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Some answers might be found here, https://www.cpt.univ-mrs.fr/~rovelli/IntroductionLQG.pdf

There seem good reasons for scepticism regarding explanations relying on ignorance but there could be alternatives for coarse-graining that lack such problems, eg the paper linked post #15 https://www.physicsforums.com/threads/is-there-a-generalized-second-law-of-thermodynamics.1015122/

There was an interesting debate held on that sort of topic recently but I think it is behind a paywall, “Is the universe fundamentally predictable or unpredictable? Does the degree to which the future remains unknown reflect our own cognitive limitations, or the fundamentally open structure of...

Further, as an inference was drawn (in some alternative case), this paper considers possible such inferences (although this may not apply in the alternative case), https://arxiv.org/abs/1910.02474 Neither Presentism nor Eternalism Carlo Rovelli

I came across a more recent paper that might update some finer details - “Information is Physical: Cross-Perspective Links in Relational Quantum Mechanics“ https://arxiv.org/pdf/2203.13342.pdf

this paper discusses a view that has been said to be “local and realistic” https://arxiv.org/pdf/1806.08150.pdf

if I understand it, examples of stable facts can be systems that may be manipulated and measured macroscopically.

This detailed account looks relevant - https://quantum-journal.org/papers/q-2021-08-09-520/ The arrow of time in operational formulations of quantum theory “The operational formulations of quantum theory are drastically time oriented. However, to the best of our knowledge, microscopic physics...

From this is it your suggestion here that the laws-themselves do count relationally?

Perhaps this could help, especially the questions and answers at the end

Firstly, on one of the topics discussed, haven’t read it, but among the references is one this account - https://arxiv.org/abs/2010.13480. A second thought is that there is no reference to any qbist takes that could reqire notions of knowledge or subjectivity but rather information theory in...

On this, I just wonder what is meant by this, because hadn’t Born already named “Quantum Mechanics” for the discontinuous nature and written about probabilities and such, all before Schrödinger came up with a different easier approach, e.g. Born, Jordan, Z. Phys.33, 479-505, 1925; rec. 11-06-1925 ?

My impression is the trivial nature involves a strawman case where the literature’s relevant physical concepts weren’t addressed, and again, it concerned an older path 18 years ago, but the youtube debate between experts in strings and loops above, however, is just weeks old.

This, from last month, is far more up to date. (I also noted in the comments skydivephil mentions having been less active at physics forums recently)

Even though ways that that older pathway in LQG took back in 2004 are less interesting to me, perhaps this paper could also be mentioned https://arxiv.org/abs/hep-th/0608210 …”calculation in a recent paper by Helling et al [hep-th/0409182] are physically incorrect”.

I’d been thinking of issues generally that along with possible narrowing of alternatives discussed in the OP source there is breadth of other possible directions and emphases towards open questions, and those raised may be examples of, but replying has been problematic and on second thoughts I...

Nice introduction to Hermann, Jarvis, a fascinating person whose accomplishments include studying mathematics under Emmy Noether, exchanges with Heisenberg and this- ...” in 1935, Hermann published a critique of John von Neumann's 1932 proof which was widely claimed to show that a hidden...

Yes, I think I’ve previously linked e.g. a Lorentzian description in LQC somewhere in a thread here. There are varied alternatives and some crossovers and a description of Freidel’s recent work in a talk might interest Introduction to local holography - Laurent Freidel - Bing video . The tests...

I think the talk gave some developments and references, including those external to the theory like the BMV tests Witness gravity’s quantum side in the lab | Nature Phys. Rev. Lett. 119, 240401 (2017) - Spin Entanglement Witness for Quantum Gravity (aps.org) Also concerning testing, this is a...

Thank you, those references also seem quite old and might not account for some recent developments. This talk from a few years ago seems to expand on some of the issues in the OP paper in the first hour, although I could have a bad link that doesn’t let me watch all of it- hope it works ok here...

Was a reference provided specific to Rovelli when this was raised earlier in this thread?

Just concerning the thread topic, with BMV tests evidential support for quantum gravity or not could soon be within observational reach.

That is helpful, thanks very much.

Does Kent claim DH probability is ontic, and is that mistaken? Anyway, I don’t think that claim was made in the paper I linked, e.g. …“The beauty of the histories interpretations is the fact that the prob[1]ability of a sequence of events in a consistent family of sequences does not depends on...

I’m sorry, I don’t know Kent’s argument, would you tell me what it is please?

