summary, in what was supposed to be the closing session, the guy speaking (Larry McLerran, a pretty famous person) went on a 20 minute rant on string theory in general, attempts to use it to describe RHIC in particular, and Brian Greene in personal.
See Larry McLerran's talk (PPT), slides 19 onwards for what I am talking about (the slides do not convey his tone, e.g. giving Brian Greene a "Pinocchio award").
[...]
In any case, an amusing closing talk to conclude a somewhat politicized (no surprise) but fun (as always) conference.
[...]
------End of Original Message ---------
The powerpoint file is pretty large (11MB), so here are the last some slides as jpgs (click to enlarge), starting with the Pinocchio award for Brian Greene:
Please don't ask me details about the talk, as I mentioned, I didn't hear it. This is just to convey some skepticism from 'the other side'.
Update: See also Clifford's post Nuclear Guy goes Nuclear at Asymptotia, and Lubos' post Heavy Ion Physics and AdS/QCD.
Update: A written version of the summary talk is now available on the arxiv
Theory Summary: Quark Matter 2006
Authors: Larry McLerran
hep-ph/0702004
Title: How can AdS/CFT be useful for heavy-ion physics?
(Windows Media , Macromedia Flash , MP3 Audio , PDF)
Speaker(s): Pavel Kovtun
Date: 14/11/2006 - 11:00 am
It's not that I am so tremendously interested in the topic, I just find it remarkable how much fuss there is around it. Despite the fact that Pavel started his talk with a very nice motivation about RHIC experiments, I could not avoid noticing the sharp contrast between his predictions, and the predictions I am used to from nuclear physics talks. The latter of which usually include some plots of calculated observables, how well they fit the actual data points (and error bars to both if necessary). Based on this, a conclusion on the quality of the model should be given, and how they compare to other approaches. It seems to me that the AdS/CFT calculations haven't yet quite reached this state.
I have wondered for some while how the importance of the results is seen from the nuclear physicist's community, which has gathered last week in Shanghai on the Quark Matter 2006. The Quark Matter is the largest annual meeting of the community, which I am very sorry to have missed this year. But interestingly, yesterday a friend (who kindly agreed that I post his email) reported the following on the closing talk:
----- Original Message -----
From: "******* *******"
To: [...] sabine[@]perimeterinstitute.ca
Sent: Tuesday, November 21, 2006 9:00 PM
Subject: Tearing string theory a new a*hole
This is pretty weird/interesting.
We just concluded quark matter. At the theory summary, in what was supposed to be the closing session, the guy speaking (Larry McLerran, a pretty famous person) went on a 20 minute rant on string theory in general, attempts to use it to describe RHIC in particular, and Brian Greene in personal.
See Larry McLerran's talk (PPT), slides 19 onwards for what I am talking about (the slides do not convey his tone, e.g. giving Brian Greene a "Pinocchio award").
[...]
In any case, an amusing closing talk to conclude a somewhat politicized (no surprise) but fun (as always) conference.
[...]
------End of Original Message ---------
The powerpoint file is pretty large (11MB), so here are the last some slides as jpgs (click to enlarge), starting with the Pinocchio award for Brian Greene:
Please don't ask me details about the talk, as I mentioned, I didn't hear it. This is just to convey some skepticism from 'the other side'.
Update: See also Clifford's post Nuclear Guy goes Nuclear at Asymptotia, and Lubos' post Heavy Ion Physics and AdS/QCD.
Update: A written version of the summary talk is now available on the arxiv
Theory Summary: Quark Matter 2006
Authors: Larry McLerran
hep-ph/0702004
Wednesday, November 22, 2006
A Higher Dimensional Poem
These days, when I look out of my window and see the hazy shades of winter, I miss Santa Barbara! Especially so, because they used to distribute so pretty poems on their email list. Here is one I like best:
----- Original Message -----
From: "J****** T******"
To: "KITP Lunch List"
Sent: Wednesday, March 08, 2006 9:03 PM
Subject: [highdgr06] a poem
Welcome to the Gravity Party!
Once before
We thought there were 4
now instead
there may be 10
So drop the dread,
while 4 is NICE,
8 is TWICE,
And while 10 is good,
let it be understood,
Should we go by the letter,
or is 11 Better?
Then Why stop there?
should you care,
Let's add to the mix,
D= 666!
