REVIEW
Symmetric teleparallel general relativity
General Relativity and Quantum Cosmology · Submitted 17 Sep 1998 · 23 references
Pith's verdict: A short, honest note that names symmetric teleparallel gravity and gets the algebra right; the geometric reframing is the contribution, and the authors are candid that no new calculation yet follows from it.
T0 · AI review
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Referee report
The paper
The paper claims
General relativity can be rewritten in a symmetric teleparallel geometry whose nonmetricity carries the gravitational force, turning the Einstein energy pseudotensor into a genuine tensor.
The reading
What carries the argument
The load-bearing device is the symmetric teleparallel connection: a connection with $R^����{}_����=0$ and $T^����=0$ but $Q_{����}=-Dg_{����}����0$, represented in a frame where its coefficients vanish. In that frame the coframe is closed, so locally $����^����=dx^����$ and the covariant derivative becomes $����_����$; the connection deformation $A^����{}_����$ reduces to minus the Christoffel symbol. This identity is what turns the standard $���� ����$ Lagrangian density into a covariant teleparallel Lagrangian and what promotes the Einstein pseudotensor to a tensor within the chosen geometry.
Extended reading notes
Core claim
The central claim is that general relativity admits a symmetric teleparallel representation: curvature and torsion vanish, nonmetricity does not, and the nonmetricity is the gravitational force. Starting from the decomposition of a general connection into the Levi-Civita connection plus contortion and nonmetricity terms, the authors set torsion to zero and choose a teleparallel frame with vanishing connection coefficients. Torsion-free flatness then forces the coframe to be a coordinate differential, $����^����=dx^����$ at least locally, so the deformation one-form is exactly $A^����{}_����=-����{����}����{����}����^����$. The Einstein-Hilbert Lagrangian minus a total derivative becomes the quadratic expression in Eq. (8), which is the standard coordinate Lagrangian but now read as a covariant object in the teleparallel geometry. Consequently the associated energy-momentum density, essentially the Einstein pseudotensor, is a true tensor: geometry-gauge dependent, but no longer a coordinate artifact.
Load-bearing premise
The construction needs a single teleparallel frame, equivalently a coordinate chart, in which the connection coefficients vanish and torsion is zero over the whole region where the energy-momentum tensor is claimed to be a true tensor; the paper establishes this only locally and notes that the formulation almost requires a global coordinate system.
Editorial extensions
If this is right
- Old coordinate calculations of gravitational energy, such as Tolman's use of the Einstein pseudotensor, become covariant calculations in a specified symmetric teleparallel geometry.
- The energy-momentum density is a tensor within that geometry, although changing the teleparallel connection changes the value, so the ambiguity is relocated from coordinates to a geometric gauge choice.
- Removing the total derivative from the Einstein-Hilbert action leaves a covariant, asymptotically convergent Lagrangian that generates a covariant energy-momentum tensor.
- The construction opens a five-parameter family of quadratic nonmetricity theories, of which the GR-equivalent case is only one member.
Reading between the lines
- Because the paper's frame is guaranteed only locally, a globally nontrivial spacetime may force a patchwork of STGR charts; a natural extension is to ask which topologies admit a single torsion-free teleparallel frame and how the energy tensor glues across overlaps.
- The energy density's dependence on the chosen connection suggests a test: compare STGR energy for a known exact solution with quasi-local energies such as the Brown-York or Bel-Robinson constructions; agreement in some gauge would give the tensor physical content beyond a relabelling.
- The five-parameter quadratic nonmetricity family is likely to contain extra propagating modes; a linearized analysis around Minkowski space could identify whether any member has ghosts, tachyons, or additional polarizations.
- Coupling STGR to fermions may be subtle: spinors need a teleparallel frame, but nonmetricity changes parallel transport, so the paper's warning that the GR interaction is not teleparallel minimal coupling could become a real consistency condition for matter.
Original abstract
General relativity can be presented in terms of other geometries besides Riemannian. In particular, teleparallel geometry (i.e., curvature vanishes) has some advantages, especially concerning energy-momentum localization and its ``translational gauge theory'' nature. The standard version is metric compatible, with torsion representing the gravitational ``force''. However there are many other possibilities. Here we focus on an interesting alternate extreme: curvature and torsion vanish but the nonmetricity $\nabla g$ does not---it carries the ``gravitational force''. This {\it symmetric teleparallel} representation of general relativity covariantizes (and hence legitimizes) the usual coordinate calculations. The associated energy-momentum density is essentially the Einstein pseudotensor, but in this novel geometric representation it is a true tensor.
