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sun_q
Trad climber
NY
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Topic Author's Original Post - Apr 21, 2007 - 01:41am PT
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Hi all,
I think I'm beginning to understand Einstein's frustration with the mechanics of quantum physics; in particular Heisenberg's Uncertainty Principle.
"Uncertainty" is a bit of a misnomer. You cannot know both the *exact* velocity and *exact* position of a particle at the same time. Equivalently: the more accurately you measure velocity, the less accurately you can measure position, and vice versa. (This is why 'uncertainty' is a misnomer, since Heisenberg calculates, with certainty, what the trade-off must be.)
And so much for all that...
The point here is that we seem to have:
The more equalized you make your anchor, the less 'non-extententable' it is (think a collection of 'sliding Xs'. Conversely, the more 'non-extententable your anchor, the less equalized (back to Cordalette.)
JL's uncertainty principle?
But onto the specific topic of this post.
JL's new anchors book demonstrates the imperfectability of the cordalette by pointing out that a piece, say, one foot away, will carry more load than a piece, say three feet away. Just on account of the slack of any rope.
Now, JL's proposed equallete. Assume we've got three pieces--A, B, & C--to be rigged by an equallete. Assume all are bomber, but A in particular will hold a truck. So you attach one end to A, and the other to B & C (clove hitched, or sliding X'd, or whatever.)
The Mistake??? Assuming full equalization, don't we have 50% of the weight on A, and the other 50% of the weight on B&C??? Isn't this precisely why a 'perfect' cordalete isn't as good as an equallete?
I know that angles & distances affect weight, but the central point remains: One pieces in this setup is bearing more of the load. Even with limiter knots, if it goes, then we've got extension.
The JL error?
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Ed Hartouni
Trad climber
Livermore, CA
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Apr 21, 2007 - 02:14am PT
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sun_q
didn't you read John's response in one of your other threads?
this seems like just a troll...
...the two limits are the cordelette and the sliding-x
the sliding-x will equalize if the sling is free to slide, you can figure out lots of different ways to do this when the number of anchors is larger than 2.
The problem with extensibility with the sliding-x get's less with more anchors, but the friction increases, defeating the equalization at some point. The real problem, however, is a single point failure, the sling breaking.
All other systems I've seen are "between" these two. There is no solution to the problem with the stuff we've been given to figure it out.
Take to heart Karl's plea to drop the analysis and just work on getting good anchors. While I think that theoretical rigor revealed this situation long ago, few found the arguments accessible...
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