Our picks for fourth quarter 2010 MIP (most important QG paper)

[marcus]

Of these fifteen candidates, please select the paper or papers which you think will contribute most significantly to future quantum gravity research. Multiple choice is possible in the poll, so please choose several if you wish. The papers' abstract summaries follow in the next post.

Big Bounce in Dipole Cosmology
Marco Valerio Battisti, Antonino Marcianò
http://arxiv.org/abs/1010.1258
http://arxiv.org/cits/1010.1258

Simple model for quantum general relativity from loop quantum gravity
Carlo Rovelli
http://arxiv.org/abs/1010.1939
http://arxiv.org/cits/1010.1939

Operator Spin Foam Models
Benjamin Bahr, Frank Hellmann, Wojciech Kamiński, Marcin Kisielowski, Jerzy Lewandowski
http://arxiv.org/abs/1010.4787
http://arxiv.org/cits/1010.4787

Observing the Big Bounce with Tensor Modes in the Cosmic Microwave Background
Julien Grain, A. Barrau, T. Cailleteau, J. Mielczarek
http://arxiv.org/abs/1011.1811
http://arxiv.org/cits/1011.1811

Generalized Spinfoams
You Ding, Muxin Han, Carlo Rovelli
http://arxiv.org/abs/1011.2149
http://arxiv.org/cits/1011.2149

Inflation and Loop Quantum Cosmology
Aurelien Barrau
http://arxiv.org/abs/1011.5516
http://arxiv.org/cits/1011.5516

Coherent states for FLRW space-times
Elena Magliaro, Antonino Marcianò, Claudio Perini
http://arxiv.org/abs/1011.5676
http://arxiv.org/cits/1011.5676

Lorentz covariance of loop quantum gravity
Carlo Rovelli, Simone Speziale
http://arxiv.org/abs/1012.1739
http://arxiv.org/cits/1012.1739

Matter in inhomogeneous loop quantum cosmology: the Gowdy T³ model
Mercedes Martín-Benito, Daniel Martín-de Blas, Guillermo A. Mena Marugán
http://arxiv.org/abs/1012.2324
http://arxiv.org/cits/1012.2324

Planck Scale Cosmology and Asymptotic Safety in Resummed Quantum Gravity
B.F.L. Ward
http://arxiv.org/abs/1012.2680
http://arxiv.org/cits/1012.2680

The Universal RG Machine
Dario Benedetti, Kai Groh, Pedro F. Machado, Frank Saueressig
http://arxiv.org/abs/1012.3081
http://arxiv.org/cits/1012.3081

Renormalization Group Flow of the Holst Action
J.-E. Daum, M.Reuter
http://arxiv.org/abs/1012.4280
http://arxiv.org/cits/1012.4280

Loop quantum gravity: the first twenty five years
Carlo Rovelli
http://arxiv.org/abs/1012.4707
http://arxiv.org/cits/1012.4707

Spinfoam fermions
Eugenio Bianchi, Muxin Han, Elena Magliaro, Claudio Perini, Carlo Rovelli, Wolfgang Wieland
http://arxiv.org/abs/1012.4719
http://arxiv.org/cits/1012.4719

Quantum deformation of two four-dimensional spin foam models
Winston J. Fairbairn, Catherine Meusburger
http://arxiv.org/abs/1012.4784
http://arxiv.org/cits/1012.4784

Included are some which could have a significant bearing on QG even though not restricted to the field itself. As usual with these quarterly polls, the focus is on non-string QG research.

