The universe from a single particle

Motion and observation in a single-particle universe

We outline an argument that a single-particle universe (a universe containing precisely one pointlike particle) can be described mathematically, in which observation can be considered meaningful despite the a priori impossibility of distinguishing between an observer and the observed. Moreover, we argue, such a universe can be observationally similar to the world we see around us. It is arguabl...

Particle creation in a toroidal universe

Although current astrophysical observations provide precise information on the geometry of the universe [1], its topology remains a mystery. We don’t even know whether the universe is compact or infinite. Nevertheless, lower bounds can be placed on its size for each compact topology (see Ref. [2] and references therein). Amongst the possible topologies for the universe, those with some or all s...

Particle Physics in the Early Universe

Particle Physics as a Building Block of the Universe

The Standard Model in particle physics describes the forces, components and reactions of the basic particles that make up matter. Also it predicts that there is an elementary particle, the Higgs boson, which would produce the effect of mass. In this paper we have first focused some important milestones of physical laws extending to standard model. We have then considered some particulars of Hig...

The Dyer - Roeder relation in a universe with particle production

We have obtained analytical exact solutions of the Dyer-Roeder equation in a cosmological model where creation of particles occurs at the expenses of the gravitational field. We discussed the influences of in-homogeneities in the path of a light beam on the apparent diameter of astrophysical objects and consider both redshift independent as redshift dependent distributions of the inhomogeneities.