Ana Alonso-Serrano, Erickson Tjoa, Luis J. Garay, Eduardo Martín-Martínez
We analyze how the presence of closed timelike curves (CTCs) characterizing a time machine can be discerned by placing a local particle detector in a region of spacetime which is causally disconnected from the CTCs. Our study shows that not only can the detector tell if there are CTCs, but also that the detector can separate topological from geometrical information and distinguish periodic spacetimes without CTCs (like the Einstein cylinder), curvature, and spacetimes with topological identifications that enable time-machines.
{"title":"Particle detectors under chronological hazard","authors":"Ana Alonso-Serrano, Erickson Tjoa, Luis J. Garay, Eduardo Martín-Martínez","doi":"10.1007/jhep07(2024)001","DOIUrl":"https://doi.org/10.1007/jhep07(2024)001","url":null,"abstract":"<p>We analyze how the presence of closed timelike curves (CTCs) characterizing a time machine can be discerned by placing a local particle detector in a region of spacetime which is causally disconnected from the CTCs. Our study shows that not only can the detector tell if there are CTCs, but also that the detector can separate topological from geometrical information and distinguish periodic spacetimes without CTCs (like the Einstein cylinder), curvature, and spacetimes with topological identifications that enable time-machines.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arnau Bas i Beneito, John Gargalionis, Juan Herrero-García, Arcadi Santamaria, Michael A. Schmidt
Baryon number is an accidental symmetry of the Standard Model at the Lagrangian level. Its violation is arguably one of the most compelling phenomena predicted by physics beyond the Standard Model. Furthermore, there is a large experimental effort to search for it including the Hyper-K, DUNE, JUNO, and THEIA experiments. Therefore, an agnostic, model-independent, analysis of baryon number violation using the power of Effective Field Theory is very timely. In particular, in this work we study the contribution of dimension six and seven effective operators to |∆(B − L)| = 0, 2 nucleon decays taking into account the effects of Renormalisation Group Evolution. We obtain lower limits on the energy scale of each operator and study the correlations between different decay modes. We find that for some operators the effect of running is very significant.
{"title":"An EFT approach to baryon number violation: lower limits on the new physics scale and correlations between nucleon decay modes","authors":"Arnau Bas i Beneito, John Gargalionis, Juan Herrero-García, Arcadi Santamaria, Michael A. Schmidt","doi":"10.1007/jhep07(2024)004","DOIUrl":"https://doi.org/10.1007/jhep07(2024)004","url":null,"abstract":"<p>Baryon number is an accidental symmetry of the Standard Model at the Lagrangian level. Its violation is arguably one of the most compelling phenomena predicted by physics beyond the Standard Model. Furthermore, there is a large experimental effort to search for it including the Hyper-K, DUNE, JUNO, and THEIA experiments. Therefore, an agnostic, model-independent, analysis of baryon number violation using the power of Effective Field Theory is very timely. In particular, in this work we study the contribution of dimension six and seven effective operators to |∆(<i>B</i> − <i>L</i>)| = 0<i>,</i> 2 nucleon decays taking into account the effects of Renormalisation Group Evolution. We obtain lower limits on the energy scale of each operator and study the correlations between different decay modes. We find that for some operators the effect of running is very significant.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We consider effective field theories (EFTs) of scalar fields with broken Lorentz boosts, which arise by taking the decoupling and flat-space limits of the EFT of inflation, and derive constraints that must be satisfied by the corresponding scattering amplitudes if there is an underlying non-linearly realised symmetry. We primarily concentrate on extended shift symmetries which depend on the space-time coordinates, and find that combinations of scattering amplitudes obey enhanced Adler zeros. That is, such combinations vanish as one external momentum is taken soft, with the rate at which they vanish dictated by the corresponding symmetry. In our soft theorem derivation, we pay particular care to the energy and momentum-conserving delta functions that arise due to space-time translations, and show that when acted upon by derivatives with respect to spatial momenta, they yield a tower of soft theorems which are ultimately required for closure of the underlying symmetry algebra. All of our soft theorems correspond to constraints that must be satisfied by on-shell amplitudes and, even for symmetries that depend on the time coordinate, our soft theorems only require derivatives to be taken with respect to spatial momenta. We perform a soft bootstrap procedure to find solutions to our soft theorems, and compare these solutions to what we find from an off-shell analysis using the coset construction.