 

[marcus]

Here are the abstracts:

http://arxiv.org/abs/1010.1258
Big Bounce in Dipole Cosmology
Marco Valerio Battisti, Antonino Marcianò
(Submitted on 6 Oct 2010)
"We derive the cosmological Big Bounce scenario from the dipole approximation of Loop Quantum Gravity. We show that a non-singular evolution takes place for any matter field and that, by considering a massless scalar field as a relational clock for the dynamics, the semi-classical proprieties of an initial state are preserved on the other side of the bounce. This model thus enhances the relation between Loop Quantum Cosmology and the full theory."

http://arxiv.org/abs/1010.1939
Simple model for quantum general relativity from loop quantum gravity
Carlo Rovelli
(Submitted on 10 Oct 2010)
"New progress in loop gravity has lead to a simple model of `general-covariant quantum field theory'. I sum up the definition of the model in self-contained form, in terms accessible to those outside the subfield. I emphasize its formulation as a generalized topological quantum field theory with an infinite number of degrees of freedom, and its relation to lattice theory. I list the indications supporting the conjecture that the model is related to general relativity and UV finite."

http://arxiv.org/abs/1010.4787
Operator Spin Foam Models
Benjamin Bahr, Frank Hellmann, Wojciech Kamiński, Marcin Kisielowski, Jerzy Lewandowski
(Submitted on 22 Oct 2010)
"The goal of this paper is to introduce a systematic approach to spin foams. We define operator spin foams, that is foams labelled by group representations and operators, as the main tool. An equivalence relation we impose in the set of the operator spin foams allows to split the faces and the edges of the foams. The consistency with that relation requires introduction of the (familiar for the BF theory) face amplitude. The operator spin foam models are defined quite generally. Imposing a maximal symmetry leads to a family we call natural operator spin foam models. This symmetry, combined with demanding consistency with splitting the edges, determines a complete characterization of a general natural model. It can be obtained by applying arbitrary (quantum) constraints on an arbitrary BF spin foam model. In particular, imposing suitable constraints on Spin(4) BF spin foam model is exactly the way we tend to view 4d quantum gravity, starting with the BC model and continuing with the EPRL or FK models. That makes our framework directly applicable to those models. Specifically, our operator spin foam framework can be translated into the language of spin foams and partition functions. We discuss the examples: BF spin foam model, the BC model, and the model obtained by application of our framework to the EPRL intertwiners."

http://arxiv.org/abs/1011.1811
Observing the Big Bounce with Tensor Modes in the Cosmic Microwave Background: Phenomenology and Fundamental LQC Parameters
Julien Grain, A. Barrau, T. Cailleteau, J. Mielczarek
(Submitted on 8 Nov 2010)
"Cosmological models where the standard Big Bang is replaced by a bounce have been studied for decades. The situation has however dramatically changed in the last years for two reasons. First, because new ways to probe the early Universe have emerged, in particular thanks to the Cosmic Microwave Background (CMB). Second, because some well grounded theories -- especially Loop Quantum Cosmology -- unambiguously predict a bounce, at least for homogeneous models. In this article, we investigate into the details the phenomenological parameters that could be constrained or measured by next-generation B-mode CMB experiments. We point out that an important observational window could be opened. We then show that those constraints can be converted into very meaningful limits on the fundamental Loop Quantum Cosmology (LQC) parameters. This establishes the early universe as an invaluable quantum gravity laboratory."

http://arxiv.org/abs/1011.2149
Generalized Spinfoams
You Ding, Muxin Han, Carlo Rovelli
(Submitted on 9 Nov 2010)
"We reconsider the spinfoam dynamics that has been recently introduced, in the generalized Kaminski-Kisielowski-Lewandowski (KKL) version where the foam is not dual to a triangulation. We study the Euclidean as well as the Lorentzian case. We show that this theory can still be obtained as a constrained BF theory satisfying the simplicity constraint, now discretized on a general oriented 2-cell complex. This constraint implies that boundary states admit a (quantum) geometrical interpretation in terms of polyhedra, generalizing the tetrahedral geometry of the simplicial case. We also point out that the general solution to this constraint (imposed weakly) depends on a quantum number r_f in addition to those of loop quantum gravity. We compute the vertex amplitude and recover the KKL amplitude in the Euclidean theory when r_f=0. We comment on the eventual physical relevance of r_f, and the formal way to eliminate it."

