Then would that make the photon the only real subatomic particle?How neat would it be if every subatomic particle was just a closed-form EM field of a different shape?
No. It would make the EM field fundamental to all of physics. This is my take, not the video's author.Then would that make the photon the only real subatomic particle?
I can't watch the video.
Too bad. It's a good one.I can't watch the video.
Yeah, but then what is the EM field made up of?No. It would make the EM field fundamental to all of physics. This is my take, not the video's author.
Gravity.Yeah, but then what is the EM field made up of?
Descriptive set theorists study the niche mathematics of infinity. Now, they’ve shown that their problems can be rewritten in the concrete language of algorithms.
One key outcome of this approach is the ability to derive exact formulas for kernel functions. These include the Green, Neumann, and Schwarz kernels, which are important tools for solving boundary value problems in physics and engineering. By linking geometric patterns with analytical formulas, the research bridges intuitive visual thinking and rigorous mathematical precision.
Hello there,
Hi,
Tang presented a classical algorithm that matched the speed of its quantum version. She showed that if both normal and quantum computers had similar ways to access data, the quantum computer’s speed advantage disappeared.
That's interesting. The access problem had always bugged me.EDIT: I'd like to mention that this post could also easily belong to the Quantum Computing thread.
Hi,
Hello again,
I've seen a lot of beautiful formulas and expressions because I had to use a lot of them in the past. Maybe the best one was for calculating sine or cosine without using a series. You started with a guess, and it converged very quickly and got better approximations with each pass, and each pass produced twice as many digits.
However, I had used that with a very old Basic interpreter that only did sines and cosines in single precision, and when I went to the more modern computer platforms like Windows and even MS DOS, I abandoned the algorithm because I always got double precision which was good enough at the time. Years later, I was building up a big number library and low and behold, I could not find the algorithm again no matter where I looked. To compound the frustration, I actually developed the algorithm myself starting with the idea that if you had computed the inverse sine from the computed value of sine, you could zero in on the sine better and better by comparing the two.
In other words compute sine of 'angle1' to some degree of accuracy where sin() here is a numerical approximation so 'a1' is an approximate numerical result:
a1=sin(angle1)
then using that actual a1 compute inverse sine:
angle2=inverse_sine(a1)
then by comparing angle1 and angle2 in 'some' way, we can zero in on the exact value of a1 given the number of required digits.
The really beautiful part is the number of accurate digits approximately doubles for each 'pass'.
For example, if the exact sin(angle1) was 0.1234567890123456 to that many digits, and the first pass produced 0.12, then the second pass would produce 0.1234, and the third pass 0.12345678, and the fourth pass would produce the entire 16 digits. There was also a little bit of overhead though to condition angle1 and then angle2 also, but I seem to have forgotten almost everything else about it. This I did originally in the 1980's so it was a very long time ago. The other frustrating part is I had told someone here in this forum about it and even how to develop it, but I can't even remember who it was now.
I tried multiple attempts to recover it from the original idea, but I can't even remember if I followed through with that idea above or if something else came out of it that made me switch to a different route.
Talk about frustration. I even fired up my very very old TRS80 computer because that is where I used it long ago, but despite searching over 50 floppy disks (5.25 inch size), could not find it.
I've thus sort of given up on finding it but may try to develop it again at some point.
Funny, 'ai' does give very odd results. It gives formulas that don't work, keeps correcting them when told they don't work but still does not produce one that works, then the next day says it cannot be done. I tried for several hours to try to recover it that way too (ha ha).
Could I have remembered it wrong, that it did not produce double the number of digits with each pass?
Well I remember well that it was not a series, and that you had to start with a guess, and a short table of starting values would speed up the first approximation. With a series you don't start with a guess.
This is not Newton–Raphson on sin(x). It is Newton–Raphson on the functional equation:Use your approximate sine value to compute an arcsine, compare it to the original angle, and use that discrepancy to correct the sine.
The correction step is what gives you digit‑doubling.
Because Newton’s method is quadratically convergent when the derivative is well‑behaved.Each iteration roughly doubles the number of correct digits.
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