Thursday, March 22, 2018

Can there be life without the weak interaction?

Beta and neutron decay

On January 30, 2018, the Science News magazine commented on an article recently published in arXiv which states that in a universe without the weak interaction, life would still be possible. When I read the Science News article, I immediately thought of an objection that could ruin both the thesis of the original article and its popularization. The first thing I did was looking up the original article, to see if my objection was mentioned or denied, but there was not a word about it. Next I detailed my objection in a comment in the web version of the Science News article, but so far no one has answered me. However, I think the objection is quite strong, and unless I am answered satisfactorily, in my opinion these articles are discredited.
According to the standard cosmological model and the standard model of particle physics, there are four fundamental interactions or forces in the universe: gravitation, electromagnetic interaction, and the strong and weak interactions, which regulate the work of atoms and elementary particles. In particular, the weak interaction affects all the elementary particles: leptons and hadrons, unlike the strong interaction, which affects only hadrons.

Thursday, March 15, 2018

Dark energy again

Albert Einstein
In a previous article I mentioned that Einstein introduced a third term in the right side of his cosmological equation, to force this equation to have as solution a stationary cosmos, that would not expand or contract. The attempt was unsuccessful, for such a cosmos would have been in unstable equilibrium, and the smallest variation would have pushed it to either expanding or contracting. The term in question depends on a constant (L, the cosmological constant), which we don’t really know what it is.
Einstein's cosmological equation
For most of the twentieth century, it was assumed that the value of the cosmological constant must be zero. In other words, the third term of the Einstein equation would not exist, wouldn’t be necessary. However, in 1998 it was discovered that the universe seems to be expanding rapidly. At least, this seems to be indicated by the study of supernovas in very distant galaxies, about one billion light-years away from us. To explain this discovery, the cosmological constant term was resurrected, but giving it a sign opposite to that proposed by Einstein, so that rather than the expansion being counteracted, it would be accelerated. This proposal has become the standard cosmological model, in which the first term of the equation, which represents the effect of the mass, currently counts as 31%, while the third, that of the cosmological constant, counts as 69%. In this model, the second is assumed to be zero. I leave apart the question that the mass term does not match, so it has been necessary to assume that there is also a dark matter, that we don’t know what it is.

Thursday, March 8, 2018

One hundred years since The Decline of the West

Oswald Spengler
This year it will mark one century since the publication in 1918 of the first volume of the book The Decline of the West, by Oswald Spengler. The second volume was published five years later, in 1923. This book was the first to raise the idea that our famed Western civilization is in decline. What can we say about it, a hundred years later?
The great historian of the twentieth century, Arnold J. Toynbee, agreed with Spengler on his fundamental idea, although not in the details. For Toynbee, Western civilization collapsed in the twentieth century, when the two world wars proved its inability to face new challenges. Of course, for Toynbee, the collapse of a civilization does not mean its disappearance, it does not even prelude it. We still have ahead - according to him - a few centuries of what Toynbee calls the Universal Empire, linked, however, to a certain cultural stagnation.
The first thing we have to notice is: if Spengler actually managed to detect the decadence of our civilization, it means that the decline had begun much earlier. Evolutionary movements, both biological and cultural, are imperceptible at the beginning. When they become visible, they are quite advanced in their development.

Thursday, March 1, 2018

The problem of human intentionality

A few weeks ago I had in another blog a debate that confronted me with three militant atheists who stood for materialist monism, which holds, among other things, that we are determined by our neurons, that consciousness is an irrelevant epiphenomenon and that free will is an illusion. In another post in this blog I have touched on that topic, mentioning the four philosophical theories that try to explain the conscience, one of which is materialist monism.
This is the argument I offered to defend dualism against materialistic monism:
Let’s tackle the problem of human intentionality. When I say: I'm going to lend money to the bank, so I’ll be paid interest, I’m saying that the reason why I’ll lend money to the bank is to get interest. This is the kind of cause that Aristotle called a final cause, because it is the goal toward which my action is directed, something that is located in the future. On the other hand, materialist monism says that the only cause of our actions is in the electric discharges of our neurons. This is what Aristotle called an efficient cause. Therefore, to explain the same phenomenon (my lending money to the bank), we are suggested two different causes: my intention and the sparks in my neurons, this second located in the present, the first in the future. Is this possible?

