This is what happens when you apply a DC voltage across a Josephson junction.
It is called "AC effect" because when we apply a DC voltage, it produces an alternating current on the device.
By looking at the Josephson equations, we see that a positive constant, then just increases linearly without bound.
Therefore, from the first equation:we see that the current will just vary sinusoidally between .
This meas that we can use a Josephson junction as a perfect voltage to frequency converter.
Wikipedia mentions that this frequency is , so it is very very high, so we are not able to view individual points of the sine curve separately with our instruments.
Also it is likely not going to be very useful for many practical applications in this mode.
An I-V curve can also be seen at: Figure "Electron microscope image of a Josephson junction its I-V curve".
I-V curve of the AC Josephson effect
. Source. 
Voltage is horizontal, current vertical. The vertical bar in the middle is the effect of interest: the current is going up and down very quickly between , the Josephson current of the device. Because it is too quick for the oscilloscope, we just see a solid vertical bar.
The non vertical curves at right and left are just other effects we are not interested in.
TODO what does it mean that there is no line at all near the central vertical line? What happens at those voltages?
Superconducting Transition of Josephson junction by Christina Wicker (2016)
Source. Amazing video that presumably shows the screen of a digital oscilloscope doing a voltage sweep as temperature is reduced and superconductivity is reached.
Their only undergraduate courses that matter:
- www.brookes.ac.uk/courses/undergraduate/biological-sciences-mbiol/ (archive)
- www.brookes.ac.uk/courses/undergraduate/mathematics/ should be called applied mathematics (archive)
Creator of QEMU and FFmpeg, both of which Ciro Santilli deeply respects. And a bunch other random stuff.
What is shocking about Fabrice this is that both are insanely important software that Ciro Santilli really likes, and both seem to be completely unrelated subjects!
Google made billions on top of this dude:
- FFmpeg is the backend of YouTube
- QEMU is the default emulator for Android Studio as of 2019, which Android developers use by default under the hood to develop Android Apps on their desktop without the need for a real device.
At last but not least, Fabrice also studied in the same school that Ciro Santilli studied in France, École Polytechnique.
It is a shame that he keeps such a low profile, there are no videos of him on the web, and he declines interviews.
Another surprising fact is that Fabrice has not worked for the "Big Tech Companies" as far as can be publicly seen, but rather mostly on smaller companies that he co-founded: www.quora.com/Computer-Programmers/Computer-Programmers-Where-is-Fabrice-Bellard-employed
And he's also into some completely random projcts unsurprisingly:
- www.computerhistory.org/tdih/january/6/ Computer Scientist Fabrice Bellard Announces Computing Pi to Record Number of Digits
Bibliography:
- smartbear.com/de/blog/2011/fabrice-bellard-portrait-of-a-super-productive-pro/ contains a list of his projects as of 2011
Fabrice Bellard in 2007
. Source. At a restaurant with the author apparently. Plus Miguel De Icaza who was in Paris for some conference, which they all presumably attended.
Fabrice Bellard with light
. There are no in-focus images of Fabrice on the Internet.The second protein to have its structure determined, after myoglobin, by X-ray crystallography, in 1965.
Breaks up peptidoglycan present in the bacterial cell wall, which is thicker in Gram-positive bacteria, which is what this enzyme seems to target.
Part of the inate immune system.
20 minutes in optimal conditions, with a crazy multiple start sites mechanism: E. Coli starts DNA replication before the previous one finished.
Otherwise, naively, would take 60-90 minutes just to replicate and segregate the full DNA otherwise. So it starts copying multiple times.
- biology.stackexchange.com/questions/30080/how-can-e-coli-proliferate-so-rapidly
- stochasticscientist.blogspot.co.uk/2012/02/how-e-coli-grows-so-fast.html
- www.ncbi.nlm.nih.gov/pmc/articles/PMC2063475/ Organization of sister origins and replisomes during multifork DNA replication in Escherichia coli by Fossum et al (2007)
With X-ray crystallography by David Chilton Phillips. The second protein to be resolved fter after myoglobin, and the first enzyme.
Published at: Structure of Hen Egg-White Lysozyme: A Three-dimensional Fourier Synthesis at 2 Å Resolution (1965). The work was done while at the Davy Faraday Research Laboratory of the Royal Institution.