{"title":"Soft theorems for boostless amplitudes","authors":"Zong-Zhe Du, David Stefanyszyn","doi":"10.1007/jhep07(2024)011","DOIUrl":"https://doi.org/10.1007/jhep07(2024)011","url":null,"abstract":"<p>We consider effective field theories (EFTs) of scalar fields with broken Lorentz boosts, which arise by taking the decoupling and flat-space limits of the EFT of inflation, and derive constraints that must be satisfied by the corresponding scattering amplitudes if there is an underlying non-linearly realised symmetry. We primarily concentrate on extended shift symmetries which depend on the space-time coordinates, and find that <i>combinations</i> of scattering amplitudes obey enhanced Adler zeros. That is, such combinations vanish as one external momentum is taken soft, with the rate at which they vanish dictated by the corresponding symmetry. In our soft theorem derivation, we pay particular care to the energy and momentum-conserving delta functions that arise due to space-time translations, and show that when acted upon by derivatives with respect to spatial momenta, they yield a tower of soft theorems which are ultimately required for closure of the underlying symmetry algebra. All of our soft theorems correspond to constraints that must be satisfied by on-shell amplitudes and, even for symmetries that depend on the time coordinate, our soft theorems only require derivatives to be taken with respect to spatial momenta. We perform a soft bootstrap procedure to find solutions to our soft theorems, and compare these solutions to what we find from an off-shell analysis using the coset construction.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We revisit anomalies of (4, 0) and (3, 1) maximally supersymmetric tensor theories in d = 6. A (4, 0) on-shell tensor multiplet descends to that of the d = 5 maximal supergravity upon a dimensional reduction, hypothesized to offer a strong-coupled UV completion of the latter in the same sense of (2, 0) theories as the UV completion of d = 5 ( mathcal{N} ) = 2 pure Yang-Mills. The gravitational anomalies, found to be nonvanishing, had been computed, although its relevance in the absence of the d = 6 metric is not obvious. We perform a comprehensive anomaly computation for (4, 0) and (3, 1) tensor supermultiplets, respectively, for Sp(4) and Sp(3) × Sp(1) R-symmetry anomalies and the mixed R-gravitational anomaly thereof, and find that anomalies involving R-symmetries cancel out identically. We close with questions on how to address the anomaly in this class of theories with no general covariance.
我们重新审视了 d = 6 中(4,0)和(3,1)最大超对称张量理论的反常现象。一个(4,0)壳上张量多重子在降维后下降到d = 5最大超引力的张量多重子,被假设为后者提供了一个与(2,0)理论相同意义上的强耦合UV补全,就像d = 5 ( mathcal{N} ) = 2纯Yang-Mills的UV补全一样。我们计算了引力反常,发现它是非消失的,尽管在没有d = 6度量的情况下它的相关性并不明显。我们对(4,0)和(3,1)张量超多重子的 Sp(4)和 Sp(3)×Sp(1)R 对称反常及其混合 R 引力反常进行了全面的反常计算,发现涉及 R 对称的反常完全抵消。最后,我们提出了如何在这一类没有一般协方差的理论中解决反常现象的问题。
{"title":"Axial anomalies of maximally supersymmetric tensor theories","authors":"Piljin Yi, Yi Zhang","doi":"10.1007/jhep07(2024)007","DOIUrl":"https://doi.org/10.1007/jhep07(2024)007","url":null,"abstract":"<p>We revisit anomalies of (4, 0) and (3, 1) maximally supersymmetric tensor theories in <i>d</i> = 6. A (4, 0) on-shell tensor multiplet descends to that of the <i>d</i> = 5 maximal supergravity upon a dimensional reduction, hypothesized to offer a strong-coupled UV completion of the latter in the same sense of (2, 0) theories as the UV completion of <i>d</i> = 5 <span>( mathcal{N} )</span> = 2 pure Yang-Mills. The gravitational anomalies, found to be nonvanishing, had been computed, although its relevance in the absence of the <i>d</i> = 6 metric is not obvious. We perform a comprehensive anomaly computation for (4, 0) and (3, 1) tensor supermultiplets, respectively, for Sp(4) and Sp(3) × Sp(1) <i>R</i>-symmetry anomalies and the mixed <i>R</i>-gravitational anomaly thereof, and find that anomalies involving <i>R</i>-symmetries cancel out identically. We close with questions on how to address the anomaly in this class of theories with no general covariance.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We conduct a novel study to obtain the initial spin of the primordial black holes created during a first-order phase transition due to delayed false vacuum decay. Remaining within the parameter space consistent with observational bounds, we express the abundance and the initial spin of the primordial black holes as functions of the phase transition parameters. The abundance of the primordial black holes is extremely sensitive to the phase transition parameters. We also find that the initial spin weakly depends on all parameters except the transition temperature.
