Recently I happened upon a clickbait title on a website I respect; it was a story about a paper that had reaffirmed some of general relativity claims. As I had read the paper I wanted to read the comment section to learn more.
In what has to be one of the biggest coincidences ever, one of the commentators not only shared arguments that I have put forward on this site before, but whom also shares the same writing learning disability as I.
Unlike me, the poster appears to have made it further in the education system, and can also remember how to read FORTRAN and it willing to touch it. I personally refused to even look at fortran after 1995.
Anyway the poster obviously is also a better researcher too, because I always bought the claim that only Newtonian Mechanics was required for even space missions to other planets.
But apparently Every inter-planet mission post Mariner VI uses relativistic corrections, and without the “Double Precision Orbit Determination System” which has been in use from 1970 voyager couldn’t have even gone on the grand tour.
I always figured that the issue was with me as I saw the issues with the moons movement and Newtons weird adjustments to the inverse square law etc…
I figured I just didn’t know how to account for those errors due to my own limitations, as almost everyone claims that GR isn’t needed unless your path approaches the sun.
My own, admittedly limited math skills couldn’t ever figure it out.
Note, I am not anti-Newton, and actually personally believe that he is one of the smartest humans to ever walk the earth.
But it appears that you don’t have to consider relativity for attitude control if your are not near the sun, but absolutely have to consider it for Doppler range finding that is a critical for telemetry.
But even more, the ephemera produced by JPL, has used and has required relativistic corrections for 45 years, and in fact the errors in Newtonian mechanics resulted in the IAU moving to a post-Newtonian model which they started in 1991 and completed in 2001.
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So in part I am also pitting myself for not googling more, but I as I have little experience in orbital mechanics I also pit the dopers who claimed more experience but were obviously cargo-culting common physics legends.
Sure if you chose a special case like a spherical orbit of limited duration around the earth and don’t have to consider rendezvous or optimize payloads you can probably ignore the effects. but if you need to have orbit locations accurate within fractions of a KM vs being OK with dozens of KM of error you have to.
As the JPL ephemera have been making these corrections a siloed NASA engineer may not have been exposed to the relativistic corrections if they ignored the readme but to claim that any significant missions were accomplished with just Newtonian physics is like claiming that you don’t need a compass and a map or cartographers because you have Siri.
While it is best practices to use the simplest method for solving any problem, those of you who still claim that relativity isn’t practical or needed, or those of you who claim that Newtons mechanics are just as valid for our use cases…you are the spacetime equivalent of a flat-earther!!!
And for those who have erroneously claimed that Newtonian approximations model the current best understandings of fundamental physical properties I doubly pit thee!!!
A thrown tossed basketball is falling a consent speed straight line and the IIS is going at a consent speed straight line. You can stick to your superseded, redundant claims that weight and inertial mass are different to protect your short form F=ma, which is useful and short but if he was still alive even Newton himself would accept that you are in an accelerated frame and that form isn’t valid as a description of the fundamental reality of the world.
While useful, Newtonian mechanics are approximations, so quit using your ancient theories to beat down people who are actually trying to move past those outdated concepts.
There is a very good reason that even with the simplified but relativistic corrected post-newtonian methods are always appended with the term “approximation”
I don’t expect even a small percentage will ever make the effort to understand GR, but the anti-science, cargo-culting dogma surrounding these methods needs to stop.