http://arxiv.org/abs/1011.5516
Inflation and Loop Quantum Cosmology
Aurelien Barrau
(Submitted on 24 Nov 2010)
"On the one hand, inflation is an extremely convincing scenario: it solves most cosmological paradoxes and generates fluctuations that became the seeds for the growth of structures. It, however, suffers from a 'naturalness' problem: generating initial conditions for inflation is far from easy. On the other hand, loop quantum cosmology is very successful: it solves the Big Bang singularity through a non-perturbative and background-independent quantization of general relativity. It, however, suffers from a key drawback: it is extremely difficult to test. Recent results can let us hope that inflation and LQC could mutually cure those pathologies: LQC seems to naturally generate inflation and inflation could allow us to test LQC."

http://arxiv.org/abs/1011.5676
Coherent states for FLRW space-times
Elena Magliaro, Antonino Marcianò, Claudio Perini
(Submitted on 25 Nov 2010)
"We construct a class of coherent spin-network states that capture proprieties of curved space-times of the Friedmann-Lamaître-Robertson-Walker type on which they are peaked. The data coded by a coherent state are associated to a cellular decomposition of a spatial (t=const.) section with dual graph given by the complete five-vertex graph, though the construction can be easily generalized to other graphs. The labels of coherent states are complex SL(2,C) variables, one for each link of the graph and are computed through a smearing process starting from a continuum extrinsic and intrinsic geometry of the canonical surface. The construction covers both Euclidean and Lorentzian signatures; in the Euclidean case and in the limit of flat space we reproduce the simplicial 4-simplex semiclassical states used in Spin Foams."

http://arxiv.org/abs/1012.1739
Lorentz covariance of loop quantum gravity
Carlo Rovelli, Simone Speziale
6 pages, 1 figure
(Submitted on 8 Dec 2010)
"The kinematics of loop gravity can be given a manifestly Lorentz-covariant formulation: the conventional SU(2)-spin-network Hilbert space can be mapped to a space K of SL(2,C) functions, where Lorentz covariance is manifest. K can be described in terms of a certain subset of the 'projected' spin networks studied by Livine, Alexandrov and Dupuis. It is formed by SL(2,C) functions completely determined by their restriction on SU(2). These are square-integrable in the SU(2) scalar product, but not in the SL(2,C) one. Thus, SU(2)-spin-network states can be represented by Lorentz-covariant SL(2,C) functions, as two-component photons can be described in the Lorentz-covariant Gupta-Bleuler formalism. As shown by Wolfgang Wieland in a related paper, this manifestly Lorentz-covariant formulation can also be directly obtained from canonical quantization. We show that the spinfoam dynamics of loop quantum gravity is locally SL(2,C)-invariant in the bulk, and yields states that are preciseley in K on the boundary. This clarifies how the SL(2,C) spinfoam formalism yields an SU(2) theory on the boundary. These structures define a tidy Lorentz-covariant formalism for loop gravity."

http://arxiv.org/abs/1012.2324
Matter in inhomogeneous loop quantum cosmology: the Gowdy T³ model
Mercedes Martín-Benito, Daniel Martín-de Blas, Guillermo A. Mena Marugán
12 pages, submitted to PRD
(Submitted on 10 Dec 2010)
"We apply a hybrid approach which combines loop and Fock quantizations to fully quantize the linearly polarized Gowdy T³ model in the presence of a massless scalar field with the same symmetries as the metric. Like in the absence of matter content, the application of loop techniques leads to a quantum resolution of the classical cosmological singularity. Most importantly, thanks to the inclusion of matter, the homogeneous sector of the model contains flat Friedmann-Robertson-Walker (FRW) solutions, which are not allowed in vacuo. Therefore, this model provides a simple setting to study at the quantum level interesting physical phenomena such as the effect of the anisotropies and inhomogeneities on flat FRW cosmologies."

