Thursday, August 28, 2014

Cultural evolution and biological evolution


Cultural and biological evolution are similar because natural selection acts in both cases. Cultural productions compete against one another and many become extinct. As in the case of living beings, not always the best win. Chance has an influence. In this way, for instance, Windows-95 threw OS-2 out of the market, even though at that time the second operating system was better. Another example is the result of the war between the three competing models of video recording: Betamax, 2000 and VHS.
In the same way that living beings exhibit genetic variability (many varieties of the same gene co-existing in the same population), there is also a cultural variability, represented by the co-existence of old and new makes and models of the same product. At times of big change in the environment (we are just now experiencing one) a cultural product may escape extinction thanks to its variability, by combining versions and producing something new, better adapted to the new circumstances.
The parallel is quite impressive. What we call a species in the biological world, may be considered similar to a civilization. But there are also deep differences between both phenomena.
While studies about biological evolution get back in time to one century and a half ago, those about cultural evolution are more recent: not even half a century. One of its pioneers, Richard Dawkins (who invented the term meme for cultural elements equivalent to genes) made the mistake of considering biological and cultural evolution as identical processes, forgetting their differences. Cultural evolution is almost exclusively typical of man and exhibits new phenomena, emergent features that make it quite different from biological evolution:

Monday, August 25, 2014

Solution to the time machine problem

Answer to the problem posed in a previouspost, on August 18th 2014:

This is what happened in the second scenario: 

At 16:01, the original Max traveled to the future in the second time machine. When he arrived, he found there the second Max waiting for him with the first time machine. He moved to the other machine and traveled back to the past, arriving at 15:59. After changing machines again, he traveled to the future in the original time machine. He never returned.

Only these two scenarios are possible. Any other you may try to build would be inconsistent (try and you will see).

Consequences: 

It is easy to see that the world line for the machine is the same in both scenarios. What changes is the traveler’s world line.

1.            In scenario 1, the traveler does not change machines either in the present or in the future.
2.            In scenario 2, the traveler changes machines both in the present and in the future.

Therefore, if time travel to the past were possible, the traveler would not be free. What he does in the present logically determines what he must do in the future. If he changes machines now, he must change in the future. If he doesn’t, he mustn’t.

Conclusion: 

Nobody doubts that a human being is free to take an elementary decision such as changing chairs or not. 


Therefore time travel towards the past must be impossible.

Thematic thread on Time: Previous Next
Manuel Alfonseca

Thursday, August 21, 2014

This is what science says about human life

With respect to current discussions about abortion, protection of life, and the rights of the pregnant woman, I think it timely to recall the scientific consensus about human life:

·        The life of every living being generated by means of sexual reproduction begins with the fertilization of the female by the male gamete, i.e. with the formation of the zygote. That is the point in time when a new being appears, of the same species as its parents, whose genetic endowment (its DNA) is different from that of its parents and any other living being of the same species, except for identical twins. This new living being will keep its genetic endowment until its death. This is the reason why the eggs of sea turtles and other endangered species are protected, because they are individuals of those species.
·        In every species of living beings who do not go through metamorphosis (including all reptiles, birds and mammals, and of course man) there is no sharp change in their development from the zygote to death. The different phases we use to make out (embryo, fetus, neonate, child, teenage, adult and old) are arbitrary, without any discontinuities. Not even the birth is anatomically discontinuous (it consists in cutting a blood vessel; physiologically it has other effects). There is no doubt that in all those phases, from the first to the last, the same individual is involved.
·        In every placental mammal (including man), the first phase of the life of the new individual takes place inside the body of the mother. Pregnancy is equivalent and replaces development inside the egg, which in reptiles and birds takes place outside the mother’s body. In both cases, maternity begins in fertilization, not in birth, whose equivalent is the rupture of the egg shell. A woman is a mother from the moment she becomes pregnant.

Monday, August 18, 2014

The time machine problem

I am posing here a problem with interesting consequences about the (im)possibility of time travel. I'll pose the problem by means of two science-fiction vignettes. If you decide to try your hand at solving it, you can describe your solution in a comment to this blog post. Next week I'll explain the solution and its consequences.

