Science has progressed, the fundamental questions remain open. In memory of Zvi Yanai

This is how the evening "Conversations with Scientists" emerged, in which scientists who were interviewed in 2000 for Zvi Yanai's book and for educational television were confronted with their position then and now. In the meantime we have discovered evidence for the expansion of the universe, we have solved mathematical puzzles, we have made progress in the study of sleep (but not in solving dreams) and we have not come close to extending life expectancy. The event took place as part of the Israeli Science Day.

Dr. David Harel from the Weizmann Institute is interviewed by Gilad Shenhav from YNET at an evening of appreciation for Zvi Yanai. Photo: Avi Blizovsky
Dr. David Harel from the Weizmann Institute is interviewed by Gilad Shenhav from YNET at an evening of appreciation for Zvi Yanai. Photo: Avi Blizovsky

Many fields interested the late science communicator Zvi Yanai. He was interested in the questions of whether a computer will ever be able to replace man? Will we have eternal life (lecture a lot about telomeres)? He liked to argue with psychologists about the question of whether dreams have a meaning or are they just a random processing operation of the brain? He wanted to know what would happen to the universe, was interested in unsolved issues in mathematics, and of course he liked to challenge philosophers.

On January 26, a panel moderated by Gilad Shenhav from YNET was held as part of the Israeli Science Day, in which the best scientists who spoke with Yanai were guests, trying to understand what has changed in their field since the beginning of the millennium.
The event was attended by: the astrophysicist Prof. Avishai Dekel from the Hebrew University, Zvi Atzmon, a senior lecturer at David Yelin College in Jerusalem; Dr. Micha Ankouri, clinical psychologist, one of the founders of the new Israeli Jungian Society; Prof. David Harel, winner of the Israel Prize for Computer Science, Weizmann Institute of Science; and Prof. Menachem Magidor, professor of mathematics and former president of the Hebrew University.

Astronomy has been flying for the past 14 years

The first guest was Prof. Dekel, who at the time of the interview with Yanai still had open questions regarding dark matter, dark energy (a field then in its infancy) and the mystery of the origin of the universe.
In a conversation with Shenhav, Dekel explained that in all these areas significant developments have been registered in the last 14 years.
As for the dark matter: we know how much and where it is, through the gravitational force it exerts on luminous bodies. We hope to discover the nature of dark matter particles through their "weak" interaction with normal matter (atoms, etc.). This is a difficult technical challenge because the probability of such an interaction is very small.
As for dark energy: we learned that the expansion of the universe is accelerating. The universe will probably expand forever. We hope to better understand the source of dark energy. This requires a better understanding of the Big Bang.
As for the beginning of the universe and the inflationary inflation: last week a polarization was discovered in the cosmic background radiation that indicates gravitational waves (first discovery to predict the theory of general relativity). Such gravitational waves could only have been created when the universe was very, very dense, and suddenly began to expand rapidly, at an inflationary rate. This indicates the event of inflationary inflation in the first fraction of a second of the universe and it confirms the inflation model, which until now was only a theoretical idea, as an integral part of the standard model of the Big Bang.

Life expectancy will be extended but what's the point?

Zvi Atzmon, a senior lecturer at David Yelin College in Jerusalem, was quoted as answering Zvi Yanai's question as to whether there is a limit to life span: "We need to distinguish between the population and individual people - obviously, just as there is variation in height, there is also variation in life span, but stories about people who are 140-160 years old are Unfounded, and it is accepted that the limit is 115-120 years."

On stage in 2014, Atzmon said: "In recent years, especially, there is a lot of talk about extending life expectancy. I spoke with Zvi Yanai about the question of why there is a pause in life and we did not focus on the question of whether it is possible to extend it. I admit that today, if you open a means of communication, what stands out is The leap forward prediction that people will live infinitely longer than today, maybe hundreds of years, personally scares me. The fact that there is an asymptotic limit that can be approached But you can't get over it, it was a great comfort, all the mistakes I made and I made a lot in my life - erase them all and start something else."

