Foundations of a theory of quantum gravity - Johan Noldus' book.

[MTd2]

http://arxiv.org/abs/1101.5113

Foundations of a theory of quantum gravity

Johan Noldus
(Submitted on 26 Jan 2011)
After a long technical and consequently philosophical disgression about the necessity of the construction presented in this book, a logically consistent and precise theory of quantum gravity is presented. The construction of this theory goes in several steps; at first we take a fairly conservative point of view and stumble upon some technical difficulties. Consequently, we investigate a new mathematical implication of an old idea to solve these problems; the latter suggest however a completely new way of doing quantum theory. This novel theory automatically incoorporates an extended form of gravity as well as a quantum gauge theory. We compute that the well known free quantum field theories and Newtonian gravity emerge in a suitable limit. The philosophy constructed here is to a high degree Whiteheadian.

*******

This paper/book was uploaded today. I put his name on google and saw that marcus put him on an observation list a few years ago:

https://www.physicsforums.com/showthread.php?t=102147

This thread was attended by Garrett Lisi, Thomas Larson and Careful. It seems that careful also keeps track of this author, as google point out his participation explaining Johan Noldus' ideas on other threads.

This is kind of a surprise to me. I thought that he, like Fra, didn't like anything...

 

[marcus]

We can help Noldus if each person will take a paragraph from the book and correct the spelling---he may also appreciate positive or negative comment (authors sometimes do like to get feedback on a draft) especially since the book is not yet finished. The conclusion section remains to be written. Here are some minor spelling corrections:

==quote page 156==
Only meaning resists definition, it transcends knowledge and all the rest; still it is the driving force behind our actions and the way we think about the world. Meaning, I believe, is an eternal self-reffering concept which catches words like: I, You, Survival, Food, Procreation, Love and so on ... which never ever change. Knowledge is a dynamic relational component between entities having a certain meaning; therefore it is only very basic in the sense that it only uses well defined words like (probably) implies, is (more or less) equivalent to and so on. The creation of new knowledge always involves an interplay between meaning and contemporary knowledge; therefore, by the lack of a definition of meaning, we will never ever be able to write down a theory of everything. Science will always be a game of humans running behind their own tale as well as a vital ingredient in changing our own future and the laws of the universe themselves; therefore the way things are will also change depending on the knowledge we have of it. There is however hope and the scientific enterprise is certainly not doomed; that is, I think it is fair to say that microscopic physics will satisfy the general principles we laid out in section eight. Surely, one may increase complexity in the gravitation theory by going over to higher bundles; this will necessarily change the way we think about quantum physics too meaning that the implementation of the principle of Lorentz covariance has to undergo some modifications. Likewise, we may further generalize quantum physics by allowing for nonassociative ”algebra’s” or by introducing some nonlocality by letting the product depend upon the number of factors. But that doesn’t imply we don’t understand microscopic phyisics, we do: we know the basic principles and all the rest is merely representation. Likewise, I have tried to formulate a principle for macroscopic physics; in contrast to the microscopic world, this does not allow for a well defined theory but we can produce well defined approximations. This is good enough and we better learn to live with this limitation. It is as if we are allowed to understand and grasp the linearization of a reality in which the nonlinear terms involve that what we cannot define: understanding.
==endquote==

"well defined" takes a hyphen when the noun modified immediately follows: well-defined theory

"phyisics" : physics

"self-reffering": self-referring

"tale" : tail

The idiom is "like a cat chasing its tail" or more generally the image of anything "chasing its own tail".

Hopefully the author will find this helpful, if he happens to see this thread.

 

[Careful]

http://arxiv.org/abs/1101.5113
This is kind of a surprise to me. I thought that he, like Fra, didn't like anything...

Well, people always make premature observations like that. If one is critical towards half-baked mainstream approaches, then they automatically presume you are inherently negative about everything.

 

[MTd2]

Probably you've read the paper, then. Would you mind explaining the central idea contained, very very roughly?

 

[Fra]

This is kind of a surprise to me. I thought that he, like Fra, didn't like anything...

For a change I agree with what Careful said :)

About the paper, my first impression is: it's long, and the first pages seems to contain very little selling points as to why I should keep reading. Skimming further I see parts I don't like but also some parts I do like.