#############################################################
This message is sent to you because you are subscribed to
the mailing list highdgr06@kitp.ucsb.edu.
----- End of Original Message -----
----- Original Message -----
From: "J****** T******"
To: "KITP Lunch List"
Sent: Wednesday, March 08, 2006 9:03 PM
Subject: [highdgr06] a poem
Welcome to the Gravity Party!
Once before
We thought there were 4
now instead
there may be 10
So drop the dread,
while 4 is NICE,
8 is TWICE,
And while 10 is good,
let it be understood,
Should we go by the letter,
or is 11 Better?
Then Why stop there?
should you care,
Let's add to the mix,
D= 666!
#############################################################
This message is sent to you because you are subscribed to
the mailing list highdgr06@kitp.ucsb.edu.
----- End of Original Message -----
Saturday, November 18, 2006
Did you know... (II)
... that the Baconian method is suitable also for vegetarians?
Sir Francis Bacon, born 1561 in London, began his professional life as a lawyer, but became best known for his early investigations about the method of science, called the Baconian method. In case you had never heard from that guy before, here is what you definitely know:
It was Bacon was is who concluded
Scientia potentia est.
(Knowledge is Power.)
~Francis Bacon, Meditationes Sacrae, 1597
The Baconian method essentially suggests you clear up your mind from all prejudices before you try to do science (Idols of The Mind: Tribe, Cave, Marketplace, Theater), and then approach the issue constructively (pars construens) in three steps:
- The table of presence ("tabula praesentiae") lists all the cases wherein the phenomenon exists whose formal cause is sought [...]
- The table of absence ("tabula absentiae") lists all the cases in which the phenomenon under analysis does not appear to be present [...]
- The table of degrees ("tabula graduum") lists the increase and decrease of the given phenomenon in one object or in different objects.
This third table [...], should bring us to know the formal cause (law) of the phenomenon itself. It is not always easy to arrive at a formulation of the law [...]. In such a case we must be content with a temporary or working hypothesis, and await new instances, new experiments."
The recent results from high redshift supernovae, and the implications for our knowledge about the nature of dark energy (constraints on the equation of state), are a nice example for 'new instances' that can be included in the 'tables'. Hopefully, the new data will eventually allow us to extend our current 'working hypothesis'. So far, dark energy still is essentially a parametrization for some mysterious component of our universe whose origin we don't understand - but a parametrization which works annoyingly well! For more info about the new supernovae data, see Sean's post at CV or Clifford's post at Asymptotia.
But back to Sir Francis: early in the year 1626, he applied his method of scientific research to investigate the possibility of using snow to preserve meat. While stuffing the chicken with snow, he contracted a fatal case of pneumonia, and died on April, 9th 1626.
See also: Wikipedia on the Baconian method
TAGS: FRANCIS BACON, SCIENCE, BACONIAN METHOD, USELESS KNOWLEDGE
Hazy Shade of Winter
Yes, it's this time of the year again. Deadlines are approaching. And I'm enormously happy that this January I will not be sorting through letters saying 'Thank you for your interest in our theory group... We regret to inform you...'
If you are out on the market for position hunting, this post is especially for you: Good luck, don't give up!
TAGS: PHYSICS, JOBS
If you are out on the market for position hunting, this post is especially for you: Good luck, don't give up!
- Theoretical Particle Physics Jobs Rumor Mill
- Theoretical Particle Physics Postdoc Jobs Rumor Mill
- Astrophysics Job Rumor Mill
- Theoretical Nuclear Physics Rumor Mill
- "Time, time, time,
See whats become of me
While I looked around
For my possibilities
I was so hard to please
But look around,
leaves are brown
And the sky
Is a hazy shade of winter
[...]
Hang on to your hopes, my friend
That's an easy thing to say,
But if your hopes should pass away
Simply pretend
That you can build them again"
TAGS: PHYSICS, JOBS
Wednesday, November 15, 2006
Did you know...
10100 ,
which is a one followed by 100 zeros. It looks like this:
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000
The name 'googol' was invented by nine-year-old Milton Sirotta, the nephew of the American mathematician Edward Kasner, back in 1920.
The word was slightly scrambled, and used to name Google, to indicate the incredible high amount of information available on the web.
If you want to get an impression of how large a googol is, see what Schroeder had to say about that:
The name 'googol' was invented by nine-year-old Milton Sirotta, the nephew of the American mathematician Edward Kasner, back in 1920.