"Zvi, too, if I understood him correctly, was not so sorry that there was a limit to this, although he did not emphasize the consolations in that. In terms of science, some people say that life expectancy will be extended. I don't fully understand how. It will be possible to replace organs, grow stem cells and transplant Substitutes. There is one organ where this is not possible - the brain. In the end, the question is whether it will be possible to transplant a body around the brain and kidneys And it is possible to transplant your identity. As far as I know, the brain loses cells and the cells that remain in it lose their abilities, most of the talented people are very successful at a young age and then less so and fade away."

Ivory: "Does evolution require us to have a limited lifespan?"

Atzmon: "Unicellular creatures actually live forever and also a few multicellular creatures, but the majority of the multicellular creatures die at one point or another. Sometimes these are pathetic times - a butterfly that dies of old age after ten days or one-season plants. There are creatures that extend life. Man is endowed With a very long life according to what is expected of him - for example in terms of the number of heartbeats. These days I am taking care of a dog who is in the last days of his life, I have to pick him up, he wets you himself. It's not because something was neglected in him, you see he's coming to the end of his life."

Dream and dissolve

From biology to psychology, do you know how to clearly distinguish when you are asleep and when you are awake? On this issue, Yanai confronted Prof. Peretz Lavi, currently the president of the Technion and for many years headed the sleep research laboratory at the Technion School of Medicine, with Dr. Micha Ankouri, a clinical psychologist, one of the founders of the new Israeli Jungian Society.

In a conversation on stage, Ankuri claimed (this time without his partner Prof. Lavi) that the physiological question that Lavi and his colleagues express that dreaming is only a phenomenon of neurons and that dreaming has no meaning, bothers him "but I did not find the connection between the fields. There is research in the sleep laboratories but I did not find it there The phenomenon of dreaming and not the dream, this is a question that was not resolved then, but it is doubtful whether it will be resolved, what is the connection between the body and the mind, between me My body is a question that did not find its solution 14 years ago nor today."
"I am awake to the mental phenomena that occur in a dream and in the meantime I do not see any contribution from the sleep laboratories, and they do not refer to the story of the dream there, Peretz Lavi says that these are pulses from the brain stem that go to the cortex and there the brain tells us stories. The psychological school holds that dreams have meaning and that we should listen to these stories."

Is the Turing test relevant?

The next guest, Dr. David Harel from the Weizmann Institute, was asked by Yanai in 2000 whether the computer would be able to develop an intelligence close to human intelligence, when Turing, according to the late Yanai, predicted that a computer would be able to pass his test only in 2010 and mentioned the prediction of CEO IBM that five computers will be enough to manage the entire world. Harel then answered him that no one anticipated the internet revolution in which a network of millions of computers would enable the entire revolution (we must not forget that those were the days of the dot.com bubble).

Harel said on stage: "A long time ago, they got rid of the idea that the goal is to make intelligent computers in the general sense. It was precisely in a conversation with Zvi Yanai that he brought up the matter of chess. For example, the software that defeated Kasparov. The ideas developed for this purpose were learned at IBM, not to develop Watson solve a basic problem but any problem. But as I mentioned at the time, this is not an unimpressive achievement. The computer has also been a champion in calculating salaries for 45 years, so what? The idea of ​​the Turing test is a big and broad idea, but this is not the goal of computer science and the world of computers. Some of the ideas developed in Deep Blue were realized with Watson's participation in Jeopardy, but still Watson is not intelligent."

"But what is intelligence? We want to build a device that behaves like me and you. There are things that have such an intelligent aspect, for example the dry and technical concept of programming a computer. You have a box, you want it to do something. The computer scientist's use of programming is specific, but languages Am very technical. I make a leap and use the concept of programming in a different way - when I raise my children, guide the insurance agent or manage my students in the laboratory - I cause To others to do what I want. I sometimes give them instructions in a negative way - do what you want but at 11 you are at home."

"We can say that the computer is intelligent if we are able to program computer systems in the way that we educate or manage and make others do things. You want the computer to learn, to generalize, to be able to have an intelligent conversation about what it has done. No one today thinks that it is possible to pass the Turing test. "

"You need to produce computers that learn that the contexts change dynamically. Three Turing awards that people have received in recent years are related to learning, probability, and another technical topic that I will not go into. The advances in computer science, although a very small part of them are aimed directly at artificial intelligence, are designed to perform all kinds of tasks better, But they are not necessarily more intelligent.