Differently perhaps, RQM is said to be more easily followed with gravity having already learned LQC and LQG. But similarly, although published earlier than the DH links provided, I think the paper linked in post 88 in some ways explains a possible extension of interpretations like DH concerning...

This helps a lot, thank you

From the Gell-Mann, 2011 paper you linked on page 5, section III, “Settleable bets, records, and decoherence”, there is a discussion of (some?) systems that might include frogs, ...”Information gathering and utilizing systems (IGUSes) like ourselves exploit the regularities summa- rized by...

I think there seems to be the suggestion of a special status for some systems among other systems and I prefer interpretations concerned with maintaining equivalence of all systems. If so, regarding IGUS, is there a definition that answers questions like whether a system’s status is subject to...

RQM involves relative states. This is an early paper, there could be further developments since, https://link.springer.com/article/10.1007/BF02302261 Published: August 1996 Relational quantum mechanics Carlo Rovelli International Journal of Theoretical Physics volume 35, pages1637–1678 (1996)...

Did you mean Bronstein, 1935, eg https://www.quantamagazine.org/physicists-find-a-way-to-see-the-grin-of-quantum-gravity-20180306/ ?

I think RQM’s ‘anti-realist’ reference is itself also arguably axiomatically ontic.

For a relational interpretation, this is an early treatment https://arxiv.org/pdf/quant-ph/9609002.pdf but I think there has been development since. In comparisons between different approaches in different areas of physics, the OP touched on frames of reference and some possibly implicit...

This paper linked elsewhere might be helpful here, https://www.nature.com/articles/s41567-020-0990-x Nat. phys 2020 A strong no-go theorem on the Wigner’s friend paradox Abstract Does quantum theory apply at all scales, including that of observers? A resurgence of interest in the long-standing...

A fresher foundational look at an old link from btsm might add some thoughts around the topic [gr-qc/0306059] A simple background-independent hamiltonian quantum model (arxiv.org)

I'll add the strong no-go theorem here that was mentioned in the earlier paper linked (Di Biagio, A., Rovelli, C. Stable Facts, Relative Facts. Found Phys 51, 30 (2021). https://doi.org/10.1007/s10701-021-00429-w, “Relative facts, stable facts”), and is in the following paper-...

This is a different paper than the one I posted before. It is about time with operational formulations. It doesn’t mention DH by name but does discuss some views and might be interesting here- The arrow of time ewline in operational formulations of quantum theory (arxiv.org)

Yes, I think in a context in which the conditions are met, Wigner and Friend agree. I think rather than requirement for complete decoherence, an approximate nature is described e.g., “ These observations show that decoherence does not imply that there is a perfectly classical world of absolute...

You're welcome. Given all the conditions and so on, like that decoherence is relative to a system, that a fact relative to F can become true for W, without W interacting with F, or subtleties such as allowing for "another system W′ that couples differently to these systems might still be able to...

This paper might help, e.g. subheading “Measurements”- https://link.springer.com/article/10.1007%2Fs10701-021-00429-w

Yes, it just occurred to me to edit to correct myself, thank you, I was referring to the discussion of the arrow of time from the earlier DH paper linked, and how different views might discuss the formalism, but I won’t edit for continuity.

(Another alternative could be considering just what is relevant…) The results of this could be interesting- Frontiers | On the Possibility of Experimental Detection of the Discreteness of Time | Physics (frontiersin.org) . I think CH treats time differently, as I think other views can treat it...

I don’t see any improvement on the article that has already been addressed.

thanks, I think that article is unhelpful and admits their argument does not agree with RQM primary literature and acknowledges succumbing to the temptation of entertaining such position anyway. The article, however, does refer to a recent paper that does seem helpful for a thread about RQM...

? Is there anything aside from the abstract? I get, “Our automated source to PDF conversion system has failed to produce PDF for the paper: 2107.00670.”

I haven’t read the book yet but the paper linked earlier discusses suppression of interference, e.g., “Various characterisations of a classical or semiclassical situation can be found in the literature: large quantum numbers, semiclassical wavepackets or coherent states, macroscopic systems...

This recent paper could help with your questions Di Biagio, A., Rovelli, C. Stable Facts, Relative Facts. Found Phys 51, 30 (2021). https://doi.org/10.1007/s10701-021-00429-w Abstract Facts happen at every interaction, but they are not absolute: they are relative to the systems involved in...

“The distinction between relative and stable facts resolves the difficulties pointed out by the no-go theorem of Frauchiger and Renner, and is consistent with the experimental violation of the Local Friendliness inequalities of Bong et al..” Published: 27 February 2021 Stable Facts, Relative...