Quantum statistics Updated +Created
Quaternion Updated +Created
Kind of extends the complex numbers.
Some facts that make them stand out:
DigitalDreamDoor Updated +Created
Ahh, this brings good memories of Ciro Santilli's musical formative teenage years scouring the web for the best art humanity had ever produced in certain generes. And it still is a valuable resource as of the 2020's!
numpy/fft.py Updated +Created
Output:
sin(t)
fft
real 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
imag 0 -10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10
rfft
real 0 0 0 0 0 0 0 0 0 0 0
imag 0 -10 0 0 0 0 0 0 0 0 0

sin(t) + sin(4t)
fft
real 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
imag 0 -10 0 0 -10 0 0 0 0 0 0 0 0 0 0 0 10 0 0 10
rfft
real 0 0 0 0 0 0 0 0 0 0 0
imag 0 -10 0 0 -10 0 0 0 0 0 0
With our understanding of the discrete Fourier transform we see clearly that:
qiskit/hello.py Updated +Created
Our example uses a Bell state circuit to illustrate all the fundamental Qiskit basics.
Sample program output, counts are randomized each time.
First we take the quantum state vector immediately after the input.
input:
state:
Statevector([1.+0.j, 0.+0.j, 0.+0.j, 0.+0.j],
            dims=(2, 2))
probs:
[1. 0. 0. 0.]
We understand that the first element of Statevector is , and has probability of 1.0.
Next we take the state after a Hadamard gate on the first qubit:
h:
state:
Statevector([0.70710678+0.j, 0.70710678+0.j, 0.        +0.j,
             0.        +0.j],
            dims=(2, 2))
probs:
[0.5 0.5 0.  0. ]
We now understand that the second element of the Statevector is , and now we have a 50/50 propabability split for the first bit.
Then we apply the CNOT gate:
cx:
state:
Statevector([0.70710678+0.j, 0.        +0.j, 0.        +0.j,
             0.70710678+0.j],
            dims=(2, 2))
probs:
[0.5 0.  0.  0.5]
which leaves us with the final .
Then we print the circuit a bit:
qc without measure:
     ┌───┐
q_0: ┤ H ├──■──
     └───┘┌─┴─┐
q_1: ─────┤ X ├
          └───┘
c: 2/══════════