> "But the unification of the ’state’ and ’action’ in a single measure is certainly a much
> better idea which is also capable of encapsulating topology change in quantum gravity."

Without having read this paper, this associates to something that is exactly what I've advocated in several threads, namely that the principle of maximum entropy and the principle of minimum action are really the one and the same principle, which unifies entropy and action. This is a key component in my own thinking as well.

My argument for this, is that one you take the intrinsic construction of a measure seriously, there is no way to artifically distinguishing information about states and information about motion, so states and states of motion must be unified. Specifically they are both information divergences. The only difference is if you consider "a priori probabilities" or transition probabilities (ie motion). If you look at the mathematics and an alternative foundations of probability theory based on "counting evidence", that I'm working on then max ent principle and principle of least action is in fact just ONE principle. Their unification is interesting. Since he mentiones this it motivates me to skim a little further to see how this is developed.

More later... when/if I get the time need to read it. I would prefer that he tries to write that paper from a more sales perspective. His first 5 pages should sell the rest of hte paper, because there is a decent chance that people stop reading and make premature judgement.

/Fredrik

 

[Careful]

For a change I agree with what Careful said :)

About the paper, my first impression is: it's long, and the first pages seems to contain very little selling points as to why I should keep reading. Skimming further I see parts I don't like but also some parts I do like.

More later... when/if I get the time need to read it. I would prefer that he tries to write that paper from a more sales perspective. His first 5 pages should sell the rest of hte paper, because there is a decent chance that people stop reading and make premature judgement.

/Fredrik

The introduction treats all major obstacles to quantum gravity so I don't understand why you say it would not ''sell the book''. Not liking something because it clearly doesn't work is fine, but not liking something because it conflicts your fine taste is a whole other thing.

 

[Fra]

The introduction treats all major obstacles to quantum gravity so I don't understand why you say it would not ''sell the book''. Not liking something because it clearly doesn't work is fine, but not liking something because it conflicts your fine taste is a whole other thing.

What I mean is that, it's an impression obvious from the title and the abstract that "this is a guy that might propose an original idea to the problem of quantum gravity quest".

But I've seen quite lot of such papers, and I don't have the time to read them all, even if I wanted to.

So what I expect in the introduction is something the seduce me to the point where I am inclined to this that this is more promising that all other papers, so that I will actually maybe even read all of it.

For example, the layout of a TEXTBOOK in say "the foundations of quantum mechanics" that is targeted for an audience that is taking a course, or trying to learn en established theory, is and should be different. It usually starts by lenghty definitions etc, introducing the mathematical framework. The payoff is usually in the end. That is I think fine if the reader is comitted to reading the book already - which is the case when you read a textbook for a course.

But my first impression is that this is yet another speculative idea... and I have no a priori reason to comit to reading it all like I would when deciding to read a textbook on say algebra.

Before I even read it, the author trying to push a new idea, need to convince the reader to actually keep on reading.

So my only opinon is that perhaps the early part (which people read first) should be more focused on declaring the unique sellings points of his approach, and why this paper is more likely to satisfy the reader than other papers.

But I haven't read it yet, so maybe it's great? I don't konw yet :) the bits I noted in skimming the intro above, is what motivates me... a lot of words like "free will" "god" and other things that appeared on skimming are more like warning bells to me. Maybe that's just the introduction though, but then it seems dangerous to put that in the beginning of the paper.

/Fredrik

 

[Careful]

What I mean is that, it's an impression obvious from the title and the abstract that "this is a guy that might propose an original idea to the problem of quantum gravity quest".

But I've seen quite lot of such papers, and I don't have the time to read them all, even if I wanted to.

For example, the layout of a TEXTBOOK in say "the foundations of quantum mechanics" that is targeted for an audience that is taking a course, or trying to learn en established theory, is and should be different. It usually starts by lenghty definitions etc, introducing the mathematical framework. The payoff is usually in the end. That is I think fine if the reader is comitted to reading the book already - which is the case when you read a textbook for a course.

But my first impression is that this is yet another speculative idea... and I have no a priori reason to comit to reading it all like I would when deciding to read a textbook on say algebra.