{"title":"Spinning primordial black holes from first order phase transition","authors":"Indra Kumar Banerjee, Ujjal Kumar Dey","doi":"10.1007/jhep07(2024)006","DOIUrl":"https://doi.org/10.1007/jhep07(2024)006","url":null,"abstract":"<p>We conduct a novel study to obtain the initial spin of the primordial black holes created during a first-order phase transition due to delayed false vacuum decay. Remaining within the parameter space consistent with observational bounds, we express the abundance and the initial spin of the primordial black holes as functions of the phase transition parameters. The abundance of the primordial black holes is extremely sensitive to the phase transition parameters. We also find that the initial spin weakly depends on all parameters except the transition temperature.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study charged scalar perturbations of charged extremal black holes in Einstein-Born-Infeld theory. Our numerical results indicate that these black holes all suffer from superradiant instability by the unstable quasi-bound states, regardless how small the coupling constant is. We therefore provide a new example that the superradiant stability of the Reissner-Nordström black hole is a fine-tuned result, as in the case when it is embedded in the STU supergravity model. The work is also motivated by the weak gravity conjecture since at the linear coupling constant level, the theory belongs to a subsect of four-derivative corrections in the effective field theory. Our results appear to support the notion that the black holes do decay when gravity is weaker by the correction, but the decaying halftime requires nonlinear effects and cannot be seen at the level of linear coupling constant. The full nonlinear effects also indicate that the black holes can decay even when gravity is stronger.
我们研究了爱因斯坦-天生-因费尔德理论中带电极值黑洞的带电标量扰动。我们的数值结果表明,无论耦合常数有多小,这些黑洞都会受到不稳定准约束态的超辐射不稳定性的影响。因此,我们提供了一个新的例子,说明赖斯纳-诺德斯特伦黑洞的超辐射稳定性是一个微调结果,就像它嵌入 STU 超引力模型的情况一样。这项工作还受到弱引力猜想的启发,因为在线性耦合常数水平上,该理论属于有效场论中四衍生修正的一个子部分。我们的研究结果似乎支持这样一种观点,即当引力因修正而变弱时,黑洞确实会衰变,但衰变的半衰期需要非线性效应,在线性耦合常数水平上无法看到。全非线性效应还表明,即使引力更强,黑洞也会衰变。
{"title":"Superradiant instability of charged extremal black holes in Einstein-Born-Infeld gravity","authors":"Zhe-Hua Wu, H. Lü","doi":"10.1007/jhep07(2024)003","DOIUrl":"https://doi.org/10.1007/jhep07(2024)003","url":null,"abstract":"<p>We study charged scalar perturbations of charged extremal black holes in Einstein-Born-Infeld theory. Our numerical results indicate that these black holes all suffer from superradiant instability by the unstable quasi-bound states, regardless how small the coupling constant is. We therefore provide a new example that the superradiant stability of the Reissner-Nordström black hole is a fine-tuned result, as in the case when it is embedded in the STU supergravity model. The work is also motivated by the weak gravity conjecture since at the linear coupling constant level, the theory belongs to a subsect of four-derivative corrections in the effective field theory. Our results appear to support the notion that the black holes do decay when gravity is weaker by the correction, but the decaying halftime requires nonlinear effects and cannot be seen at the level of linear coupling constant. The full nonlinear effects also indicate that the black holes can decay even when gravity is stronger.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Claude Duhr, Albrecht Klemm, Florian Loebbert, Christoph Nega, Franziska Porkert
We generalise the geometric analysis of square fishnet integrals in two dimensions to the case of hexagonal fishnets with three-point vertices. Our results support the conjecture that fishnet Feynman integrals in two dimensions, together with their associated geometry, are completely fixed by their Yangian and permutation symmetries. As a new feature for the hexagonal fishnets, the star-triangle identity introduces an ambiguity in the graph representation of a given Feynman integral. This translates into a map between different geometric interpretations attached to a graph. We demonstrate explicitly how these fishnet integrals can be understood as Calabi-Yau varieties, whose Picard-Fuchs ideals are generated by the Yangian over the conformal algebra. In analogy to elliptic curves, which represent the simplest examples of fishnet integrals with four-point vertices, we find that the simplest examples of three-point fishnets correspond to Picard curves with natural generalisations at higher loop orders.