qc with measure:
     ┌───┐     ┌─┐
q_0: ┤ H ├──■──┤M├───
     └───┘┌─┴─┐└╥┘┌─┐
q_1: ─────┤ X ├─╫─┤M├
          └───┘ ║ └╥┘
c: 2/═══════════╩══╩═
                0  1
qasm:
OPENQASM 2.0;
include "qelib1.inc";
qreg q[2];
creg c[2];
h q[0];
cx q[0],q[1];
measure q[0] -> c[0];
measure q[1] -> c[1];
And finally we compile the circuit and do some sample measurements:
qct:
     ┌───┐     ┌─┐
q_0: ┤ H ├──■──┤M├───
     └───┘┌─┴─┐└╥┘┌─┐
q_1: ─────┤ X ├─╫─┤M├
          └───┘ ║ └╥┘
c: 2/═══════════╩══╩═
                0  1
counts={'11': 484, '00': 516}
counts={'11': 493, '00': 507}
react/ref-click-counter.html Updated +Created
Dummy example of using a React ref This example is useless and to the end user seems functionally equivalent to react/hello.html.
It does however serve as a good example of what react does that is useful: it provides a "clear" separation between state and render code (which becomes once again much less clear in React function components.
Notably, this example is insane because at:
<button onClick={() => {
  elem.innerHTML = (parseInt(elem.innerHTML) + 1).toString()
we are extracing state from some random HTML string rather than having a clean JavaScript variable containing that value.
In this case we managed to get away with it, but this is in general not easy/possible.
Huainanzi Updated +Created
Potassium Updated +Created
Emotion Updated +Created
Film about artificial intelligence Updated +Created
And by artificial intelligence, read of course (non-human-identical) artificial general intelligence.
Today-2022, this is placed under the science fiction film category. But maybe this might change during Ciro Santilli's own lifetime?
The basic criteria of "is a film about artificial intelligence good or not" to Ciro Santilli is: does the AI inhabit humanoid, or fully human looking, bodies? Bodies is a bad sign due to:
  • the best science fiction works deeply explore the consequences of one single technology: efficient humanoid bodies are a second technological breakthrough besides AI itself. The first AI will obviously be a supercomputer without a body
  • it is hard to imagine that the AI wouldn't organize itself as one huge central computer and R&D/command center. Perhaps there will be need for a few separate ones to optimize usage of natural resources, and to have some redundance in case a nuke blows the region, but there would be very very few of the think tanks. But having big centers is fundamental, because you centralize all the flow of ideas and their combination leading to new better outcomes for the AI. The mobile robot actors controlled by this center, if any exist, would then be slaves with some degree of autonomy and infinitely less computational powerful than the think tank.
Finite field Updated +Created
A convenient notation for the elements of of prime order is to use integers, e.g. for we could write:
which makes it clear what is the additive inverse of each element, although sometimes a notation starting from 0 is also used:
For fields of prime order, regular modular arithmetic works as the field operation.
For non-prime order, we see that modular arithmetic does not work because the divisors have no inverse. E.g. at order 6, 2 and 3 have no inverse, e.g. for 2:
we see that things wrap around perfecly, and 1 is never reached.
For non-prime prime power orders however, we can find a way, see finite field of non-prime order.
Video 1.
Finite fields made easy by Randell Heyman (2015)
Source. Good introduction with examples
Finite projective linear group Updated +Created
First They Ignore You Updated +Created
First They Ignore You, Then They Laugh at You, Then They Attack You, Then You Win
Quora Updated +Created
Quora is crap in many, many senses, but in part due to some bad Stack Overflow policies, it is the best crap we've got for certain (mostly useless) subjects. Until OurBigBook.com dominates the world.
The worst thing about quora is that you cannot subscribe only to certain subjects on your feed. Quora just keeps pumping shit you never subscribed to, no matter what. Ciro, for sport, unfollowed every single idiotic subject it was proposing, but it didn't work, sooner or later Quora just keeps pumping more shit back. Mind you, some of that shit is fun. But it's still shit. Though on second thought, YouTube also randomly decides to reset Ciro's humongous "don't recomend this shitty channel" choices from time to time, which is not much different...
Other terrible things, they just seem to have an incredible ability of making the website worse and more annoying over time! Truly amazing:
Quora is getting so bad that it is basically being killed by Reddit, especially after they lifted the 6-month hard thread lock...
See also: cirosantilli.com/china-dictatorship/quora for a coverage of the intense pro-CCP astroturfing present on the website.
Ciro Santilli's hardware / Polytechnique USB flash drives Updated +Created
~8GB, lsblk reports 7796176 * 1KB = 7983284224 bytes.
We got a handful of those from École Polytechnique at the end of studies I think.
They are shaped like bicornes, which is super cool, but also super impractical!
Markings: "AX ÉCOLE POLYTECHNIQUE PROMOTION X2009"
20.04 gnome-disks program reports it as: "SMI USB DISK".
From Ubuntu 20.04 on an ext4 formatted one:
/dev/sdb:
 Timing cached reads:   28656 MB in  1.99 seconds = 14421.31 MB/sec
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 Timing buffered disk reads:  42 MB in  3.03 seconds =  13.88 MB/sec
With Linux Unified Key Setup + ext4 the results are similar, maybe hdparam bypasses it?
/dev/sdb:
 Timing cached reads:   28326 MB in  1.99 seconds = 14251.55 MB/sec
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 Timing buffered disk reads:  38 MB in  3.11 seconds =  12.23 MB/sec
gnome-disks LUKS + ext4 benchmark with default params also gives about 14 MB/s.
Flagellum Updated +Created
Flux qubit Updated +Created
In Ciro's ASCII art circuit diagram notation, it is a loop with three Josephson junctions:
+----X-----+
|          |
|          |
|          |
+--X----X--+
https://upload.wikimedia.org/wikipedia/en/0/04/Flux_Qubit_-_Holloway.jpg
Video 1.
Superconducting Qubit by NTT SCL (2015)
Source.
Offers an interesting interpretation of superposition in that type of device (TODO precise name, seems to be a flux qubit): current going clockwise or current going counter clockwise at the same time. youtu.be/xjlGL4Mvq7A?t=1348 clarifies that this is just one of the types of qubits, and that it was developed by Hans Mooij et. al., with a proposal in 1999 and experiments in 2000. The other type is dual to this one, and the superposition of the other type is between N and N + 1 copper pairs stored in a box.
Their circuit is a loop with three Josephson junctions, in Ciro's ASCII art circuit diagram notation:
+----X-----+
|          |
|          |
|          |
+--X----X--+
They name the clockwise and counter clockwise states and (named for Left and Right).
When half the magnetic flux quantum is applied as microwaves, this produces the ground state:
where and cancel each other out. And the first excited state is:
Then he mentions that:
  • to go from 0 to 1, they apply the difference in energy
  • if the duration is reduced by half, it creates a superposition of .
Focal length Updated +Created
If you pass parallel light.
For a biconvex spherical lens, it is given by:
where:
  • n: f nidnex
Football Updated +Created
Football is a synonym for association football, can we be done with that! The word "soccer" is an aberration.
B Reactor Updated +Created
Reactor of the Hanford site of the produced the plutonium used for Trinity and Fat Man.
This was the first full scale nuclear reactor in the world, and was brought up slowly to test it out.
Video 1.
Hanford B Reactor tour by Studio McGraw
. Source. 2016.

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