Shanhav: "What about Ray Kurzweil and the singularity theory that holds that in the future a computer will be developed that can produce a smart computer from it?"

"Not that I don't buy what he says, he is not a scientist and certainly not a computer scientist. It reminds me of the story about Descartes, that when I grow up I will be a mathematician and I will have a pencil, paper and a garbage can, and after a year he said I will be a philosopher because I don't need the garbage can either. Both about consciousness and about the singularity - let it go, we are working and progressing even without regard to the fact that a computer will replace the person."

"There is a different type of Turing test - to build a model of a multicellular organism that is so real and so true - for example the worm C. elegans. I want to reach a situation where a computer is used as a model of such a worm and in another room there is a real worm in the laboratory, and that the experts will not be able to distinguish which room the worm is in And what a computer. The Turing test is a test of imitation. It is a kind of Turing test that humanity can aspire to from such a comprehensive and accurate model More important than a computer that you won't be able to tell the difference between a person and a person."

"An animal with a thousand cells will give us a good understanding of life. The blue brain project is as grandiose as the artificial intelligence project. Mimicking the worm is a less grandiose project but will contribute more to the understanding of medicine."


What is the most important discovery to reach in computer science?

Harel: "There are many directions. In my opinion, the most important discoveries in computer science will be in the use of probability in calculation. Could anyone imagine that you want to write an algorithm to bake a cake or give instructions to a child that you introduce uncertainty and ask the computer to flip a coin. Will this improve programming? - Most people will say that it is best to walk in a straight line, but a discovery by several researchers, led by Michael Rabin, showed that the use of probability can result in a smarter execution of The mission. Another important discovery will be the ability to build computers that play animals or communicate with humans. The use of probability and learning are things that are discovered in computer science and it will have uses in everyday life."

Mathematics scares children

Prof. Menachem Magidor, mathematician, former president of the Hebrew University, spoke about the connection between mathematics and its application in economics and the life sciences, since mathematics is universal, the unsolved puzzles and the reasons that cause many in Israel to stay away from the field.

In 2000, Prof. Magidor said to Zvi Yanai that he does not foresee unemployment for mathematicians in the foreseeable future.
On stage, Prof. Magidor was asked what has progressed in mathematics in the last 14 years and he replied: "There have been a series of mathematical discoveries in recent years, but due to the great abstraction required, it is difficult to explain their importance in one word.

"A very famous conjecture solved during the last 14 years is the 150-year-old Poincaré conjecture (the Poincaré conjecture is a conjecture that characterizes the three-dimensional count among all canvases of the same dimension) which was solved by the mathematician Gregory Perlman."

"And also a killer hypothesis that says: "Let's look at the natural numbers. Within them are numbers that are a power of another number. Those numbers that are exact powers are quite rare. Katlan's hypothesis was that there is almost no case where two powers of numbers occur in powers of 1 such as 8 and 9." Katlan's hypothesis was that this is the only case and the mathematician Romani Michalescu about 8-9 years ago proved that Katlan's hypothesis is correct. A private case of it appears in Harlev" C - Rabbi Levi ben Gershom, in the 14th century. that a power of 2 cannot be close in number to a power of 3 and cannot appear except for 8- and 9."

"There are problems similar to Fermat's theorem that are still open and if they are solved, they will make good PR for mathematics. The most prominent of them is the Goldbach hypothesis - every even number is the sum of two prime numbers. What all these problems in number theory have in common is that they are easier to explain to the public because they can be formulated in terms of elementary school."

Shanhav: "There are claims that the economic crisis of 2008 was caused by mathematical models"

"I am not an economist, I have talked with several economists including Nobel Prize winners. There are different explanations, few think that the use of sophisticated mathematical models are the cause of the collapse of the housing market in the USA. Part of the problem stemmed from the fact that the models became so sophisticated and so complex in terms of the mathematical tools they used and the decision makers did not fully understand the tools they used. Those who escaped said they adopted a policy of what they don't understand they don't use. It is desirable that those who are involved in the field also understand it, to the praise of the physicists for example, the theorists understand what they are talking about when they use operators in the Hilbert space."

