INW 10 RJR

July 15-20, 2002

Parole in occasione dei sessant'anni di Remo Ruffini,
e
dei seminari tenutosi in Roma e Pescara.

To day we have a nice occasion to measure our progress in Astrophysics in these last thirsty years. We can compare the book by Martin Rees Remo Ruffini and J. Archibald Wheeler:

Black Holes, Gravitational Waves and Cosmology, edited in 1973

with what we know and search to day in Astrophysics and in elementary particle physics.

The progress in astrophysics is huge, still on lines of thought that do not contradict those opened in this book, with the discussion on the beginning, the end, the energy and the entropy of our Universe, unique or not. But during this week you will have occasion to speculate on this progress, with original ideas who are beyond my capacity.
I have devoted my life to study elementary particle physics in the laboratories established on Earth. Let me make a short comment on the progress in the relations between astrophysics and elementary particle physics. These relations are so strict and inter dependent, that we must think of them as a unique science with a variety of very different experimental approaches and detectors on Earth and in space, but with a common theoretical landscape.
Looking to the elementary structure of the world, we must ask how complexity arises in the Universe. We who work on the fundamental principles, mostly believe, as I do, that the basic theories are extremely simple. There are two of them.

The first is a unified theory of the elementary particles and all the forces of nature. It could even be that we already have that theory [I am copying from Gell-Mann (Plectics, Europhysics news, January/February 2002)], in the form of that wonderful candidate that has evolved from superstring theory into what is now called "M Theory".

The other fundamental theory is the initial condition of the Universe near the beginning of its expansion, some ten billion years ago. That may also be simple. In fact some specific ideas have been proposed about ways in which it could develop.

But the evidence of these two fundamental principles is still far from being certain and definite. Two problems at least hang over us, and should be solved with the coming new accelerators, the Tevatron and LHC.
One is the symmetry in nature, or not, between matter and antimatter: how did it happen that from the initial mixture descended the prevailing single one type matter? The other is the existence or not of a scalar particle, the Higgs, which could explain the origin and mass values of all other particles.

We know of the existence of these two problems since many years, at least thirty, but it will take time to resolve them. The cost of the high energy intense accelerators is heavy, and we know that it will take some years to have the reply we look for. The last news we received from Cern is that LHC shall be ready to give analysis and results by 2008 or 2009. Some partial or complete replies could come from the Tevatron, the proton antiproton machine of the FermiLab.
The problem of the long time in getting experimental replies produces a generational gap those 25-30 years old physicist who cannot measure themselves in the laboratory, for the accelerators are not ready to satisfy the urgent desire to know. I think that the best physicists of this epoch shall find the way to get new results by considering astrophysics and elementary particle physics as a unique science.
Unity of these two sciences is perhaps well demonstrated by our uncertainty in knowing which are the particles or entities which constitute the Dark Matter. This is a question which really seem to me to bind in real ignorance astrophysics and elementary particles, and which we shall have to resolve together.
We never, probably, were so conscious as today of how far are we from a complete knowledge of our universe, its components, complexity and possible end and origin. In some respect, we could say that we are at the origin of knowledge, At least with one comfort: to have better disclosed the limits of our knowledge, and perhaps our arrogance or over confidence in the interpretations of the history of our Universe. I hope that in the course of this conference Remo Ruffini and other authors shall compare for us the "spirit" and hopes of their 1973 book, which Ruffini wrote when be was thirty years old, with our certainties in astrophysics to day.
Let me express our best wishes for your future work: we know at least that we are leaving to sail a great still unknown Ocean, and we know of the convenience to use all possible detectors in space and Earth, and to analyze all possible theoretical models, as suggested to us by all observations on Earth, on space, on stars and Galaxies.