Thursday, November 15, 2018

Physical Time and Inner Time

William Blake
We know that physical time goes on regularly, but inner time (our sensation of the passage of time) is very variable. The two times do not have to match. Sometimes, watching at our inner time, a minute can look like hours, while in other cases the hours fly away. An English poet, William Blake, expressed it well in a famous poem:
To see a World in a Grain of Sand 
And a Heaven in a Wild Flower, 
Hold Infinity in the palm of your hand,
And Eternity in an hour
(Auguries of Innocence, 1803?)
There is a long history of literary works, in which a character enters aesthetic or religious ecstasy, or simply falls asleep, and on returning to reality discovers that many years have passed, sometimes centuries. This subgenre (called by scholars sleeper legends) has representatives in many literatures. In Spanish literature, it is reflected in the legend of the monk and the little bird, associated with the monastery of Leire. In this legend, a monk who enters in ecstasy while a bird is singing, discovers upon awakening that three centuries have gone by. Among medieval French lays there is a legend about the knight Guingamor, who arrived in a wonderful city and stayed there for three days, but when he left, he found that three centuries had passed. And in the United States literature we have the famous story by Washington Irving titled Rip van Winkle, whose protagonist falls asleep one night and wakes up 20 years later.

Thursday, November 8, 2018

Fred Saberhagen versus the Turing Test

Alan Turing

In 1950, the English mathematician and chemist Alan Turing tried to define the conditions so that it would be possible to affirm that a machine is capable of thinking like us. For Turing, this will be achieved when the machine is capable of deceiving human beings, making them think that it is one of them. This test is called the imitation game. I have talked about this in a previous post in this blog.
In 1956, Arthur Samuel of IBM built a program to play the game called draughts or checkers. The program kept information about the moves in the games it had played, which was used to modify its future moves (in other words, it learned). In a few years, after playing many games, the program was able to defeat its creator and played reasonably well in official championships.
That same year, during a summer course held in Dartmouth College, John McCarthy and other computer pioneers coined the term artificial intelligence. Getting their hopes too high, they predicted spectacular advances for the next ten years, which did not take place in the time envisaged, but much later. I have also written about this in another post.
In 1963, science fiction writer Fred Saberhagen published the first story of his famous series about the berserkers, autonomous and intelligent space fortresses created by an ancient extraterrestrial civilization to exterminate intelligent life wherever it appears in the galaxy. This story, titled Without a thought, is an answer to the Turing Test and a brake to the unbridled hopes of the inventors of the term artificial intelligence. This is the plot of the story:

Thursday, November 1, 2018

The Hubble-Lemaître Law

Georges Lemaître
Let us look at a little history.
In various places in the sky, but especially in the constellation of Cepheus, where the first case was discovered, there are some stars whose light intensity varies regularly, and therefore are called variable Cepheids. In 1908, the American astronomer Henrietta Swan Leavitt discovered that the period of these stars is linked with their real luminosity: the greater the luminosity, the longer the period. Therefore, by measuring their period, their real luminosity can be deduced.
In 1913, the American astronomer Vesto Melvin Slipher obtained the spectrum of what was then called the Andromeda nebula (the giant galaxy closest to ours) and discovered a blue shift that indicated (according to the Doppler effect) that the nebula moves towards us with a speed of about 300 kilometers per second, much higher than expected. Slipher then studied the light of other spiral nebulae and made the unexpected discovery that most of them, unlike Andromeda, show redshifts, that is, they move away from the solar system with great speed. In fact, he measured speeds above 1000 kilometers per second.
In 1919, the American astronomer Edwin Powell Hubble used the Mount Wilson telescope to photograph several spiral nebulae, including Andromeda, and showed that, actually, they were not nebulae, as had been believed, but huge clusters of stars. From then on they were no longer called nebulae, but galaxies, in honor of our Milky Way, which also belongs to the class of spiral galaxies. Galactos in Greek means milk.

