LOG#056. Gravitational alpha(s).

The topic today is to review a beautiful paper and to discuss its relevance for theoretical physics. The paper is: Comment on the cosmological constant and a gravitational alpha by R.J.Adler. You can read it here: http://arxiv.org/abs/1110.3358 One of the … Continue reading

LOG#052. Chewbacca’s exam.

I found this fun (Spanish) exam about Special Relativity at a Spanish website: Solutions: 1) 2) 3) t=13.6 months = 13 months and 18 days. Calculations: 1) We use the relativistic addition of velocities rule. That is, where u=Millenium Falcon … Continue reading

LOG#049. Ludicrous speed.

We are going to learn about the different notions of velocity that the special theory of relativity provides. The special theory of relativity is a simple wonderful theory, but it comes with many misconceptions due to bad teaching/science divulgation. It … Continue reading

LOG#048. Thomas precession.

LORENTZ TRANSFORMATIONS IN NON-STANDARD FORM Let me begin this post with an uncommon representation of Lorentz transformations in terms of “uncommon matrices”. A Lorentz transformation can be written symbolically, as we have seen before, as the set of linear transformations … Continue reading

I discussed and reviewed the important Cherenkov effect and radiation in the previous post, here: http://www.thespectrumofriemannium.com/?p=3276 Today we are going to study a relatively new effect ( new experimentally speaking, because it was first detected when I was an undergraduate … Continue reading

LOG#046. The Cherenkov effect.

The Cherenkov effect/Cherenkov radiation, sometimes also called Vavilov-Cherenkov radiation, is our topic here in this post. In 1934, P.A. Cherenkov was a post graduate student of S.I.Vavilov. He was investigating the luminescence of uranyl salts under the incidence of gamma … Continue reading

LOG#045. Fake superluminality.

Before becoming apparent superluminal readers, we are going to remember and review some elementary notation and concepts from the relativistic Doppler effect and the starlight aberration we have already studied in this blog. Let us consider and imagine the next … Continue reading

LOG#044. Hydrodynamics and SR.

Relativistic hydrodynamics is a branch of Relativity Theory that faces with fluids and/or molecules (“gases”) moving at relativistic speeds. Today, this area of Special Relativity has been covered with many applications. However, it has not been so since, not so … Continue reading

LOG#043. Tachyons and SR.

“(…)Suppose that someone studying the distribution of population on the Hindustan Peninsula cockshuredly believes that there are no poeple north of the Himalayas, because nobody ca pass throught the mountain ranges! That would be an absurd conclusion. The inhabitants of … Continue reading

LOG#041. Muons and relativity.

QUESTION: Is the time dilation real or is it an artifact of our current theories? There are solid arguments why time dilation is not an apparent effect but a macroscopic measurable effect. Today, we are going to discuss the “reality” … Continue reading