Category Archives: colossus
We learn that depths provided sufficient evidence to figure the chi and psi wheel patterns – which were changing quarterly or monthly, only. And , we know that before the machine age of GCCS really got going that this change … Continue reading
Having been away from 1950s cryptanalysis for a few weeks has helped – in the sense that we come to the material now somewhat refreshed; able to see connections that we missed. In particular, we look at expander graphs – … Continue reading
it turns out useful to go re-review some of our year 3 curriculum on coding, channels, sampling, decibels etc now we that have the perspective afforded to use in studying year 4 topics. Our math is strong enough now to … Continue reading
http://tetrahedral.blogspot.com/2011/01/gino-fano-and-fano-plane.html Suddenly realized why Turing, in On Permutations, was so focussed originally on wanting his subgroup to have terms that sum to zero. One sees, from the bit-focused example built into the fano plane, how te test for point … Continue reading
think of the overstrung piano.
spread. concentration. ration of arithmetic to geometric.
use of argmin and an accumulator for 85% ness. Cutoff filters.
third moment. symmetry.
fourth moment. comparing to normal, with normal being 3.
jitter – variation in successive peaks.
counting softs vs louds.
measure of noise-ness – or the percussiveness of the sound field. Think spinet vs piano.
strength, vs power or energy. Also, the most norm-ish.
interesting project of the musical 12 semitones onto a 3 donuts, corresponding to the variations in the major and minor modes to the tonic chord. Basically, major to minor detector (that is a little like the crossing zeros…)
rather than power, look at energy. Look at the 12 keys on the piano octave… Note the immunity of a particular detector (the ear) to noise, when the harmonics have the right musical quality.
Building on the centroid, to note how power disperses beyond the “inner circle of the 7 point geometry).
working in “power” thinking.
This is the core of the Colossus-assisted attack on Tunny, of course.
In one of this “theoretical minimum” lectures, Susskind goes through what he thinks of as elementary presentations about the linkup between boolean algebra and quantum mechanics. He is showing that there is an ordering to the evaluation of an (non-exclusive) … Continue reading
Physics Research InternationalVolume 2010 (2010), Article ID 808424, 18 pageshttp://dx.doi.org/10.1155/2010/808424 Research Article The Statistical Origins of Quantum Mechanics U. Klein Institut für Theoretische Physik, Johannes Kepler Universität Linz, 4040 Linz, Austria
When we looked at the Tunny sqaure in the General Report (circa 1945), we quickly figured that it was related to the 4 –operator Klein Group. (It sticks out!…) https://yorkporc.wordpress.com/2011/09/08/bigger-klein-groups-using-tunnys-addition-square/ I see now how I need to improve the … Continue reading
see http://quasirandomideas.wordpress.com/2010/04/28/walsh-functions-i-orthonormality-and-completeness/ instead of omega.b to a power, read b (omega) conjugated by a (the power). Turing
Comparing des sbox design theory with Colossus-era language about proportional bulges, reliability metrics, and walsh transforms of bulge functions.
It’s fun to compare modern language of cryptanalysis with that used in the Colossus era. Perhaps the best cipher-engineering paper I’ve ever read uses that language aiming to justify how to resist DES-era cryptanalysis in a special case. This elaboration … Continue reading
Reading the following ICA based on a Smooth Estimation of the Differential EntropyLev Faivishevsky, Jacob Goldberger, School of Engineering, Bar-Ilan University See http://machinelearning.wustl.edu/mlpapers/paper_files/NIPS2008_0513.pdf I found myself translating. Recovering latent variables felt like “tunny wheel breaking.” Observations of unknown linear functions … Continue reading
Lakshmi Bala, NPTEL See http://freevideolectures.com/Course/3213/Quantum-Mechanics-I She does a good point of teaching what an idealistic Turing at 18 would have been learning, about Kennard’s quantum mechanics. Note how “Tunny-like” it is (with delta’ing). One even sees elements of the “algebra … Continue reading
In the papers on war-time enigma attach methods, Turing discloses how he originally calculated odds factors. That is, for an assumed urn-style sequence of experiments (abstracting guesses to be made about unknown contents of German naval enigma bigram tables for … Continue reading
Sometimes things click, as they did for me tonight. Something I read in the Tunny report (on how Colossus was used in the attack on Tunny ciphering machine) never made much sense – in that I could not find modern … Continue reading
http://www.nsa.gov/public_info/_files/cryptologs/cryptolog_105.pdf written 1986 – on the heyday of the pre-collapse NSA (of the early 1990s) – you can hear the self-confident tone. One gets an interesting data point. Note how the writer contrasts decoding of the code generators underlying … Continue reading