Phillips also published a lower resolution (6angstrom) of the enzyme-inhibitor complexes at about the same time: Structure of Some Crystalline Lysozyme-Inhibitor Complexes Determined by X-Ray Analysis At 6 Å Resolution (1965). The point of doing this is that it points out the active site of the enzyme.
The CNOT gate is a controlled quantum gate that operates on two qubits, flipping the second (operand) qubit if the first (control) qubit is set.
This gate is the first example of a controlled quantum gate that you should study.
CNOT gate symbol
. Source. The symbol follow the generic symbol convention for controlled quantum gates shown at Figure "Generic controlled quantum gate symbol", but replacing the generic "U" with the Figure "Quantum NOT gate symbol".
To understand why the gate is called a CNOT gate, you should think as follows.
First let's produce a generic quantum state vector where the control qubit is certain to be 0.
On the standard basis:we see that this means that only and should be possible. Therefore, the state must be of the form:where and are two complex numbers such that
If we operate the CNOT gate on that state, we obtain:and so the input is unchanged as desired, because the control qubit is 0.
If however we take only states where the control qubit is for sure 1:
Therefore, in that case, what happened is that the probabilities of and were swapped from and to and respectively, which is exactly what the quantum NOT gate does.
So from this we understand more concretely what "the gate only operates if the first qubit is set to one" means.
Now go and study the Bell state and understand intuitively how this gate is used to produce it.
As of 2022, this channel is still finding its feet. But it has promise.
Unfortunately it does not show sample preparation, and it does not use controlled cultures, so we are never sure which species are represented.
TODO possible? superuser.com/questions/559768/ffplay-how-to-play-together-separate-video-and-audio-files
For synthesized streams like but it does not seem to accept multiple fails with:
sine we can do it e.g.ffplay -autoexit -nodisp -f lavfi -i '
sine=frequency=500[a];
sine=frequency=1000[b];
[a][b]amerge, atrim=end=2
'-i for some reason. So is there a way to open a file from some filter? E.g.:ffplay -i tmp.wav -i tmp.mkv -filter_complex "[0:a]atrim=end=2[a];[1:v]trim=end=2[v]" -map '[a]' -map '[v]'Argument 'tmp.mkv' provided as input filename, but 'tmp.wav' was already specified.Section type:
sh_type == SHT_RELA.Common name: "relocation section".
.rela.text holds relocation data which says how the address should be modified when the final executable is linked. This points to bytes of the text area that must be modified when linking happens to point to the correct memory locations.Basically, it translates the object text containing the placeholder 0x0 address:to the actual executable code containing the final 0x6000d8:
a: 48 be 00 00 00 00 00 movabs $0x0,%rsi
11: 00 00 004000ba: 48 be d8 00 60 00 00 movabs $0x6000d8,%rsi
4000c1: 00 00 00It was pointed to by
sh_info = 6 of the .symtab section.readelf -r hello_world.o outputs:Relocation section '.rela.text' at offset 0x3b0 contains 1 entries:
Offset Info Type Sym. Value Sym. Name + Addend
00000000000c 000200000001 R_X86_64_64 0000000000000000 .data + 0The section does not exist in the executable.
The actual bytes are:
00000370 0c 00 00 00 00 00 00 00 01 00 00 00 02 00 00 00 |................|
00000380 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|The
struct represented is:typedef struct {
Elf64_Addr r_offset;
Elf64_Xword r_info;
Elf64_Sxword r_addend;
} Elf64_Rela;So:
- 370 0:
r_offset= 0xC: address into the.textwhose address this relocation will modify - 370 8:
r_info= 0x200000001. Contains 2 fields:ELF64_R_TYPE= 0x1: meaning depends on the exact architecture.ELF64_R_SYM= 0x2: index of the section to which the address points, so.datawhich is at index 2.
The AMD64 ABI says that type1is calledR_X86_64_64and that it represents the operationS + Awhere:S: the value of the symbol on the object file, here0because we point to the00 00 00 00 00 00 00 00ofmovabs $0x0,%rsiA: the addend, present in fieldr_added
This address is added to the section on which the relocation operates.This relocation operation acts on a total 8 bytes. - 380 0:
r_addend= 0
So in our example we conclude that the new address will be:
S + A = .data + 0, and thus the first thing in the data section.This is opposed to messages that may be left by non miners during transactions.
