Entries by Orodruin

Knut Lundmark and the Prehistory of Dark Matter

Look in your standard cosmology textbook (in my case, the closest one at hand is Barbara Ryden’s Introduction to Cosmology) and go to the section which describes experimental discovery of dark matter. Two of the things you will likely find in there are the following pieces of information: The virial theorem applied to the Coma cluster by […]

Associate professor in theoretical astroparticle physics. He did his thesis on phenomenological neutrino physics and is currently also working with different aspects of dark matter as well as physics beyond the Standard Model. Currently teaching courses in mathematical methods for physicists, special relativity, and quantum field theory. A member at Physics Forums since 2014.

A Geometrical View of Time Dilation and the Twin Paradox

Based on the amount of questions we receive on the topic at Physics Forums, there is a lot of confusion in the general public about how time dilation works and the resolution of the twin paradox. More often than not, the confusion is based upon misunderstandings about how time dilation works and an unawareness of […]

Associate professor in theoretical astroparticle physics. He did his thesis on phenomenological neutrino physics and is currently also working with different aspects of dark matter as well as physics beyond the Standard Model. Currently teaching courses in mathematical methods for physicists, special relativity, and quantum field theory. A member at Physics Forums since 2014.

What is relativistic mass and why it is not used much?

It happens that the term relativistic mass is used, in particular in introductory text on special relativity. It should be noted that whether or not to use relativistic mass to a large extent is a matter of convention, convenience, and semantics as long as it is used properly and does not have any impact on […]

Associate professor in theoretical astroparticle physics. He did his thesis on phenomenological neutrino physics and is currently also working with different aspects of dark matter as well as physics beyond the Standard Model. Currently teaching courses in mathematical methods for physicists, special relativity, and quantum field theory. A member at Physics Forums since 2014.

Plus/minus What? How to Interpret Error Bars

People some times find themselves staring at a number with a ± in it when a new physics result is presented. But what does it mean? The aim of this Insight is to give a fast overview of how physicists (and other scientist) tend to present their results in terms of statistics and measurement errors. […]

Associate professor in theoretical astroparticle physics. He did his thesis on phenomenological neutrino physics and is currently also working with different aspects of dark matter as well as physics beyond the Standard Model. Currently teaching courses in mathematical methods for physicists, special relativity, and quantum field theory. A member at Physics Forums since 2014.