http://arxiv.org/abs/1012.2680
Planck Scale Cosmology and Asymptotic Safety in Resummed Quantum Gravity
B.F.L. Ward (Department of Physics, Baylor University, Waco, TX)
5 pages; presented by B.F.L. Ward at ICHEP 2010
(Submitted on 13 Dec 2010)
"In Weinberg's asymptotic safety approach, a finite dimensional critical surface for a UV stable fixed point generates a theory of quantum gravity with a finite number of physical parameters. We argue that, in an extension of Feynman's original formulation of the theory, we recover this fixed-point UV behavior from an exact re-arrangement of the respective perturbative series. Our results are consistent with the exact field space Wilsonian renormalization group results of Reuter et al. and with recent Hopf-algebraic Dyson-Schwinger renormalization theory results of Kreimer. We obtain the first "first principles" predictions of the dimensionless gravitational and cosmological constants and our results support the Planck scale cosmology of Bonanno and Reuter. We conclude with an estimate for the currently observed value of the cosmological constant."

http://arxiv.org/abs/1012.3081
The Universal RG Machine
Dario Benedetti, Kai Groh, Pedro F. Machado, Frank Saueressig
38 pages
(Submitted on 14 Dec 2010)
"Functional Renormalization Group Equations constitute a powerful tool to encode the perturbative and non-perturbative properties of a physical system. We present an algorithm to systematically compute the expansion of such flow equations in a given background quantity specified by the approximation scheme. The method is based on off-diagonal heat-kernel techniques and can be implemented on a computer algebra system, opening access to complex computations in, e.g., Gravity or Yang-Mills theory. In a first illustrative example, we re-derive the gravitational beta-functions of the Einstein-Hilbert truncation, demonstrating their background-independence. As an additional result, the heat-kernel coefficients for transverse vectors and transverse-traceless symmetric matrices are computed to second order in the curvature."

http://arxiv.org/abs/1012.4280
Renormalization Group Flow of the Holst Action
J.-E. Daum, M.Reuter
11 pages, 3 figures
(Submitted on 20 Dec 2010)
"The renormalization group (RG) properties of quantum gravity are explored, using the vielbein and the spin connection as the fundamental field variables. The scale dependent effective action is required to be invariant both under space time diffeomorphisms and local frame rotations. The nonperturbative RG equation is solved explicitly on the truncated theory space defined by a three parameter family of Holst-type actions which involve a running Immirzi parameter. We find evidence for the existence of an asymptotically safe fundamental theory, probably inequivalent to metric quantum gravity constructed in the same way."

http://arxiv.org/abs/1012.4707
Loop quantum gravity: the first twenty five years
Carlo Rovelli
(Submitted on 21 Dec 2010)
"This is a review paper invited by the journal 'Classical ad Quantum Gravity' for a 'Cluster Issue' on approaches to quantum gravity. I give a synthetic presentation of loop gravity. I spell-out the aims of the theory and compare the results obtained with the initial hopes that motivated the early interest in this research direction. I give my own perspective on the status of the program and attempt of a critical evaluation of its successes and limits."

http://arxiv.org/abs/1012.4719
Spinfoam fermions
Eugenio Bianchi, Muxin Han, Elena Magliaro, Claudio Perini, Carlo Rovelli, Wolfgang Wieland
8 pages
(Submitted on 21 Dec 2010)
"We describe a minimal coupling of fermions and Yang Mills fields to the loop quantum gravity dynamics. The coupling takes a very simple form."

http://arxiv.org/abs/1012.4784
Quantum deformation of two four-dimensional spin foam models
Winston J. Fairbairn, Catherine Meusburger
38 pages, 3 figures
(Submitted on 21 Dec 2010)
"We construct the q-deformed version of two four-dimensional spin foam models, the Euclidean and Lorentzian EPRL model. The q-deformed models are based on the representation theory of two copies of U_q(su(2)) at a root of unity and on the quantum Lorentz group with a real deformation parameter. For both models we give a definition of the quantum EPRL intertwiners, study their convergence and braiding properties and construct an amplitude for the four-simplexes. We find that both of the resulting models are convergent."

 

[marcus]

The week between Christmas and New Year's is apt to be slow. Not much gets posted. So I set the poll up on 24 December instead of waiting untll the end of the month. If an especially good paper comes out during the last week of the year we can add it on to the January 2011 list and include it in the next poll.

