A Fundamental Space-Time Geometry: Does It Exist? by P. Aguilar, Y. Bonder, C. Chryssomalakos, and D. Sudarsky

Hi聽

Your 聽noteworthy contribution to this contest underlines the global goal to reconcile the gravitational and electric-charge phenomena under a common quantum theory.

Have you ever given thought that the gravity and electric-charge 聽attraction underly a common phenomena? This I propose in my essay, if that thought can be befriended the development of a common quantum theory may be easier.

To P.A.: As a student you may want to explain or comment the paradox of section 2.3 in my essay Rethinking Geometry and Experience

Regards

Anton

Yuri,

An admirable attempt to bring to life some of the serious obstacles confronting the development of a quantum theory of Gravity.

I hasten to agree that any attempt to develop such a theory from the current framework of Gravitation [ie Newtonian & GR] faces some serious difficulties most notably: No definition and distinction between mass & Matter.

I would suggest that a bottom-up approach is better suited to achieving the goal of a quantum theory of Gravitation, which is what I have done in Tetryonics [see attached SM particle models].

The strict geometrics of equilateral energies in Tetryonics provides a foundational geometry for the Energy-Space-Time interactions of all fields of Force along with a clear, enforceable distinction between interactive EM masses and gravitational Matter. Revealing nett Gravitation to be the result of 3 quantum field interactions [see attached] as Anton has alluded to in his comment.

I look forward to your comments on this approach to QG [and perhaps a review of my own essay].Attachment #1: 2_Figure_10.07__Tetryonic_Charge_Geometries_800x600.jpgAttachment #2: Figure_69.03__Quantum_Gravity_800x600.jpg

"The search for a quantum theory of gravity must include the recovery of the classical space-time".

Why? Ask yourselves what, physically, corresponds with the concepts of space, and time. Physics is supposed to be an objective explanation of physical existence (as manifest to us, ie not a belief system), and I can identify nothing that physically exists which could constitute either space or time.

Paul

Yuri

I have special point of view to Space-Time. I wrote about it to Dr. Stephen Weinberg.See my essay

http://fqxi.org/community/forum/topic/1413

Dear Yuri Bonder,

Continuum of eigen-rotational string of matters in Coherently-cyclic cluster-matter universe model, is analogue to space-time continuum; in that world line is applicable only for the macroscopic object of dense tetrahedral-branes to describe its path and not applicable for the dynamics of a string that differs from that of a particle.

With best wishes,

Jayakar

Dear ABCS,

I found your essay to be interesting. I am also intrigued by the mention of nonassociativity. Towards the end of my essay nonassociativity is briefly discussed. In further blog discussions more is discussed about this, where my work is a sort of prelude to nonassociative geometry. Your approach appears to be almost a pre-quantization procedure for the noncommutative geometry of spacetime. I will read your paper arXiv:1205.0501 for greater details.

Cheers LC

Dear Jayakar

I am not Yuri Bonder.My name is Yuri Danoyan.

For whom is your answer?

Hi All,

I read your essay with great interest. It is rather sobering from my point of view, since emergent spacetime is my own favorite way of thinking about quantum gravity. I have a few comments and questions.

1. Of the usual "discrete" FTS theories that you mention (LQG, CS, CDT), do you have one in mind more than the others in your research program?

2. On a related note, I am not quite sure if you are advocating the emergence of spacetime and matter-energy together from a single fundamental structure in the strongest possible sense. On page 2, you express the opinion that one must recover matter along with gravitation from the FTS, and on page 6 you mention the intimate connection between spacetime probes and spacetime itself, but on the other hand you mention "fundamental matter degrees of freedom" on page 9. Are you suggesting that there must be a division of information between "spacetime" and "matter-energy" even at the fundamental scale?

3. Covariance (Lorentz invariance, etc.) plays a major role here. On page 5, you point out the problem of observer-dependence of black-hole formation associated with arbitrary boosts, which is related to DSR and similar noncommutative theories that have "Lorentz invariance issues," and on page 6 you point out that a certain noncommutative structure associated with your CM calculations is Lorentz invariant. Now it seems to me that various types of "covariance breaking" that arise in QG might be best understood by simply interpreting covariance in a different way. So long as one insists that covariance is about symmetry, there will be problems with spacetime microstructure. But it one interprets covariance as being about something else, like order, these problems need not arise. I explain this further in my essay here On the Foundational Assumptions of Modern Physics.

4. In several places, you mention "correspondence principle-type" considerations involving classical limits, etc. From this point of view one regards "classical spacetime" as a suitable limit of a quantum theory. Feynman's sum-over-histories method is a complementary viewpoint: here one views "quantum spacetime" as a superposition of classical universes. I am interested to know if you have worked much from this point of view, since that is the approach I prefer.

Thanks for the great read, and I'd be grateful for your responses. Take care,

Ben Dribus

For better clarification my approach

I sending to you Frank Wilczek's 3 keen articles

http://ctpweb.lns.mit.edu/physics_today/phystoday/Abs_limits388.pdf

http://ctpweb.lns.mit.edu/physics_today/phystoday/Abs_limits393.pdf

http://ctpweb.lns.mit.edu/physics_today/phystoday/Abs_limits400.pdf

All the best

Dear All,

"Assuming that a classical underlying space-time geometry exists, how does the quantum nature of the available probing objects modify the way in which we perceive the geometry?"

I think you hit the nail on the head in your abstract. but also;

" ...characteristics of the center of mass of extended objects."

"...in order to calculate the center of mass of the complete extended

object, all the individual particles have to be identifed as such, as neglecting their internal compositeness would lead to inconsistencies."

"...the trajectories of localized objects that define the space-time geometry."

and the need to; "...revise the standard geometrical concepts and explore the corresponding notions that could have, at least in principle, operational meaning."

I fear your methodology and language may be too steeped in the old mainstream paradigm, but may be wrong as it is surely open minds that count.

Certainly I agree "the recovery of the classical space-time." from the quanta is the holy grail, or 'unification'.

Well written. I hope you may read and comment on the more 'Locally Real' approach I take in my own essay, with some exiting results, and look forward to your thoughts on those and commonality.

Very best wishes

Peter

PS. Paul; For 'space-time' I think you may first substitute CSL in your own language, but leading to gravity.

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

Dear authors, where the ontological foundations of geometry of space-time? I did not find it in the essay. Sincerely, Sara