Abstract
Let × be a Poisson point process of intensity λ on the real line. A thickening of it is a (deterministic) measurable function f such that X∪f(X) is a Poisson point process of intensity λ′ where λ′ > λ. An equivariant thickening is a thickening which commutes with all shifts of the line. We show that a thickening exists but an equivariant thickening does not. We prove similar results for thickenings which commute only with integer shifts and in the discrete and multi-dimensional settings. This answers 3 questions of Holroyd, Lyons and Soo.
We briefly consider also a much more general setup in which we ask for the existence of a deterministic coupling satisfying a relation between two probability measures. We present a conjectured sufficient condition for the existence of such couplings.
Similar content being viewed by others
References
O. Angel, H. E. Alexander and T. Soo, Deterministic thinning of finite Poisson processes, Proceedings of the American Mathematical Society 139 (2011), 707–720.
Z. Artstein, Distributions of random sets and random selections, Israel Journal of Mathematics 46 (1983), 313–324.
K. Ball, Poisson thinning by monotone factors, Electronic Communications in Probability 10 (2005), 60–69, http://www.math.washington.edu/~ejpecp/EcpVol10/paper7.abs.html.
K. Ball, Monotone factors of i.i.d. processes, Israel Journal of Mathematics 150 (2005), 205–227.
B. Bollobás and N. Th. Varopoulos, Representation of systems of measurable sets, Mathematical Proceedings of the Cambridge Philosophical Society 78 (1975), 323–325.
A. E. Holroyd, R. Lyons and T. Soo, Poisson splitting by factors, Annals of Probability 39 (2011), 1938–1982.
K. Petersen, Ergodic Theory, Cambridge Studies in Advanced Mathematics, Vol. 2, Cambridge University Press, Cambridge, 1983.
Author information
Authors and Affiliations
Corresponding author
Additional information
Research of R.P. supported by NSF Grant OISE 0730136.
Rights and permissions
About this article
Cite this article
Gurel-Gurevich, O., Peled, R. Poisson thickening. Isr. J. Math. 196, 215–234 (2013). https://doi.org/10.1007/s11856-012-0181-2
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11856-012-0181-2