Vacuum Energy through Krein Quantization Approach

In this paper, we consider a new version of indefinite metric field quantization called â Kreinâ quantization approach. Centering on the vacuum energy, fundamental subjects revolve around this concept will be discussed. In this approach, vacuum expectation value of the energy-momentum tensor can be defined properly and uniquely. Actually, no infinite term appears and the vacuum energy of the free field vanishes. These properties allow us to propose a discussion which creates an interesting link to cosmological constant problem. Achieving this goal, however, necessitates consistency of the theory with conventional ones, so we have studied and made comparison essential issues such as unitarity of the theory, physical achievements of renormalizing process and the trace anomaly subject.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author