LOG#132. Spacetime foam(II).

The second post in this thread is completely speculative. 1) Suppose that Dark Energy is some kind of “fluid” made of some long wavelength “particles” or “exotic stuff”. 2) How different are those “Dark Energy particles” from the particles we … Continue reading

LOG#128. A chaosmic TSOR returns.

2) I recommend you not to use Internet Explorer. It seems that Explorer does not scale the images very well. Moreover, Explorer seems to be bad working with LaTeX code I use here. So, please, use any other web browser … Continue reading

LOG#123. Basic Neutrinology(VIII).

There are some indirect constraints/bounds on neutrino masses provided by Cosmology. The most important is the one coming from the demand that the energy density of the neutrinos should not be too high, otherwise the Universe would collapse and it … Continue reading

LOG#107. Basic Cosmology (II).

Evolution of the Universe: the scale factor The Universe expands, and its expansion rate is given by the Hubble parameter (not constant in general!) Remark  (I): The Hubble “parameter” is “constant” at the present value (or a given time/cosmological age), … Continue reading

LOG#105. Einstein’s equations.

In 1905,  one of Einstein’s achievements was to establish the theory of Special Relativity from 2 single postulates and correctly deduce their physical consequences (some of them time later).  The essence of Special Relativity, as we have seen, is that  … Continue reading

LOG#057. Naturalness problems.

In this short blog post, I am going to list some of the greatest “naturalness” problems in Physics. It has nothing to do with some delicious natural dishes I like, but there is a natural beauty and sweetness related to … Continue reading

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#050. Why riemannium?

TABLE OF CONTENTS DEDICATORY 1. THE RIEMANN ZETA FUNCTION ζ(s) 2. THE RIEMANN HYPOTHESIS 3. THE HILBERT-POLYA CONJECTURE 4. RANDOM MATRIX THEORY 5. QUANTUM CHAOS AND RIEMANN DYNAMICS 6. THE SPECTRUM OF RIEMANNIUM 7. ζ(s) AND RENORMALIZATION 8. ζ(s) AND … Continue reading