Hey Olaf,

Hope things are well!

I really enjoyed reading your essay, especially the simple model you use to get the MOND-like behaviour. Indeed, this model is a lot simpler than some of the other entropic gravity approaches. Very cute indeed! Flavio and I give a simple toy model, based on shape space, in our essay that gives a holographic behaviour. I wonder if there could be any connections between your particle models and shape space?

There is one thing that confuses me though. Can't the cosmological constant problem be stated without any reference to matter? If you just look at free gravity and use dimensional arguments then the cosmological constant should have dimensions of mass squared. But then the *dimensionless* cosmological constant has to be massively fine tuned to agree with the measured value. So the fine tuning problem is already in free gravity. Right?

Cheers,

Sean.

    Hi Sean:

    Thanks for the interest!

    I am going to have a look at your model. Very curious to see how you are getting the holographic behavior. In connection with that there is a question that I always wanted to ask you: Do you know this paper by Milgrom?

    The Mond Limit from Spacetime Scale Invariance

    The Astrophysical Journal vol. 698 (2) pp. 1630

    Is there a connection between your work on gravity and this? I am asking because both of you stress scale invariance. Have you looked at that?

    Your statement about the cosmological constant is correct. In an effective quantum field theory view of gravity your argument leads to a problem without the introduction of matter. A problem I have with that view is that you have to rely on a theory (pert. quantum gravity) that we know has problems. In the argument involving matter the only thing you need to know about gravity is that it reacts to the presence of energy. You don't even need to know anything about quantum gravity.

    It is also true of course that the cosmological constant problem without matter does not make the cosmological constant problem with matter go away. If you think of matter as sitting on spacetime the problem is there.

    Now on to your essay ...

    Cheers

    Olaf

    Hi Olaf,

    I know about Milgrom's result but I have not seriously looked at the consequences for SD. I had one crazy idea recently (if you'll allow me to indulge ;-). The conformal group in 3d is SO(4,1), which is the isometry group for de Sitter. Thus, I think a natural action for SD is the one of Stelle and West that uses an SO(4,1) connection because it can be decomposed into a conformal geometry in 3d.

    Now, how do you couple fermions to this action? You can't use normal spinors because the space is locally de Sitter NOT locally Minkowski. Thus, you shouldn't use spin 1/2 reps of the Poincarre group but rather spin 1/2 reps of the de Sitter group (which, is isomorphic to the conformal group). But, because the cosmological constant is small, these "dS spinors" should be effectively the same as standard spinors, at least for particle physics experiments. You would only notice a difference in the dynamics at cosmological scales related to the cosmological constant (because this is what distinguishes the dS group from Poincare). But the MOND scale is the cosmological scale! So maybe you would expect MOND like behavior from the SO(4,1) spinors?? And maybe the relation to scale invariance is because of the isomorphism with the conformal group??

    I don't know... but I'd like to look into this at some point! Did that make sense??

    I take you're point about the cosmological constant problem. You're right that the story might change once we have a good theory of quantum gravity. Now I understand your point. Thanks!

    Cheers,

    Sean.

    4 days later
    • [deleted]

    Dear Olaf,

    It has a while since I heard anything new about you. While I admit I liked your older work more still good to see you back. I hope you check out what I have done maybe it will give you an idea. Sorry for doing copy and paste from my other posts but it should be enough to give you an idea.

    In my theory everything is emergent all from a mathematical structure that describes random numbers and imperative relations between them. Interpreting the random numbers as line lengths, the relations between these lines generate all of the laws of physics. You get a beautiful unified picture of space (its points are the crossing of the lines-dynamic-), time(change of state-does not actually exist-), mass, charge, and energy.The theory is called "Quantum Statistical Automata".

    It is a kind of an automata conjectured by Wolfram and Conway, but mine derived from a more fundamental idea of why reality had to come about. Of course Dr Tegmark is also a believer in the mathematical universe. I did not know any of these great people back then, but I came to believe that reality is nothing but a mathematical structure and went directly to the simplest system to implement such program. I hit on the right system in no time due to a combination of a flash of brilliance (which we all experience), my engineering/problem solving background and extraordinary luck.

    From the following results it can be seen that the system shows how ordinary physics results arise plus some results that standard physics can only dream of. But the most important conclusion is that the system points to the REAL final theory. All is needed is some smart people to take it seriously, or wait for me to finish it up in due time. Of course the former will be much quicker than the later.

    Fundamental Theory of Reality,"Reality is nothing but a mathematical structure, literally".

    1. How I arrived at the idea.

    2. Basic results that shows how QM arises, written in BASIC program.

    3. Description of two particles interacting and explaining the program in C++.

    4. Showing the results for Bohr atom hydrogen 1s simulation.

    5. 1/r law and the running phase

    6. The amazing formulas deduced from the system.

    7. How spin arises from 2D simulation.

    8. The appearance of the mass of the electron through simulation.

    WORLD'S First, I am not Kidding.( it won't hurt to chuckle though)

    9. How gravity arises.(basic simulations not shown yet)

    There are many other results not shown.Attachment #1: 5_newqsa.pdf

    Hi Sean:

    I like the idea! I will have a closer look. I guess the meat lies in the transition

    SO(4,1) --- \Lambda ->0 ---> SO(3,1)

    How do the spinors change?

    More later ...

    Cheers

    Olaf

    After studying about 250 essays in this contest, I realize now, how can I assess the level of each submitted work. Accordingly, I rated some essays, including yours.

    Cood luck.

    Sergey Fedosin

    Dear Sergey:

    You read 250 essay! That is very impressive.

    Thank you for the consideration and the vote.

    Cheers

    Olaf

    • [deleted]

    Dear Olaf

    Don't forget please impartially evaluate my essay

    • [deleted]

    Dr. Dreyer,

    Hi. As with many of the more mathematical essays here, I can't say I understood all of your paper because I'm a biochemist and not a physicist or mathematician, but I can say that based on my own thinking, what you're saying makes a lot of sense, and I will give you a high rating with my vote. I would further add that just about everything, including matter and energy and everything else, is an excitation of, or emergent from, a background. My reasoning would be something like:

    1. In thinking about the question "Why is there something rather than nothing?", I've come to the conclusion that there is a fundamental existent state, and it doesn't matter if this state is called matter, energy, something, nothing, quantum fluctuation, mathematical construct, causal set, etc.

    2. Because our universe has more than one existent state in it, this initial state must have had some way of replicating itself to create more states, which would then be able to create yet more states, thus leading to a big bang-like expansion of space and volume that we call the universe. Thus, our universe, our existence, is made of an expanding sea, or set, of existent states.

    3. Because we have movement in our universe, there must have been some mechanism for allowing these existent states to change and transfer this change to adjacent states, in the form of energy. Since we're talking about the physical universe, the existent states would have to be three-dimensional states, and the most basic way I can think of for a 3D existent state to change would be a change, or deformation, in its shape which it can somehow transfer to adjacent states.

    4. Because our universe is made of these existent states, everything we see around us, must be excitations within, or of, these states.

    To postulate that in addition to the fundamental existent state there is something (e.g., matter) totally different that's "sitting on", as you mentioned, this sea of states, doesn't make much sense. If we really want a unified theory of everything, it makes sense to me that there would be excitations within a sea, or set, of replicas of the fundamental existent state. You can't get much more unified than that, I don't think.

    If you're interested, my model for how the above might happen based on proposed solutions to the questions of "Why do things exist?" and "Why is there something rather than nothing?" was the subject of my last FQXi essay from the last contest and is at my website at:

    https://sites.google.com/site/ralphthewebsite/filecabinet/why-things-exist-something-nothing

    You could also try the main site at https://sites.google.com/site/ralphthewebsite

    and click on the third link.

    Anyways, from this amateur's viewpoint, good essay, and good luck!