First vignette

At 15:55, Max told me:
“I have just invented a time machine. Do you want to see it?”
Of course, I accepted. 

  • At 15:58, Max and I entered the room where the machine was. It looked like a simple metal chair. The machinery seemed to be located under the seat.
  • At 15:59, while Max and I looked at the machine from the room’s door, a second exact copy of it suddenly appeared, just near the machine. In the second machine was seated an exact copy of Max. Amazed, Max and I looked at him.
  • At 16:00, the original Max crossed the room, sat on the original machine, pressed a control and disappeared towards the future. The copy of Max, still sitting on the copy of the machine, observed attentively what he was doing.
  • At 16:01, the copy of Max pressed a control in the copy of the machine and disappeared towards the future. Max and the machine never returned.


After thinking for some time, I deduced what had happened. At 16:00, Max travelled to the future in his time machine, but when he arrived he travelled back to the past, arriving at 15:59. He watched the original Max leaving on the original time machine at 16:00, went again to the future at 16:01 and never returned.

In the figure, the blue line represents Max, while the red broken line is the time machine.

Second vignette 


At 15:55, Max told me:
“I have just invented a time machine. Do you want to see it?”
Of course, I accepted. 

  • At 15:58, Max and I entered the room where the machine was. It looked like a simple metal chair. The machinery seemed to be located under the seat.
  • At 15:59, while Max and I looked at the machine from the room’s door, a second exact copy of it suddenly appeared, just near the machine. In the second machine was seated an exact copy of Max. Amazed, Max and I looked at him.
  • At 16:00, the copy of Max stood up, went to the original machine, sat on it, pressed a control and disappeared towards the future. The original Max, near me, observed attentively what he was doing.
  • At 16:01, the original Max crossed the room, sat on the copy of the machine, pressed a control and disappeared towards the future. Max and the machine never returned.
Please, kind reader, can you help me find out what had happened in this second scenario?


See solution
See Spanish version
Thematic thread on Time: Preceding Next
Manuel Alfonseca

Thursday, August 14, 2014

The God Particle

Peter Higgs
With the discovery of Higgs boson, two years ago, the media and a few scientists have presented the discovery as the final completion of the standard theory of particle physics, in such a way that we now know everything and do not need God. Hence the nickname given to Higgs boson, the God particle, a name, by the way, that Higgs does not like.

The discovery of a particle whose existence was predicted nearly a half century ago is a spectacular success of the standard theory, comparable to the success achieved in 1846 by Newton’s theory of universal gravitation with the discovery of Neptune, whose existence had been predicted by Le Verrier and Adams. Then it was also said that we now know everything

Urbain Le Verrier
True, there was still a loose end, a very small discrepancy of just 43 seconds of arc per century in the precession of the orbit of Mercury. Le Verrier tried to repeat his success and predicted that this discrepancy was due to an unknown planet between Mercury and the Sun. He even gave it a name: Vulcan. For 60 years, many astronomers tried to find the mysterious planet in vain, for the problem in this case was in Newton’s theory, which eventually came to be just a first approximation of a new better theory that explained the discrepancy: Einstein's general relativity.

Could something similar happen to the standard theory of particle physics? Will its great success be followed by its first failure? Are there any loose ends still remaining in the theory?

The answer to the last question must be affirmative. The standard theory of particle physics has the following outstanding issues:

Wednesday, August 13, 2014

What is man?

Since about one century ago, after the consolidation of evolutionist theories, and getting from them philosophical consequences without a scientific basis, many biologists assert that man is an animal like any other, one between millions of species of living beings, and it would be impossible to set criteria to help us decide if one species is more advanced or more important than any other.

