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MODIFICATION TO EINSTEIN'S FIELD EQUATIONS IMPOSED BY STRING THEORY AND CONSEQUENCES FOR THE CLASSICAL TESTS OF GENERAL RELATIVITY
Title
MODIFICATION TO EINSTEIN'S FIELD EQUATIONS IMPOSED BY STRING THEORY AND CONSEQUENCES FOR THE CLASSICAL TESTS OF GENERAL RELATIVITY.
Creator
Frye, Christopher, Efthimiou, Costas, University of Central Florida
Abstract / Description
String theory imposes slight modifications to Einstein's equations of general relativity. In Green, Schwarz, and Witten's classic text, the authors claim that the gravitational field equations in empty space should contain, in addition to the Ricci tensor, an extra term which is first order in the string constant alpha-prime and proportional to the Riemann curvature tensor squared. They do admit, however, that this simple modification is just schematic. We show that these modified equations...
Show moreString theory imposes slight modifications to Einstein's equations of general relativity. In Green, Schwarz, and Witten's classic text, the authors claim that the gravitational field equations in empty space should contain, in addition to the Ricci tensor, an extra term which is first order in the string constant alpha-prime and proportional to the Riemann curvature tensor squared. They do admit, however, that this simple modification is just schematic. We show that these modified equations do not admit an isotropic solution. We then investigate the consequences of the modified gravitational equations when they are coupled to the dilaton field. Callan, Myers, and Perry have found a static isotropic solution to these equations. We calculate the additional perihelion precession of Mercury, the added deflection of photons by the sun, and the extra gravitational redshift which should be present if these equations hold. We determine that additional effects due to string theory in each of these cases are quite minuscule.
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Date Issued
2013
Identifier
CFH0004411, ucf:45087
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0004411
THE EFFECTIVENESS OF TEACHING METHODS DESIGNED TO IMPROVE STUDENT ENGAGEMENT AND RETENTION OF PHYSICS SUBJECT MATTER FOR BOTH SCIENCE AND NON-SCIENCE MAJORS
Title
THE EFFECTIVENESS OF TEACHING METHODS DESIGNED TO IMPROVE STUDENT ENGAGEMENT AND RETENTION OF PHYSICS SUBJECT MATTER FOR BOTH SCIENCE AND NON-SCIENCE MAJORS.
Creator
Maronde, Dan, Efthimiou, Costas, University of Central Florida
Abstract / Description
The necessity of students' engagement with the subject matter for successful learning is well-documented in education research in general, and in physics education research in particular. This study examines the merits of two different programs designed to improve student learning through enhanced student engagement with the material. The target populations of the two programs are different: One is the group of students taking a physical science class as part of the general curriculum...
Show moreThe necessity of students' engagement with the subject matter for successful learning is well-documented in education research in general, and in physics education research in particular. This study examines the merits of two different programs designed to improve student learning through enhanced student engagement with the material. The target populations of the two programs are different: One is the group of students taking a physical science class as part of the general curriculum required of non-science, non-engineering majors; the other is the group of students, mostly in engineering disciplines, who must take the calculus-based introductory physics sequence as part of their majors' core curriculum. The physical science class is required for non-science majors due to the importance of having a science-literate public. To improve this group's engagement with the subject matter, Physics in Films approaches the subject in the context of scenes taken from popular Hollywood films. Students' learning in the class is evaluated by comparison between performance on pre- and post-tests. The students are also polled on their confidence in their answers on both tests, as an improved belief in their own knowledge is one of the goals of the class. For the calculus-based physics group, a large issue is retention within the major. Many students change to non-science majors before the completion of their degree. An improved understanding of the material in the introductory physics sequence should help alleviate this problem. The Physics Suite is a multi-part introductory physics curriculum based on physics education research. It has been shown to be effective in several studies when used in its entirety. Here, portions of the curriculum have been used in select sections of the introductory physics classes. Their effectiveness, both individually and in conjunction, is studied. Students' mastery of concepts is evaluated using pre- and post-tests, and effects on class performance and retention within the major are examined. Input from both groups of students in the study was obtained through interviews and surveys.
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Date Issued
2011
Identifier
CFE0003742, ucf:48793
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0003742