    Roger Granet

      If you do not understand why your rating dropped down. As I found ratings in the contest are calculated in the next way. Suppose your rating is [math]R_1 [/math] and [math]N_1 [/math] was the quantity of people which gave you ratings. Then you have [math]S_1=R_1 N_1 [/math] of points. After it anyone give you [math]dS [/math] of points so you have [math]S_2=S_1+ dS [/math] of points and [math]N_2=N_1+1 [/math] is the common quantity of the people which gave you ratings. At the same time you will have [math]S_2=R_2 N_2 [/math] of points. From here, if you want to be R2 > R1 there must be: [math]S_2/ N_2>S_1/ N_1 [/math] or [math] (S_1+ dS) / (N_1+1) >S_1/ N_1 [/math] or [math] dS >S_1/ N_1 =R_1[/math] In other words if you want to increase rating of anyone you must give him more points [math]dS [/math] then the participant`s rating [math]R_1 [/math] was at the moment you rated him. From here it is seen that in the contest are special rules for ratings. And from here there are misunderstanding of some participants what is happened with their ratings. Moreover since community ratings are hided some participants do not sure how increase ratings of others and gives them maximum 10 points. But in the case the scale from 1 to 10 of points do not work, and some essays are overestimated and some essays are drop down. In my opinion it is a bad problem with this Contest rating process. I hope the FQXI community will change the rating process.

      Sergey Fedosin

      Hi Olaf,

      Glad you're interested. There might be a clue to how to do this in Hans Westman and Tom Zlosnik's new preprint. But they seem to look at what I'm suggesting but they find no change from Dirac-GR. Apparently there are some terms that cancel. In any case, I would like to understand this better. Maybe there is a way to get something like the MOND behaviour.

      Anyway, take care and good luck in the competition!

      Sean.

      • [deleted]

      Sergey G Fedosin is bombing entrants' boards with the same "why your rating has dropped" message. They are all dated Oct. 4... same message.

      WTH? I've seen one fine essay drop 89 (eighty-nine) positions, in "Community Rating" in the past 24 hours, and "Sergey's note" came BEFORE it plummeted. Hmm.

      The vote/scaling of this contest is quite nebulous.

      "Hackers Rule!", I suppose!

      Well??? What else is one to think? The General Public is... Watching...

      Olaf

      Roger Granet brought my attention to your essay, so here are some comments on it:

      "Particles are either fundamental or they are emergent. If they are fundamental they are sitting on a background; if they are emergent they are excitations of a background"

      Physical existence (as known to us, which is all there is unless one enters the domain of belief) must comprise elementary substances, ie that which has a detectable (indirectly or directly) physical presence but is not further divisible physically. Otherwise physical existence could not occur. There are probably different types of elementary substances. But the substance of physical existence must not be confused with reality, ie what is physically existent at any given point in time. That cannot be substance, per se. Because physical existence not only occurs (ie has substance), it alters. And by definition, any given elementary substance does not alter, it is physically indivisible. So a physically existent state (a reality) is associated with a specific condition of the elementary substances (and indeed a specific configuration vis a vis other elementary substances).

      Another way of looking at this is to ask what is 'matter' as opposed to 'background'. Both imply a physical presence, just a different type thereof. Which then invokes the questions: a) physically what is 'background', b) physically what constitutes 'sitting'. Then when looking at the alternative proposition, the questions become: a) physically what is 'excitation', b) again, physically what is 'background'. Also I do not understand what the concept of 'emergent' physically relates to. Either something has physical presence or it does not. And nothing can be deemed to have some form of physical influence but then denied a form of physical presence. Then either, in terms of physical substance, that something is fundamental or it is not. Physical existence occurs independently of the processes which detect it and thereby render knowledge of it available.

      I suspect that:

      -'particles are fundamental' equates to: the substance of physical existence comprises...

      and

      -'particles are excitation of a background' equates to: any given physically existent state of physical existence is associated with....

      Paul

      Dear Roger & Paul:

      Many thanks for the interest in my essay!

      Let me try to give an answer to your questions. I think there is an important point to be made here that concerns the notion of emergence. To make thing clear let me start with an example: an ice cube. The frozen ice consists of water molecules that are arrayed in a very regular lattice. This lattice can vibrate and because we are dealing with a quantum system there exists a smallest unit for each of the vibrational modes. These are the phonons. In this example it is clear that the water molecules are more fundamental than the phonons. The phonons are just quantized vibrational modes of the lattice of water molecules.

