Only read the first few pages, but as a non-physicist, but who went through grad school, it appears the author is advertising their own prior work quite a bit. I generally associate this behavior with a) cranks b) stubborn people who lost an ideological turf battle
I'm not a physicist, but a massive Wikipedia article on Alpha Centauri says nothing about the system not being gravitationally bound, and at least one scholarly article says they <i>are</i> gravitationally bound:<p><a href="https://www.aanda.org/articles/aa/abs/2017/02/aa29930-16/aa29930-16.html" rel="nofollow">https://www.aanda.org/articles/aa/abs/2017/02/aa29930-16/aa2...</a><p>> ... the question as to whether they actually form a single gravitationally bound triple system has been open since the discovery of Proxima one century ago. Owing to HARPS high-precision absolute radial velocity measurements and the recent revision of the parameters of the α Cen pair, we show that Proxima and α Cen are gravitationally bound with a high degree of confidence. The orbital period of Proxima is ≈ 550 000 yr.
> the fast orbit of Proxima implies it is gravitationally unbound given the visible mass of A and B<p>Since when? For example these measurements from 2016 say the opposite: <a href="https://www.aanda.org/articles/aa/full_html/2017/02/aa29930-16/aa29930-16.html" rel="nofollow">https://www.aanda.org/articles/aa/full_html/2017/02/aa29930-...</a>
I wish he spent a bit more time on the section regarding magnitude of the effect for different accelerations.<p>If indeed there is a minimum acceleration I wonder if it might not be measurable with some atomic physics experiment (atomic clock, etc..) in space a bit away from earth.
Really interesting paper, however:<p>>The Alpha Centauri system is ideal for testing quantised inertia since it is close
to us and well-observed.<p>Yet they're using 1994 estimate for AB mass, have nobody measured alpha centaury AB mass since 1994?
> All three stars are co-moving with similar chemistry, which implies they are bound<p>This is a weak assumption IMO. It is also possible that the stars "just" have a common origin and move at similar enough trajectories without being gravitationally bound.
Not a physicist, but I never heard of this before and looks quite interesting at first glance.<p>Google indicates that mainstream physics regards it sceptically ("pseudoscience"), but it was difficult for me to find out <i>why</i>.<p>I found a single paper containing criticism from an actual physicist ("A sceptical analysis of quantized inertia" by Michele Renda: <a href="https://academic.oup.com/mnras/article/489/1/881/5545603" rel="nofollow">https://academic.oup.com/mnras/article/489/1/881/5545603</a>), but that did not make the theory sound <i>that</i> bad, and it even mentions "absence of arbitrary tunable parameters", which sounds very promising to me...<p>I'd be very curious on why this is so controversial from an actual physicist (e.g. compared to MoND). Hopefully Hossenfelder will cover this at some point on youtube, those videos are always quite merciless with overhyped results...
> All three stars are co-moving with similar chemistry, which implies they are bound ...<p>I am not an orbital mechanic, but the word "chemistry" is jarring to me here. Is it just a strained metaphor or is there some sense it which it fits? Maybe the romantic chemistry of mutually attracting bodies?
So, not a physicist, but the claims in the PDF about how GR has "never predicted a single galaxy rotation curve" are overblown, right? Aren't there a handful of galaxies where the rotation curve lines up pretty close with the predictions from the visible mass? Any new physics has to explain those, too.<p>Anyway, I think I can see why QI is so appealing. The paper contains a very short and sweet explanation.