EDIT: Arxiv says they will only post on Wednesday 29 December during the pre-NewYear week. So if they hold to that, we will have a real lull.

 

[marcus]

Finbar, Kevin, PAllen, thanks for helping get the poll of to a good start!

 

[marcus]

So far 6 people have responded in just the first couple of days. I'm wondering: should we try to pick MIPs for the entire year?

It could be that this fourth quarter list already has the year's top papers (that they just happened to all appear in the last three months.) In that case a 2010 MIP poll would be in some sense superfluous.

atyy, Finbar, francesca, Kevin, PAllen, thanks for for sharing your perspective on current QG research output. I hope more people will respond---it's helpful to see different views of what are the most significant developments. I learn from it, and expect that others of us do as well.

In case anyone wants to look back, the second quarter poll had some major papers:
https://www.physicsforums.com/showthread.php?t=413838

 

[marcus]

One thing we could gradually do is in the case of each paper say in simple terms why it seems important, or likely to turn out to be significant in future QG developments. The following comments are merely my opinion, feel welcome to add your own take on any of these.
Big Bounce in Dipole Cosmology
Marco Valerio Battisti, Antonino Marcianò
http://arxiv.org/abs/1010.1258
Loop people are just beginning to replace the simplified LQC model with the full spinfoam theory. Bounce is generic in simple LQC (with its small numbers of degrees of freedom). Will the bounce carry over to full LQG treatment? The early universe model is the key to testability. Battisti Marcianò suggest bounce and testability will carry over to full theory.
First result of this type.

Simple model for quantum general relativity from loop quantum gravity
Carlo Rovelli
http://arxiv.org/abs/1010.1939
Review paper, much of it aimed at mathematicians. Elegant "Feynman rules" formulation of the theory. Concise. Review/survey articles always useful, good to have even if presenting no special new results.

Operator Spin Foam Models
Benjamin Bahr, Frank Hellmann, Wojciech Kamiński, Marcin Kisielowski, Jerzy Lewandowski
http://arxiv.org/abs/1010.4787
Lewandowski is a strong mathematician. He rationalizes generalizes and "rigorizes". He has a history of making Lqg more rigorous and this actually preparing the way for progress. I can't tell the possible consequence of this more general defintion of spinfoam. Compatting with matter? Don't know. Just rely on Jerzy's track record and wait and see.

Observing the Big Bounce with Tensor Modes in the Cosmic Microwave Background
Julien Grain, A. Barrau, T. Cailleteau, J. Mielczarek
http://arxiv.org/abs/1011.1811
Of course! This is the empirical, observational angle. It's so important!

Generalized Spinfoams
You Ding, Muxin Han, Carlo Rovelli
http://arxiv.org/abs/1011.2149
Well they have been trying out spinfoams as the basis for Lqg dynamics, and as usual Rovelli starts with the simplified version and gradually works towards the full formulation. For a long time they have been restricting the spinfoams to be basically dual to a 4-simplex (five-sider) triangulation. So each vertex has 5 edges. But Lewandowski says let's generalize and open it up, can you handle any number of edges? Vertices with any "valence"? At some point this had to be faced.

Inflation and Loop Quantum Cosmology
Aurelien Barrau
http://arxiv.org/abs/1011.5516
More about the empirical observational connection. Barrau is great.

Coherent states for FLRW space-times
Elena Magliaro, Antonino Marcianò, Claudio Perini
http://arxiv.org/abs/1011.5676
Other people keep referring to this paper, and other about semiclassical-peaked states. I take it on faith that coherent states in Lqg are an important development. And look! This is about *standard FLRW cosmology*. This is the standard universe model that all cosmologists use and that a huge amount of data is being fitted to. So it has to matter, even if I am not clear exactly how.