The word was slightly scrambled, and used to name Google, to indicate the incredible high amount of information available on the web.
If you want to get an impression of how large a googol is, see what Schroeder had to say about that:
But somewhere out there in the vast possibilities of the landscape, there are even universes in which Lucy got lucky...
TAGS: GOOGLE, GOOGOL, PEANUTS, USELESS KNOWLEDGE
NASA announces Discovery of Dark Energy...
NASA Schedules Dark Energy Discovery Media Teleconference
NASA will host a media teleconference with Hubble Space Telescope astronomers at 1 p.m. EST Thursday, Nov. 16, to announce the discovery that dark energy has been an ever-present constituent of space for most of the universe's history.
Reporters must call Ray Villard at the Space Telescope Science Institute Press Office, Baltimore, at: 410-338-4514 (villard@stsci.edu) or Cheryl Gundy at 410-338-4707 (gundy@stsci.edu) for participation information. Images and graphics about the research will be posted shortly before the start of the briefing at:
NASA will host a media teleconference with Hubble Space Telescope astronomers at 1 p.m. EST Thursday, Nov. 16, to announce the discovery that dark energy has been an ever-present constituent of space for most of the universe's history.
Reporters must call Ray Villard at the Space Telescope Science Institute Press Office, Baltimore, at: 410-338-4514 (villard@stsci.edu) or Cheryl Gundy at 410-338-4707 (gundy@stsci.edu) for participation information. Images and graphics about the research will be posted shortly before the start of the briefing at:
Briefing participants:
-- Adam Riess, astrophysicist, Space Telescope Science Institute and Johns Hopkins University, Baltimore
-- Mario Livio, senior astrophysicist, Space Telescope Science Institute
-- Louis-Gregory Strolger, astronomer, Western Kentucky University, Bowling Green, Ky.
-- Sean Carroll, senior research associate, California Institute of Technology, Pasadena, Calif.
Audio of the event will be available on the Internet at:
For NASA TV streaming video, schedule and downlink information, visit:
Tuesday, November 14, 2006
PS on Dark Matter
Two weeks ago, I reported on Stefan Hofmann's work about the influence of dark matter on the small scale structure of our universe. Last week, his collaborator Anne Green from the University of Nottingham gave a very good follow-up seminar on their work, and thanks to the new PI-websites, I can actually give you a link:
If you have the time and an interest in dark matter, you should invest the hour to look at it! During her talk, I noticed that in my earlier post I forgot to point out the important thing to notice in the figure below: the absence of even smaller structures in the magnification.
(picture from astro-ph/0501589)
TAGS: SCIENCE, PHYSICS, ASTROPHYSICS, COSMOLOGY, DARK MATTER
Dark matter: from the early Universe to the Milky Way
Speaker: Anne Green
Date: 11/07/2006, 2:00 PM CST
Length: 1 Hours, 5 Minutes, 46 Seconds
Abstract: The initial conditions for structure formation, and hence the dark matter distribution on sub-galactic scales, depend on the microphysics of the dark matter in the early Universe. I will focus on WIMPs and explain how collisional damping and free-streaming erase perturbations on comoving scales k> ~1/pc. Consequently the first structures to form in the Universe are mini-halos with mass of order the Earth. I will then describe the status of calculations of the subsequent dynamical evolution of these mini-halos. Finally, if time permits, I'll briefly overview the microphysics of axions.
If you have the time and an interest in dark matter, you should invest the hour to look at it! During her talk, I noticed that in my earlier post I forgot to point out the important thing to notice in the figure below: the absence of even smaller structures in the magnification.
(picture from astro-ph/0501589)
TAGS: SCIENCE, PHYSICS, ASTROPHYSICS, COSMOLOGY, DARK MATTER
Monday, November 13, 2006
Smoke came out of our theories...
Today I stumbled across the Honeywell Nobel Interactive Studio:
"[...] The Honeywell - Nobel Laureate Lecture Series [is] the centerpiece of a global education initiative designed to connect students across the globe with Nobel Prize winners in Chemistry and Physics. [...] A multi-year effort, the Honeywell – Nobel Initiative combines on-campus events, interactive webcontent and broadcast programming to link one generation of leading scientists with the development of the next."