Before I even read it, the author trying to push a new idea, need to convince the reader to actually keep on reading.

I don't know from what planet you come but the author clearly states that a full, well defined, non perturbative formulation is presented and that some necessary consistency checks are presented in full detail. So again, I do not see your problem, perhaps you need flashlights and buzzwords, but I think the technical language is pretty clear for anybody who has mastered it.

 

[Fra]

I don't know from what planet you come but the author clearly states that a full, well defined, non perturbative formulation is presented and that some necessary consistency checks are presented in full detail. So again, I do not see your problem, perhaps you need flashlights and buzzwords, but I think the technical language is pretty clear for anybody who has mastered it.

If that's the motivation enough for you to sit down and actually go through and read 160 pages, sure.

I skimmed the first few pages, and I will try to skim more later. But for me to take my time to actually in depth, dedicatedly read and analyse 160 pages it better be damn good. Becuase I simply don't have that much time at hand. Because this is not the only 160 page paper I have to choose from.

I'm not sure if the author is supposedly famous or so, that would sell itself, but as an outsider heard of him before.

My point was supposed to be a constructive comment, in line with marcus initiation, that notes that in case he happens to read. But that's just MY impression. Perhaps most people are like you that will actually sit down and read the paper, but that sounds unlikely, no one has that kind of time at hand.

/Fredrik

 

[Careful]

If that's the motivation enough for you to sit down and actually go through and read 160 pages, sure.

I skimmed the first few pages, and I will try to skim more later. But for me to take my time to actually in depth, dedicatedly read and analyse 160 pages it better be damn good. Becuase I simply don't have that much time at hand. Because this is not the only 160 page paper I have to choose from.

I'm not sure if the author is supposedly famous or so, that would sell itself, but as an outsider heard of him before.

My point was supposed to be a constructive comment, in line with marcus initiation, that notes that in case he happens to read. But that's just MY impression. Perhaps most people are like you that will actually sit down and read the paper, but that sounds unlikely, no one has that kind of time at hand.

/Fredrik

I always love it when people standing on the shore know how to sail better than a qualified boatsman. If you know something about quantum gravity technically and not just philosophically, then you must understand that these claims are very unusual. Nobody so far had a good answer to Coleman-Mandula, Weinberg-Witten and Haag theorem... these are the cornerstones of quantum gravity.

 

[Fra]

I always love it when people standing on the shore know how to sail better than a qualified boatsman.

I never made such a claim.

I just make my own decisions where to invest my own time. There is nothing bold in that at all. I just tried to clarify that I just gave my first impression.

technically[/I] and not just philosophically, then you must understand that these claims are very unusual. Nobody so far had a good answer to Coleman-Mandula, Weinberg-Witten and Haag theorem... these are the cornerstones of quantum gravity.

So I take you have or will read the paper, then I'm interested to hear your brief analysis.

I can only speak for myself, and I don't know if we ask the same questions. Those theorems are formulated relative to a context that I question anyway. I have made a choice to try to rethink alot. QFT to start with is based on a continuum. IF you reconstruct the basic structure I surely am not skilled enough to just like that predict how these theorems sort of "scale" long with that. It will be complex fore sure, and I'm not even sure to what extent they apply.

I have a certain perspective, and whenever I see a paper I look for connections to my own projects. I assume everyone does.

But I would really appreciate if you (if you read the paper) can answer MTd2's question. Summarize their main constructing principles, and characterize the approach suggested.

That's what I would liket extract for a starter, but it will take time... time I need to decide to invest or not. I have plenty of really interesting other papers on the poset and causal set stuff I have saved for reading but I stumble on new papers at a rate higher than I can read the old ones.

Anyone that has read the paper and analysed it could share their picture.

/Fredrik

 

[Careful]

MTd2 got an answer to his question since he was bold enough to ask.

Careful

 

[Fra]

MTd2 got an answer to his question since he was bold enough to ask.

Careful

Your recent responses in some thread has made me curious as to what your own vision or preferred direction of research is? It would probably help me understand your responses better. Are you doing some research for a living/professionally or is it a hobby for you?