Lorentz covariance of loop quantum gravity
Carlo Rovelli, Simone Speziale
http://arxiv.org/abs/1012.1739
We kind of figured all along it could be Lorentz covariant, hadn't been proven NOT to be. But finally this had to be addressed. An explicit formulation of LQG which is manifestly Lorentz covariant.

Matter in inhomogeneous loop quantum cosmology: the Gowdy T³ model
Mercedes Martín-Benito, Daniel Martín-de Blas, Guillermo A. Mena Marugán
http://arxiv.org/abs/1012.2324
I'm running out of steam, maybe someone else will volunteer an interpretation. Inhomogeneous sounds good---always trying relax restrictions and homogeneity is a big one. Matter sounds good.

Planck Scale Cosmology and Asymptotic Safety in Resummed Quantum Gravity
B.F.L. Ward
http://arxiv.org/abs/1012.2680
I know several other people are especially interested in *Asymptotic Safety* gravity. We have a bunch of AS papers on the poll. Maybe someone will volunteer comment.

The Universal RG Machine
Dario Benedetti, Kai Groh, Pedro F. Machado, Frank Saueressig
http://arxiv.org/abs/1012.3081
Another AsymSafe paper. Volunteer comment anyone?

Renormalization Group Flow of the Holst Action
J.-E. Daum, M.Reuter
http://arxiv.org/abs/1012.4280
The Holst action is the basis of Spinfoam QG! Martin Reuter has been a major developer of AsymSafe ever since 1998. He has more papers than anyone else including Percacci and Weinberg. He has always done AS with *metric* GR and no Immirzi parameter. Now a big opening in the LQG direction! He formulates AS with *connection* variables and with Immirzi parameter! Extends a hand in the LQG direction. Could be important.

Loop quantum gravity: the first twenty five years
Carlo Rovelli
http://arxiv.org/abs/1012.4707
Great review article.

Spinfoam fermions
Eugenio Bianchi, Muxin Han, Elena Magliaro, Claudio Perini, Carlo Rovelli, Wolfgang Wieland
http://arxiv.org/abs/1012.4719
OK Importance is clear.

Quantum deformation of two four-dimensional spin foam models
Winston J. Fairbairn, Catherine Meusburger
http://arxiv.org/abs/1012.4784
Quantum groups. Maybe someone else can put this paper in perspective for us. Can anyone comment?

 

[marcus]

Thanks to all who've responded to the fourth quarter poll so far! It's interesting to see what papers other people think will be of value to future research---and which are seen as important.

So far, nine of us have registered our picks:
Atyy
Finbar
Francesca
Inflector
Kevin
MTd2
Murray
myself
PAllen

And the leading 5 choices, to date, are

Spinfoam Fermions 5
The Universal RG Machine 3
Planck Scale Cosmology and Asymptotic Safety in Resummed Quantum Gravity 2
Renormalization Group Flow of the Holst Action 2
Quantum deformation of two four-dimensional spin foam models 2

It's interesting that 3 of our top five are about Asymptotic Safety. In another thread, one of the respondents, I think it was Murray, said that AS has developed some "momentum" (as a research program) recently.

If anyone wants to elaborate on that, feel free. I'd be interested to see people's reasons for making the assessment they did. Don't hesitate if you have a point to make about the way QG research is going or an argument to make in favor of a favorite.

 

[marcus]

It has been the custom to use the tail of the previous quarter's MIP poll thread as a kind of corral in which to gather and select papers for the next quarter's poll.

Now we are nearing the end of the first quarter 2011, and there are a lot of strong papers to pick from. I will list some here tentatively to get an idea of what the field looks like:

http://arxiv.org/abs/1101.0590
http://arxiv.org/cits/1101.0590
Diffeomorphisms in group field theories

http://arxiv.org/abs/1101.0931
http://arxiv.org/cits/1101.0931
The principle of relative locality

http://arxiv.org/abs/1101.3264
http://arxiv.org/cits/1101.3264
Spinfoam Fermions: PCT Symmetry, Dirac Determinant, and Correlation Functions

http://arxiv.org/abs/1101.3660
http://arxiv.org/cits/1101.3660
Detailed black hole state counting in loop quantum gravity

