Caplar, Neven


ETH Zürich

Doctorate at D-PHYS

HIT  J 33.3 

Wolfgang-Pauli-Str. 27

8093 Zürich


  • phone +41 44 633 38 26 
  • phone (Alt.) +41 44 633 75 64 
  • mail
  • vcard
  • vcard V-Card (vcf, 1kb)



Research activities

I am a Ph.D. student in the Observational cosmology group at ETH Zurich. My advisor is prof. Simon J. Lilly.  My research is primarily connected with various properties of AGNs (active galactic nuclei) .

In the first part of my Ph.D.  I studied global properties of AGNs by studying  the AGNs and  their host galaxies in a demographic fashion. I have been trying to understand how is the cosmic evolution of black holes and galaxies connected and what can we infer about it from the vast data available from galaxy surveys.  I have developed a simple phenomenological model that links the evolving galaxy mass function and the evolving quasar luminosity function and which makes specific and testable predictions. The most interesting result that I find is that the mass ratio between galaxies and their black holes much evolve quite strongly with redshift! Such evolution has many interesting implications on the black hole - galaxy co-evolution.

In the second part of my Ph.D. I have been local properties of AGN physics by studying AGN variability. With the constant influx of new data and new telescopes synoptic astronomy is starting to be important component of AGN research.  I have been studying AGN variability in optical regime by using PTF (Palomar Transient Factory) dataset. I characterized the properties of AGN optical variability from this very large photometric data set (2.4 million photometric data points) by using methods in both the time and frequency domain. I  re-calibrated the AGN ligth-curves and I have found that many quasar light-curves display power spectral densities that are significantly steeper than commonly used random walk model.  Re-calibrated data can be found here.

Large part of my initial work during my PhD has concentrated on the study of magnetic fields in galaxies at intermediate redshift. Many different observations that are available help us to constrain strength, origin, and importance of these fields in galaxy evolution. This project is now  pursued further by my fellow PhD student Kwang Song-Kim.

During my Master studies I have worked on theoretical cosmological models that can explain evolution of the Universe, usually described as evolution of dark matter and dark energy, as an evolution of one single dark fluid.

I enjoy data analysis and investigation of various data sets. I run a blog where I publish results of playing with various datasets, some of them of astrophysical origin. One of the larger projects, that has been done in collaboration with the Faculty of Electrical Engineering and Computing in Zagreb, investigated the performance metrics of players in a online multi-player game and has been presented on computer science conferences. Recently, with fellow Ph.D. students at ETH Zurich, I have led a study to quantify gender bias in the field of Astronomy. We have performed extensive analysis, using also machine-learning techniques to quantify and characterize the bias. We show that papers authored by female authors receive 10.4±0.9% fewer citations than what would be expected if the papers with the same non-gender specific properties were written by male authors. The data can be found here.




ADS Classic

ADS Bumblebee (log in needed)


Page URL:
Tue Jul 25 16:48:35 CEST 2017
© 2017 Eidgenössische Technische Hochschule Zürich