Thursday, October 25, 2018

Measuring the Universal Gravitation Constant

Vertical section of Cavendish balance

In 1798, the English physicist and chemist Henry Cavendish was the first to measure Newton's universal gravitational constant (G) using a spectacularly ingenious method, which has been scarcely improved later. The method was devised by John Michell, who died without being able to carry it out, so Cavendish performed the experiment. In fact, his objective was not to measure the constant, but the mass of the Earth, but the value of the constant could be inferred from the result.
Cavendish’s instrument was a torsion balance from which two identical balls of lead hung. Next to these balls, one on one side and one on the other, hung two much larger lead spheres, 175 kg each, which attracted the first two, producing a slight twist of the balance, which Cavendish could observe by means of a small telescope located outside the enclosure, to avoid observer interference. He thus detected a displacement of about 4 mm, which he measured with a precision of ¼ mm. This allowed him to calculate that the density of the Earth is 5.448 times greater than that of water, from which it is possible to deduce the mass of the Earth and the value of G:
G=6.674×10-11N.m2/kg2
This is the official value, which is known with quite a low accuracy (1 in 10,000), compared with other universal constants.

Thursday, October 18, 2018

Science or philosophy

Pierre Teilhard de Chardin
In a previous post, speaking about intelligence, I mentioned that there are four incompatible philosophical theories that try to explain the phenomenon of human consciousness. I summarize them briefly here:
1.     Reductionist monism or biological functionalism: The mind is completely determined by the brain and by the network of neurons that makes it. The human mind is an epiphenomenon. Freedom of choice is an illusion. We are programmed machines.
2.     Emergent monism: The mind is an emergent evolutionary product with self-organization, which has emerged as a complex system from simpler systems made up by neurons. Some argue that the underlying structures cannot completely determine the evolution of the mental phenomena. These, however, would be able to influence the underlying structures.
3.     Neuro-physiologic dualism: Mind and brain are different, but they are so closely connected that they make up a unit, two complementary and unique states of the same organism.
4.     Metaphysical dualism: Mind and brain are two different realities. The first is spiritual and non-spatial, capable of interacting with the brain, which is a material and spatial substance. Both entities can exist independently of one another, although the body without the mind eventually decomposes.

Thursday, October 11, 2018

Interview with Manuel Alfonseca in a Spanish Newspaper


On February 23, 2018, a Spanish Newspaper (La Opinión, El Correo de Zamora) published this interview with me, performed by Ana Arias, which I am now translating into English. The interview was re-published a few days later (March 10) in the website ReligionEnLibertad (ReligionInFreedom). This is the translation of the interview:

He took an interest in science since he was quite small, as he says. At age 16 he wrote a book of zoology in two volumes that was never published. Anyway, whenever he has to consult information about some little known animal, he consults his book. "And I can find almost everything there," he adds. Now, at 71, he is an honorary professor at the Autonomous University of Madrid.

He believes in science. And also in God. Under the sponsorship of the Caja Rural Foundation and the Science-Religion University Forum held yesterday at the University College, Manuel Alfonseca gave a lecture about The Faith of Contemporary Atheist Scientists.

What is the faith of those scientists?

That God does not exist.

Thursday, October 4, 2018

Cyclic Time and Linear Time

Stephen Hawking
In an article published in 1999, in volume 879 of the Annals of the New York Academy of Sciences, Pier Luigi Luisi speaks about the two traditional models of time that have been considered by traditional philosophy and the mythologies of various historical civilizations. They must not be confused with the two philosophical models originated in the twentieth century, the time A and time B of which I spoke in another post of this blog.
  • Cyclical time, predominant in Asian civilizations and the Greco-Roman world until the Christian world view took root there. The origin of this model is evident, for many natural phenomena are cyclical: sunrise and sunset; the phases of the moon; the annual movements of the stars, synchronized with the seasons and with many biological phenomena...
  • Linear time, prevailing in the three religions who consider themselves descendants of Abraham: Judaism, Christianity and Islam. Linear time can be compared with the course of the life of a living being, which begins at birth, goes on with changes during a certain period, and ends with death.