http://arxiv.org/abs/1101.4049
http://arxiv.org/cits/1101.4049
Cosmological constant in spinfoam cosmology

http://arxiv.org/abs/1101.5061
http://arxiv.org/cits/1101.5061
A Short and Subjective Introduction to the Spinfoam Framework for Quantum Gravity

http://arxiv.org/abs/1101.5401
http://arxiv.org/cits/1101.5401
Asymptotically Safe Cosmology

http://arxiv.org/abs/1101.5792
http://arxiv.org/cits/1101.5792
Particle Creation by Loop Black Holes

http://arxiv.org/abs/1101.6078
http://arxiv.org/cits/1101.6078
State sum models, induced gravity and the spectral action

http://arxiv.org/abs/1102.0954
http://arxiv.org/cits/1102.0954
The Holst Action by the Spectral Action Principle

http://arxiv.org/abs/1102.3660
http://arxiv.org/cits/1102.3660
Zakopane lectures on loop gravity

http://arxiv.org/abs/1102.3929
http://arxiv.org/cits/1102.3929
The Semiclassical Limit of Causal Dynamical Triangulations

http://arxiv.org/abs/1102.4755
http://arxiv.org/cits/1102.4755
Path Integral and Effective Hamiltonian in Loop Quantum Cosmology

http://arxiv.org/abs/1102.5012
http://arxiv.org/cits/1102.5012
Asymptotically Safe Lorentzian Gravity

http://arxiv.org/abs/1103.1597
http://arxiv.org/cits/1103.1597
On the Asymptotics of Quantum Group Spinfoam Model

http://arxiv.org/abs/1103.2475
http://arxiv.org/cits/1103.2475
Probability of Inflation in Loop Quantum Cosmology

http://arxiv.org/abs/1103.2723
http://arxiv.org/cits/1103.2723
The SU(2) Black Hole entropy revisited

 

[atyy]

How about http://arxiv.org/abs/1101.4182 ?

 

[marcus]

Good suggestion! I agree that this Gurau Rivasseau GFT paper is likely to be influential in future research and widely cited (at least comparatively so, nonstring quantum gravity/geometry is still a small field.)
We now have some 16 papers on the list and the month is not yet over. Some will probably have to be dropped but I guarantee the Gurau Rivasseau will stay and be in the poll.

 

[atyy]

And http://arxiv.org/abs/1103.4602

 

[marcus]

And http://arxiv.org/abs/1103.4602

Let me spell it out and study it more carefully. They are new Marseille PhDs who are now postdoc at Penn State. They have collaborated before on significant papers (with Bianchi or others, I forget exactly.)

Curvature in spinfoams
Elena Magliaro, Claudio Perini
6 pages, 3 figure
(Submitted on 23 Mar 2011)
"We consider spinfoam quantum gravity. We show in a simple case that the amplitude projects over a nontrivial (curved) classical geometry. This suggests that, at least for spinfoams without bubbles and for large values of the boundary spins, the amplitude takes the form of a path integral over Regge metrics, thus enforcing discrete Einstein equations in the classical limit."

This does seem to be another important step in gradually completing the verification of the classical limit. (Or ultimately failing! which is of course possible. )

==========================
So far 11 people have contributed their MIP choice(s) to the poll. The Generalized Spinfoams paper by Muxin Han et al recently picked up 2 votes. Thanks all! It's instructive (at least to me) to review everyones' picks.

Atyy
Finbar
Francesca
Inflector
Kevin
MTd2
Murray
myself
PAllen
Schreiberdk
Tom Stoer

 

[marcus]

Time to get the first quarter 2011 list in order:

[text: Multiple choices are possible in the poll, so please select several papers if you wish. Of these twenty candidates, choose the paper or papers which you think will contribute most significantly to future quantum gravity research. Abstract summaries follow in the next post.]

