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Ed Hartouni
Trad climber
Livermore, CA
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May 27, 2010 - 03:08am PT
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The Physics of Frank Sacherer
delivered by Ed Hartouni at the Frank Sacherer Remembrance, May 22, 2010, Yosemite Valley, CA.
Jan has asked me to explain to you the physics that Frank Sacherer did in his life and she has given me 15 minutes to do it in. Perhaps you can imagine the difficulty if you imagine trying to explain Frank's climbs to an audience of non-climbers. However, physicists believe that if you understand your physics you can explain it to a bar maid. I've actually attempted this several times, the results are always the same; the next morning when upon waking with a hangover you realize the bar maid was better at her job than you were at your's.
How Sacherer came to study the physics of particle accelerators is not known to me. I looked in his 1968 thesis and in his "Acknowledgement" chapter we find no clues. The only clue really is Jan's observation that Frank liked what we call "Classical Electrodynamics," and U.C. Berkeley, and the Lawrence Berkeley Laboratory, often referred to as the "Rad Lab," were the center of particle accelerators in the 60s, so maybe it is not too strange to think that Sacherer would pursue his physics interest in an exciting area like particle physics. But not the part about the particles, about the parts of how to get the particles to move.
I can't possibly describe in detail what particle physics is, what it tries to study. But the method that we use is age old, we bang two things together hard enough so that they brake apart. The component parts go spraying all over, we collect them and try to figure out how the things we broke are built. This involves relativistic quantum field theory, sophisticated experimental apparatus, and particle accelerators. And what we are braking apart will tell us how the universe is constructed, at least in terms of the material universe that is the object of a physicist's study.
One way we brake things, particles like protons and electrons, apart is to get them going at a high speed, close to the speed of light and then arrange to have them collide. The particle accelerator does the job of accelerating the particles to those speeds.
These accelerators work because the particles have electric charge, and we arrange a situation in which they are attracted to by opposite charges.
Climbers know about this, they have mass, the Earth has a bigger mass, gravity will accelerate the climber, attracting the climber towards it. This works fine until the surface of the Earth intervenes and stops the climber's motion.
So falling is one to accelerate, but the nature of falling from a cliff and hitting the ground isn't the best way to accelerate to high velocities. Perhaps if you drilled a hole through the center of the earth and jumped in... if you could neglect the drag due to the air it would take you 8 hours to return to where you dropped in, because the pull of gravity that accelerates you on the way to the center of the earth, de-accelerates you as you move away from the center of the earth... where you are moving at the brisk pace of roughly 4 times the speed of sound.
Surfers, skate boarders, skiers, skydivers have all figured out a way to fall but never hit the ground. The surfers are the most interesting case.
Surfers paddle their boards to get going about as fast as a wave is passing by and then drop down the front side of the wave. The surfer than matches the speed of the wave, falling as fast as the wave is moving, by maneuvering on the wave. The wave is moving, and so is the surfer. This is how a particular type of accelerator works. You may have seen such an accelerator if you drive on interstate-280 around Palo Alto you see the Stanford Linear Accelerator going by. There electrons surf the radio frequency electromagnetic waves, accelerating in a straight line.
If you can imagine a surfer catching a wave that travels around the world, then you can imagine the type of accelerator that Frank studied, one in which the particles, in his case protons, are turned in a circular path by a magnetic field. There are many magnets arranged around a circle to do this, and the magnets have different functions, some to turn the protons, some to focus them on their path. When there are only a few protons everything works out fine. But you run into problems when you have a lot of them, and you need a lot of protons to do the physics.
These protons travel in bunches just like surfers catching different waves in a set of waves, the surfers will be found on the leading edge of the waves, as the protons are found on the leading edge of the electromagnetic waves. Now if you try to squeeze the protons too close together they start to repel each other, same for the surfers. They spread out loosing their bunchieness.
That may work for surfers, but it isn't good for particle accelerators. We say the particle bunch becomes unstable.
Frank's work dealt with understanding the instability of particle beams as they circulated around the accelerator's circumference, his particular contribution was in the theory of longitudinal instability, like what happens if you have so many surfers on a wave that there are surfers in front of and behind each other. To make it even more challenging, as the particles go around the accelerator, the pass the same magnets over and over again, and if there are imperfections in the way the magnets are placed, the effect of the imperfection can build up over time, and eventually lead to the beam being lost. How this happens is like being on a swing. You start out just sitting there. If you kick your feet you start to swing a little. Then you kick your feet at just the right time, you can swing a bit more, you keep doing this until you are swinging a lot. Those kicks are timed to be in resonance with the particular swing you're on, and if you were a bunch of particles, you'd be all over the place.
