Lee Smolin
52 quotes
Biography
"One possibility is: God is nothing but the power of the universe to organize itself."
"Is the flow of time something real, or might our sense of time passing be just an illusion that hides the fact that what is real is only a vast collection of memories?"
"Since the 1960s, particle theory had been split into two groups: those following the atomism of the quark theory and those who had followed the anti-atomism of that had led from the bootstrap program to the string theory. What happened in 1984 was that it was realised that string theory could combine and satisfy the aspirations of both approaches to fundamental physics. Thus, the community of gauge theorists, driven by the failure of the proton decay experiments to search for new ideas that could unify physics, all of a sudden encountered their old friends, the string theorists, in the middle of what might be called a desert of disappointed expectations."
"The first principle of cosmology must be 'There is nothing outside the universe'. This is not to exclude religion or mysticism... But if it is knowledge that we desire... we need to seek answers to questions about the things we can see... only things that exist in the universe."
"There is no meaning to space that is independent of the relationships among real things of the world. ...Space is nothing apart from the things that exist. ...If we take out all the words we are not left with an empty sentence, we are left with nothing."
"The geometry of space changes when things in the universe change their relationships to one another."
"There are unfortunately not a few good professional physicists who still think about the world as if space and time had an absolute meaning."
"I believe that the main lesson of relativity and quantum theory is that the world is nothing but an evolving network of relationships."
"The relational picture of space and time has implications that are as radical as those of natural selection, not only for science but for our perspective on who we are and how we came to exist in this evolving universe of relations."
"We are the result of processes much more complicated than the small aspects of our lives and societies over which we have some control."
"There is no fixed, eternal frame to the universe to define what may or may not exist."
"There is nothing beyond the world except what we see, no background to it except its particular history."
"We have known since the middle of the nineteenth century that the world is not composed only of particles. ...the world is also composed of fields. ...General relativity is a theory of... the gravitational field. ...Because there are three sets of field lines, the gravitational field defines a network of relationships having to do with how the... lines link with one another. ...This is why we call relativity a relational theory."
"In the theory of electric fields it is assumed that points have meaning. ...Physicists using general relativity... cannot speak of a point, except by naming some features of the field lines that will uniquely distinguish that point. ...the network of relationships evolve with time... constantly changing."
"There is no time apart from change. There is no such thing as a clock outside the network of changing relationships. ...one can only compare how fast one thing is happening with the rate of some other process."
"Time is described only in terms of change in the network of relationships that describes space."
"It is absurd in general relativity to speak of a universe in which nothing happens."
"Neither space nor time has any existence outside the system of evolving relationships that comprises the universe. Physicists refer to this feature of general relativity as background independence."
"In quantum theory, distance is inverse to energy, because you need particles of very high energy to probe very short distances. The inverse of the Planck energy is the Planck length."
"We detect light and particles that have traveled billions of light years on their way across the universe to us. During the billions of years of travel, very small effects due to quantum gravity can be amplified to the point that we can detect them."
"Since the 1950s, the key equation of quantum gravity has been called the Wheeler-DeWitt equation. Bryce DeWitt and John Wheeler wrote it down, but in all the time since then, no one had been able to solve it. We found we could solve it exactly, and in fact we found an infinite number of exact solutions."
"I was joined by Carlo Rovelli, and we were able to make a full-fledged quantum theory of gravity... This became loop quantum gravity."
"While most people... were seeking to modify the principles of either relativity or quantum theory, we surprised ourselves (and many other people) by succeeding in putting them together without modifying their principles."
"There is a smallest unit of space. Its minimum value is given by the cube of the Planck length... If you take a volume of space and measure it to a very fine precision... It has to fall into some discrete series of numbers, just like the energy of an electron in an atom. ...we can calculate the discrete areas and volumes from the theory."
"Some of the effects predicted by the theory [of loop quantum gravity] appear to be in conflict with one of the principles of Einstein's special theory of relativity... that the speed of light is a universal constant. ...Photons of higher energy travel slightly slower than low-energy photons. ...the principle of [general] relativity is preserved but Einstein's special theory of relativity requires modification. ...A photon can have an energy-dependent speed without violating the principle of [general] relativity!"