7 papers
Spectral Density of the Causal Propagator
Joshua Y. L. Jones, Yasaman K. Yazdi
The causal propagator (or Pauli-Jordan function), which multiplied by is the spacetime commutator of the field , plays an essential role in scalar quantum field t…
Spectral Spacetime Entropy for Quasifree Theories
Joshua Y. L. Jones, Yasaman K. Yazdi
Motivated by the necessity to UV-regularise entanglement entropy, we present a spectral method for calculating the entropy of quasifree states, for both bosonic and fermionic field…
Fluctuations and Correlations in Causal Set Theory
Heidar Moradi, Yasaman K. Yazdi, Miguel Zilhão
We study the statistical fluctuations (such as the variance) of causal set quantities, with particular focus on the causal set action. To facilitate calculating such fluctuations,…
Aspects of Everpresent (II): Cosmological Tests of Current Models
Santanu Das, Arad Nasiri, Yasaman K. Yazdi
This paper investigates Everpresent , a stochastic dark energy model motivated by causal set theory and unimodular gravity, and confronts it with two key observational data sets…
Aspects of Everpresent (I): A Fluctuating Cosmological Constant from Spacetime Discreteness
Santanu Das, Arad Nasiri, Yasaman K. Yazdi
We provide a comprehensive discussion of the Everpresent cosmological model arising from fundamental principles in causal set theory and unimodular gravity. In this framework t…
Studies on the SJ Vacuum in de Sitter Spacetime
Sumati Surya, Nomaan X, Yasaman K. Yazdi
In this work we study the Sorkin-Johnston (SJ) vacuum in de Sitter spacetime for free scalar field theory. For the massless theory we find that the SJ vacuum can neither be obtaine…