## LOG#212. Understanding gravity(II).

Hi, there! In the previous blog post and log, we introduced the high energy stringy part of the 4-point (particle!) tree approximation amplitude for the graviton scattering in type (II) superstrings (1)   This “simple” formula gives no negative probability … Continue reading

## LOG#211. Understanding gravity (I).

Hi, everywhere! Have you missed me? A little short thread begins. This thread is based on some Nima’s talk on the understanding on gravity. Do we understand gravity? Classically, yes. Quantumly, it is not so easy. String theory is the … Continue reading

## LOG#209. A cosmic link with a non-trivial zeta zero?

Some weeks ago, the Riemann zeta function and the Riemann hypothesis were again in the news. Sir Michael Atiyah proposed a (wrong) failed proof of the Riemann hypothesis. My blog has an history of being controversial from time to time. … Continue reading

## LOG#194. On minimons, maximons and darkons.

If you believe in both, relativity AND quantum mechanics, something that I presume you do due to experimental support, you are driven to admit that the speed of light is the maximal velocity (at least, the maximal 1-speed, in single … Continue reading

## LOG#189. Fundamental challenges.

The marriage between gravity and quantum mechanics is “complicated”. The best physicists and brightest minds have tried, but only with partial success. String/superstring theory, now M-theory, is a curious story. The another story is canonical quantum gravity, or loop quantum … Continue reading

## LOG#186. Polylogarithmic condensates.

Today, I return to my best friends. The polylogs! Are you ready for polylog wars? The polylogarithm can be represented by the next integral: (1)   As you know, if you follow my blog, you have         … Continue reading

## LOG#178. Divergent sums: The Number awakens!

Are you divergent? Divergences are usually sums or results you would consider “infinite” or “ill-defined” (unexistent) in normal terms. But don’t be afraid. You can learn to “regularize” a divergent series or sum. Really? Oh, yes!Beyond faction of a well-known … Continue reading

## LOG#165. Rogers-Ramanujan identities.

There are some cool identities, very well known to mathematicians and some theoretical physicists or chemists, related with Ramanujan. They are commonly referred as Rogers-Ramanujan identities (Rogers, 1894; Ramanujan 1913,1917 and Rogers and Ramanujan, 1919). They are related to some … Continue reading

## LOG#164. Theta functions.

Hi, there! We are going to explore more mathematical objects in this post. Today, the objects to study are theta functions. A prototype is the Jacobi theta function: (1)   where and . It satisfies the functional equation (2)   … Continue reading

## LOG#163. Q-stuff and wonderful functions.

In this blog post I am going to define and talk about some interesting objects. They are commonly referred as q-objects in general. The q-Pochhammer symbol is the next product: (1)   with . The infinite product extension is also … Continue reading