The best bunch is something that has as many particles in it that you can manage, and the smallest cross sectional area you can achieve. In these conditions, the instabilities of the beam are the greatest.
After going to CERN, the European Center for Nuclear Research and currently the home of the largest accelerator that has been built, Frank worked on the basic theory of these instabilities. His work systematically categorized them, and became of great use to the accelerator physicists designing the next generation of machines for the next big physics experiments at the time. Even his getting a job at CERN was extraordinary, at the time American's did not have an easy time getting an appointment, CERN was created to rebuild European science after World War II with restrictions on the participation of physicists from the United States.
In his work at CERN he derived the fundamental formula describing these instabilities, now referred to as the "Sacherer Integral" which in some ways is like having a climb named after you, say the "Sacherer Cracker" or as we call it today "Sacherer Crack." These integrals were the result of his looking at the phenomena and extracting the essential physical characteristics, then deriving the mathematical descriptions governing the motion of these bunches of particles traveling in the accelerators.
In the late 70s he started to lay out the theory of a technique that an accelerator engineer, Simon van der Meer, devised to keep the protons in line. The idea was that you could measure the position of the protons at one point of the ring, and as they were spinning along the circumference of the accelerator, you could send that information to some actuators by a short cut, say along the diameter of the circle, in time to kick the protons back into the right distribution. We call it "cooling the beam" and it goes by the name of "stocastic cooling." This allowed the creation of beams with very large numbers of protons, and very small cross sectional areas. Frank worked out the theory for this idea, an important contributions since it was unknown whether or not the beams would be stable to the "kicking."
This lead to the creation of two very large accelerators, one at Fermilab and one at CERN that raced to find an important particle, found at CERN. The importance of this particle was recognized with a Nobel Prize, and very unusually, van der Meer, who thought up "stocastic cooling," was a co-recipient. In his Nobel address he recognizes Frank's contribution, this after Frank's death.
Frank's papers are still cited by accelerator physicists who are studying and designing accelerators. That is the best recognition that a physicist could have, that his work outlives himself. Just like in climbing, we can still climb Frank's climbs in Yosemite Valley, and get a sense of his climbing contribution, we actually measure our own abilities against his list of climbs here.
Frank's physics insights continue to contribute to our understanding of the universe, laying an important piece of the foundational knowledge required to build the accelerators we use to probe the universe.
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guido
Trad climber
Santa Cruz/New Zealand/South Pacific
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May 27, 2010 - 11:32am PT
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Thank you Ed for offering this simplification of a most complex topic that now even I can comprehend.
It was great to see old friends and meet new ones and share some stories of the past. Kudos to Jan, Ken and Steve for putting this together.
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guido
Trad climber
Santa Cruz/New Zealand/South Pacific
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May 29, 2010 - 11:57am PT
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Ed
The first photo is John with Steve Moyles.
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Ed Hartouni
Trad climber
Livermore, CA
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May 29, 2010 - 12:25pm PT
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Cragman, "Steve ?" is Steve Grossman in the photo above
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Rick A
climber
Boulder, Colorado
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May 31, 2010 - 09:41am PT
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Ed and company,
Thanks for your reports on this event. I wish that I could have been there to celebrate Sacherer and his contemporaries. The event looks like it was a fitting conclusion to Ed's original Sacherer thread, which is a marvel.
Rick
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Mighty Hiker
climber
Vancouver, B.C.
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May 31, 2010 - 06:51pm PT
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Roger and John at our dinner at the Mountain Room, Monday evening. John apparently looking forward to a change from macaroni & cheese.
Did you know that Canadians eat the most Kraft dinner per capita of any nation?
Steve and ParkRat. Suzie provided a rather interesting perspective on Bridwell's sartorial tastes.
ParkRat's friend/neighbour Judy, with Rik. Judy may have found the weather, a tent cabin at Curry, and us climbers a bit much, but was game for an adventure. (I believe they later visited relatives on the coast, somewhere warm and sunny.)
Ed Whittle, doing what he does so well.
A word from one of the sponsors. One bottle was given to each person present who knew Frank Sacherer or Jim Baldwin (or both), with a few left over for special guests.
More photos later - waiting to hear from Steve if I went to the right place.
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donini
Trad climber
Ouray, Colorado
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May 31, 2010 - 07:49pm PT
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Thanks for the photos MH, wish I could have been there.
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Jan
Mountain climber
Okinawa, Japan
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Topic Author's Reply - Jun 1, 2010 - 06:21am PT
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I just got back to Okinawa.
Sorry we missed the get together in the Mountain Room. Hope and I finally found a motel room in Merced at 3 am after the memorial and then just drove on to the Bay Area the next day. After that I was incommunicado at a Buddhist retreat center.