Miner messages are therefore of course much harder to control on established blockchains, as they basically require consensus in a mining pool to set. Most of them are just ads for the mining pool itself.
Published by Werner Heisenberg in 1925-07-25 as quantum mechanical re-interpretation of kinematic and mechanical relations by Heisenberg (1925), it offered the first general formulation of quantum mechanics.
It is apparently more closely related to the ladder operator method, which is a more algebraic than the more analytical Schrödinger equation.
It appears that this formulation makes the importance of the Poisson bracket clear, and explains why physicists are so obsessed with talking about position and momentum space. This point of view also apparently makes it clearer that quantum mechanics can be seen as a generalization of classical mechanics through the Hamiltonian.
QED and the men who made it: Dyson, Feynman, Schwinger, and Tomonaga by Silvan Schweber (1994) mentions however that relativistic quantum mechanics broke that analogy, because some 2x2 matrix had a different form, TODO find that again.
Inward Bound by Abraham Pais (1988) chapter 12 "Quantum mechanics, an essay" part (c) "A chronology" has some ultra brief, but worthwhile mentions of matrix mechanics and the commutator.
Advantages of fog: there is only one, reusing hardware that would be otherwise idle.
Disadvantages:
- in cloud, you can put your datacenter on the location with the cheapest possible power. On fog you can't.
- on fog there is some waste due to network communication.
- you will likely optimize code less well because you might be targeting a wide array of different types of hardware, so more power (and time) wastage. Furthermore, some of the hardware used will not not be optimal for the task, e.g. CPU instead of GPU.
All of this makes Ciro Santilli doubtful if it wouldn't be more efficient for volunteers simply to donate money rather than inefficient power usage.
Bibliography:
- greenfoldingathome.com/2018/05/28/is-foldinghome-a-waste-of-electricity/: useless article, does not compare to centralize, asks if folding the proteins is worth the power usage...
norm sequence convergence does not imply pointwise convergence Updated 2024-12-23 +Created 1970-01-01
There are explicit examples of this. We can have ever thinner disturbances to convergence that keep getting less and less area, but never cease to move around.
If it does converge pointwise to something, then it must match of course.
The Quora question: www.quora.com/Are-there-any-PhD-programs-in-training-an-AI-system-to-play-computer-games-Like-the-work-DeepMind-do-combining-Reinforcement-Learning-with-Deep-Learning-so-the-AI-can-play-Atari-games
A good way to find labs is to go down the issues section of projects such as:and then stalk them to see where they are doing their PhDs.
AGI research has become a taboo in the early 21st century Updated 2024-12-23 +Created 1970-01-01
Due to the failures of earlier generations, which believed that would quickly achieve AGI, leading to the AI winters, 21st researchers have been very afraid of even trying it, rather going only for smaller subste problems like better neural network designs, at the risk of being considered a crank.
While there is fundamental value in such subset problems, the general view to the final goal is also very important, we will likely never reach AI without it.
This is voiced for example in Superintelligence by Nick Bostrom (2014) section "Opinions about the future of machine intelligence" which in turn quotes Nils Nilsson:
There may, however, be a residual cultural effect on the AI community of its earlier history that makes many mainstream researchers reluctant to align themselves with over-grand ambition. Thus Nils Nilsson, one of the old-timers in the field, complains that his present-day colleagues lack the boldness of spirit that propelled the pioneers of his own generation:Nilsson’s sentiment has been echoed by several others of the founders, including Marvin Minsky, John McCarthy, and Patrick Winston.Concern for "respectability" has had, I think, a stultifying effect on some AI researchers. I hear them saying things like, "AI used to be criticized for its flossiness. Now that we have made solid progress, let us not risk losing our respectability." One result of this conservatism has been increased concentration on "weak AI" - the variety devoted to providing aids to human
thought - and away from "strong AI" - the variety that attempts to mechanize human-level intelligence
Don't be a pussy, AI researchers!!!
Unlisted articles are being shown, click here to show only listed articles.