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Thematic Circle D : Research for the Universe – a challenge for future generations

Saturday, 5th September                    Σάββατο, 5 Σεπτεμβρίου 2015

Thematic Circle D : Research for the Universe – a challenge for future generations

Chairmen : Spyros Mercouris & Konstantinos Zaimis

15.00 – 17.00

Dionyssis Simopoulos, former director of the Eugenides Foundation Planetarium

Stavros Katsanevas, Professor / Director Astroparticule et Cosmologie (APC), France

Wang Yifang, Institute of High Energy Physics, Chinese Academy of Sciences

(SKYPE connection)

17.00 Break

17.15 – 18.00 Discussion

18.00 – 19.00 Conclusions and Resolutions

20.15 Dinner


Δ Θεματικός Κύκλος « Έρευνα στο Σύμπαν Μια πρόκληση για το μέλλον»

Πρόεδροι :Σπύρος Μερκούρης και Κωνσταντίνος Ζαίμης

15.00 – 17.00

ΔιονύσηςΣιμόπουλος, τέωςδιευθυντής of the Eugenides Foundation Planetarium

Σταύρος Κατσανέβας, Καθηγητής Διευθυντής του AstroparticuleetCosmologie (APC), Γαλλίας

Wang Yifang, Institute of High Energy Physics, Chinese Academy of Sciences

(σύνδεση με Πεκίνο μέσω SKYPE)

17.00 -18.00 Ερωτήσεις – Συμπεράσματα – Αποφάσεις

20.00 Δείπνο




Thematic Circle D : Research for the Universe – a challenge for future generations

Chairmen : Spyros Mercouris & Konstantinos Zaimis

15.00 – 17.00

The first speaker of the final session was introduced. Dionyssis Simopoulos, former director of the Eugenides Foundation Planetarium worked at space planetarium, was there until the beginning of the seventies., and then invited to come to Greece to head the Eugenides Foundation Planetarium. An important institution scientifically and educationally – since its establishment intended to impart knowledge to the general public and to make this knowledge more accessible through exhibitions, publications. When he took over, he altered many things and quadrupled the attendance of people. Went also one of the first digital. Very fortunate to have him as a speaker. We started from ancient times and move now into the future.


Dionyssis Simopoulos

Title: The universe of stars – voyage with no end

Every time when I am to speak on this sacred earth, of course, I come from a village near Olympia and which is called Gryllos and which is the only place with special links. Xenophon was exiled from Athens to this place but I will not talk about my village. Rather I will want to talk about the universe.

This vast universe has been expanding from minimum to billion light years. The latter acts as measure for distance. What we see is basically memory: the distance are enormous so what we see is as it was 25 light years ago.

Even our sun which is 150 Billion km away, needs enormous speed to reach us. The sun may have been destroyed but we will not realize it right away.

Andromeda Galaxy we see how it was many years ago, and the latest discovery is 13.2 light years away.

The relationship of man to the sky is a curious one. Only when man started to stand upright, he asked what is it what I see, what are these lights up in the sky?

Aristotle stated that it is in the nature of man who wants to learn. So this effort is not new. Learning is a voyage Therefore going out into the universe is a voyage with no end.

Galileo used in 1609 a small telescope and with which he ventured out into the universe. Today telescopes are huge. They allow us what we see within a small window of all the radiation reaching us.

Radio telescope has opened up still a further information slot. It lets us realize things which we could not see. Over the past fifty years this research has expanded so that the universe can be seen differently. With space crafts giving us new information, again it alters perception of the Cosmos. There exists an electric magnetic spectrum. When compared with a portion of a building, it means not everything reaches us. So we have protection from these rays. If we could collect all information into one volume, in order for us to record all the information, we would need a huge library.

Many say photos are good, but then still other information is good. Thanks to modern astronomy and due to our application of knowledge, we have now materials made available by space exploration. This type of activity helps us a lot to understand the universe. If you look at other applications even in farming you use technology. And in all these activities in space play an important role.

