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Norman Wildberger has an alternative system for trigonomtry:

Understanding uniform motion: are radians really necessary? | WildTrig

https://youtu.be/CnQXRdgN_7I?si=EiYY99i6mBOIyczI

Wild Trig: An introduction to Rational Trigonometry

https://youtube.com/playlist?list=PLIljB45xT85CyF_7bKd6y36VA...


Where were you when Infantino was selling football to private corporations that implement VAR? The fundamental and defining property of football was that it was played in real time. Referee whistled and that was it. Now decisions are made far away by individuals looking at screens.


> The fundamental and defining property of football

Are you sure it's not that you use your foot to manipulate a ball?


> However now a neo-Pythagorian doctrine is emerging, according to which everything is 0/1 bits, and the world is built entirely out of digital information

Can this be true? DNA is the information system of living creatures and as far as I know, it is not coded with 0s and 1s. So, how can we justify that "the world is built entirely out of digital information"?


For all I, a Victorian everyman, know the world is built from small pistons, gears and pulleys.

Every age has their technology which they will project onto the world. A century ago one may have started to talks about everything being electrical wires and switches.


It doesn't matter whether the model assumes bits, pulleys, elves or whatever, as long as it does a better job at describing physical reality than whatever exists at the time anyway. People will try and very probably succeed in providing alternative formalism anyway.

All that matters is whether it facilitates reasoning towards the goal.


I read all the comments in the times post and no one mentions that this is due to the motion of the Artemis II. On the moon there is no "earthrise" or "earthset", only a yearly wobble. On the earth the moon rises and sets because of the earth's rotation. I guess the editors of the NYT knew this so that they put the "earthset" in quotes.


I use nano a lot but this page is not opening for me. Is someone else having the same problem?


I was able to open it in archive


A beautiful book by Michel Pastoureau, Blue: The History of a Color (2001), the same content as the article in book form.

https://www.amazon.com/Blue-History-Color-Michel-Pastoureau/...


See also: a philosophical and lyrical take, "Bleuets" by Maggie Nelson (2019).


More detailed video of Plimpton 322 from the authors of the paper https://youtu.be/L24GzTaOll0?si=sNdwKiM7uYXbzVfL


I tried but his pages do not have links to a home page or other posts


There's this https://susam.net/pages.html for your convenience. (Also this https://susam.net/links.html maybe a bit more organised.)


It looks like they chose to use the "universal gravitational constant" "k" instead of Newton^s constant, "G": p.23, "k^2 = universal gravitational constant, 1.32452139x10^20, m^3/(sec^2)(sun mass units)"

I think "k" was also known as "Gaussian gravitational constant" https://en.wikipedia.org/wiki/Gaussian_gravitational_constan...

But the value and unit of "k" given in the Wikipedia page is different. Do you know what NASA document means by "universal gravitational constant" in modern sense?


The code appears to use in some places GK2M, which is the Newtonian constant of gravity, and in other places SQRDK, which is inappropriately described as a "gravitational constant", but it actually is the mass of the Sun expressed in some special units.

Newton's constant is known only with a very high uncertainty, i.e. a very low precision.

For the great bodies of the Solar System, e.g. the Sun and the planets, one knows with a high accuracy the product between their mass and Newton's constant, because that can be measured by the force with which they attract a body of known mass, e.g. an artificial satellite or an interplanetary probe.

Computing their mass in kilograms would be pointless in most cases, because that would introduce great uncertainties in the computations. So for the Sun and the planets one expresses their masses by the products between their mass and Newton's constant, whenever that is possible, i.e. whenever one needs to compute their attraction force exerted upon a small object.

Wikipedia names the product mass-Newtonian constant as "the standard gravitational parameter of a body", but I believe that this is a misleading name, because this product is just the mass of the body expressed in different (non-SI) units. Expressing a mass by its product with the Newtonian constant is not different from expressing the mass in pounds instead of kilograms. Using the Newtonian constant instead of some random unit conversion factor just has the advantage of removing the uncertainties from some expressions computing forces of gravity.


It's just regular old G, defined in mass-of-sun units: https://en.m.wikipedia.org/wiki/Gravitational_constant (fourth item in the first table: NASA also uses meters whereas Wiki uses km)

Gauss's constant k is defined as sqrt(G), but for a while the international standard was to define k and then compute G as k^2, which is why NASA refers to it that way.


I think it's just units. From wikipedia: "and its value in radians per day follows by setting Earth's semi-major axis (the astronomical unit, au) to unity, k:(rad/d) = (GM)0.5·au−1.5."

the value given in the paper assumes the distance in meters I think.


Mathematician Norman Wildberger has been criticizing the embrace of infinitiy by modern mathematicians for decades: https://www.youtube.com/@njwildberger/search?query=infinity


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