Gravitino mass runs with the inflaton field, so that a continuos spectrum of superheavy gravitinos emerges. Dec 19, 2016 gravitinos are assumed to be the lightest supersymmetric particles lsp and are nonthermally produced during inflation, in turn originated by a scalar with a starobinskys potential. This repulsive gravity drives the expansion of space restoring the true vacuum during the brief period of inflation which initiates the universe. Ppt inflation, gravity waves powerpoint presentation free to download id. Inflationary universe has become the standard cosmological scenario.
In particular, large field inflation in supergravity using one superfield. Yanagida, 2007 the decay of the inflaton in noscale supergravity j. Always the resulting decay rate of inflatons into bosons and fermions are mentioned without derivation in literature perhaps its assumed to be very simple. Why cosmic inflations last great prediction may fail forbes. Professor lorenzo sorbo this dissertation looks for possible observable signals of tensor metric perturbations.
T h e oscillating inflationary universe an d gravitational confinem ent a p p en d ix 2. There is a quantitative description of how small small must be for a given theory. There is no complete quantum field theory of gravitons due to an outstanding mathematical problem with renormalization in general relativity. Gravitational wave production through decay of the. Starobinskylike inflation and neutrino masses in a noscale so10. Jun 27, 2018 is it possible to estimate the rate of false vacuum decay in the inflationary universe by looking at the density perturbations in the big bang universe. Gravitational waves reveal the universe before the big. The isocurvature fluctuations are adequately suppressed, axions comprise the dark matter, proton lifetime estimates are of order 8e343e35 years, and the observed baryon asymmetry arises via nonthermal leptogenesis. And gravity repulses this substance, accelerating its growth because the negative pressure causes negative gravity. We analyze decay processes of the inflaton field, phi, during the coherent oscillation phase after inflation in fphir gravity. Gravitinos are assumed to be the lightest supersymmetric particles lsp and are nonthermally produced during inflation, in turn originated by a scalar with a starobinskys potential.
The planck space telescopes picture of the cosmic microwave. Question has been raised on this large f in the effective field theory framework and also quantum gravity effect may also ruin the axion symmetry at that scale. Is it possible to estimate the rate of false vacuum decay in the inflationary universe by looking at the density perturbations in the big bang universe. Inflation ended when the inflation field decayed into the particles we see in the universe today. Inflation cosmology simple english wikipedia, the free. May 06, 2016 from why guys have adams apples to if there are really bed bugs, we answer 10 of your most burning questions about life get your very own dolan shirts ht. Pdf axion inflation, proton decay and leptogenesis in. A note on gravitational particle production in supergravity. As a result, the adiabatic magnetic decay is not a priori guaranteed on super hubble scales.
Following the inflationary period, the universe continued to. Linde, 1984 chaotic inflation in supergravity, phys. Helical phase inflation and monodromy in supergravity theory. Based on the standard model of cosmology, the universe has been and is expanding.
In this note, we discuss the implications of the weak gravity conjecture wgc for general models of largefield inflation with a large number of axions n. In this scenario, the universes current expansion was preceded by a. Ppt inflation, gravity waves powerpoint presentation free. Inflation says that the universe has not always expanded at the same rate, and that the universe has experienced many periods of brief but immense. We first show that, from the bottomup perspective, such models admit a variety of different regimes for the enhancement of the effective axion decay constant, depending on the amount of alignment and the number of. We show a concrete calculation of the rate that the inflaton field decays into a pair of gauge fields via the trace anomaly. If you mean the mass and distance are fixed, how the parameter g, gravitat. The bigbang model leads to three important, experimentally testable predictions. The classical big bang theory assumes that the universe expanded at the same rate throughout universal history. After inflation, preheating is supposed as the mechanism which is responsible for restoring hot big bang.
