Wednesday, January 21, 2009

Across the scientific fields

Philip Anderson argues that although reductionism is the effective way to do science, it does not necessarily lead to an understanding of the whole:

"The ability to reduce everything to simple fundamental laws does not imply the ability to start from those laws and reconstruct the universe."
P. Anderson, More is different, in Science (1972), vol. 177.

For him, science is fundamental not only at the level of particles but also at every higher and more complex levels: an object, a fluid, an ocean, a body, a society, Earth, the Universe:
"The behavior of large and complex aggregates of elementary particles, it turns out, is not to be understood in terms of a simple extrapolation of the properties of a few particles. Instead, at each level of complexity entirely new properties appear, and the understanding of the new behaviors requires research which I think is as fundamental in its nature as any other."
P. Anderson, More is different, in Science (1972), vol. 177.

This point of view of science(s) has also been recently expressed by Edward O. Wilson in his book Consilience. and Ian Stewart in his book Does God play dice?.

Is religion the root of all evils?

These days, surely and rightfully because of the attacks on science by advocates of intelligent design, a wave of essays have attacked strongly religions. We can also find regularly essays that give the feeling that if religions would be wiped out on Earth, wars, ignorance, murders would go away with them.

I am a bit uncomfortable with that idea. Yes, religion has proven, more so in that far past than during the twentieth century, that it can kill a lot of people. The problem with that interpretation is that in many cases, religion was the fuel, the catalysis, the motivating stick, but not necessarily the actual cause of the problem. Many so-called religious wars have started, not because they were protestant and we were catholic, not because they were muslims and we were christians, but because of geopolitical reasons, money and power. Ignoring those reasons and blaming religions alone is a dangerous and self-blinding view of the world. And failing to recognize that power, in many cases, drives those wars and conflicts is taking the risk to be inefficient in the resolution of those problems.

Saturday, January 17, 2009

The anthropic principle and the evolution of the universes

This is a short note on the current controversies concerning the formation of our Universe, developed in the book What is your dangerous idea?. Recent research has come to the conclusion that for our present Universe to exist, the so-called 'universal constants' have to have precise values, otherwise, the formation of galaxies and stars would not occur at a pace for life to exist. Furthermore, string theorists are discovering that there is not a single solution (and a unique set of 'universal' constants) but a 'landscape' approaching 10500 solutions and there are thus maybe many other universes with different constants that lay beyond the limit of our own!

Those conclusions, although yet highly speculative, are in the same time 'exciting and humbling' according to Brian Greene, and I would add unsettling for some. Why unsettling? First, because it poses the fundamental question of the existence of our Universe and why we were so lucky in the first place that life can exist. One rhetoric is to state that it is not really luckiness because if our Universe would have different 'universal' constants, life would not exist and we would not be here to complain that we were not lucky: this is the so-called anthropic principle.

The second and most unsettling point of those conclusions is the realization that the idea of a 'universal' set of laws that would dictates all universes, laws that are fundamental and are at the bottom and origin of everything, might not exist. Instead, these laws would be valid only locally and be pure environmental facts:

"Well, [thoses ideas] do threaten physicists' fondest hope-the hope that some extraordinarily beautiful mathematical principle will be discovered that would completely and uniquely explain every detail of the laws of particle physics.
[...] What further worries many physicists is that the landscape may be so rich that almost anything can be found-any combination of physical constants, particle masses, and so forth. This, they fear, would eliminate the predictive power of physics. Environmental facts are nothing more than environmental facts. They worry that if everything is possible, there will be no way to falsify the theory-or, more to the point, no way to confirm it."
Leonard Susskind, The "landscape", in What is your dangerous idea?
"The end of «fundamental» theoretical physics (the search for fundamental microphysical laws-there will still be lots of work for physicist who investigate the host of complex phenomena at larger scales) might very well occur not with a theory of everything but with the recognition that all so-called fundamental theories that describe nature are purely phenomenological-that is, derivable from observational phenomena-and don't reflect any underlying grand mathematical structure of the universe which would allow a basic understanding of why the universe is the way it is."
Laurence M. Krauss, The world may be fundamentally inexplicable, in What is your dangerous idea?

I will conclude with two other ideas that, without resolving the problem and erase any controversy, are not the less interesting. One, presented in the book by Paul Steinhardt, is to make the assumption that the 'universal' constants are not constant but vary slowly with time, so slowly that 1) our universe had time to have shrink and expand cyclically many times already (which would suggest that the Universe is much older than actually thought) and 2) we have not yet been able to measure their variation. Accepting this assumption avoid to call for other universes. Instead, one universe, our own, would slowly drift across different regimes of the 'landscape' and the one we are now is just the one at a particular time.

The second and bolder idea, presented by Lee Smolin, is to see our present universe and its 'universal' constants not as a result of chance, but a result of natural section. The idea is to apply Darwin's ideas of selection and co-evolution to even the fundamental laws and constants. If true, the theory poses, as usual, new questions; for instance, is there a meta-law, like the second law of thermodynamic, that would dictate how laws evolve? Smolin concludes that if the theory, which can be falsifiable, come to be true
"Einstein and Darwin will be understood as partners in the greatest revolution yet in science, a revolution that taught us that the world in which we are embedded is nothing but an ever-evolving network of relationships."
Lee Smolin, Seeing Darwin in the light of Enstein;seeing Einstein in the light of Darwin, What is your dangerous idea?

Wednesday, January 14, 2009

The real reason why we should fight human-induced climate change

The fight to convince people that we should act to prevent human-induced climate change has been on for many years now. Many rhetoric have been used but Oliver Morton, in What is your dangerous idea?, is afraid that some of the arguments might back-fire because they are missing the real reason. This is a controversial issue.

According to Norton, we should not fight necessarily because ecosystems are going to disappear. His point is that Earth has witnessed harsher changes, the living has endured (so far) far more dramatic blows (none of the least example being the Permian-Triassic extinction, 251 million years ago, when nearly 90% of life was killed), yet life and Earth still exist and are relatively healthy (to our standards).

If we have to fight, it is because people are going to suffer. They will suffer because they will be displaced by the rising sea level, because their way of life will be destroyed, because social disorders will trigger wars and diseases:

"The most important thing about environmental change is that it hurts people; the basis of our response should be human solidarity.
The planet will take care of itself."
Oliver Norton, What is your dangerous idea?, Our planet is not in peril.

Any other arguments are near-fallacies and may back-fire. Controversial, indeed.