Galaxies are not closed boxes. Rather, they are intimately linked to large reservoirs of gas surrounding them within their host dark matter halos (the circumgalactic medium, CGM), or outside the halos (the intergalactic medium, IGM). These shape galaxy evolution through cycles of gas accretion, star-formation, galactic outflows and reaccretion, known as the cosmic baryon cycle. A detailed understanding of the physical properties of the C/IGM is thus crucial for understanding galaxy evolution. At high redshift, z~(1-6) near the peak of galaxy formation, the baryon cycle is far more intense than in the local Universe. The growth of large-scale structure triggers thermal instabilities and creates a multiphase IGM. Cold streams of dense gas flowing along cosmic web filaments penetrate the hot CGM, filling the halo with Lyman alpha emission and potentially leading to globular cluster formation. Intense accretion triggers violent disk instability (VDI) in galactic disks, resulting in the formation of giant clumps and intense starbursts.

My research addresses multiple aspects of this cycle, combining analytical models, idealized simulations, and fully cosmological simulations. 

My full publications list can be found in the link above as well as in my CV.

Below I briefly describe some of my work.


Resolving the CGM and the IGM in Cosmological Simulations

Stability of Cold Flows

Formation of Globular Clusters

The Origin of VDI

Lifetime and Evolution of Giant Clumps

The AGORA Collaboration

The VELA Simulation Suite

Links to my talks on YouTube


This is just a brief sample of my work. To see more or discuss possible collaborations, email me at nir_mandelker -at-

Office: Kohn Hall, University of California Santa Barbara

Santa Barbara, CA, 93106

email: nir_mandelker -at-