In 1980, to explain the conditions observed in the. Therein, the etaproblem can be resolved relying on fundamental symmetries in the kaehler potential. From why guys have adams apples to if there are really bed bugs, we answer 10 of your most burning questions about life get your very own dolan shirts ht. Ppt reheating of the universe after inflation with ffr gravity. Although the field that drives inflation, which is by definition, called the inflation, is probably not the higgs field of the standard model. The inflation of the universe flattens the overall geometry. There is a curious similarity between this conception of the mechanics of inflation and the notion of a rebound at the end of a cosmic life cycle or big crunch in a closed, cyclic universe. In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the early universe. Natural inflation models in stringinspired supergravity. We first show that, from the bottomup perspective, such models admit a variety of different regimes for the enhancement of the effective axion decay constant, depending on the amount of alignment and the number of instanton terms that. Without inflation, these inhomogeneities grow because of gravity. Enhancement of the axion decay constant in inflation and the. In string theory, believed to be a consistent theory of quantum gravity, the graviton is a massless state. This relation between wavelength and massenergy is calculated with the planckeinstein relation, the same formula that relates electromagnetic wavelength to photon energy.
But the precise inflation mechanism is still unclear. Gravitational wave production through decay of the inflaton. Inflation, gravity waves a free powerpoint ppt presentation displayed as a flash slide show on id. First, the model predicts that as the universe expands, galaxies recede from one another with a velocity. The m in the equation means the mass of the two objects and r represents the distance between the center of mass. So if there is just one field phi dominating, plus gravity, inflation can occur if dvphid phi is small for whatever values of phi describes the universe at that time. Assuming the only relevant force is gravity, the future of the universe depends on its density which will tell us the mass, hence gravitational pull, of the universe. The weak gravity conjecture, if valid, rules out simple models of natural inflation by restricting their axion decay constant to be subplanckian.
Although recently, actually, in the past few years, people have written a number of papers proposing that maybe the higgs field of the. In helical phase inflation, as will be shown later, the phase monodromy in superpotential can be easily. In this letter we discuss another interesting aspect of this model, related to gravitino production, with emphasis on the corresponding mass spectrum. Researchers can concoct different inflationary theories by adjusting the shape of the energy density curve as long as there is a relatively stable false vacuum in the beginning. The coherent enhancement mechanism allows one to reduce an inflation model with an arbitrary potential to an effective model of natural inflation, i. And indeed, inflation is very much modeled on the higgs field. Professor lorenzo sorbo this dissertation looks for possible observable signals of tensor. We implement inflation in a nonsupersymmetric su5 model based on a nonminimal coupling of the axion field to gravity. In this scenario, the universes current expansion was preceded by a phase of contraction, yielding similar benefits to. T h e inflationary universe scenario an d q u an tu m cosm ology 1 4. Natural inflation models in stringinspired supergravity tetsutaro higaki. It is inevitable that the inflaton decays gravitationally into gauge fields in the presence of fphir coupling.
Remove this presentation flag as inappropriate i dont like this i like this remember as a favorite. You can come up with models of multifield inflation, quantumgravityinspired inflation, string theory inflation, etc. Gravitino and polonyi production in supergravity springerlink. Directions many different areas are under study in the inflationary scenario. Instead, after inflation, largescale magnetic fields obey a powerlaw solution, where one of the modes drops at a rate slower than the adiabatic. Max describes the inflation period as containing a nondiluting, inflating substance, where the energy used to inflate it causes its mass to increase through extreme negative pressure. Note that the inflaton cannot decay through the super weylkahler and sigmamodel anomaly effects 56 57 58, because the kahler potential does not depend on the inflaton.
We argue that a nonminimal coupling of the matter and gravitational sectors results in a change in particlemomentum on a cosmological timescale, irrespective of particle creation or decay. Concretely, we investigate explicit realizations of superpotentials, in which the flatness of the inflaton potential is protected at tree level by a. We derive constraints on both inflation models and supersymmetry breaking. T h e in flation ary u n iverse stanford university. If we find a positive signal for r, either a chaotic inflation typically if r 0. In the classical big bang theory this was a problem because the uniform expansion would mean that objects would have to travel many times the speed of light to. The spontaneous inflaton decay induced by supergravity effect was. Supergravity is a wellmotivated theory beyond the standard model. There is a characteristic time the doubling time in which the size of the universe would double. The adobe flash plugin is needed to view this content. We revisit stringy attempts to realise natural inflation, with a single open string axionic inflaton from dbranes in a warped throat. After inflation, perturbative decay of inflaton also produces polonyi particles that rapidly decay into gravitinos. Mar 17, 2014 inflation is the mysterious force that blew up the scale of the infant universe from submicroscopic to gargantuan in a fraction of a second.