Shenhav: "You told Zvi Yanai that for you mathematics is absolute. Is that still true?"

Prof. Magidor: "In mathematics we work according to certain rules, axioms, rules of inference, the question why these rules and not other rules is a good question. You can imagine a different mathematics. Maybe it depends on the structure of our brain or it is a cultural matter, but the gut feeling is that mathematics is Absolutely yes. We discover, we don't invent."

Shenhav: "In recent years, alarming figures have been published about a decrease in the number of students approaching matriculation with 5 units in mathematics. Why in the Israel of 2014 is mathematics so frightening to Israeli youth and how can the trend be changed?"

Prof. Magidor: "I don't know if the trouble of many is half consolation. It happens in many countries in the world. I don't think that in the USA mathematics is less scary. It is a combination of several things: First, everything depends on the way math is taught, the quality of the teachers (the people may be good but they don't understand the subject). The CBS data for 2009 is that in the upper division, among teachers who study mathematics, only 22% have a degree in mathematics. In all likelihood, someone whose main subject is not mathematics will not succeed in creating enthusiasm and interest and presenting the beauty of the profession. A second problem is related to the mathematics curriculum, she did not know how to choose the things which are more aesthetically pleasing and practical. The third problem arises from the fact that mathematics requires intellectual effort and in the world In the West there is a tendency to give up intellectual effort for students. A combination of all these things causes a deterioration in the field of mathematics."

Shenhav: "Israel is a powerhouse in mathematics, is there any fear that this will stop?"

Prof. Magidor: "The mathematical superiority of the State of Israel is very noticeable. In the meantime, we received confirmation of this after Elon Lindenstrauss won the Fields Prize - the equivalent of the Nobel Prize in Mathematics. The State of Israel is still at the top of the mathematical world. Losing interest, a smaller part of the public who will be enthusiastic about it and see it as important will throw off On Israel's position in the world of mathematics."

In his memory
Prof. Rafi Melnik, the vice president of the Herzliya Interdisciplinary Center: "We miss the character of Zvi. It is important to remember him and his work and to miss him. A similar field will emerge in society and fill his place."

The director general of the Ministry of Science, Technology and Space, Bina Bar-On: "In one word I would sum it up: original. He was original in everything he took into his hands to handle. Talking about music is like dancing architecture. Before I came here, I wondered how to sketch his character and its many faces. If there was a way to dance architecture, Zvi Yanai would have excelled in it, he knew how to combine different languages ​​into one language."

10 תגובות

  1. Yossi and Eddie

    I tend to agree with you, although it is easy to call the king naked without knowing the details. General relativity
    It has been tested and confirmed by many observations and its classical limit is also the old and familiar Newton's theory of gravitation.
    In order to preserve these established theories, dark matter was proposed. On the other hand, there are theories that do not require dark matter to explain the observations, but each of these theories has problems. The MOND theory proposed by Prof. Muti
    Milgrom of the Weizmann Institute is a phenomenological theory that assumes that Newton's theory breaks down at low accelerations. MOND has no need
    in dark matter to explain the observations but since the theory is not based on first principles but on phenomenology it is difficult to generalize it to relativistic theory (general relativity). The well-known Prof. Beckenstein from the Hebrew University made such a move and created a theory called TeVeS which contains additional scalar vector and tensor fields to the ones we are familiar with, so that in practice to use Ockham's razor the dark matter was replaced with unfamiliar fields, in addition to this the theory suffers from additional failures. Dutch Prof. (one of two twin physicists) Verlinde based gravitation on thermodynamic principles
    Apart from the fact that his theory is problematic, it also does not rule out the existence of the phallic substance. On the market there is also the theory of Prof. Philip Mannheim from the University of Connecticut, which is a theory of conformal grotation, but this theory also has failures with some of which Mannheim was able to fight. For example, one of the arguments against his theory was that it cannot be generalized to a quantum theory, since the quantum vacuum is unstable in the theory, where does this come from? Mannheim bravely faced this question
    As a demonstration that in his theory there is another symmetry that protects it from this problem and that it can also be generalized to a quantum theory. There are several other theories that try to make dark matter disappear, but as I already wrote, all of them, as far as I know, have failures. In my opinion, it would indeed be desirable to focus on the study of alternative theories, but it is still too early to determine that they do describe reality well.