Diffeomorphisms in group field theories
Aristide Baratin, Florian Girelli, Daniele Oriti
http://arxiv.org/abs/1101.0590
http://arxiv.org/cits/1101.0590

The principle of relative locality
Giovanni Amelino-Camelia, Laurent Freidel, Jerzy Kowalski-Glikman, Lee Smolin
http://arxiv.org/abs/1101.0931
http://arxiv.org/cits/1101.0931

Spinfoam Fermions: PCT Symmetry, Dirac Determinant, and Correlation Functions
Muxin Han, Carlo Rovelli
http://arxiv.org/abs/1101.3264
http://arxiv.org/cits/1101.3264

Cosmological constant in spinfoam cosmology
Eugenio Bianchi, Thomas Krajewski, Carlo Rovelli, Francesca Vidotto
http://arxiv.org/abs/1101.4049
http://arxiv.org/cits/1101.4049

Asymptotically Safe Cosmology
Mark Hindmarsh, Daniel Litim, Christoph Rahmede
http://arxiv.org/abs/1101.5401
http://arxiv.org/cits/1101.5401

Particle Creation by Loop Black Holes
Emanuele Alesci, Leonardo Modesto
http://arxiv.org/abs/1101.5792
http://arxiv.org/cits/1101.5792

State sum models, induced gravity and the spectral action
John W. Barrett
http://arxiv.org/abs/1101.6078
http://arxiv.org/cits/1101.6078

Zakopane lectures on loop gravity
Carlo Rovelli
http://arxiv.org/abs/1102.3660
http://arxiv.org/cits/1102.3660

The Semiclassical Limit of Causal Dynamical Triangulations
J. Ambjorn, A. Gorlich, J. Jurkiewicz, R. Loll, J. Gizbert-Studnicki, T. Trzesniewski
http://arxiv.org/abs/1102.3929
http://arxiv.org/cits/1102.3929

Path Integral and Effective Hamiltonian in Loop Quantum Cosmology
Haiyun Huang, Yongge Ma, Li Qin
http://arxiv.org/abs/1102.4755
http://arxiv.org/cits/1102.4755

Asymptotically Safe Lorentzian Gravity
Elisa Manrique, Stefan Rechenberger, Frank Saueressig
http://arxiv.org/abs/1102.5012
http://arxiv.org/cits/1102.5012

On the Asymptotics of Quantum Group Spinfoam Model
You Ding, Muxin Han
http://arxiv.org/abs/1103.1597
http://arxiv.org/cits/1103.1597

Hamiltonian analysis of SO(4,1) constrained BF theory
R. Durka, J. Kowalski-Glikman
http://arxiv.org/abs/1003.2412
http://arxiv.org/cits/1003.2412

Probability of Inflation in Loop Quantum Cosmology
Abhay Ashtekar, David Sloan
http://arxiv.org/abs/1103.2475
http://arxiv.org/cits/1103.2475

The SU(2) Black Hole entropy revisited
Jonathan Engle, Karim Noui, Alejandro Perez, Daniele Pranzetti
http://arxiv.org/abs/1103.2723
http://arxiv.org/cits/1103.2723

Gravity as a constrained BF theory: Noether charges and Immirzi parameter
R. Durka, J. Kowalski-Glikman
http://arxiv.org/abs/1103.2971
http://arxiv.org/cis/1103.2971

Bubble divergences: sorting out topology from cell structure
Valentin Bonzom, Matteo Smerlak
http://arxiv.org/abs/1103.3961
http://arxiv.org/cits/1103.3961

The 1/N expansion of colored tensor models in arbitrary dimension
Razvan Gurau, Vincent Rivasseau
http://arxiv.org/abs/1101.4182
http://arxiv.org/cits/1101.4182

Curvature in spinfoams
Elena Magliaro, Claudio Perini
http://arxiv.org/abs/1103.4602
http://arxiv.org/cits/1103.4602

Gamma ray burst delay times probe the geometry of momentum space
Laurent Freidel, Lee Smolin
http://arxiv.org/abs/1103.5626
http://arxiv.org/cits/1103.5626

Awful lot of papers. Had to weed some out.