Archivi tag: quantum gravity

Hot Topics in General Relativity and Gravitation

In this centennial anniversary of General Relativity, we will hold a conference on Hot Topics in General Relativity and Gravitation with the motivation to emphasize the tremendous progresses that have been made in Astrophysics and in Cosmology since Einstein’s discovery of General Relativity (GR) in 1915. This international conference will be held at ICISE as part of the Rencontres du Vietnam. Continua a leggere Hot Topics in General Relativity and Gravitation

Annunci

14th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories

The Fourteenth Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theory will take place at the University of Rome Sapienza July 12 – 18, 2015, celebrating the 100th anniversary of the Einstein equations as well as the International Year of Light under the aegis of the United Nations. Continua a leggere 14th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories

String Theory & Cosmology: New Ideas Meet New Experimental Data

This is the golden age of cosmology. Once a philosophical subject, cosmology has burgeoned into a precision science as ground and space-based astronomical observations supply a wealth of unprecedently precise cosmological measurements. Questions that were recently the stuff of speculation can now be analyzed in the context of rigorous, predictive theoretical frameworks whose viability is determined by observational data. To address key questions about our universe, especially at the energy scales characteristic of its earliest moments, one must invoke a theory of quantum gravity, such as string theory. Conversely, observational cosmology is our most promising window for testing fundamental theories at ultra-high energies. Continua a leggere String Theory & Cosmology: New Ideas Meet New Experimental Data

Probing the Fundamental Nature of Spacetime with the Renormalization Group

Renormalization group methods are a key element of theoretical particle physics and may also be central for constructing a fundamental theory of gravity, e.g., based on Weinberg’s asymptotic safety conjecture. The aim of this program is to bring together theorists and phenomenologists in order to discuss ideas related to the application of the renormalization group in quantum gravity and the consequences of asymptotic safety for cosmology, black holes and a possible ultraviolet completion of the standard model of particle physics including gravity. Continua a leggere Probing the Fundamental Nature of Spacetime with the Renormalization Group

International Conference on Quantum Gravity, Cosmology and String Theory

The Center for Fundamental Physics (CFP) at Zewail City of Science and Technology is organizing its first international conference on Quantum Gravity, Cosmology and String Theory (QGCS15) in Giza, Egypt from 11 to 15 January 2016.  Continua a leggere International Conference on Quantum Gravity, Cosmology and String Theory

Frontiers of Fundamental Physics 14

The 14th annual international symposium “Frontiers of Fundamental Physics” (FFP14) is organized by the Labex OCEVU. It will be held in Marseille, at the Faculty of Sciences of Aix Marseille University (AMU).  Continua a leggere Frontiers of Fundamental Physics 14

Lost in a multiverse

I recenti risultati pubblicati dal gruppo di Harvard sull’esperimento BICEP2 sono stati interpretati come la “prima evidenza diretta” dell’inflazione cosmica dovuta al passaggio delle onde gravitazionali primordiali le cui tracce sono state impresse nella radiazione cosmica di fondo (post). Non solo, ma c’è chi dice che questi dati potrebbero essere collegati a qualcosa ancora di più strano che gli astronomi chiamano multiverso. Secondo questa ipotesi affascinante, il nostro Universo non sarebbe l’unico ma sarebbe parte di una grande vastità di universi che formano una sorta di gigantesco “albero cosmico” il cui numero potrebbe essere dell’ordine di

quasi impronunciabile. Ma se questi universi esistono davvero, non li vediamo perchè dal momento in cui è nato il nostro Universo non c’è stato abbastanza tempo affinchè la luce si propagasse per raggiungere il nostro orizzonte cosmico. Dunque, essi si troverebbero al di là del nostro limite osservativo e perciò non potranno mai essere rivelati, almeno in linea di principio. Come fanno allora i cosmologi ad affermare che esistono invece delle evidenze a favore della loro esistenza?

Continua a leggere Lost in a multiverse