Since I found out via NEW that these websites were only fairly recently launched, I want to encourage you to have a look at it. They have some very nice videos there. E.g. here is Leon Lederman, Nobel-Laureate in 1988, about the search for the Higgs:
"[...] and so far, no one has come up with a good alternative. But I suspect, there are some kids in junior high school [...] who will have within their minds the seeds of discovery... "
TAGS: PHYSICS, LHC, HIGGS
"[...] The Honeywell - Nobel Laureate Lecture Series [is] the centerpiece of a global education initiative designed to connect students across the globe with Nobel Prize winners in Chemistry and Physics. [...] A multi-year effort, the Honeywell – Nobel Initiative combines on-campus events, interactive webcontent and broadcast programming to link one generation of leading scientists with the development of the next."
Since I found out via NEW that these websites were only fairly recently launched, I want to encourage you to have a look at it. They have some very nice videos there. E.g. here is Leon Lederman, Nobel-Laureate in 1988, about the search for the Higgs:
"[...] and so far, no one has come up with a good alternative. But I suspect, there are some kids in junior high school [...] who will have within their minds the seeds of discovery... "
TAGS: PHYSICS, LHC, HIGGS
Sunday, November 12, 2006
Saturday, November 11, 2006
Hypocritical
hypocritical - professing feelings or virtues one does not have
Having been taught by Bert Schroer about the importance of irony and sarcasm in particle physics, I'd like to try an application of my newly won insights: Here is a rare case of an opportunity to learn from a world leader: George W. Bush and The Power of Words:
What I learn from this is that we should be wise and stop talking about whether or not we are looking for a 'Theory of Everything' by scanning over a whole landscape. Instead, we should bridge the increasing gaps in our community and rename our combined efforts into:
Theory of Everything Related Program Activities
PS: Nov 11th, at 11:11 am is the official begin of the Carnival Season in Germany.
TAGS: THEORY OF EVERYTHING, HUMOR, GEORGE W BUSH
Thursday, November 09, 2006
Lisa Randall on Discover
Today at 2pm the live-chat at discover.com with Prof. Lisa Randall from Harvard took place. It was a very balanced text interview in which Randall answered questions from the audience that were picked by the moderator (Amos Kenigsberg). He did a good job, it was interesting, and a lot of stuff was covered. As always, Lisa Randall was good in communicating her work.
Here are some of the more interesting questions (I wasn't able to copy and paste from the Java applet, so you'll have to endure screenshots). The person with name 'famous' is the moderator.
The first question was from someone called 'Xman':
In the answer I think Lisa Randall was referring to this paper on which I have commented in my post Why do we live in 3+1 dimensions.
As one would expect, there was a question about the LHC, and also one about the so-called string theory backlash:
She was also asked by 'qd_survivor' to comment on science blogging:
Anybody an idea what that guy was surviving? Here is my question, which I think she misunderstood:
(I don't know where these brackets come from, seems to be a software bug).
The question was whether string/loops/spin networks/other funny things out there can eventually turn out to be part of the same fundamental theory. And if mathematical consistency alone makes the fundamental theory unique. I agree on her answer, but it wasn't the answer to my question.
Besides this, I learned that the German version of her book 'Warped Passages' was just published. It seems to be one of the rare cases in which the German title 'Verborgene Universen' (hidden universes) makes sense, and imo is actually better than the English one.
A funny side remark: some time ago I piped a German research proposal through babelfish, which attempted as well to translate my reference list from German to English. The name Randall got 'translated' into Edge of the Universe. (Which is correct: the German word Rand means edge, and All is an expression for Universe.)
Update: Thanks to Georg, I found out that 'qd_survivor' has a post 'Two answers from Lisa Randall' on the blog A Quantum Diaries Survivor, where you also find a complete transcript of the chat.
TAGS: PHYSICS, LHC
Here are some of the more interesting questions (I wasn't able to copy and paste from the Java applet, so you'll have to endure screenshots). The person with name 'famous' is the moderator.
The first question was from someone called 'Xman':
In the answer I think Lisa Randall was referring to this paper on which I have commented in my post Why do we live in 3+1 dimensions.
As one would expect, there was a question about the LHC, and also one about the so-called string theory backlash:
She was also asked by 'qd_survivor' to comment on science blogging:
Anybody an idea what that guy was surviving? Here is my question, which I think she misunderstood:
(I don't know where these brackets come from, seems to be a software bug).
