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Video abstract for the article 'Matter and antimatter in the universe ' by Laurent Canetti, Marco Drewes and Mikhail Shaposhnikov (Laurent Canetti et al 2012 New J. Phys. 14 095012). Read the full article in New Journal of Physics at http://iopscience.iop.org/1367-2630/14/9/095012/article. Part of Focus on the Origin of Matter GENERAL SCIENTIFIC SUMMARY Introduction and background. Antimatter has been predicted theoretically, found experimentally and is now commonly used in medical imaging (positron emission tomography). However, no significant traces of antinuclei are found in the world around us. This immediately poses two questions: is this situation representative for the universe, and where does this asymmetry come from? MAIN RESULTS To answer the first question we review the known astrophysical constraints on the existence of antimatter in the observable universe. We conclude that it is almost certain that there are no significant quantities of baryonic antimatter. Antimatter was, however, abundant in the hot primordial plasma that filled the universe after the Big Bang. As long as the temperature was high enough for pair creation to occur, matter and antimatter were present in almost equal amounts, with particles and antiparticles being continuously created and annihilated. The matter that fills the universe today originates from a small excess of particles, one in ten billion, which remained after all other particles and antiparticles had annihilated. WIDER IMPLICATIONS To address the second question, we summarize the possible origins of this primordial asymmetry, focusing on those that may be tested experimentally in the foreseeable future. We discuss the possibility that it was created by the known forces of the standard model of particle physics (SM), concluding that this is very unlikely. Finally, we present a minimal extension of the SM in which the asymmetry is caused by right-handed neutrinos that are also responsible for other unexplained phenomena, namely the observed neutrino oscillations and dark matter.