Prof. Penrose, one of the world's greatest experts on relativity and quantum theory, combines the two theories
Prof. and Sir, Roger Penrose
Some of the world's greatest physicists arrived in Jerusalem this week for a conference organized by the Israel Academy of Sciences, which will end on Wednesday, on the 100th anniversary of Einstein's theory. The opening lecture was held on Sunday at the nearby Van Leer Institute. The honor of opening the conference was given by the Academy to Prof. Roger Penrose
Prof. Menachem Yaari, President of the Israel Academy of Sciences briefly introduced Prof. Penrose:
"Professor Penrose proved that it will be impossible to transfer the human brain to a computer, no matter how sophisticated the technology of that computer is. Prof. Penrose proved that the tiling problem is a problem that a computer cannot solve, no matter how complex it is, but Roger Penrose succeeded. And it proved that it is impossible to reduce Prof. Penrose's mind. Reductionism is wrong.”
Rafi Levin, a member of the Academy, introduced Prof. Penrose in a more in-depth way: "Professor Sir Roger Penrose from Oxford is regarded as the most creative person in the field of relativity, with the exception of Einstein himself. We are glad he is here with us. He received a knighthood in 1994. He wrote many technical books, but I especially want to point out that the books he wrote try to explain his view of physics and human self-awareness to the masses."
"He started his career as a mathematician. As a mathematical physicist, Roger proved the theories about the singular points in the theory of relativity - the big bang and black holes were the basis for his winning the Wolf Prize with Hawking. Singularities have implications for our understanding of the origin of the universe and its possible fate. In addition, he placed quantum mechanics within the framework of general relativity, which includes gravity."
"Science begins with an attempt to understand the world around us. In the early 20th century Einstein and others increased the scale. Einstein was interested both in the scale of light years and in the scale of the diameter of the molecule - the subject of Einstein's doctoral degree. Einstein was unable to unify the very large and the very small which quantum theory ruled. Penrose succeeded in doing so. Recently, Penrose has been trying to understand human cognition and how it relates to what a computer can or cannot do, but tonight he will talk about Einstein, Einstein's perspective.
Prof. Penrose: "It is a great honor for me to come and talk about Einstein." It is especially important to come to Israel, because at the end of his days, Einstein, although he was a US citizen and said that there was no country to which he belonged, helped establish the State of Israel and the Zionist project. "The topic of the lecture is, as mentioned, the Einsteinian perspective. Einstein said that if there are different aspects of a physical phenomenon, even if they seem contradictory, he sees beyond that and searches for what the thing itself is. There is something that has a deep existence: reality and objectivity."
How Einstein saw the light. He wrote several articles, he wrote about the diameter of the molecule, about the Brownian motion (which made Einstein an important scientist even if he had not written anything else). Nobel Prize - the idea that light should be treated like a particle. In one of the articles light behaves according to Maxwell's laws (as an electromagnetic wave) and in the other - as a particle. He probably had a deeper view of light - from some aspects it looks like a wave and from other aspects like a particle, but there is a deeper look where the paradox is resolved, it's called the quantum theory, but Einstein still didn't know exactly what it was about, he only knew that there had to be some kind of explanation.
We know that in the theory of relativity he said that he sees the world as if it were traveling on a beam of light.
I wanted to talk mainly about special relativity and general relativity.
"Special relativity depends on different observers and how they see the same universe but they measure time and distances differently. Even so, his view of the nature of light was unknown until Minkowski. Today we formulate the special theory of relativity so that time and space should have 4 dimensions, initially Einstein did not like this reference. The generalization to general relativity adds another dimension - gravity."
: There are many coordinate systems in space-time and we can place them as we wish. The way is to start with one coordinate system, add another one and find the connection between them and so on. In each coordinate system you see something different but they are just other aspects of the entities you want to see. These entities are objective factors - space and time. Einstein regretted the name he chose - relativity because it is about absolute space-time. Space-time is objective, the coordinates that every observer sees are the subjectivity. This is treated as a mathematical convenience rather than what a particular viewer would see. For example, a painter draws a straight road, in which the lines are parallel and will never meet, in the painting you see that the lines meet on the horizon. Another way to look at it is the levy plane. Geometry of the levies is a mathematical way to describe the subjectivity in the choice of coordinates.:
From Einstein, Penrose moved to the theory he himself developed. The next drawing showed the arrow going from the quantum world to the classical world - like a mermaid connecting the world of the sea to the world outside.
Mona Geiger indicates a sound in the real world created by a particle - in the quantum world.
The paradox - classical physics includes deterministic equations that say if you know the state of the system at one point, they tell you what will happen at any time in the future and what they did at any point in the past. (Newton, Einstein, Maxwell). Even in the quantum theory there are systems of equations - Unitary Evolution/ they are also deterministic equations, but different.
People think that the quantum equation is not deterministic but this is not true. They may be complex but that does not make them non-deterministic. The problem arises from the contrast between the two sets of deterministic equations. The equations of the alternatives in which the photon can be found must be treated as equations containing complex numbers, otherwise, if we only place percentages of probability they will cancel each other out. In the connection between the two there is a non-deterministic section - a place where all the equations collapse.
Einstein and his colleagues at the Einstein-Podolsky-Rosen bridge tried to prove that quanta is not complete theory. John Bell pointed out that with Einstein's experiment, the quantum theory can be proven, because if you measure two photons shot to different places, despite the distance of 12 meters, they are still two parts of the same thing. These equations were proved 15 kilometers apart, and cannot be treated as separate classical units. ZA that quantum is a non-local theory - there is a connection between distant particles. Suddenly the difference in which the quantum theory deals with small distances - and the classical one with large distances - disappears because it is impossible to define 15 kilometers as a small distance.
Here comes Schrödinger's cat experiment. "I have no problem with killing the imaginary cat. It is also possible to save him by using a mirror and show the cat in a super position - alive and dead at the same time."
Einstein did not go far enough. In a debate with Niels Bohr he tried to argue that the equations do not add up, the next day Bohr proved that they did, precisely based on the theory of general relativity." According to Penrose: nevertheless there is a paradox and Einstein was right - after a certain time, the two states will finally be one state. "The energy it will cost you to tear the two identical particles apart. H/Eg. These things can be tested experimentally in the framework of which they will be confirmed or disproved: after a certain time the system collapses into one of the possible situations.
Finally, some comments about Einstein's view on pacifism: "In my opinion - killing in war is like murder." And another quote: My pacifism is an instinctive feeling that war repels me because murdering human beings is repugnant. My approach is not derived from any intellectual theory but is based on the basic antipathy to any type of evil." And another quote: "Peace cannot be maintained by force but only by understanding"
Penrose adds, following Einstein, that conflicts in the world should also be looked at as inclusive and not as isolated points, and in addition, communication has become easy today, so it is easy for us to know what is the point of view of others on the same reality.
And for those wondering what the subtitle means: "Schrödinger's Mermaid"? Well, that was the title that Penrose gave to the slide in which Hans Christian Andersen's mermaid was drawn looking at the beach where you can clearly see houses, trees and roads and at the bottom of the painting you see a mix of coral fish and underwater creatures. The land analogy is classical physics, the sea is quantum mechanics and the mermaid is the arrow connecting the two physics.
Penrose's tiling, on the Physics Plus website
The program of events until Wednesday 19.04.2005 (English, PDF)
Special thanks also to Nir Lahav, for his help.