The question was whether string/loops/spin networks/other funny things out there can eventually turn out to be part of the same fundamental theory. And if mathematical consistency alone makes the fundamental theory unique. I agree on her answer, but it wasn't the answer to my question.
Besides this, I learned that the German version of her book 'Warped Passages' was just published. It seems to be one of the rare cases in which the German title 'Verborgene Universen' (hidden universes) makes sense, and imo is actually better than the English one.
A funny side remark: some time ago I piped a German research proposal through babelfish, which attempted as well to translate my reference list from German to English. The name Randall got 'translated' into Edge of the Universe. (Which is correct: the German word Rand means edge, and All is an expression for Universe.)
Update: Thanks to Georg, I found out that 'qd_survivor' has a post 'Two answers from Lisa Randall' on the blog A Quantum Diaries Survivor, where you also find a complete transcript of the chat.
TAGS: PHYSICS, LHC
Wednesday, November 08, 2006
This and That
- The 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2006) will be held in Shanghai, China on November 14-20, 2006. For more information, see their website.
- Christine Dantas has deleted most of her blog 'Background Independence'. It makes me very sad to see her go. For explanations, see 'Dantas is missing' at PF, or the comment section at Not Even Wrong. Update: Christine has put up a partial backup of her posts.
- Lee Smolin has a feature article in the November issue of Physics Today, titled 'Quantum Gravity faces Reality'. If you are registered, you can follow this link. It briefly explains attempts to measure effects of, and approaches to quantum gravity (String Theory, LQG, CDT, Spin Networks).
- The Perimeter Institute has finally launched the new websites!! They look great, they work better, and it's even possible to find the seminar you're looking for. Great job :-)
- Tomorrow, Thursday, Nov 9th at 2:00pm EST, there will be an online chat with theoretical physicist Lisa Randall at discover.com . Update: In case you have also wondered how this will work, see the email below.
- Lee Smolin has written a letter to friends and colleagues, regarding the ongoing discussion about his book. You find the letter on the website The Trouble with Physics.
----- Original Message -----
From: "Amos Kenigsberg" akenigsberg[@]discover.com
To: "Sabine Hossenfelder" sabine[@]perimeterinstitute.ca
Sent: Wednesday, November 08, 2006 7:02 PM
Subject: RE: One last thing
Dear Dr. Hossenfelder,
I'm the editor of Discover.com, and I'll be moderating the chat on Thursday. The event is going to be a real-time, online, text-based chat, with Lisa Randall as the guest and people interested in physics -- scientists and non-scientists -- as the audience. The chat will be on theoretical physics, centered around Lisa Randall's take on the field, and it will last for an hour.
At the beginning of the chat, I'm going to ask a few questions of Prof. Randall, and then we'll take questions from audience members. (I'll select the questions to make sure there's nothing offensive, way off-topic, or really dumb.) Anyone is welcome to comment and ask questions, but we want to keep things civil and generally accessible for lay people interested in science. Arguments with Randall's positions are perfectly welcome.
As for the technical side, chat readers and participants will need to have Java-enabled browsers. A regular household broadband connection would be great, and I'm not sure, but a dial-up connection might work fine, too. To enter the room, visitors will need to click on the button on this page:
http://www.discover.com/web-exclusives/lisa-randall-online-chat
As far as I know, running the JavaScript behind that button is the only way to get into the chat room. [The link will only activate when the chat room opens at around 1:50pm.]
Please let me know if you need to know anything else, and I hope to see you and your readers at the chat.
Sincerely,
Amos Kenigsberg.
* * * * * * * * * * * * *
Amos Kenigsberg
Web Editor
Discover Magazine
Tuesday, November 07, 2006
From a Distance...
... the world doesn't always look blue and green... flying over the earth today, I found quite amazing sand formations in Takla-Makan (Desert of Death), China, (click to enlarge).
TAGS: GOOGLE EARTH, DESERT
If you have Google Earth, you can download my placemark from the first location here, or look it up at Google-maps here. Also interesting: try this placemark, which seems to show some wheel traces in the desert that you can follow for endless miles.
Special thanks to Andi for the hint.
From a distance the world looks blue and green,
and the snow-capped mountains white.
From a distance the ocean meets the stream,
and the eagle takes to flight.
From a distance, there is harmony,
and it echoes through the land.
It's the voice of hope, it's the voice of peace,
it's the voice of every man [...]
From a distance you look like my friend,
even though we are at war.
