**NEUTRON STARS**

Neutron starsÂ are the extremely dense remnants of massive stars after they die and explode as supernovae. These amazing compact remnants have the strongest magnetic fields in the universe (10^{8Â }-10^{14Â }G), super high densities (~3 x 10^{14 Â }g/cm^{3}), very large frequencies (up toÂ 700 Hz), and very high space velocities (up to 1000 km/s!). However, there are still many puzzles about these compact objects. One such a puzzleÂ is to find out how neutron stars receive an intrinsicÂ “kick” at birth, which originates their large space velocities.Â The research I have done in neutron stars is centered on this specific problem. This is the list of the papers I have written on the subject:

- R. Heras, 2016,Â Magnetorotational instabilities and pulsar kick velocities, N Astron.
**43**, 6 [PDF] - R. Heras, 2013,Â Birth accelerations of neutron stars,Â Proc. IAU., S.
**291**, 399Â [PDF]. - R. Heras, 2012, Pulsars are Born as Magnetars,Â ASP Conf. Ser.
**466**, 253Â Â [PDF]. - R. Heras, 2011,Â The magnetar origin of pulsars,Â arXiv:1104.5060Â [PDF].
- R. Heras, 2011,Â Initial accelerations of pulsars caused by external kicks, arXiv:1103.1929Â [PDF].

**RELATIVITY AND ELECTRODYNAMICS**

My papers on relativity deal with new approaches for deriving the Lorentz transformations as well as the history of these transformations. On the other hand, the paper I have on electrodynamics deals with a review of the Helmholtz theorem as well as several extentions of this theorem.Â

- R. Heras, 2017, Alternative routes to the retarded potentials, Eur. J. Phys. (accepted).
- R. Heras, 2017,Â Four easy routes to the Lorentz transformations:Â addendum to ‘Lorentz transformations and the wave equation,’Â Eur. J. Phys.Â
**38**, 019401**Â**[PDF] - R. Heras, 2016, The Helmholtz theorem and retarded fields, Eur. J. Phys,Â
**37****,**065204 [PDF] - R. Heras, 2016, Lorentz transformations and the wave equation, Eur. J. Phys.Â
**37,Â**025603 [PDF] - R. Heras, 2014,Â Voigtâ€™s transformations in the beginning of the relativistic era,Â arXiv:1411.2559 [PDF]
- R. Heras, 2014,Â The wave equation in the birth of spacetime symmetries,Â arXiv:1407.3425 [PDF]

**PHYSICS TODAY PAPERS**

I have published two papers in Physics Today while still an undergraduate. Both are opinion pieces. The last one being an invited paper with the subject ofÂ how Iâ€™m being taught physics, and especially, how I would like to be taught physics. Â In this commentary, I encourage professors to follow Richard Feynman’s advice to prioritize creative learning in their approach to teaching physics. It is rather unfortunate that physics, which is meant to be an adventure, Â is often taught in a very rigid form!

- R. Heras, 2017,Â Commentary: How to teach me physics: Tradition is not always a virtue,Â Physics Today
**70**, 3, 10 [PDF] (invited paper). - Â R. Heras, 2013,Â Individualism: The legacy of great physicists,Â Commentary & Reviews, Physics Today Online (October).Â Named the most viewed article of 2013 in Physics Todayâ€™s Online Edition. See relatedÂ comment in Scientific American.