Alone the Asteroids which may be dangerous for our survival are of interest.

The sun we call the day star. If only we could harness much more than what we do today, for every second which elapses, the sun is emitting so much energy. Greece loses so much energy even if it could make a lot of money out of it.

Our milky way galaxy consists of over 200 billion stars. If you would want to count the stars, you would need seven and half thousand years to count them. It might be the solution for the debt Greece owes. If we convert this debt into Euros to pay back, it would take us 10 000 years to pay all that back. The same with counting the stars.

When you have a star being born, then you have two forces acting. There is gravity on the outer layers and which pushes inward, while inwards you have forces created out of the inward pushing. These are nuclear reactions. The sun has a balance between these two forces, and it is the main sequence of star clusters. Interestingly enough, their initial mass at birth determines their destiny. From then on the star develops until it dies.

The death of stars depends on the quantity of the material they contain. At the end of their life cycle there can be observed a swelling of the star in its effort to continue to exist. It becomes a red giant replica of the nuclear explosions inside and then you have an implosion on the outer surface. It gives us an idea of what will happen to the earth when it dies.

The earth is a dwarf in comparison to giant stars. All the time hydrogen is being transformed into helium, a mixture of carbon and oxygen. A lot of conversions take place until you come to the 26 elements. Iron tries to convert itself but instead of creating energy, it absorbs energy. So what happens in seconds on the external layer is pressed inwards and then collapses. You have such a pressure. In the end what remains in the nuclear centre and which is called Pulsars, is that you have the neutron stars. They spin around their own axis every second hundred of times. These are objects which have been discovered and researched into.

That leads us to the supernova. (Note: A supernova is a stellar explosion that briefly outshines an entire galaxy, radiating as much energy as the Sun or any ordinary star is expected to emit over its entire life span, before fading from view over several weeks or months.) When they collapse instead of converting to a neutron star, they convert into a black hole. It is a weird object which does not omit any radiation.

11 Km per second has to move the space craft to get out of the gravity of the earth.

Black hole implies that radiation cannot escape.

The death of stars is not simply an end but rather it is a start of something new with materials being spread out in the universe.

If you look at the human body, it is made up of six elements. Consists of 7 x 18 -27 atoms of which 62% is hydrogen which existed long time ago.

So you are 13.8 billion years old.

This is our galaxy which makes up our universe. In the past fifty years we have discovered something else. We discovered there is matter about which we know very little and therefore we call it dark matter.

Former energy – dark energy: not known what is made of – makes the universe to expand over the past six billion years. But then the universe will have dispersed so much, that we will see only our neighbouring stars.

Dark matter accounts right for 25.8%

Science frees us from the anthropocentric ideas. Now we know how small is our earth and we are on the shores of the universe. We wonder what is out there?

When the birth of the earth took place, it was a violent birth. There is no such thing as harmony.

Chairman: Introduces Stavros Katsanevas, Professor / Director Astroparticule et Cosmologie (APC), France, one of the Greek scientists with international reputation. He is Director of the Laboratory Astroparticle Physics and Cosmology at Universite Paris 7. He has 200 graduate students under him, and is involved in numerous European research projects.

Stavros Katsanevas

Title: Connecting scales: from the infinitively large to the infinitively small

We will talk about connecting scale – this is a golden ladder: connecting various scales. There exist several questions along those lines as:

  1. are the particles / causes immanent or transcendent?

  2. is this cosmos eternal or was there a 'beginning'?

  3. what is the nature of space and time?

  4. what are the elements that constitute the cosmos?

  5. what are the principles of change and permanence?

  6. is the cosmos we are living in unique?

  7. what is the place of man in the cosmos?

  8. Will the cosmos end and how?



Cosmos, genealogy of the concept

Homer in Book XIV of Iliad describes Hera. This he sent to Andrei Linde (Russian-American theoretical physicist) who replied by stating such poetic representation is an amazing exerpt. It entails a sex appeal which makes him want to inquire further into this subject matter i.e. the cosmos.