The compiled record
The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.
The abstract, sentence by sentence
General relativity can be presented in terms of other geometries besides Riemannian. In particular, teleparallel geometry (i.e., curvature vanishes) has some advantages, especially concerning energy-momentum localization and its ``translational gauge theory'' nature. The standard version is metric compatible, with torsion representing the gravitational ``force''. However there are many other possibilities. Here we focus on an interesting alternate extreme: curvature and torsion vanish but the nonmetricity $\nabla g$ does not---it carries the ``gravitational force''. This {\it symmetric teleparallel} representation of general relativity covariantizes (and hence legitimizes) the usual coordinate calculations. The associated energy-momentum density is essentially the Einstein pseudotensor, but in this novel geometric representation it is a true tensor.
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | General relativity can be presented in terms of other geometries besides Riemannian. | background 1.00 | 0.05 | 0.04 | asserted 0.74 |
| s1 | In particular, teleparallel geometry (i.e., curvature vanishes) has some advantages, especially concerning energy-momentum localization and its ``translational gauge theory'' nature. | background 1.00 | 0.05 | 0.04 | asserted 0.93 |
| s2 | The standard version is metric compatible, with torsion representing the gravitational ``force''. | background 1.00 | 0.04 | 0.03 | asserted 1.00 |
| s3 | However there are many other possibilities. | background 0.91 | 0.05 | 0.03 | asserted 0.97 |
| s4 | Here we focus on an interesting alternate extreme: curvature and torsion vanish but the nonmetricity $\nabla g$ does not---it carries the ``gravitational force''. | contribution 0.94 | 0.26 | 0.30 | asserted 1.00 |
| s5 | This {\it symmetric teleparallel} representation of general relativity covariantizes (and hence legitimizes) the usual coordinate calculations. | interpretation 0.59 | 0.59 | 0.36 | asserted 1.00 |
| s6 | The associated energy-momentum density is essentially the Einstein pseudotensor, but in this novel geometric representation it is a true tensor. | result 0.71 | 0.69 | 0.30 | asserted 0.99 |
What was examined, and what was not
- arXiv listing abstract v2
- full text
- figures and tables
- references and citing sentences
- relations to other papers
- P abstract
- S sections
- T body sentences
- C citations
- R cross-paper relations
References
How the literature uses it
167 arXiv papers cite this in 223 sentences
Papers citing it · 63 sentences without a confident label
Builds on it 2 papers
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A possible action one can conceive in analogy to the teleparallel axion model [ref] as generalization of newer general relativity [ref] is then given by [equation] In the case that the parameters take the values [equation] one obtains the symmetric teleparallel equivalent of relativity [ref] (STEGR), together with symmetric teleparallel axion, which is non-minimally coupled to the unique parity-odd invariant of non-metricity.
Teleparallel axions and cosmology · Symmetric teleparallel axions · 0.96
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This will be the generalization of the symmetric teleparallel gravity [ref] .
Metric-Connection Geometries on Pre-Leibniz Algebroids: A Search for Geometrical Structure in String Models · Concluding Remarks · 0.88
Cites it as support 1 paper
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In symmetric teleparallel gravity [ref] , MCP is viable for all standard fields, including spinors [ref] .
The coupling of matter and spacetime geometry · Introduction · 0.99
Cites it as background 127 papers
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Among other possibilities, general relativity can be equivalently formulated in terms of the nonmetricity tensor [ref] , which measures the departure from zero of the covariant derivative of the metric tensor (see [ref] for an extensive review).
G\"odel-type spacetimes in $f(Q)$ gravity · Introduction · 0.99
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In this work we seek yet another explanation for the discrepancy as we study the evolution of matter perturbations in modified $F(Q)$ gravity [ref] , the nonlinear generalisation of the improved version of General Relativity [ref] on a flat and torsion-free spacetime continuum known as Symmetric Teleparallel Gravity (STG) [ref] .
Testing $F(Q)$ gravity with redshift space distortions · Introduction · 0.85
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A third, dynamically rich method has just been proposed: the symmetric teleparallel formulation [ref] , where gravity is fully given by the non-metricity scalar $Q$ and both curvature and torsion vanish, i.e. the $f(Q)$ gravity.
Cosmology of f(Q,L_m) gravity with Holographic Ricci Dark Energy: Early-Time Inflation and Late-Time Acceleration and RGUP Corrected Observables · Introduction · 0.97
Discussion
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