More to be said after I recover from my 23 hour journey back to Japan!
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Chicken Skinner
Trad climber
Yosemite
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Jan,
Just received this picture of Frank today taken by Tony Qamar.
Ken
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Lynne Leichtfuss
Sport climber
Will know soon
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Trekking to No Cal in May I met Phil Bone and his wife Constance. Phil is a bitd climber as well as a talented carpenter and wood worker ..... he's just started painting. I bought one of his first works. Hopefully he will have a piece to auction off at the YCA fund raiser in July. One very talented Dude.
Entered the Valley of Wow to Honor Frank Sacherer and the birth of spring in one of the most awe inspiring places on earth. ( At least for me.)
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Lynne Leichtfuss
Sport climber
Will know soon
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Met many climbers from back in the day who were kind enough to share the richness of the communities history with me.
Pat Ament
Hope Meek signing my Yosemite Climber Book. Hope was one of the first women to climb in the Valley.
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Mighty Hiker
climber
Vancouver, B.C.
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Roger at the east auditorium. He was saying "I'm Roger Breedlove, and I'm badass" to Ed and Steve. Hence their reaction.
In Roger's hands, the much-autographed copy of Yosemite Climber, eventually to be auctioned for a good cause.
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Clint Cummins
Trad climber
SF Bay area, CA
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Lynne,
I think you meant Hope was one of the relatively rare women climbers in Yosemite in the late 50s/early 60s. Not one of the very first ever.
Sarah Dutcher climbed Half Dome in 1875.
above photo is Sarah L. Dutcher.
http://www.stanford.edu/%7Egalic/history/halfdome/index.html
"Freddy" Hubbard did Washington Column Direct in 1947.
And several women climbed in Yosemite in the intervening time.
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Lynne Leichtfuss
Sport climber
Will know soon
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Jason Wilson from CO was a fun person to meet. He was kind enough to extend a climbing invitation to lynnie for a unique bouldering area. Thanks Jason ! :D
and it was cool to see " the Bridge Mon" there
as well as "history man" Steve Grossman....missed you big time Mimi !!!
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Lynne Leichtfuss
Sport climber
Will know soon
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Ja, Clint ..... Hope told me she was one of the first women in her generation to climb in Yo Valley. Good to know there were others before her and then with her. Not many tho. :D
Edit: Freddy Hubbard is bad a. If she can climb Washingtons Column and Half Dome in that Outfit......I have alot of Hope. :DD Seriously !!!!
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Clint Cummins
Trad climber
SF Bay area, CA
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Lynne,
Did Hope say which climbs she did?
P.S. That photo I posted was Sarah L. Dutcher, around 1875, not Freddy Hubbard in 1947. I relabelled it - maybe clearer now?
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Lynne Leichtfuss
Sport climber
Will know soon
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Clint, let me reflect what she said...... It's late and I'll post rest of pics manana now that I have my new computer under pic posting control thanks to all yo out there.
Clint, I do know the one thing she emphasized was that she had to pretty much beg guys to let her go along on the climbs. I guess yo could be hard core and say why didn't she just do it herself, but cut the gal slack....she attempted a solo on the Golden Gate Bridge. :D
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JOEY.F
Social climber
sebastopol
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Nice to have been there for the Friday night showing of Deciples of Gill. Good to see you Lynne. Just barely crossed paths with Ed and Jo, Ed H., Anders...Not able to go the Memorial on Sat, oh well, good vibes, good times. Paths will cross again, no doubt.
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Lynne Leichtfuss
Sport climber
Will know soon
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Ja, hope so Joey. Are you able to be part of this years Facelift ?
Yo must be famous ...... everyone seems to know you. I thought you were Joey F. like I am Lynne L. Just a regular ST'er.
Is it the pickles you won't give out the receipe for ? Are they like Joey's famous pickles ? The number 1 Fortune 500 Dill. "Jess wonderin'" like Jingy would say. Kiddin' around and a little dopey cause it's past my legal bedtime.
Peace Dude and have a Gute Nacht. :D
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Roger Breedlove
climber
Cleveland Heights, Ohio
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Hey Anders, I think the line is "I'm Mark Hudon and I'm badass," our mantra to get up the hard parts.
I was able to collect more signatures for Marty's signature book project-- Jan Sacherer (edited--see below) for Frank, John Stannard, Bonny Kamps for Bob, Gary and Reva Colliver, Eric Beck, Dick Erb, Jeff Dozier, Glen Denny, Joe McKeon, John Dill, Werner Braun, Mike Lichlinski, Dean Potter, Dean Fidelman. Steve Grossman had Tom Frost sign when he visited him after the weekend.
Alpinist will run a photo montage of the book in the up-coming issue on the Off Belay.
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