On one hand you seem to not be too happy about some mainstream work, on the other hand you also seem slightly disturbed about when other people object to the same. This makes me curious & confused as to what your own perspective is.

Edit: Found some old Careful-threads and found some clues.. I think I see some hints now :)

"the danger about philosophers in physics who actually cannot understand technical papers (and even have not some degree in the subject), is that they have the tendency to behave like high-priests in church."
-- Careful, https://www.physicsforums.com/showthread.php?t=115705&page=2

I am btw, not a philosopher, if that's part of the issue here.

but I still am curious to briefly see your own view (if it's already in past threads, referencing that is better).

/Fredrik

 

[Careful]

Your recent responses in some thread has made me curious as to what your own vision or preferred direction of research is? It would probably help me understand your responses better. Are you doing some research for a living/professionally or is it a hobby for you?

but I still am curious to briefly see your own view (if it's already in past threads, referencing that is better).

/Fredrik

I think I am done giving hints. If you are confused, ask MTd2, he was less so. For example, if you want to know more, why don't you contact the author ?

Careful

 

[Fra]

I think I am done giving hints. If you are confused, ask MTd2, he was less so. For example, if you want to know more, why don't you contact the author ?

Careful

You're certainly right about that. Sorry perhaps I was unclear, what I meant in the last question was YOUR views of QG. I don't mean your views of that paper, but your own take on the QG quest overall. I was curious to see where you are coming from. I was trying to understand the rational behind your comments.

What I mean is: Are you working on something original, not yet pubslihed, or are you working related to some of the major programs? Strings, LQG, causal sets, hidden variables etc? I haven't been able to get a coherent picture.

With some of the most active posters you easily acquire a picture of their way of reasoning. But with you I'm confused.

My own perspective I've declared throughout myposts here. This is a passionate hobby for me, not a job were I made a living. I also try to the extent I have time to work out some original ideas I have. Meanwhile there are some people to which ides I connect: Ariel caticha, some of Smolin/ungers evolving law, SOME of Rovellis RQM motivation (but not all), and I find some of the order methods of poset and causal sets to be interesting and underdeveloped as compared to the more pure algebraic methods. I also like some of the entropic reasoning ideas.

I'm curious where your perspective sits?

Edit: To stay ontopic, I'll get back with my personal impressions if I get around to keep skimming that paper.

Edit2: I've started to skim on, and it may prove interesting, but some formulations reminde me faintly of some of Carefuls past posts. Could it even be that Careful is the author? :)

/Fredrik

 

[Careful]

Edit2: I've started to skim on, and it may prove interesting, but some formulations reminde me faintly of some of Carefuls past posts. Could it even be that Careful is the author? :)

/Fredrik

Who knows ? :rofl: :rofl:

 

[Demystifier]

Let me just say that I agree with most objections and observations of Fra.

To convince others that one is right, it is not enough to be right. Not even in science. Sometimes less is more, especially when one wants to attract attention to a completely new idea.

Or to quote Einstein:
"If you can't explain it simply, you don't understand it well enough."

 

[Careful]

Let me just say that I agree with most objections and observations of Fra.

To convince others that one is right, it is not enough to be right. Not even in science. Sometimes less is more, especially when one wants to attract attention to a completely new idea.

Or to quote Einstein:
"If you can't explain it simply, you don't understand it well enough."

I told you a few times that you have to think 10 steps ahead instead of one. Just a thought ... imagine a guy who has been in relative solitude for some time, do you think he is in a hurry to promote his work with flashlights and bells ?

Careful

 

[MTd2]

Noldus' graviton is easy to get.

Shoot a lot of graviton lasers into a single point. No matter how many you shoot there, geometry won't bend. It will just bend if they meet matter. So, matter will bend geometry.

So, the sequence is not geometry <-> matter, but graviton(following geometry) <-matter->geometry

 

[Demystifier]

I told you a few times that you have to think 10 steps ahead instead of one.

Unfortunately, I don't have capacity to do that. (Perhaps 2 or 3, but not 10.) Nor most other physicists have, I'm afraid.

By the way, one famous chess player was asked how many moves he sees in advance. He replied:
- Only one, the right one!

