相关论文: Joining the Hubble Flow: Implications for Expandin…
If cosmological perturbations in our Hubble sized volume are nongaussian, then they will be coupled to any larger perturbation modes outside our Hubble volume. This has important consequences for modeling inflation: the scalar power…
In the first section of these lectures I outline the classical framework of the Hubble classification system. Because of space limitations I will focus on points of controversy concerning the physical interpretation of the Hubble sequence,…
We try to understand how particles acquire mass in general, and in particular, how they acquire mass in the standard model and beyond.
If spacetime undergoes quantum fluctuations, an electromagnetic wavefront will acquire uncertainties in direction as well as phase as it propagates through spacetime. These uncertainties can show up in interferometric observations of…
Cosmology and particle physics have long been dominated by theoretical paradigms: Einstein's general theory of relativity in cosmology and the Standard Model of particle physics. The time may have come for paradigm shifts. Does cosmological…
The actual existence of collections of universes -- multiverses -- is strongly suggested by leading approaches to quantum cosmology, and has been proposed earlier as an attractive way to explain the apparent fine-tuned character of our…
I survey some of the developments in the theory of Ricci flow and its applications from the past decade. I focus mainly on the understanding of Ricci flows that are permitted to have unbounded curvature in the sense that the curvature can…
It is shown that the observed cmb dipole implies the existence of a center for the expansion of the universe, and that it can be explained by a combination of peculiar velocity and Hubble flow.
The evolution of matter in the expanding FRW universe during the time interval between the end of inflation and the beginning of the radiation-dominated era is studied. A constraint between the global geometry and total amount of matter in…
The local Hubble flow provides a valuable probe of the transition between cosmic expansion and nonlinear gravitational dynamics. On large scales, galaxies follow the linear Hubble law, but within group- and cluster-sized environments,…
We consider redshift drift in a general space-time as expressed in terms of physically interpretable multipole series. An important realisation from the derived results is that redshift drift cannot in general be thought of as a direct…
Two recent findings necessitate a closer look at the existing standard models of Particle Physics and Cosmology. These are the discovery of Neutrino oscillation, and hence a non zero mass on the one hand and, on the other, observations of…
In the picture of eternal inflation as driven by a scalar potential with multiple minima, our observable universe resides inside one of many bubbles formed from transitions out of a false vacuum. These bubbles necessarily collide, upsetting…
We review the general features of nonsingular universes ({\em i.e.} those that go from an era of accelerated collapse to an expanding era without displaying a singularity) as well as cyclic universes. We discuss the mechanisms behind the…
This study looks at motion of particles using mathematical methods of chronometric invariants (physical observable values in General Relativity). It is shown that aside for mass-bearing particles and light-like particles "zero-particles"…
The validity of Hubble's law defies the determination of the center of the big bang expansion, even if it exists. Every point in the expanding universe looks like the center from which the rest of the universe flies away. In this article,…
We consider cosmological evolution from the perspective of quantum information. We present a quantum circuit model for the expansion of a comoving region of space, in which initially-unentangled ancilla qubits become entangled as expansion…
Although the current galaxy models yield calculations consistent with much of the data, many irregularities exist, exceptions have been found to the current models, the $\Lambda$CDM model apparently fails on galaxy scales, dark matter…
Cosmology is intrinsically intertwined with questions in fundamental physics. The existence of non-baryonic dark matter requires new physics beyond the Standard Model of elemenatary-particle interactions and Einstein's general relativity,…
The phenomenon of the very local ($\le3$ Mpc) Hubble flow is studied on the basis of the data of recent precision observations. A set of computer simulations is performed to trace the trajectories of the flow galaxies back in time to the…