From a distance I just cannot comprehend
what all this fighting is for.
TAGS: GOOGLE EARTH, DESERT
Sunday, November 05, 2006
Bubbles of Nothing
----- Original Message -----
From: "D**** S*****" ds*****[@]perimeterinstitute.ca
To: "Sabine Hossenfelder" sabine[@]perimeterinstitute.ca
Sent: Friday, November 03, 2006 1:19 PM
Subject: FedEx
Sabine,
There is a FedEx box at reception for you.
Come pick it up!
Thanks.
D*****
----- End of Message -----
To my surprise, the FedEx box turned out to be pretty large and heavy, with a sticker saying CUSTOMS CLEARED that covered the sender's address. After struggling with some kilometers of duck-tape, I exhibited my forwarded mail from the department at UCSB. I threw away a non-negligible amount of the usual advertisements, and was left with two large envelopes, in which there were further boxes, in which there were again envelopes.
One was from Houghton Mifflin, and contained the long awaited copy of Lee's book. But more interestingly, it came with an information sheet. Actually, it's not so much information but advertisement for some book that reveals allegedly shocking details about faith based science that penalized young physicists. It seems, I've read a different book. At least that explains the contents of many reviews I've seen since September, which basically repeat what's written on these accompanying pages. Well, the publisher know their job: ''In the coming months a heated debate raging on the Internet and at physics conferences is poised to break wide open, and THE TROUBLE WITH PHYSICS will serve as a rallying cry.''
Speaking of crying, I took off the book's cover, under which the book actually looks like a book, and not like a cleaning agent.
The other envelope contained the complete Particle Data Review, and the physicist's pocket diary, which is another step back to a normal life here in Waterloo.
Besides this, the box contained a significant amount of bubble wrap. With confused thoughts about valley-seekers or tree-climbers on the marketplace of ideas, and the backlashes of advertisement campaigns, I popped some bubbles.
I recalled that some months ago I read a story about the history of bubble wrap1. Bubble wrap was invented in 1957 in a garage in Somewhere, New Jersey, where the engineers Alfred Fielding and Marc Chavannes took two plastic curtains and ironed them together. The original intention for bubble wrap was to use it as a fancy and easy to clean wallpaper. Well. It seems, Americans are weird when it comes to interior decoration, but not completely nuts, so it didn't quite work out with the wallpaper idea. And if you've ever tried, you'd notice that bubble wrap isn't exactly easy to clean.
They then tried to market it as a greenhouse insulation, but that didn't work out either. It was only in 1960 that that they had the idea to use it as a wrapping for fragile items, in which it was very fast an enormous success. Marc and Alfred founded Sealed Air Corporation, and according to their website '[T]oday, Sealed Air is a leading global manufacturer of a wide range of food and protective packaging materials and systems with annual revenues in excess of 4 billion dollars.'
I love stories like this. They seem to capture such an essential part of the American spirit. This equally stubborn and arrogant conviction that you can make it if you only try hard enough. This equally naive and charming believe in your own ingenuity. This equally foolish and tough pursuit of new ideas2.
To add my European view, this story tells you also that the best advertisement isn't going to make bubbles of nothing into something they are not. And it tells you that sometimes it takes time until a good idea finds it's place in the world and can prove it's usefulness.
And what a sad place the world would be without bubble wrap!
I remember how my younger brother and I sat around popping bubbles. In some cases however, the air would only shift into the next closest bubble. As I learned from Wikepedia3, popping bubble wrap not merely silly, but actually a 'stress relieving activity'.
So, if you're troubled by physics or ideas that don't quite sell, how 'bout you pop some bubbles :-))
Footnote 1: After a lengthy period of mind twisting, I recalled that I read the story in an airline magazine. Obviously, that memory didn't include the name of the airline, the magazine, the title of the article, or its author. But thanks to Google, I was able to actually find the article I read: Smart Stuff, by Dan Gross, in the US Airways Magazine.
Footnote 2: This equally stupid and ignorant praise of the merits of capitalism.
Footnote 3: You also learn from Wiki that bubble wrap has an appearance in the song White and Nerdy by Al Yankovic, see also Clifford's post at Asymptotia.
TAGS: BUBBLEWRAP, IDEAS
From: "D**** S*****" ds*****[@]perimeterinstitute.ca
To: "Sabine Hossenfelder" sabine[@]perimeterinstitute.ca
Sent: Friday, November 03, 2006 1:19 PM
Subject: FedEx
Sabine,
There is a FedEx box at reception for you.
