Closed source offline software used by millions Updated +Created
Closed source on offline products used by millions of people is evil, when you could just have those for free with open source software! Thus Ciro's hatred for Microsoft Windows and MacOS (at least userland, maybe).
tshark Updated +Created
Sample usage:
sudo tshark -f 'host 192.168.1.102
This produces simple one liners for each request.
What you likely want is the -V option which fully disassembles each frame much as you can do in the GUI Wireshark:
sudo tshark -V -f 'host 192.168.1.102
PyZX Updated +Created
1965 Nobel Prize in Physics laureate Updated +Created
Impenetrable Bose Gas Updated +Created
Explicit scalar form of the Maxwell's equations Updated +Created
For numerical algorithms and to get a more low level understanding of the equations, we can expand all terms to the simpler and more explicit form:
Cloud chamber Updated +Created
Figure 1.
Radium 226 source in a cloud chamber
. Source.
Video 1.
How to make a cloud chamber by Suzie Sheehy (2011)
Source.
64-bit architectures Updated +Created
64 bits is still too much address for current RAM sizes, so most architectures will use less bits.
x86_64 uses 48 bits (256 TiB), and legacy mode's PAE already allows 52-bit addresses (4 PiB). 56-bits is a likely future candidate.
12 of those 48 bits are already reserved for the offset, which leaves 36 bits.
If a 2 level approach is taken, the best split would be two 18 bit levels.
But that would mean that the page directory would have 2^18 = 256K entries, which would take too much RAM: close to a single-level paging for 32 bit architectures!
Therefore, 64 bit architectures create even further page levels, commonly 3 or 4.
x86_64 uses 4 levels in a 9 | 9 | 9 | 9 scheme, so that the upper level only takes up only 2^9 higher level entries.
The 48 bits are split equally into two disjoint parts:
----------------- FFFFFFFF FFFFFFFF
Top half
----------------- FFFF8000 00000000


Not addressable


----------------- 00007FFF FFFFFFFF
Bottom half
----------------- 00000000 00000000
A 5-level scheme is emerging in 2016: software.intel.com/sites/default/files/managed/2b/80/5-level_paging_white_paper.pdf which allows 52-bit addresses with 4k pagetables.
Ciro Santilli Myers-Briggs Type Indicator Updated +Created
Ciro Santilli feels that Ciro Santilli Myers-Briggs Type Indicator is much more random/hard to determine than the Big Five personality traits
Upon a quick look Ciro Santilli evaluates himself as INTJ.
PAE Updated +Created
Physical address extension.
With 32 bits, only 4GB RAM can be addressed.
This started becoming a limitation for large servers, so Intel introduced the PAE mechanism to Pentium Pro.
To relieve the problem, Intel added 4 new address lines, so that 64GB could be addressed.
Page table structure is also altered if PAE is on. The exact way in which it is altered depends on weather PSE is on or off.
PAE is turned on and off via the PAE bit of cr4.
Even if the total addressable memory is 64GB, individual process are still only able to use up to 4GB. The OS can however put different processes on different 4GB chunks.
Quantum interconnect Updated +Created
"Quantum interconnect" refers to methods for linking up smaller quantum processors into a larger system.
As of 2024, seemingly few organizations developing quantum hardware had actually integrated multiple chips in interconnects as part of their main current roadmap. But many acknowledged that this would be an essential step towards scalable compuation.
The name "quantum interconnect" is likely partly a throwback to classical computer's "chip interconnect".
Sample usages of the term:
2012 Internet Census icmp_ping Updated +Created
Let's check relevancy of known hits:
grep -e '208.254.40' -e '208.254.42' 208 | tee 208hits
Output:
208.254.40.95	1355564700	unreachable
208.254.40.95	1355622300	unreachable
208.254.40.96	1334537100	alive, 36342
208.254.40.96	1335269700	alive, 17586

..

208.254.40.127	1355562900	alive, 35023
208.254.40.127	1355593500	alive, 59866
208.254.40.128	1334609100	unreachable
208.254.40.128	1334708100	alive from 208.254.32.214, 43358
208.254.40.128	1336596300	unreachable
The rest of 208 is mostly unreachable.
208.254.42.191	1335294900	unreachable
...
208.254.42.191	1344737700	unreachable
208.254.42.191	1345574700	Icmp Error: 0,ICMP Network Unreachable, from 63.111.123.26 
208.254.42.191	1346166900	unreachable
...
208.254.42.191	1355665500	unreachable
208.254.42.192	1334625300	alive, 6672
...
208.254.42.192	1355658300	alive, 57412
208.254.42.193	1334677500	alive, 28985
208.254.42.193	1336524300	unreachable
208.254.42.193	1344447900	alive, 8934
208.254.42.193	1344613500	alive, 24037
208.254.42.193	1344806100	alive, 20410
208.254.42.193	1345162500	alive, 10177
...
208.254.42.223	1336590900	alive, 23284
...
208.254.42.223	1355555700	alive, 58841
208.254.42.224	1334607300	Icmp Type: 11,ICMP Time Exceeded, from 65.214.56.142 
208.254.42.224	1334681100	Icmp Type: 11,ICMP Time Exceeded, from 65.214.56.142 
208.254.42.224	1336563900	Icmp Type: 11,ICMP Time Exceeded, from 65.214.56.142 
208.254.42.224	1344451500	Icmp Type: 11,ICMP Time Exceeded, from 65.214.56.138 
208.254.42.224	1344566700	unreachable
208.254.42.224	1344762900	unreachable
Let's try with 66. First there way too much data, 9 GB, let's cut it down:
n=66
time awk '$3~/^alive,/ { print $1 }' $n | uniq -c | sed -r 's/^ +//;s/ /,/' | tee $n-up-uniq-c
OK down to 45 MB, now we can work.
grep -e '66.45.179' -e '66.104.169' -e '66.104.173' -e '66.104.175' -e '66.175.106' '66-alive-uniq-c' | tee 66hits
Nah, it's full of holes:
4,66.45.179.187
12,66.45.179.188
2,66.45.179.197
1,66.45.179.202
2,66.45.179.205
2,66.45.179.206
1,66.45.179.207
won't be able to find new ranges here.
Controlled quantum gate Updated +Created
Controlled quantum gates are gates that have two types of input qubits:
These gates can be understood as doing a certain unitary operation only if the control qubits are enabled or disabled.
The first example to look at is the CNOT gate.
Figure 1. . Source.
The black dot means "control qubit", and "U" means an arbitrary Unitary operation.
When the operand has a conventional symbol, e.g. the Figure "Quantum NOT gate symbol" for the quantum NOT gate to form the CNOT gate, that symbol is used in the operand instead.
Cabbage (Csound) Updated +Created
2.5.0 manual prebuilt download install on Ubuntu 20.04 just worked. Launch directly from unzip without install. Play with examples under install/Examples
Their docs are a reasonable way to learn Csound: cabbageaudio.com/docs/introduction/
History of the World Wide Web Updated +Created
Video 1.
Why web tech is like this by Steve Sanderson (2022)
Source.
CEA Updated +Created
Toffoli gate Updated +Created
Mathematician Updated +Created
Poet, scientists and warriors all in one? Conquerors of the useless.
A wise teacher from University of São Paulo once told the class Ciro Santilli attended an anecdote about his life:
I used to want to learn Mathematics.
But it was very hard.
So in the end, I became an engineer, and found an engineering solution to the problem, and married a Mathematician instead.
It turned out that, about 10 years later, Ciro ended up following this advice, unwittingly.
Figure 1.
xkcd 435: Fields arranged by purity
. Source.

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