 

[Careful]

.
By the way, one famous chess player was asked how many moves he sees in advance. He replied:
- Only one, the right one!

This is not necessarily in conflict with what I said

 

[unusualname]

Careful, you say on page 9 that "the dynamics of the specific proposal
however satisfies the third order interference rule" and reference this paper from 2008 http://pirsa.org/pdf/files/366ce8ad-908b-4a2e-9909-33d12070d25d.pdf .

But a more recent publication (by some of the same authors) claims to rule out (within quite good bounds) higher order interference Ruling Out Multi-Order Interference in Quantum Mechanics

 

[Careful]

Careful, you say on page 9

Good attempt !

But a more recent publication (by some of the same authors) claims to rule out (within quite good bounds) higher order interference Ruling Out Multi-Order Interference in Quantum Mechanics

Yes, but such terms are expected to be very small (and 10^{-2} is not a very small number) otherwise we would have seen it already for long time.

Careful

 

[unusualname]

Good attempt !


Yes, but such terms are expected to be very small (and 10^{-2} is not a very small number) otherwise we would have seen it already for long time.

Careful

Yes, I guess it's not the most compelling experimental evidence, since as you say, if the rule was violated above this bound (~1% of |psi|^2 interference terms) it would surely have been noticed elsewhere. I wonder why Science deemed it worthy of publication.

Noldus' paper/book has some interesting discussion at the start, but it comes across as very speculative and rambling, and may put off those with the required expertise from trying to follow the technical framework presented later on, especially since the arguments are long and hard. Some relevant experimental results would of course help, or a clear explanation of what specific problems this theory claims to solve.

 

[Careful]

and may put off those with the required expertise from trying to follow the technical framework presented later on, especially since the arguments are long and hard. Some relevant experimental results would of course help, or a clear explanation of what specific problems this theory claims to solve.

Nobody said it was going to be easy. Those with expertise go directly to the technical framework and read the rest only later on to understand things in a better way. What problems it claims to solve? It claims to be a consistent theory of quantum gravity, isn't that sufficient motivation anymore?

Perhaps these ideas are not speculative at all (but instead very deep realizations) and they find a natural place in the technical language developed later on. And rambling is always personal, I prefer ''direct style'', better than people who keep on talking and talking and in the end say nothing at all.

 

[qsa]

Nobody said it was going to be easy. Those with expertise go directly to the technical framework and read the rest only later on to understand things in a better way. What problems it claims to solve? It claims to be a consistent theory of quantum gravity, isn't that sufficient motivation anymore?

Perhaps these ideas are not speculative at all (but instead very deep realizations) and they find a natural place in the technical language developed later on. And rambling is always personal, I prefer ''direct style'', better than people who keep on talking and talking and in the end say nothing at all.

The author makes a commendable expose of the conceptual problems of QG in a very detailed and a useful way, but it seems to me that the theory is a variation of EC theory , although the author never mentions that in the references.

like this paper

http://arxiv.org/PS_cache/gr-qc/pdf/9309/9309027v1.pdf

 

[Careful]

but it seems to me that the theory is a variation of EC theory, although the author never mentions that in the references.

like this paper

http://arxiv.org/PS_cache/gr-qc/pdf/9309/9309027v1.pdf

Not at all ! It is far more complex than EC theory :-) The quantum theory is also far more advanced than standard QFT.

 

[atyy]

"Finally, I thank Wilhelm Furtwangler and Kirsten Flagstad for harmonizing my brain again when it got overloaded due to thinking too deeply."

 

[Careful]

"Finally, I thank Wilhelm Furtwangler and Kirsten Flagstad for harmonizing my brain again when it got overloaded due to thinking too deeply."

The guy obviously has a good taste for quality

 

[atyy]

 

[S.Daedalus]

There's a lot of philosophically non-trivial (and rather non-mainstream in as much as something like that exists in philosophy) stuff that is presented in a seemingly somewhat unmotivated manner (panpsychism, talk about 'mind-matter unity' etc.), some of which I am not sure if it is being used in a metaphorical manner (that the Everett interpretation necessitates some form of global consciousness for some reason or another), which I think serves mostly to obscure whatever points are being made. So that after reading (well, skimming) the first two chapters, I am still not entirely sure about what, exactly, the aims of the proposed theory are supposed to be (other than to present a 'consistent theory of quantum gravity', which is, of course, easily said), what its methods and constituents are, where it stands on the traditional interpretational and technical issues of QG, how it relates to/differs from other proposals, etc. In short, there hasn't been much of a hint of the payoff to be expected from continuing to slog through, other than a few rather vague promises.

