Research and Teaching


Postdoctoral fellow

CERN, Theoretical Physics Department

Oct 2019 – Sep 2021 Geneva, Switzerland
I am a member of the heavy ion physics group at CERN Theoretical Physics Department.


Postdoctoral researcher

Heidelberg University, Institute for Theoretical Physics

Apr 2017 – Sep 2019 Heidelberg, Germany

I am a member of the collaborative research center “Isolated quantum systems and universality in extreme conditions”.

My work is centered on understanding the early times dynamics in heavy ion collisions and the universal aspects of loss of information. I am also interested in other stages of the collisions like hydrodynamic expansion and hadronization.

  • I co-wrote a kinetic pre-equilibrium propagator KøMPøST.
  • We found a pre-scaling regime in QCD kinetic theory.
  • We developed an efficient method of computing direct resonance decay products, see FastReso
  • I collaborate with heavy ion experimentalists Silvia Masciocchi, Klaus Reygers and Johanna Stachel in SFB projects A01 and C05 on the experimental signatures of non-equilibrium properties of QGP plasma.

Other experience:

Teaching experience:

  • Head tutor, Advanced Quantum Field Theory, summer semester 2019
  • Head tutor, Quantum Field Theory I, winter semester 2018-2019
  • Master seminar leader, QCD Matter in heavy ion collisions, summer semester 2018
  • Head tutor, Quantum Field Theory I, winter semester 2017-2018

Research and teaching assistant

Stony Brook University

Aug 2012 – Mar 2017 Stony Brook, NY, USA

I did my PhD work on Fluctuations in ultra-relativistic heavy ion collisions wth Derek Teaney in Nuclear Theory Group. My main research topics were:

Other experience:

  • I organised graduate student seminars in our group and co-organised group dinners and BBQs.

Teaching experience:

  • Recitation instructor, undergraduate electromagnetism and mechanics, Spring/Fall semesters 2014.
  • Teaching assistant, undergraduate mechanics laboratory, Fall/Spring semesters 2012-2013. Received David Fox award for the outstanding Teaching Assistant.

Research projects

I am interested in high multiplicity particle collisions at LHC and RHIC, because they can create Quark Gluon Plasma — a new form of matter, where protons and neutrons melt into quarks and gluons. Astonishingly, these tiny droplets of matter interact so strongly, that they can be effectively described as a fluid — the perfect fluid. Understanding the properties of QCD matter at extreme conditions is the aim of my research. Click on figures below to find out more!

Effective Kinetic Theory

Early dynamics with QCD Effective Kinetic Theory

Hydro Kinetics

Thermodynamic fluctuations in out-of-equilibrium hydro expansion

Principal Component Analysis

We analyse harmonic flows using Principal Component Analysis


Linear kinetic theory propagator for initial conditions of heavy ion collisions


Fast calculation of direct resonance decays


3D viscous relativistic hydrodynamics code.


  • aleksas.mazeliauskas at cern.ch
  • +41-22-76-73204
  • CERN dep TH 4-2-065, CH-1211 Geneva 23, Switzerland
  • aleksas.eu