We have been done a disservice by being supplied a link to the PDF, rather than the abstract https://arxiv.org/abs/gr-qc/9706055v1

The pdf version is somehow showing a date in 2021, although this is clearly a 1997 preprint. SemanticStrength's reply to you also implies this was written in the 90s. The PDF has the 1997 date on the clickable link back to the arxiv, so there is some time-travel going on that I do not understand.

The date of the preprint is important context, for reasons I'll return to at the end, wrt your point about the CMB.

> huge red flags

Are there? I'm not sure I agree.

> Single author

Common enough in theoretical physics. Just today : https://arxiv.org/list/gr-qc/new there are at least half a dozen.

> Not peer-reviewed

That's your parent comment's complaint, isn't it? I do not know if it was peer-reviewed. I don't expect the paper to gain much traction with anyone in 2022 since it advocates abandoning local Lorentz covariance (which is exceptionally well tested, directly, in our solar system), so I don't feel any desire to play Reviewer 2 today. I have a handful of comments below, though.

But cf. https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=Ilja... for this author, who has been published in this field.

> No affiliation

Hardly unknown in this field. Also hardly unknown for an instutionally employed author to omit an affiliation for unstated reasons (or even accidentally), which appears to be the case here. See also the later preprint's affiliation of Weisterstrass Institute, Berlin[1]. And, if there is any doubt, <https://archive.wias-berlin.de/receive/wias_mods_00000235>.

> Barely contains any math except for some basic equations

I'd love to meet the people who think §3 is basic stuff.

> known to undergrads

I spent more minutes than I care to admit hunting down p.14's "well known Lagrangian". In another preprint [1] the author gives a reference for it as Rosen, Ann. of Phys. vol. 22, nr. 1, pp. 1-11, 1963. Which, it turns out, corresponds to https://sci-hub.se/https://doi.org/10.1016/0003-4916(63)9029... at eqn (13), which the author has rewritten in modern notation.

Is this well-known? You decide: <https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=flat...>

I would say, at the very least, that it isn't something expected to be known by undergrads.

> Claims to trivially solve a huge problem on a few pages

Also hardly unknown in this field. Sometimes successful, even, although I think it's more common that short papers tend to reveal or create huge problems instead.

In the broadest sense the idea is not entirely insane for 1997. Starting with a continuum theory acting on a fixed background, then quantizing that into a QFT, is a frequently-used approach. Lattice QCD was all the rage, so "de-continuumizing" the resulting QFT doesn't strike me as particularly bad. Claiming results on a lattice hold up as we take the lattice spacing to zero was very 1990s.

Where things go off the rails is in §5: "The conclusion is very non-trivial: we have to choose this non-relativistic theory as the best available theory of quantum gravity. That means, the relativistic paradigm has to be rejected. Instead, we have to use pre-relativistic ether-theoretical metaphysics." That would have been an impossibly hard sell to a 1997 journal editor, just for tone. For reviewers, it is not clear they would agree this point is supported by the preceeding sections. For potential reviewers in 2022, the core approach itself and the other arguments raised in the Discussion section have been overtaken by other developments, notably in numerical relativity and numerical methods for quantum gravity.

However, the idea of a Galileo-invariant ether was not particulary insane (Jacobson & Mattingly 2000 <https://sci-hub.se/https://journals.aps.org/prd/abstract/10....> cf the preprint under discussion at Definition 1's second bullet; more broadly, <https://en.wikipedia.org/wiki/Einstein_aether_theory>). This also answers your

> why hasn't anyone thought of it

They have.

> why won't anyone recognize this paper?

I have no idea whether the author submitted it to a journal or not, or even planned to do so without further work. I don't think SemantincStrength or you knows either. However, it is not "the first valid cannonical quantization of Gravity" (as SemanticStrength wrote), by three decades. (Bergmann, 1966; DeWitt, 1967 -- DeWitt is what you find in textbooks and DeWitt is also what you find in [6] of the preprint SemanticStrength took us to).

> how do you explain the CMB? The fact that the author has not preemptively answered this crucial question already tells me this is not worth my time.

You took time anyway, as did I. I don't buy the novel arguments raised in the preprint, but I have twenty-five years of history accumulated since it was written. Speaking of since it was written, the first data from BOOMERanG was in 1997 with 2000 data being acutely relevant; MAXIMA wasn't until 1998, so even coarse knowledge about the anisotropies arguably postdates this 1997 preprint. I don't think you can lean on COBE's primary findings (or anything earlier) without further developing your objection. \Lambda-CDM was very new when the author was writing this preprint. It was not even the favoured model until the discovery of the accelerated expansion in 1998 (High-Z, SCP).

Finally, I think we have conflated SemanticStrength's comments with the content of the preprint, and perhaps only because the preprint is in numerous places rather forceful in tone.

- --

[1] https://arxiv.org/abs/gr-qc/0104013v1 (2001 but dated 2011) p.5, "There are Lagrangians which are not strong covariant but have covariant Euler-Lagrange equations, like the well known Rosen Lagrangian [20]. This is a consequence of the fact that the Lagrangian is not uniquely defined by its Euler-Lagrange equations. But the Rosen Lagrangian is a well known GR Lagrangian too." Emphasis mine. Also, O RLY.