Related papers: Very Light Axion
The present status of superstring phenomenology is briefly discussed.
Here I present the effect of gaugino condensation and discrete symmetries to the model-independent axion potential, collaborated with Georgi and Nilles [hep-ph/9805510].
This Master of Science thesis treats the hypercharge axion, which is a hypothetical pseudo-scalar particle with electroweak interactions. First, the theoretical context and the motivations for this study are discussed. In short, the…
After a brief review of the axion solution of the strong CP problem, its supersymmetric extension and the superstring axion are discussed. I also present one interesting cosmological scenario, the axino-gravitino cosmology, for the large…
We illustrate, taking a top-down point of view, how axions and other very weakly interacting sub-eV particles (WISPs) arise in the course of compactification of the extra spatial dimensions in string/M-theory.
String theory, if it describes nature, is probably strongly coupled. As a result, one might despair of making any statements about the theory. In the framework of a set of clearly spelled out assumptions, we show that this is not…
I present a brief up-to-date review of the current understanding of Supergiant Fast X-ray Transients, with an emphasis on the observational point of view. After more than a decade since their discovery, a remarkable progress has been made…
We review the status of our knowledge on supergiant fast X-ray transients (SFXTs), a new hot topic in multi wavelength studies of binaries. We discuss the mechanisms believed to power these transients and then highlight the unique…
Light bosonic fields may suffer an instability around a rotating compact object. This process, known as superradiance, leads to the exponential amplification of the field around a black hole or neutron star, while the spin of the central…
In view of the ongoing galactic (or cosmic) axion detection experiments, we compare the axion-photon-photon coupling $c_{a\gamma\gamma}$'s for various invisible (or very light) axion models.
We revisit the limit on very light axion-like particles (ALPs) from the absence of gamma rays coincidental with the neutrino burst from SN1987A. We use updated supernova simulations, modern models for the magnetic field inside the Galaxy,…
Dark gauge sectors and axions are well-motivated in string theory. We demonstrate that if a confining gauge sector gives rise to dark glueballs that are a fraction of the dark matter, and the associated axion has a decay constant near the…
Consistent frameworks of quantum gravity often predict the existence of large numbers of ultralight pseudoscalar degrees of freedom, forming the phenomenological landscape of the String Axiverse. The complexity of the extra-dimensional…
Superstring theory involves a single unifying superstring current for bosons and fermions that in the low-energy limit generalizes the Klein-Gordon (not the Dirac) current. By adopting a relativistic-covariant probabilistic interpretation…
We generalize recent results on tachyon condensation in boundary string field theory to the superstring.
We argue that a new type of extremely light axion is generically present in the type IIB part of the string theory landscape. Its mass is suppressed by the third power of the warp factor of a strongly warped region (Klebanov-Strassler…
We use the linear supermultiplet formalism of supergravity to study axion couplings and chiral anomalies in the context of field-theoretical Lagrangians describing orbifold compactifications beyond the classical approximation. By matching…
Axions, grand unification, and string theory are each compelling extensions of the Standard Model. We show that combining these frameworks imposes strong constraints on the QCD axion mass. Using unitarity arguments and explicit string…
I review the theoretical motivation for the axion and present an update of the experimental status of axion searches. I finally comment on some aspects of the physics of axion-like particles.
We discuss the continuum field theory limit of the physical scenario described in Ref. [1], the universe arising from the interpretation of the most general collection of logical codes in terms of distributions of units of energy along…