{"title":"Geometry from integrability: multi-leg fishnet integrals in two dimensions","authors":"Claude Duhr, Albrecht Klemm, Florian Loebbert, Christoph Nega, Franziska Porkert","doi":"10.1007/jhep07(2024)008","DOIUrl":"https://doi.org/10.1007/jhep07(2024)008","url":null,"abstract":"<p>We generalise the geometric analysis of square fishnet integrals in two dimensions to the case of hexagonal fishnets with three-point vertices. Our results support the conjecture that fishnet Feynman integrals in two dimensions, together with their associated geometry, are completely fixed by their Yangian and permutation symmetries. As a new feature for the hexagonal fishnets, the star-triangle identity introduces an ambiguity in the graph representation of a given Feynman integral. This translates into a map between different geometric interpretations attached to a graph. We demonstrate explicitly how these fishnet integrals can be understood as Calabi-Yau varieties, whose Picard-Fuchs ideals are generated by the Yangian over the conformal algebra. In analogy to elliptic curves, which represent the simplest examples of fishnet integrals with four-point vertices, we find that the simplest examples of three-point fishnets correspond to Picard curves with natural generalisations at higher loop orders.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We compute the gluon beam function for jet-veto resummation to next-to-next-to-leading order (NNLO) in the strong-coupling expansion. Our calculation is based on an automated framework that was previously used for the computation of the respective quark beam function, and which we significantly extended for the present calculation. In particular, the perturbative matching kernels are directly calculated in momentum space, without the need to perform an additional Mellin transform. We present results for both gluon and quark-initiated processes, which we cross-checked with an independent semi-analytical method that exploits the similarity of the beam functions to the more familiar case of transverse-momentum resummation. Our computation is relevant for jet-veto resummations at NNLL′ accuracy.
{"title":"The NNLO gluon beam function for jet-veto resummation","authors":"Guido Bell, Kevin Brune, Goutam Das, Ding Yu Shao, Marcel Wald","doi":"10.1007/jhep07(2024)014","DOIUrl":"https://doi.org/10.1007/jhep07(2024)014","url":null,"abstract":"<p>We compute the gluon beam function for jet-veto resummation to next-to-next-to-leading order (NNLO) in the strong-coupling expansion. Our calculation is based on an automated framework that was previously used for the computation of the respective quark beam function, and which we significantly extended for the present calculation. In particular, the perturbative matching kernels are directly calculated in momentum space, without the need to perform an additional Mellin transform. We present results for both gluon and quark-initiated processes, which we cross-checked with an independent semi-analytical method that exploits the similarity of the beam functions to the more familiar case of transverse-momentum resummation. Our computation is relevant for jet-veto resummations at NNLL′ accuracy.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We propose an algebraic definition of ER=EPR in the GN → 0 limit, which associates bulk spacetime connectivity/disconnectivity to the operator algebraic structure of a quantum gravity system. The new formulation not only includes information on the amount of entanglement, but also more importantly the structure of entanglement. We give an independent definition of a quantum wormhole as part of the proposal. This algebraic version of ER=EPR sheds light on a recent puzzle regarding spacetime disconnectivity in holographic systems with ( mathcal{O} )(1/GN) entanglement. We discuss the emergence of quantum connectivity in the context of black hole evaporation and further argue that at the Page time, the black hole-radiation system undergoes a transition involving the transfer of an emergent type III1 subalgebra of high complexity operators from the black hole to radiation. We argue this is a general phenomenon that occurs whenever there is an exchange of dominance between two competing quantum extremal surfaces.