      But now imagine how this situation would look to an observer made up from these phonons (this is a bit of a stretch because phonons are too simple to make up an observer but there are more interesting models of this kind that can do this). This observer would consider these phonons as the elementary particles of her world. The phonons would be like the light in our world.

      What I am proposing is that our elementary particles (electrons, quarks, light, etc.) are of this kind: they are the excitations of an unknown substance just like phonons are the excitations of the lattice of water molecules.

      Paul makes the statement:

      "Either something has physical presence or it does not."

      Here we have an example that doesn't quite fit into this dichotomy. The phonons have existence but if you melt the ice cube the lattice disappears and with it the phonons.

      I hope this helps.

      Cheers

      Olaf

      • [deleted]

      Olaf

      Thanks for your reply, it is good to come across someone who responds with a constructive statement, rather than, in effect, no it is not. Now I must just stress that I have no background, so I can only address the topic in terms of generic logic.

      So, starting with a sentence towards the end of the post: "The phonons have existence but if you melt the ice cube the lattice disappears and with it the phonons". Leaving aside the actuality of this, you have said that they did have a physical presence, but do not any longer. Having physical presence does not necessitate always having physical presence. This is the point, the difference between the indivisible/ inalienable substance of physical existence (of which there might be different types) and its physically existent state. What that indicates to me if that these phonons are an effect/state of the properties/whatever is the correct phrase, of something that does have permanent substance. Hence my phrase: "Either something has physical presence or it does not", still holds.

      This might not be the best expression, but it was a reaction to some who argued against my 'there must only be one physically existent state at a time' point by alluding to physical phenomena which somehow could have physical influence but no form of physical presence, and hence were not subject to the 'one at a time' rule.

      From this response I take it that 'emergence' refers to a type of physical existence which is not always extant? In crude terms, differentiating what is 'substance' from what is 'effect'. And your hypothesis that what we currently deem to be the substance is actually effect, seems viable. Of course it does still leave the question as to what is the substance! But your notion that it is something, as yet, unknown, is not quite as far fetched as some might think, ie how come after all this time we have managed to miss this(!).

      Because, and this is something else I keep on pointing out, our detection of reality is dependent on the sensory systems (we can hypothesise further on that basis, but without entering the realms of belief). But, apart from the more obvious mechanical issues with these processes, what somehow often seems to be forgotten is that what is received by the sensory systems is not what is being referred to as reality. It is physically existent phenomena which are caused by an interaction with other physically existent phenomena (which is what really is being referred to as reality). In the context of the sensory processes, the physically existent phenomena received are, in effect, representations of reality. But there can be no assumption, until proven otherwise, that these phenomena, which were just utilised in the evolution of sensory systems, do represent what existed either completely accurately and/or comprehensively (leaving aside all the issues of possible distortion en route and our inability to capture/process all that was available). You allude to something like this in the third paragraph, existence must not be confused with knowledge of existence. Existence occurs independently of the sensory systems. No form of sensing can have any effect on existence. It is just that knowledge of reality is only rendered available via these systems. We are part of reality, and cannot transcend it, therefore we can only know of it.

      Paul

      Dear Paul:

      I think I agree with what you are saying.

      May attitude about the question of what the substance is was always one of limited urgency. I was always more interested in investigating what the consequences of the presence of such a substance would be. One can for example investigate what the observable remnants of the process of emergence are. This could give rise to an alternative understanding of the big bang.

      Lots of stuff to do ...

      Cheers

      Olaf

      14 days later

      Dear Olaf Dreyer,

      In Coherently-cyclic cluster-matter paradigm of universe, the Galaxy rotation problem described with MOND is expressional differently by eigen-rotational string quanta of galaxies in the holarchy of universe, in that gravity emerges as a tensor product of eigen-rotational strings.

      In this paradigm angular acceleration of each eigen-rotational string is analogue of emergent excitations, whereas its inertial angular velocity is fundamental and thus the segmental dynamics of the universe in homeomorphism is expressional as the background of the universe.

      With best wishes

      Jayakar

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