Thursday, March 26, 2026

New Ways to Scam the Unwary

Wallet scam
Spanish film "Los Tramposos"

About 30 years ago, I received my first attempt at the Nigerian scam: a letter from someone unknown to me offering me the chance to participate in a capital evasion operation involving several million dollars, which they proposed depositing into my bank account, offering to share the profits in return. Of course, I didn't reply, although I kept the Nigerian stamp that came with the letter. I suppose that if I had replied, they would have asked for access to my account to make the transfer, and instead, it would have been emptied.

Since then, I've received dozens of similar attempts, since a certain time via email, always originating from some African country. This scam is, in a way, similar to the wallet scam, because in addition to the swindler, the victim also tries to commit fraud; in one case against the supposed mentally challenged person offering the alleged money, in the other against the governments affected by the capital evasion.

Thursday, March 19, 2026

The inconstant constant

Georges Lemaître

In a previous post, The Hubble-Lemaître Law, I explained how Georges Lemaître discovered in 1927 the expansion of the universe, but as he published in a French-language journal, it didn't make a great impact, and for almost a century the discovery was attributed to Edwin Hubble, who published in 1929 in a much more widely circulated English-language journal. This injustice was corrected on October 29, 2018, by the International Astronomical Union, and I echoed the renaming of the law in my post, published three days later in this blog.

The Hubble-Lemaître Law says this: The farther away a galaxy is, the faster it is receding from us. Its recessional velocity is proportional to its distance. The constant of proportionality is called the Hubble constant, which has the dimension of 1/time. In the International System of Units, this dimension would be expressed as seconds⁻¹ or 1/second, but in practice, its definition (speed/distance) is used, with the following units: km/s/Mpc, which means: the increase in the recessional velocity of a galaxy (in km/s) as its distance from us increases (measured in Megaparsecs). One Megaparsec (Mpc) is one million parsecs, and one parsec is equal to 3.2616 light-years.

Thursday, March 12, 2026

A Radio Telescope on the Moon

One of the most interesting radio frequencies for radio telescopes is that emitted by hydrogen atoms when excited by an energy input. Upon returning to its ground state, the atom emits a photon with a frequency of 1.42 gigahertz. This frequency corresponds to the microwave region, which ranges from 300 MHz to 300 GHz. If we focus a radio telescope on a cloud of gas and dust in our galaxy, which is composed mostly of hydrogen, this frequency is easy to detect.

But what happens if we try to detect this frequency in very distant regions of the universe? The expansion of the universe affects these waves by lengthening them (that is, decreasing their frequency), in the same way as the frequency of the cosmic microwave background radiation, which was initially in the visible and infrared regions of the spectrum, is now in the microwave region, with its peak at a frequency of 160.2 GHz.

Thursday, March 5, 2026

A Language Model Trained with Populscience

Since this blog has almost 550 posts, and it's becoming increasingly difficult to find the information you're looking for, my friend Manuel Márquez suggested allowing readers to ask questions to a Language Model (LLM) trained with the blog's content. I thought it was an excellent idea, so I used Google's NotebookLM tool, and you can use it from now on.

One of the features this product offers is the automatic generation of blog posts. To test it, as an experiment, I requested it to generate one, without specifying a particular topic. Of course, I’ll go on writing my posts without the help of the LLM. Before publishing it here, I corrected it manually, because there were many references to my name (which I removed), and also some curious errors, such as making its title 5 Keys to the Universe, 'AI,' and Evolution and then dividing the text into six points. The following is the resulting post, which summarizes the content of this blog in just two pages: