Nouveau livre de Krauss

Sortira en avril 2017. Je l'ai commandé immédiatement.

Ripples in the fabric of space-time

Albert Einstein predicted that gravitational waves would be produced in extremely violent events, such as collisions between two black holes. As these waves spread out, they compress and stretch space-time, producing ripples, whose presence could be detected by laser beams.

The physicist Lawrence Krauss sent out a tweet yesterday suggesting that the LIGO laboratory in the USA may have finally detected the ripples of gravitational waves.

We'll have to be patient for a while before learning whether or not this gigantic scientific information is true.

Thinking rationally about terror

Here's a brilliant short New Yorker article on the subject of urban terrorism by the exceptional US physicist Lawrence Krauss.

His conclusion is sobering but appeasing:

... a mass killing like that which occurred in Paris would not significantly affect the death toll from guns in the US

I take this opportunity of reminding my Antipodes readers that Krauss is the author of a momentous book on physics and philosophy: A Universe from Nothing. It reflects upon humanity's biggest question (which has often driven me crazy... at least for a moment or so): Why is there something rather than nothing at all?

Magicians reveal what the world's all about

For several years, I've been fascinated by the popular books of three physicists: Brian Greene, David Deutsch and Lawrence Krauss.

Funnily enough, although the three of them are writing about the same general subject—our state-of-the-art understanding of the nature of the universe—they rarely, if ever, get around to handling the same questions in comparable, if not similar, fashions. Moreover, in their latest books, they hardly even refer to one another's work.

It's easy to understand superficially why Greene, Deutsch and Krauss don't seem to have a lot to say to one another. Greene has been reputed for a long time as an adept of string theory, and there's no reason to imagine that the other two physicists are particularly keen on this theory. Earlier this year, Krauss became widely known through his presentation of an esoteric explanation of how the ultimate "free lunch"—obtaining something from nothingness—is a perfectly plausible phenomenon at a cosmic level.

As for the 59-year-old Oxfordian David Deutsch, he comes through to me as the most philosophical member of the trio. Indeed, he offers us a multiverse view of existence that is totally amazing. As in his first book, The Fabric of Reality, Deutsch pursues in The Beginning of Infinity his quest for a Theory of Everything inspired by the work of a somewhat heteroclite foursome: Karl Popper (epistemology), Hugh Everett (multiverse theory), Alan Turing (computation) and Richard Dawkins (evolution). Indeed, between the Popperian explanations of knowledge, the connotations of quantum theory leading to the existence of multiple universes, the vast theories of classical computing put forward by Turing (which are no doubt sufficient to handle, not only the DNA computer responsible for replication and life, but also the phenomena of neuronal computing) and finally the processes of Darwinian evolution and genetics so brilliantly presented by Dawkins, most observers would agree that we've no doubt covered many of the basic essentials of a scientific outlook on reality. Deutsch himself refers to these four grand dimensions of his global philosophical approach as strands (a word I like, which evokes weaving a fabric).

A few weeks ago, I was excited to learn that Deutsch has been working on a kind of fifth strand, of a subterranean nature, which he calls constructor theory. If you've got 47 minutes of free time, I urge you to click here to listen to Deutsch himself presenting this work. Basically, it's a matter of trying to understand why certain things are possible (even though they may have never actually happened yet) whereas countless other potential events are impossible because certain laws of physics have "blacklisted" them forever. In other words, he has enhanced astronomically the sense of the concept of possibility, to the point of claiming that anything and everything is strictly possible... provided only that we know of no law of physics that forbids such a happening, and therefore renders it impossible. Deutsch draw our attention to the strict binarity of the situation. Between the impossible (ruled out by physics) and the possible, there is no third way out. On the one hand, nothing—not even the most extravagant events—should be branded as theoretically impossible unless we are already aware of a law of physics that forbids such things. On the other hand, everything else should be thought of as theoretically possible.

In his eagerness to point out the counterintuitive nature of this thinking, Deutsch hit upon an amusing easy-to-grasp example, which goes straight to the heart of my Antipodes blog. Most of us agree that people on the other side of the planet Earth are in an upside-down position with respect to us, and vice versa.

That old Epinal image is funny but quite silly, of course, because nobody really believes that Antipodeans get around on their hands, with their Hobbit-like feet stretching towards the heavens. But are we truly ready to admit that the heads of Antipodeans point constantly in the opposite direction to our own heads? If technology were to offer me a magical real-time closeup view of Antipodeans, in strict conformity with our mutual orientations, in the same way that binoculars enable me to observe distant objects through my bedroom window, would I not be somewhat surprised to receive upskirt images of Antipodean ladies whose heads appear to be receding upwards into the sky? My surprise (which would be inevitable, I think) would seem to confirm that, to a certain extent, I've never really believed wholeheartedly that the heads of Antipodeans point in the opposite direction to mine. And David Deutsch considers that this mild form of surprise, or doubt, reflects my persistent quest for a third way out, between the possible and the impossible. My scientific culture persuades me that there is no law of physics that would forbid Antipodeans from getting around in an upside-down position with respect to me. So, I conclude that it's perfectly possible for this to be the case. At the same time, I consider that modern laws of celestial mechanics have quashed forever all remnants of flat-Earth theories, meaning that it's unthinkable that the heads of Antipodeans might point in the same direction as mine. And yet I don't seem to have gone one tiny step further and admitted explicitly, in a tangible concrete sense, that people down on the opposite side of the planet are truly presenting me constantly (if only the Earth were transparent) with an upskirt vision of their environment.

What David Deutsch seems to be saying (in a roundabout fashion) is that we would do well to consider, in an equally tangible and concrete sense, that we exist within a multiverse where the quantum effects admitted by today's laws of physics must be thought of, not only as possible happenings, but as garden-variety aspects of the fabric of everyday reality. And I'm not sure that many of us are prepared, at present, to assimilate profoundly that weird mode of looking at existence. Between archaic fairy tales (often supported by so-called commonsense) and hard state-of-the-art science, we persist in hoping, if not believing, that there must surely be some kind of convenient "third way out".

Blue light in the darkness

I came across an article in the French press about an ingenious device that apparently prevents night-time drivers from falling asleep at the wheel. It's simply a blue LED lamp fixed inside the vehicle, in the vicinity of the rear-view mirror, so that it shines into the driver's eyes.

                                         — photo CNRS/Université Bordeaux Segalen

Researchers at the CNRS (French national scientific organization) and the university of Bordeaux explain that the blue light of their embedded anti-drowsiness device acts upon the driver's biological clock by inhibiting the secretion of the melatonin hormone, which is responsible for inducing drowsiness. [For an in-depth presentation of this hormone, look up melatonin in Wikipedia.] According to its inventors, tests of the blue-light technique demonstrate that it's more efficient than coffee in the prevention of drowsiness... which is the main cause of mortal accidents on French autoroutes (highways). They add nevertheless that 17 per cent of their subjects were unable to complete the tests because the blue lamp shining in their faces made it totally impossible for them to drive at all.

Everybody agrees nevertheless that it's preferable to sleep well during the week that precedes any night-time driving, and to pull over for a 15-minute nap as soon as the first signs of drowsiness appear. That explanation about the advantages of sleep as a remedy for drowsiness is a bit like saying that there's no better remedy for hunger than food.

The idea of a life-saving blue light in the darkness reminds me of one of the loveliest short videos I've ever seen, created by the US cosmologist and science author Carl Sagan [1934-1996].

Sagan's origins were Russian, and he started his prestigious career as a popularizer of science by coauthoring a book with the Soviet astrophysicist Iosef Shmuelovich Shklovskii [1916-1985], Intelligent Life in the Universe (1966).

This was in fact the first serious English-language book ever published on this exciting theme, and it fascinated me at the time, in the late 1960s. Unfortunately, it's the kind of book that has dated rapidly and considerably, and the writing style and didactic content hardly match up to the brilliance of today's great authors of popular books on physics such as Brian Greene (The Hidden Reality, 2011), David Deutsch (The Beginning of Infinity, 2011) and Lawrence Krauss (A Universe from Nothing, 2012). Often, when I'm reading, I underline fragments that have impressed me greatly. In the book by Shklovskii and Sagan, I notice that I underlined the following words: (on page 248):

For all our feelings of self-importance, we are only a kind of biological rust, clinging to the surface of our small planet, and weighing far less than the invisible air that surrounds us.

I realize that I've always been attracted to sentiments that downplay human vanity. Be that as it may, here's Sagan's video on the pale blue dot in the middle of the sky:

Talking of extraterrestrial creatures, I would imagine that most of my readers have met up with the marvelous short story by the US science-fiction writer Terry Bisson entitled They're made out of meat. You can find it on the web by clicking here. It's so short that I've taken the liberty of including a copy here:

THEY'RE MADE OUT OF MEAT

"They're made out of meat."

"Meat?"

"Meat. They're made out of meat."

"Meat?"

"There's no doubt about it. We picked up several from different parts of the planet, took them aboard our recon vessels, and probed them all the way through. They're completely meat."

"That's impossible. What about the radio signals? The messages to the stars?"

"They use the radio waves to talk, but the signals don't come from them. The signals come from machines."

"So who made the machines? That's who we want to contact."

"They made the machines. That's what I'm trying to tell you. Meat made the machines."

"That's ridiculous. How can meat make a machine? You're asking me to believe in sentient meat."

"I'm not asking you, I'm telling you. These creatures are the only sentient race in that sector and they're made out of meat."

"Maybe they're like the orfolei. You know, a carbon-based intelligence that goes through a meat stage."

"Nope. They're born meat and they die meat. We studied them for several of their life spans, which didn't take long. Do you have any idea what's the life span of meat?"

"Spare me. Okay, maybe they're only part meat. You know, like the weddilei. A meat head with an electron plasma brain inside."

"Nope. We thought of that, since they do have meat heads, like the weddilei. But I told you, we probed them. They're meat all the way through."

"No brain?"

"Oh, there's a brain all right. It's just that the brain is made out of meat! That's what I've been trying to tell you."

"So ... what does the thinking?"

"You're not understanding, are you? You're refusing to deal with what I'm telling you. The brain does the thinking. The meat."

"Thinking meat! You're asking me to believe in thinking meat!"

"Yes, thinking meat! Conscious meat! Loving meat. Dreaming meat. The meat is the whole deal!  Are you beginning to get the picture or do I have to start all over?"

"Omigod. You're serious then. They're made out of meat."

"Thank you. Finally. Yes. They are indeed made out of meat. And they've been trying to get in touch with us for almost a hundred of their years."

"Omigod. So what does this meat have in mind?"

"First it wants to talk to us. Then I imagine it wants to explore the Universe, contact other sentiences, swap ideas and information. The usual."

"We're supposed to talk to meat."

"That's the idea. That's the message they're sending out by radio. 'Hello. Anyone out there. Anybody home.' That sort of thing."

"They actually do talk, then. They use words, ideas, concepts?"

"Oh, yes. Except they do it with meat."

"I thought you just told me they used radio."

"They do, but what do you think is on the radio? Meat sounds. You know how when you slap or flap meat, it makes a noise? They talk by flapping their meat at each other. They can even sing by squirting air through their meat."

"Omigod. Singing meat. This is altogether too much. So what do you advise?"

"Officially or unofficially?"

"Both."

"Officially, we are required to contact, welcome and log in any and all sentient races or multibeings in this quadrant of the Universe, without prejudice, fear or favor. Unofficially, I advise that we erase the records and forget the whole thing."

"I was hoping you would say that."

"It seems harsh, but there is a limit. Do we really want to make contact with meat?"

"I agree one hundred percent. What's there to say? 'Hello, meat. How's it going?' But will this work? How many planets are we dealing with here?"

"Just one. They can travel to other planets in special meat containers, but they can't live on them. And being meat, they can only travel through C space. Which limits them to the speed of light and makes the possibility of their ever making contact pretty slim. Infinitesimal, in fact."

"So we just pretend there's no one home in the Universe."

"That's it."

"Cruel. But you said it yourself, who wants to meet meat? And the ones who have been aboard our vessels, the ones you probed? You're sure they won't remember?"

"They'll be considered crackpots if they do. We went into their heads and smoothed out their meat so that we're just a dream to them."

"A dream to meat! How strangely appropriate, that we should be meat's dream."

"And we marked the entire sector unoccupied."

"Good. Agreed, officially and unofficially. Case closed. Any others? Anyone interesting on that side of the galaxy?"

"Yes, a rather shy but sweet hydrogen core cluster intelligence in a class nine star in G445 zone. Was in contact two galactic rotations ago, wants to be friendly again."

"They always come around."

"And why not? Imagine how unbearably, how unutterably cold the Universe would be if one were all alone ..."

Good books

Britain's New Scientist weekly has just put out a selection of 25 popular science books that "have changed the world" [here].

I would have been a little worried if this list of books had included many works that I did not know. On the contrary, I was thrilled to discover that I had read 15 of their suggested titles, while most of the remaining titles rang a bell (in the sense that I had heard of them, and had a good idea of their themes). The only one of the 25 books that was a total newcomer to me was The Man Who Mistook his Wife for a Hat by Oliver Sacks (1985). Here are those that I've read:

•  A Brief History of Time by Stephen Hawking (1988)

•  Brighter Than a Thousand Suns by Robert Jungk (1956)

•  Godel, Escher, Bach by Douglas Hofstadter (1979)

•  Guns, Germs and Steel by Jared Diamond (1997)

•  On the Origin of Species by Charles Darwin (1859)

•  The Ascent of Man by Jacob Bronowski (1973)

•  The First Three Minutes by Steven Weinberg (1977)

•  The Language Instinct by Steven Pinker (1994)

•  The Selfish Gene by Richard Dawkins (1976)

•  Silent Spring by Rachel Carson (1962)

•  The Double Helix by James Watson (1968)

•  The Emperor's New Mind by Roger Penrose (1989)

•  The Mysterious Universe by James Jeans (1930)

•  The Naked Ape by Desmond Morris (1967)

•  What is Life? By Erwin Schrödinger (1944)

At the top of this list, the "big three" for me would be Dawkins, Watson and Pinker. I would have included a title by David Deutsch... but it's a fact that he remains a bit too recent to have changed the world yet. Maybe "will change the world". The same could be said of Lawrence Krauss.

Awaiting a weighty book

At the end of my blog post of 16 July 2011 entitled State of things [display], I suggested that readers might sit down quietly for an hour to watch a splendid talk by an outstanding American theoretical physicist, 57-year-old Lawrence Krauss.

I've just been pleasantly surprised to learn—in a note from Krauss himself, published yesterday [display]—that this talk actually took place some two years ago, at the instigation of Richard Dawkins and Robin Elisabeth Cornwell [Executive Director of the US branch of the Richard Dawkins Foundation for Reason and Science]. Later, the Foundation decided to post the talk video to YouTube… and it went on to log over a million views. This doesn't surprise me at all, since the subject is awesome.

Not surprisingly, friends of Krauss soon got around to convincing him that he should write a book on this fascinating subject of the way in which "nothingness" transforms itself constantly (with no help from any gods, just pure science) into "somethingness". When you think about it, it's a bloody good pretext for a book, to say the least: the sort of stuff that the Holy Bible would refer to as "good news". (I'm joking, of course. The authors of the poor old Bible wouldn't know what the fuck we were talking about.)

This momentous book will be coming out on 10 January 2012. Meanwhile, you can download (from the above Foundation link) the text of a splendid Afterword written by Dawkins for the imminent Krauss book. Inspired by the famous biblical words "Jesus wept" [John 11-35], I feel like summarizing the situation: Dawkins wondered. Wondered in awe at the words of a fellow scientist… without claiming that he (or many of us, for that matter) might be capable of following all the mathematics and physics that culminate in such mind-boggling conclusions. In any case, the words of the science poet Dawkins (who speaks from my level) are beautifully inspiring. And I'm awaiting eagerly the weighty words of Krauss.

State of things

It's hard to single out the nonfiction book that marked me most when I was a young man. Objectively, I would probably have to say it was History of Western Philosophy by Bertrand Russell, since I discovered Russell's rambling and sketchy compendium in Paris in 1962 and, up until today, it has remained one of my bedside books.

Before then, a science book that made a huge and lasting impression upon me was The Nature of the Physical World by the English astronomer Arthur Eddington, written in 1928. He was a Quaker (which might have aroused my suspicions), but Eddington was also, after all, one of the first and finest interpreters of the newfangled theories of Albert Einstein. So, I was most impressed by his excellent style of science writing.




What I liked most about Eddington's views on the cosmological state of things was the fact that he left a tiny window open for spiritual beliefs and religious faith. I remember saying to myself, as it were: "OK, Eddington's explanations on the nature of the Cosmos are fine for the moment, even though they're obviously inadequate. But there's a good chance, hopefully, that we'll get around to finding God, one of these days, in the interstices." In fact, I was both a naive and lazy thinker.

In a nutshell, that's truly what I believed for years, for decades… even during the time that I fell in love, upon my arrival at Gamone, with the fabulous tale of Master Bruno, founder of the Chartreux monastic order. But the truth of the matter is that we're no longer in the same peaceful ballpark as Bruno and company. In the course of the few decades that separate me from my reading of the charming Quaker Eddington, Science has started to come apart at the seams, while Religion has been eternally rubbished.

We're awaiting news, not from a religiously-inspired science-writer, and even less from the Holy Spirit, but from the Large Hadron Collider, which talks to us in terms of String Theory. But will we necessarily understand the sacred Word of the Collider? Probably not, at least neither exactly nor explicitly, because it's all a matter of ethereal mathematics, which is akin to a mixture of abstract art and poetry. But it's infinitely better than the supposed Word of God, horribly fuzzy and irrevocably has-been.

The following video is a talk on cosmology by an amazing US intellectual, Lawrence Krauss. It lasts an hour, but I strongly urge you to get settled comfortably in front of your computer to watch it from the beginning to the end.