我们提出了 GN → 0 极限下 ER=EPR 的代数定义,它将大块时空的连通性/不连通性与量子引力系统的算子代数结构联系起来。新表述不仅包括纠缠量的信息,更重要的是包括纠缠结构的信息。作为建议的一部分,我们给出了量子虫洞的独立定义。ER=EPR的这一代数版本揭示了最近关于具有( mathcal{O} )(1/GN)纠缠的全息系统中时空断开性的谜题。我们在黑洞蒸发的背景下讨论了量子连通性的出现,并进一步论证了在黑洞-辐射系统发生转变的同时,涉及高复杂度算子的III1型子代数从黑洞向辐射的转移。我们认为这是一种普遍现象,只要两个相互竞争的量子极值表面之间发生支配权交换,就会出现这种现象。
{"title":"Algebraic ER=EPR and complexity transfer","authors":"Netta Engelhardt, Hong Liu","doi":"10.1007/jhep07(2024)013","DOIUrl":"https://doi.org/10.1007/jhep07(2024)013","url":null,"abstract":"<p>We propose an algebraic definition of ER=EPR in the <i>G</i><sub><i>N</i></sub> → 0 limit, which associates bulk spacetime connectivity/disconnectivity to the operator algebraic structure of a quantum gravity system. The new formulation not only includes information on the amount of entanglement, but also more importantly <i>the structure of entanglement</i>. We give an independent definition of a quantum wormhole as part of the proposal. This algebraic version of ER=EPR sheds light on a recent puzzle regarding spacetime disconnectivity in holographic systems with <span>( mathcal{O} )</span>(1<i>/G</i><sub><i>N</i></sub>) entanglement. We discuss the emergence of quantum connectivity in the context of black hole evaporation and further argue that at the Page time, the black hole-radiation system undergoes a transition involving the transfer of an emergent type III<sub>1</sub> subalgebra of high complexity operators from the black hole to radiation. We argue this is a general phenomenon that occurs whenever there is an exchange of dominance between two competing quantum extremal surfaces.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study a physically motivated representation of an algebra of operators in gravitational and non gravitational theories called the covariant representation of an algebra. This is a representation where the symmetries of the operator algebra are implemented unitarily on the Hilbert space. We emphasize the very close similarity of this representation to the crossed product of an algebra. In fact, as an example of (and sometimes identified with) a covariance algebra, the crossed product of an algebra is in one to one correspondence with the covariant representation of the algebra. This will in turn illuminate physically what the crossed product algebra is in the context of quantum gravity.
{"title":"Algebras and their covariant representations in quantum gravity","authors":"Eyoab Bahiru","doi":"10.1007/jhep07(2024)015","DOIUrl":"https://doi.org/10.1007/jhep07(2024)015","url":null,"abstract":"<p>We study a physically motivated representation of an algebra of operators in gravitational and non gravitational theories called the covariant representation of an algebra. This is a representation where the symmetries of the operator algebra are implemented unitarily on the Hilbert space. We emphasize the very close similarity of this representation to the crossed product of an algebra. In fact, as an example of (and sometimes identified with) a covariance algebra, the crossed product of an algebra is in one to one correspondence with the covariant representation of the algebra. This will in turn illuminate physically what the crossed product algebra is in the context of quantum gravity.</p>","PeriodicalId":635,"journal":{"name":"Journal of High Energy Physics","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}