{"title":"A Four-Parameter Black-Hole Solution in the Bumblebee Gravity Model","authors":"R. Xu","doi":"10.1142/9789811275388_0036","DOIUrl":"https://doi.org/10.1142/9789811275388_0036","url":null,"abstract":"The bumblebee gravity model includes a class of vector-tensor theories of gravitation where the vector field couples to the Ricci tensor quadratically. We obtain an analytical spherical black-hole solution in this model. The solution has four parameters, expanding the two-parameter solution family known in the literature. Special choices of the parameters are pointed out and discussed.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131956661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New Developments in the Hamiltonian Formulation of the Gravitational Standard-Model Extension","authors":"M. Schreck","doi":"10.1142/9789811275388_0027","DOIUrl":"https://doi.org/10.1142/9789811275388_0027","url":null,"abstract":"This chapter of the proceedings for the Ninth Meeting on CPT and Lorentz Symmetry is dedicated to the Hamiltonian formulation of the minimal gravitational Standard-Model Extension. Some theoretical questions associated with the latter shall be reviewed. First, we recall the properties of the Hamiltonian, which was computed elsewhere, and discuss how it is linked to the modified Einstein equations. Second, we describe how the covariant and Hamiltonian formulations are shown to be consistent with each other.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121405951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lorentz Violation, CPT Violation, and Spectroscopy Experiments","authors":"Arnaldo J. Vargas","doi":"10.1142/9789811275388_0017","DOIUrl":"https://doi.org/10.1142/9789811275388_0017","url":null,"abstract":"This presentation discusses some of the signals for Lorentz violation potentially observable in atomic spectroscopy and clock-comparison experiments. The emphasis of the discussion is on how the angular-momentum quantum numbers of the states involved in the transition determine the properties of the possible sidereal variation of the transition frequency.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125030353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Search for CPT- and Lorentz-Invariance Violation in the Muon g-2 Experiment at Fermilab","authors":"B. Mitra","doi":"10.1142/9789811275388_0054","DOIUrl":"https://doi.org/10.1142/9789811275388_0054","url":null,"abstract":"Muon g-2 data can be used to study sidereal variation of anomalous muon precession rate, which is one of the important signatures of CPT and Lorentz invariance violation. The discussion in this proceeding will focus on the framework which has been used to study sidereal variation of anomalous muon precession rate in Muon g-2 Run 2 data. Also, a brief introduction will be given about the blinding framework which will be used on Run 2/3 data of Muon g-2 experiment. This blinding framework will keep the actual result of the experiment masked from the analyzer during the analysis process.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115821361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Antimatter Research: Advances of AEḡIS","authors":"Benjamin Rienacker","doi":"10.1142/9789811275388_0041","DOIUrl":"https://doi.org/10.1142/9789811275388_0041","url":null,"abstract":"The AEgIS collaboration is underway to directly measure the gravitational free-fall of neutral antimatter atoms. The experiment recently succeded in producing a pulsed cold antihydrogen source for the first time, and has now entered into its second phase, which aims at the formation of a slow antihydrogen beam and subseuqently a first proof-of-concept gravitational measurement. Major upgrades have been made, such as an improved antihydrogen production scheme and a new state-of-the-art antiproton trap. AEgIS was also connected to CERN's new antiproton deceleration facility ELENA and achieved first antiproton catching in late 2021.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"129 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126325777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"In-Beam Hyperfine Spectroscopy of Antihydrogen, Hydrogen, and Deuterium","authors":"E. Widmann","doi":"10.1142/9789811275388_0008","DOIUrl":"https://doi.org/10.1142/9789811275388_0008","url":null,"abstract":"The ASACUSA collaboration is developing a polarized beam of antihydrogen atoms to precisely determine the ground-state hyperfine structure for studies of CPT and Lorentz invariance. Using a beam of ordinary hydrogen, measurements of both the $sigma$ and $pi$-transition have been performed, investigating orientation-dependent SME coefficients. Furthermore a first hyperfine experiment with a beam of deuterium is being prepared.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117090051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Calculations in Lorentz-Breaking Scalar QED","authors":"Jean Felipe, A. Petrov, A. Scarpelli, L. Brito","doi":"10.1142/9789811275388_0063","DOIUrl":"https://doi.org/10.1142/9789811275388_0063","url":null,"abstract":"We purpose a study a Lorentz-breaking extension of the scalar QED. We calculate the contributions in the Lorentz-violating parameters to the two-point functions of scalar and gauge fields. We found that the two background tensors, coming from the two sectors (scalar and gauge) are mixed in the one-loop corrections. This shows that these two Lorentz-breaking terms cannot be studied in an isolated form.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129183390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cosmology in Symmetric Teleparallel Bumblebee Gravity","authors":"J. E. G. Silva","doi":"10.1142/9789811275388_0038","DOIUrl":"https://doi.org/10.1142/9789811275388_0038","url":null,"abstract":"Symmetric teleparallel gravity (STG) is an alternative description of the gravitational field as an effect of the nonmetricity rather than the curvature of the spacetime. For an specific choice of the symmetric teleparallel lagrangian, the STG dynamics is equivalent to the general relativity (GR), and it is called Symmetric teleparallel equivalent to general relativity (STEGR). We propose a local Lorentz violating dynamics in the gravitational sector in the STEGR framework. The Lorentz violation is trigged by the vacuum expectation value (vev) of the well-known bumblebee field, whose vev couples to the nonmetricity tensor. The effects of such couplings on the cosmological evolution is investigated.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"24 16","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114017462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Concepts in Lorentz and CPT Violation","authors":"A. Kostelecký","doi":"10.1142/9789811275388_0006","DOIUrl":"https://doi.org/10.1142/9789811275388_0006","url":null,"abstract":"This contribution to the CPT'22 meeting provides a brief review of some concepts in Lorentz and CPT violation.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126316003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Searching for Lorentz-Violating Signatures in Astrophysical Photon Observations","authors":"Jun-Jie Wei","doi":"10.1142/9789811275388_0032","DOIUrl":"https://doi.org/10.1142/9789811275388_0032","url":null,"abstract":"As a basic symmetry of Einstein's theory of special relativity, Lorentz invariance has withstood very strict tests. But there are still motivations for such tests. Firstly, many theories of quantum gravity suggest violations of Lorentz invariance at the Planck energy scale. Secondly, even minute deviations from Lorentz symmetry can accumulate as particle travel across large distances, leading to detectable effects at attainable energies. Thanks to their long baselines and high-energy emission, astrophysical observations provide sensitive tests of Lorentz invariance in the photon sector. In this paper, I briefly introduce astrophysical methods that we adopted to search for Lorentz-violating signatures, including vacuum dispersion and vacuum birefringence.","PeriodicalId":104099,"journal":{"name":"CPT and Lorentz Symmetry","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130415286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}