Wednesday, February 21, 2018

Chaos and catastrophes

Michael Crichton's novel Jurassic Park is an allegation against the unreasonable use of science. In the words of Dr. Ian Malcolm, one of the characters in the book:
Scientists are actually preoccupied with accomplishment. So they are focused on whether they can do something. They never stop to ask if they should do something. They conveniently define such considerations as pointless. If they don't do it, someone else will. Discovery, they believe, is inevitable. So they just try to do it first. That's the ga me in science. Even pure scientific discovery is an aggressive, penetrative act... Discovery is always a rape of the natural world. Always.
This problem arises especially in the scientific field that serves as the basis for Crichton's novel, genetic engineering, which poses many important ethical problems. There are many things that we can already do, or are close to achieving, but should they be done? I will mention a few:

Thursday, February 15, 2018

The star of Bethlehem

Giotto - Adoration of the Magi
Chapter 2 of St. Matthew’s Gospel begins with these words:
After Jesus was born in Bethlehem in Judea, during the time of King Herod, Magi from the east came to Jerusalem and asked, “Where is the one who has been born king of the Jews? We saw his star when it rose and have come to worship him.”
First, a few considerations about this text:
  • Magi is a term with different meanings. Strictly speaking, it was applied to the priests of Mazdayasna, the religion of Zoroaster. Zoroastrian magi were frequently devoted to astrology (the name then given to the science we now call astronomy). So, in a broad sense, the word magi could be applied to anyone who worked in that science. The New Testament does not say that they were kings. That is a later tradition.
  • It will be noted that the text does not say that they were three. They must be at least two, since the term is plural, but later thinkers have discussed whether they were two, three, or even six. The three magi is also a later tradition.
  • It is explicitly stated that King Herod was alive. When did Herod die? Since Emil Schürer (1896) it has been assumed that he died in the year 750 ab Urbe condita (a.U.c., since the founding of Rome), which corresponds to year 4 b.C.e. (before the Christian era). From this, many historians deduced that Jesus Christ must have been born before that date. Therefore Dionysius Exiguus, author of the idea of ​​numbering the years since the birth of Christ, would have made a mistake in assigning the year 754 a.U.c. to his birth. But some modern historians think that Herod could have died in the year 753 a.U.c. (year 1 b.C.e.), and that his sons pushed back the beginning of their own reign, thus causing the discrepancy and leading Emil Schürer to a wrong conclusion. Consequently, the most probable date for the birth of Christ would be between the year 7 b.C.e. and the year 2 b.C.e.

Thursday, February 8, 2018

Scientific questions in Blade Runner

Philip K. Dick's sci-fi novel Do androids dream with electric sheep? was published in 1968 and quickly became a cult book, with many supporters and not a few detractors, among them myself. Fourteen years after its publication, its adaptation to the cinema with the title Blade Runner multiplied the number of its supporters.
In another post in this blog I mentioned that, in my opinion, the film is much better than the novel. When I read the latter, I did not like it. The time has come to explain why. This is the plot:
In a future world, in the year 2019, the advance of technology makes it possible to build androids (replicants in the film), beings of appearance identical to a human being, endowed with intelligence, but who have not been born in the usual way; they have been built. This future society tries to keep replicants segregated, so that they won’t mix with traditional humans. To achieve this, a new profession is invented: the killer of replicants who try to pass themselves off as humans. As soon as they detect a replicant doing this, the destroyer pursues and kills the replicant in cold blood, without a trial.
The above summary can be applied almost equally to the novel and to the film. So far, the argument is interesting, original and attractive. Why then did I say that I did not like the novel, but did like the movie?