Pythagoras used for the first time the concept to describe the totality of things. It relates to the incident of the 5 hammers. It is when he realized that there was harmony and therefore reality is a number. This discovery meant to him when I am happy in my soul then celestial harmonies have been there to show the connection between cosmos and the soul. Thinks all stars follow a pattern and therefore there is harmony. That started a search for celestial harmony.

But is there really such an order of things, in particular, if randomness of things is much more factual? For instance, Heraclitus state that the random pile of things is the most beautiful cosmos.

Cosmos, genealogy of the concept III

K. Papaionannou, philosopher stated that harmony allows everyone to become what they are. If this means to become humane, it would a need for a certain freedom expressed best by assuming everything is in order if only the small village could take their course. Regardless of refuges seeking safety elswhere, then the perception was if the universe is the road and shall influence the decisions taken - this one finds in the Chinese culture – then the social world according to Tchoang Tzeu shows a slow agglomeration. (Note by editor: It would make harmonious relationships be determined by the universe.)

Cosmos and the elements

Came along Timeus and de Caelo to discuss the five elements:

1. earth 2. water 3. air 4. fire 5. ice vapour

According to Plato, these elements are a part of fundamental particles forming primordial triangles, so then theories of change can be conceived to decribe phase transitions as the emergence of opposites. There were brought about as well theories of permanence (conservation).

The first modern Cosmologies were Galileo and Newton. They spoke of gravitational space. There is an equation: law of gravity – action at a distance. Thus Newton would say that “it is inconceivable that inanimate brute matter should without the mediation of something else which is not material, operation upon and affect other matter without mutual contact.” This is called in the language of physics a 'hypotheses non figurative'.

An interesting observation was made, namely that gravity can predict the invisible.

More and more the question was asked why darkness? There was a need for a new theory which Newton tried first to answer, but then came along Einstein with the relativity theory. Out of this follows that gravity is the stage not the actor. To equate mass and space, the geometry of space and time has to be determined by its content. That means energy relates to mass and vice versa.

But once it was discovered that the universe is expanding, Einstein admitted he had made a blunder in his assumptions and theoretical perception of the universe.

Three possibilites exist with regards to how the Cosmos can be perceived:

Spherical                                              hyperbolic                                          or flat (Euclidean)

Earth is always our only observatory, our empire of the middle. The past is not behind us, but surrounds us. Thus everything becomes a Search for Times lost – Proust

Discovery bumped into a wall. It was not an impenetrable wall but a plasma wall consisting of both visible / invisible matter or particles.

Hubble discovered in 1930 that the universe is expanding, and yes, there is a beginning to our earth. Two premises relate to that plausible explanation. The beginning is not an explosion from a single point while at the same time the distance between all galaxies increases so that space is created between them.

Dyson reasoned if the universe was static and eternal and not in expansion, there would be no structrure in the universe, or else every structure would be destroyed (entropy).

Penzias and Wilson Nobel  explored the plasma by means of cosmological microwave. In so doing, they came across radio waves which have the same temperature. They discovered this very wall in 1965. Wishing to know more about the creation of nuclear elements, they sai to themselves, lets get to the temperature inside the sun. For there are the first nuclear elements made up of Deuterium and helium,

We know matter (quarks, leptos, neutrinos) is only a small part of the mass of the universe (cyclical bastards). By redefining mass being visible and invisible, something else can be perceived. For when light goes in the hole then we have focus on a phenomenon since then we can assume to have a galaxy behind the wall. Hence we see what mass is between us and that galaxy.

Wilson discovered the uniformity of the radio waves and noted that there was no perfect order, only areas of higher and lower density. These were seeds or clusters so that where we had the first clusters of mass, we could distinguish the yellow ones as aving higher density, while the blue ones had a lower density.

