We consider the annihilation process of an electron-positron pair into a pair of heavier fermions when the initial electron and positron beams are polarized. By calculating the polarization of the final-state particles, we discuss in detail the effect due to the produced particle masses in the T-charm energy region at BEPC/BES, and also compare the effect with that at the B-factory. Such a study is useful for the design of possible polarization investigation at the BEPC/BES facility and the B-factory.
The newly proposed entropic gravity suggests gravity as an emergent force rather than a fundamental one. In this approach,the Newtonian constant G does not play a fundamental role any more, and a new fundamental constant is required to replace itsposition. This request also arises from some philosophical considerations to contemplate the physical foundations for the unificationof theories. We here consider the suggestion to derive G from more fundamental quantities in the presence of a new fundamentallength scale l, which is suspected to originate from the structure of quantum space-time, and can be measured directly from Lorentz-violating observations. Our results are relevant to the fundamental understanding of physics, and more practically, of natural units,as well as explanations of experimental constraints in searching for Lorentz violation.
We report that a general principle of physical independence of mathematical background manifolds brings a replacement of common derivative operators by co-derivative ones. Then we obtain a new Lagrangian for the ordinary minimal standard model with supplementary terms containing the Lorentz invariance violation information measured by a new matrix, denoted as the Lorentz invariance violation matrix. We thus provide a new fundamental theory to study Lorentz invariance violation effects consistently and systematically.