  2. I agree that Ockham's Razor should have ruled out dark energy but it encourages new theories and that may be its role. Rather the derivation of gravity from entropy is consistent with general relativity because the curvature of space results from the accumulation of particles
    in what is known as mass. Dialogue is important. As soon as one of the theories presents unequivocal, observable evidence, the debate will be settled.
    It is perhaps similar to the observation of gravitational waves. It is required to cool detectors to 1E-34 Kelvin, and perform statistics for 3 years. The final result
    was worth:
    A. First confirmation of the swelling model. There are other models. It strengthens him.
    B. First confirmation of my understanding of string theory which is said to be unobservable. Here is an experiment with the power of a trillion trillion LHC.
    third. Reinforcement for the Big Bang.

    That is, the theoretical debate turns into measurement and decision at the end.

  3. Yossi, there is also a 'revised' version of relativity that should agree with the disturbing observations, and it dispenses with the need for the enigmatic innovations of 'dark energy' and 'dark matter'. And there is a version of string theory that reconciles these observations in its own way, and here again there is no need for these enigmatic innovations.
    It seems to me that the principle of Ockham's razor should have tilted the scientific discourse precisely in such directions, or at least in one of them. Instead we get a tireless discourse of arbitrary mystery, in which a kind of deus ex machina is used designed to give an 'ad hoc' explanation of being, as was accepted from primitive science to ether theory. In this discourse there is no scientific 'proof' of the existence of dark energy and dark matter, there are only excuses, tautologies and the assumption of the desired. In the meantime, this is not about science, but about chatter masquerading as science, which came to cover up ignorance.

  4. Agree with Eddie. It is true that the sides of dark matter present more and more evidence for its existence, but the debate has not been decided. There is another theory called modified gravity and there is a Dutch scientist who won the Spinoza Prize (2012?) - who derives gravity from the entropy of particles, and according to this theory it is not necessary that the gravity that becomes a magnitude that results from probability, will maintain a Newtonian gravity characteristic along the entire distance.
    If the correct direction is modified gravity, there is no need for dark matter to explain the appearance of the universe.

  5. I did not understand Prof. Dekel's pretension when he talks about 'dark matter' and 'dark energy' in terms of 'knowledge', and reports on 'important developments' in these areas. The truth is that we know nothing about them - for the time being these are speculations, coming to explain difficulties that arise from observations, also on the theory of relativity in its accepted form - and lead to even bigger bewilderments and questions.

  6. More interesting is how the brain turns information into pain, is it about another dimension, like time and location.
    At the moment there are not even theories.

  7. to the sons of Aaron
    The discussion about faith and divinity was probably left for the rabbinical conference that will be held soon
    On the anniversary of Rabbi Ovadia's death.
    As you do not expect rabbis to deal with science, there is no point in demanding scientists to deal with religion
    These are two different and separate disciplines and even opposite in essence.
    Religion is not looking for proof of anything. It already knows everything. According to the religious belief the laws of the religion
    They are divine laws that express God's will and are therefore a permanent and unquestionable truth.
    Science in its essence, is exactly the opposite. Science expresses and articulates the way in which the human race understands
    the laws of nature at a given time. Science in its essence constantly strives to update the knowledge of the human race
    the laws of nature. Each update of new knowledge constitutes a cancellation and update of the old knowledge.
    True, there are also people who are both scientists and rabbis or religious. However, they also have a separation
    between the two disciplines. They do not involve religious belief in their scientific work on the one hand, and on the other hand they do not
    They use the laws of science to confirm or question their religious beliefs.

    As for your assertion that "..life is not all math and matter" well, a scientist would probably demand evidence from you
    convincing for this statement (not to use the incorrect term "scientific evidence"). A religious person on the other hand
    He would certainly agree with you in your claim that beside mathematics and matter there is also spirit, soul, soul and...
    God.

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