Other aspects are theFluctuations otherwise perceived as the cosmological microwave. They show that the big bang was a violent change and out of it a number of harmonics were produced. These gravitational waves – waves in the plasma have almost the speed of sound – make the music of the sky.They consists of a thousand waves. It prompted the harmonic analysis of the fluctuations of the primordial plasma. One can imagine the Earth to be like a bubble in a glass and which is formed by a cluster of galaxy. The fluctuations result out of the formation of structures brought about by agravitational collapse. Here reference to dark matter does not suffice as an explanation.Tthere is needed regulation (feedback) from violent phenomena and this is a particle physics uses to help us study what made our universe. It consists of high energy cosmic rays which we measure under sea by using various senses to observe these gravitational waves.

At the beginning of the 21century, we know about macro physics but not micro physics; like wise it is the same case in economics in not knowing much about consumer behaviour at macro level.

In quantum mechanics, we refer to the particle and to wave unification in the subatomic world. There can applied certain distinctions:

The quantum nature of the vacuum is the fundamental state of energy. It comes close to the emptiness of a vase or of a vacuum which brings about quantum creativity. It is an argument against Empedocles and his definition of matter.

By using a standard model of matter and interactions, can we really go beyond the horizon of the visible? To see, we rely on physics of the instant, otherwise known as 'phase transition'.

Furthermore, we use Higgs' mechanism to explain the following phenomenon: if you have high temperature, then everything is symmetric and particles are massless, but when temperatures are regularity lower, then everything is asymmetric and thereby this order of things gives mass to the particles.

So we use theory as guidance, but in order to have a coherent theory, we must keep in mind what a Thracian girl said to Thales when he descended in a well: "Look up in the stars and you do not need to watch what is under your feet!"

Hence we view matter in terms of anti matter, and seek to understand what brings about a change in the symmetry of things. We can we come closer to what we seek to describe and to understand by using the Planck scale. At the same time, we have the Hawkings theory which states that there is no single way for us to look at the same universe. Rather we look only at a part. Hence our question is constnatly, if there is something else? Some people claim there are multiple universes with different laws. One begins to wonder all the time about the universe.

Anaximander, in his first philosophical treatise now existing only as a fragment, states tht this is neither water but a different matter which is a prior (infinite or formless) as material cause of things.

Yi Jing was even more modern in his approach and stated two metaphorical opposites within the unity of phenomenon:

                                     - large is the capacity of capacity

                                     - clouds pass, rain spreads

So Dionyssis Simopoulos is right when he speaks about the voyage into the universe as being without an end. We have, of course, poets like Dante, Eliot and philosophers like Schelling referring to these opposites of movement and repulsion. Needless to say, cosmos is an amazing concept of being alive in an universe without end. Thank you.

Note. the power point presentation can be found at Connecting scales: from the infinitively large to the infinitively small -Stavros Katsanevas


Spyros Mercouris: what you did in your lecture is amazing. You demonstrated that nature and man are one, and you admire the mind of man being able to go deeper and deeper. The whole story started with the pre-Socratic philosophers.

Stavros Katsanevas

After the pre Socratic we have the classical approaches. Today we look only at the street lights and forget about the universe, while in pre Socratic times they had more contact with the universe. That was most natural as they were physical philosophers.

Today scientists try to manage uncertainty but never claimed that the particles are faster than light. That we do not know. We need more research, we need to prove ourselves as being wrong abou light and the permanent non permanent matter. What does the contrast with matter or particles having to move faster than light if not to dissolve tell us, that is a key question!


The discusssion Wang Yifang, of the Institute of High Energy Physics, Chinese Academy of Sciences. Studied in Stanford and MIT, and who is the key person who made the discovery of Nenotrinos, thereby making as head of the largest institute contributions to astro physics, was asked via Skype, if he could tell the audience in Olympia a few things. Unfortunately he was able to say that “it is a pleasure to speak about our planet. We can classify our activities: made some important discoveries.” Then, the Skype connection no longer worked.






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