Is this true? I think it is evident that those criteria do exist, that we should not be denied the ability to compare and judge, two capabilities that have made our technological advances possible. I’ll mention just two of those criteria:

·         The origin of life, about 4000 million years ago, did not have an immediately observable impact on the physical aspect of the earth. Just a few changes in the water hue, or the apparition of cyanobacteria reefs. Nonetheless, the action of life on Earth continued slowly and culminated about 1000 million years ago in a new composition of the atmosphere with about 20 percent oxygen, which made respiration possible.
Multi-cellular living beings changed deeply the physical appearance of the Earth: the dominant color of continents turned green. Of the three kingdoms at this level of life, plant produced the largest impact, while fungi and animals are practically imperceptible from outer space.
In the last centuries, the situation has changed: for good or evil, the human species by itself has modified the aspect of our planet. The surface of the tropical forests is decreasing; many living species are in danger; holes in the ozonosphere turn up; the night sky is full of light; and, for the first time in history, the Earth has become an emitter of low frequency electromagnetic waves (radio and microwave), which makes our existence detectable by hypothetical extraterrestrial intelligences. A single species has done this in a terrifically short time, compared to the history of the Earth.
·         On the other hand, in very recent years, most members of the human species have become able to access a huge amount of informationan ever growing amount, over one quintillion bits (1018). Compare this figure with the information accessed by the members of any other species, from bacteria to chimpanzees: between one million and 200 million bits, seven to twelve orders of magnitude below ours. The information at our disposal may already be higher than the total amount of information accumulated by all the hundred million species of living beings considered to have existed from the origin of life, assuming that it makes sense to add it all together.

Is man a species like any other? No. For some biologists, biological classifications should give man at least the rank of a kingdom of nature, for it is very different to all the other species. Man was considered different during most of the history of mankind, until some biologists in the twentieth century started their continuous and surreptitious work of undermining human dignity.

Spanish version of this article
Thematic thread on What Is Man: Next


Manuel Alfonseca

Tuesday, August 12, 2014

The Dawkins Delusion

Richard Dawkins
This is my analysis of Richard Dawkins book, The God Delusion (2006). I'll start by signaling a couple of inconsistencies. There are many more, but detailing all would require a book size.
·         In chapter 3, Dawkins debunks the theistic argument of the admired religious scientists (how can you not believe in God, when so many admired scientists did believe?). I agree with him, this argument has no weight. But then, why does he use once and again the argument of the admired atheistic scientists? One half of chapter 1 is dedicated to tell us that Einstein did not believe in a personal God. In chapter 2 he asserts, more than once, that most of the founding fathers of the United States were atheists, although few of them dared to confess it publicly. (I suppose that's why they printed In God we trust in their paper currency). He also says that Thomas Huxley, who invented the word agnostic to classify himself, must have really been an atheist, although he never made it public, submitting to the demands of his time. He admits that Newton... did indeed claim to be religious. So did almost everybody [in his time]. A little more, and he would have also said that Newton was another hidden atheist.

The Grand Design

In 2010, the media gave a lot of coverage to a book on popular science by Stephen Hawking and L.Mlodinow, The Grand Design. I think it is time to make a few comments, which I am going to introduce by means of quotations of the book:
·         Philosophy is dead… Scientists have become the bearers of the torch of discovery in our quest for knowledge.
These words appear at the beginning of the first chapter. Although most of the book is just popular science, or history of science, it is ironical that the only original contribution (model-dependent realism) is purely philosophical.
·         Objective reality is unknowable, therefore we cannot assume it exists... Only the results of observations and the model we build to explain them exist... Every model is valid (real) in its own field of application... Two models with the same explaining power are equally valid... Ptolemy's model is as valid as Copernicus's... Their only difference is the fact that the second is simpler than the first.
The preceding text is not a literal quotation, but a summarized paraphrase of chapter 3, which describes model-dependent realism, the original contribution of the book (with Berkeley's permission). The authors forget that Copernicanism predicted correctly the stellar parallax, which cannot be explained in Ptolemy's. In the same chapter, Hawking and Mlodinow discard the steady state cosmological theory because it is unable to explain certain observations on the universe. Shouldn't they do the same with Ptolemy's?