I recognize that a revolutionary proposal -- which, for all I know, this still may be -- has to break with some traditions (otherwise, it would hardly be revolutionary), but if it does so that swiftly and completely as to be nigh-incomprehensible to those still mired in these traditions, without producing compelling reason for such a break, it can't hope to achieve its goals. If you want people to follow you, you should tell them where you're going (it's only common courtesy, after all)!

 

[Careful]

There's a lot of philosophically non-trivial (and rather non-mainstream in as much as something like that exists in philosophy) stuff that is presented in a seemingly somewhat unmotivated manner (panpsychism, talk about 'mind-matter unity' etc.), some of which I am not sure if it is being used in a metaphorical manner (that the Everett interpretation necessitates some form of global consciousness for some reason or another), which I think serves mostly to obscure whatever points are being made. So that after reading (well, skimming) the first two chapters, I am still not entirely sure about what, exactly, the aims of the proposed theory are supposed to be (other than to present a 'consistent theory of quantum gravity', which is, of course, easily said), what its methods and constituents are, where it stands on the traditional interpretational and technical issues of QG, how it relates to/differs from other proposals, etc. In short, there hasn't been much of a hint of the payoff to be expected from continuing to slog through, other than a few rather vague promises.

I think if you really understand the introduction, then you must realize how nontrivial it is. People just cannot read anymore in these days ... let me just pick a few sentences out which should ring bells ...

''My definition suggests an even wider generalization of QFT to non-associative structures we babtise to be kroups, as opposed to groupoids and semi-groups. The dynamics presented in section eight incoorporates the idea of a quantum manifold in which the unitary relators form a group locally, but only have a kroup structure globally.''

''The second idea consists in putting free quantum field theory on the tangent bundle instead of on spacetime itself''

''Indeed, as mentioned previously, our theory really has a local formulation and global considerations like hypersurfaces, action principles with ill defined integration over a noncompact spacetime definitively belong to the past. Of course, this implies that the probability interpretation is much more subtle too and considerable effort is made to clear this aspect out; for example the concept of a single state of the universe is wrong and we give a careful, new construction in section eight.''

Just to mention a few... these are very radical elements.

 

[Careful]

I didn't know that one, but it is pretty as always :tongue:

 

[S.Daedalus]

Just to mention a few... these are very radical elements.

They are, that's my point -- by and large (at least, as far as I could see upon a first read), such radical elements are just presented, without giving any reason for why they are needed -- without motivating them, that is.

As an example, according to conventional wisdom, there's not much of a need for non-associative structures in QFT (though the suggestion has been raised before). Of course, there are some problems with the 'conventional wisdom', and it's fine to break with it -- provided there's something to gain (that is not set off by any associated losses). It's just not all that clear to me (and there doesn't seem to be any specific effort made to clarify), coming for present purposes from a more conservative approach to QFT/QG, that there is anything to gain by considering 'kroups'.

 

[Careful]

They are, that's my point -- by and large (at least, as far as I could see upon a first read), such radical elements are just presented, without giving any reason for why they are needed -- without motivating them, that is.

The point is that the motivation for them is deep and the argument as to why they are necessary is spread out over 40 pages. But again, you ask the wrong question: you think someone needs to give a ''proof'' that these radical thoughts are necessary (which is given) but this is not really needed and certainly not how science functions. These ideas are very natural and they work, ordinary approaches don't. These ideas are thoroughly motivated from a very conservative point of view from section 5 onwards. But yes, you need to read for that.

For example, it would be possible to explain these ideas in say 30 pages in words, but then most people wouldn't get it you see. 99% of people who think right do it in a conservative way and at most 1% thinks natural. If you belong to the first class then you need to read a lot, if you happen to be in the second group you have the ability for shortcuts.

Careful