Come pick it up!
Thanks.
D*****
----- End of Message -----
To my surprise, the FedEx box turned out to be pretty large and heavy, with a sticker saying CUSTOMS CLEARED that covered the sender's address. After struggling with some kilometers of duck-tape, I exhibited my forwarded mail from the department at UCSB. I threw away a non-negligible amount of the usual advertisements, and was left with two large envelopes, in which there were further boxes, in which there were again envelopes.
One was from Houghton Mifflin, and contained the long awaited copy of Lee's book. But more interestingly, it came with an information sheet. Actually, it's not so much information but advertisement for some book that reveals allegedly shocking details about faith based science that penalized young physicists. It seems, I've read a different book. At least that explains the contents of many reviews I've seen since September, which basically repeat what's written on these accompanying pages. Well, the publisher know their job: ''In the coming months a heated debate raging on the Internet and at physics conferences is poised to break wide open, and THE TROUBLE WITH PHYSICS will serve as a rallying cry.''
Speaking of crying, I took off the book's cover, under which the book actually looks like a book, and not like a cleaning agent.
The other envelope contained the complete Particle Data Review, and the physicist's pocket diary, which is another step back to a normal life here in Waterloo.
Besides this, the box contained a significant amount of bubble wrap. With confused thoughts about valley-seekers or tree-climbers on the marketplace of ideas, and the backlashes of advertisement campaigns, I popped some bubbles.
I recalled that some months ago I read a story about the history of bubble wrap1. Bubble wrap was invented in 1957 in a garage in Somewhere, New Jersey, where the engineers Alfred Fielding and Marc Chavannes took two plastic curtains and ironed them together. The original intention for bubble wrap was to use it as a fancy and easy to clean wallpaper. Well. It seems, Americans are weird when it comes to interior decoration, but not completely nuts, so it didn't quite work out with the wallpaper idea. And if you've ever tried, you'd notice that bubble wrap isn't exactly easy to clean.
They then tried to market it as a greenhouse insulation, but that didn't work out either. It was only in 1960 that that they had the idea to use it as a wrapping for fragile items, in which it was very fast an enormous success. Marc and Alfred founded Sealed Air Corporation, and according to their website '[T]oday, Sealed Air is a leading global manufacturer of a wide range of food and protective packaging materials and systems with annual revenues in excess of 4 billion dollars.'
I love stories like this. They seem to capture such an essential part of the American spirit. This equally stubborn and arrogant conviction that you can make it if you only try hard enough. This equally naive and charming believe in your own ingenuity. This equally foolish and tough pursuit of new ideas2.
To add my European view, this story tells you also that the best advertisement isn't going to make bubbles of nothing into something they are not. And it tells you that sometimes it takes time until a good idea finds it's place in the world and can prove it's usefulness.
And what a sad place the world would be without bubble wrap!
I remember how my younger brother and I sat around popping bubbles. In some cases however, the air would only shift into the next closest bubble. As I learned from Wikepedia3, popping bubble wrap not merely silly, but actually a 'stress relieving activity'.
So, if you're troubled by physics or ideas that don't quite sell, how 'bout you pop some bubbles :-))
They even have twin bubbles :-))
And don't forget, Jan 27th is bubblewrap appreciation day...
Footnote 1: After a lengthy period of mind twisting, I recalled that I read the story in an airline magazine. Obviously, that memory didn't include the name of the airline, the magazine, the title of the article, or its author. But thanks to Google, I was able to actually find the article I read: Smart Stuff, by Dan Gross, in the US Airways Magazine.
Footnote 2: This equally stupid and ignorant praise of the merits of capitalism.
Footnote 3: You also learn from Wiki that bubble wrap has an appearance in the song White and Nerdy by Al Yankovic, see also Clifford's post at Asymptotia.
TAGS: BUBBLEWRAP, IDEAS
Feeling lucky?
Go to Google, search for 'failure', and hit the I'm-feeling-lucky-button. Or click here.
TAGS: GOOGLE
Some explanation on Googlebombing:
9/16/2005 12:54:00 PM
Posted by Marissa Mayer, Director of Consumer Web Products
If you do a Google search on the word [failure] or the phrase [miserable failure], the top result is currently the White House’s official biographical page for President Bush. We've received some complaints recently from users who assume that this reflects a political bias on our part. I'd like to explain how these results come up in order to allay these concerns.