The equation about universal gravity is as follows. Spontaneous decay of inflatons to bosons powerpoint presentation free to view id. By using this axionic shift symmetry a natural inflation has been proposed in. Pdf primordial monopoles, proton decay, gravity waves. In the usual axion natural inflation, the axion decay constant is predicted to be in the super planckian regime which is believed to be incompatible with an effective field theory framework. Sep 28, 2017 as alternative to inflation, steinhardt et al. Bicep2, primordial gravity waves, and cosmic inflation. Besides quadratic inflation, the phase monodromy for helical phase inflation can be easily modified to realize natural inflation, in which the process of integrating out heavy fields fulfills the phaseaxion alignment indirectly and leads to super planckian phase decay constant with consistent field stabilization as well. Jan 07, 2016 if we find a positive signal for r, either a chaotic inflation typically if r 0. Inflation in supergravity with a single superfield inspire. In spite of its viability, observation suggests that axion decay constant should be f. Inflation is the mysterious force that blew up the scale of the infant universe from submicroscopic to gargantuan in a fraction of a second. Gravitational waves reveal the universe before the big bang.
The inflaton also directly decays into a pair of the gravitinos. In the first part of this thesis, we study classes of hybrid and chaotic inflation models in fourdimensional n1 supergravity. Pdf we implement inflation in a nonsupersymmetric su5 model based on a nonminimal coupling of the axion field to gravity. Ppt inflation, gravity waves powerpoint presentation. Inflation says that objects that were previously in close proximity to one another were separated very quickly during a period of inflation, so the temperature balance was still held. In this case, a more complicated mass density spectrum. Kinetic gravity braiding and axion inflation sciencedirect. Inducedgravity gutscale higgs inflation in supergravity. Recent observations of the cosmic microwave background radiation in the postinflationary universe support the inflation theory. Other than for strictly personal use, it is not permitted to download or to. Always the resulting decay rate of inflatons into bosons and fermions are mentioned without derivation in. In theories of quantum gravity, the graviton is the hypothetical quantum of gravity, an elementary particle that mediates the force of gravity. Inflation and density perturbations physics forums.
With a novel mechanism originating from a higher derivative kinetic gravity. At the heart of the european space agency spacecraft, chilled to 0. Largefield inflation with multiple axions and the weak. University of groningen inflation coone, andries alexander rug. The uv completion of more general f r gravity models can provide a unifying picture of dark matter, dark energy and inflation. Cosmic inflation, the process the bicep2 results appear to have vindicated, occurred before the big bang by this definition. Reheating of the universe after inflation with ffr gravity. Enhancement of the axion decay constant in inflation and.
Shift symmetry and higgs inflation in supergravity with. Apr 03, 2014 cosmic inflation, the process the bicep2 results appear to have vindicated, occurred before the big bang by this definition. We demonstrate how to realize within supergravity a novel chaotictype inflationary scenario driven by the radial parts of a conjugate pair of higgs superfields causing the spontaneous breaking of a grand unified gauge symmetry at a scale assuming the value of the supersymmetric grand unification scale. The decay of the inflation field produced enough energy to heat the universe so that the remainder of the big bang became the hot big bang that produced the universe we see today. Reheating processes after starobinsky inflation in oldminimal. There is the outside possibility that cosmic bubble collisions could be visible in the cmb. Particles and fields 878 december 2012 with 42 reads how we measure reads. We constructed a new class of inflationary model with the higher derivative axion field which obeys constant shift symmetry. Particle physics models of inflation in supergravity and. R 2 super gravity lead to starobinskys potential, in a onefield setting for inflationary cosmology that appears favored by planck data.
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