Google's search results are generated by computer programs that rank web pages in large part by examining the number and relative popularity of the sites that link to them. By using a practice called googlebombing, however, determined pranksters can occasionally produce odd results. In this case, a number of webmasters use the phrases [failure] and [miserable failure] to describe and link to President Bush's website, thus pushing it to the top of searches for those phrases. We don't condone the practice of googlebombing, or any other action that seeks to affect the integrity of our search results, but we're also reluctant to alter our results by hand in order to prevent such items from showing up. Pranks like this may be distracting to some, but they don't affect the overall quality of our search service, whose objectivity, as always, remains the core of our mission.
TAGS: GOOGLE
Friday, November 03, 2006
50 Years Particle Data Group
Yesterday, I sorted through my mailbox at the institute, which revealed (besides several past due bills for my BlackBerry) an envelope from the Particle Data Group (PDG) with the new edition of the Particle Data Booklet. The booklet, which comes in a different color every year, is probably the most reliable companion of my postdoc life.
Besides all the known details about the elementary particles, and constraints on parameters in different models, it lists all these constants that theoretical physicists like to set equal to one, and things like the distance to the sun or the baryon density of the universe. But maybe most importantly, it contains the definitions of kinematical quantities (pseudo-rapidity, anybody?) and how to transform these from the lab frame in the center of mass frame and stuff like that. Besides this, it gives you the absolutely minimal introduction into the standard model.
I was kind of disappointed though because I also expected the complete review, and the 'particle physicist's pocket diary'. I usually put the booklet in the glove box of my car, and the review on my desk. The pocket diary has a good listing of physics institutes in the US, which is pretty handy for applications. But the only other thing the envelope contained was a brochure.
At first sight I thought it's one of these advertisements for vacuum pumps or likewise, but it turned out to be in honor of the 50th anniversary of the PDG. It has a lot of photos of the members of the group, and briefly tells the group's history. Apparently, earlier versions of the booklet had a ruler in inch and centimeter printed on it. The most amusing thing is what's written in the front flap:
In case you haven't yet noticed it, the PDG has now a website called PDGlive, which doesn't only list all the data, but has direct links to the references on SPIRES.
See also: PDG 50th anniversary festivities.
A nice weekend to all of you :-)
TAGS: PHYSICS, PARTICLE PHYSICS GROUP
Besides all the known details about the elementary particles, and constraints on parameters in different models, it lists all these constants that theoretical physicists like to set equal to one, and things like the distance to the sun or the baryon density of the universe. But maybe most importantly, it contains the definitions of kinematical quantities (pseudo-rapidity, anybody?) and how to transform these from the lab frame in the center of mass frame and stuff like that. Besides this, it gives you the absolutely minimal introduction into the standard model.
I was kind of disappointed though because I also expected the complete review, and the 'particle physicist's pocket diary'. I usually put the booklet in the glove box of my car, and the review on my desk. The pocket diary has a good listing of physics institutes in the US, which is pretty handy for applications. But the only other thing the envelope contained was a brochure.
At first sight I thought it's one of these advertisements for vacuum pumps or likewise, but it turned out to be in honor of the 50th anniversary of the PDG. It has a lot of photos of the members of the group, and briefly tells the group's history. Apparently, earlier versions of the booklet had a ruler in inch and centimeter printed on it. The most amusing thing is what's written in the front flap:
- A [...] problem occurred in the 1994 Booklet, so PDG thought it necessary to provide their readers with explanations as noted below.
The 'centimeters' on the ruler on p. 227 of the Booklet are 0.97 inches long, because:
- a) the booklets were returned from the printer at 0.25 times the speed of light;
b) A theorist is in charge of the Particle Data Group;
c) The PDG feels it has the right to redefine anything it wants;
d) There is a general decline of standards;
e) There was an international conspiracy;
f) It was a congressionally-mandated cost-saving measure;
g) PDG gives you more cm/inch than anyone else.
In case you haven't yet noticed it, the PDG has now a website called PDGlive, which doesn't only list all the data, but has direct links to the references on SPIRES.
See also: PDG 50th anniversary festivities.
A nice weekend to all of you :-)
TAGS: PHYSICS, PARTICLE PHYSICS GROUP