December 2, 2007

Stupidity Supernova, Part II

The past week or so has had one of the densest concentrations of dumb physics stories that I can remember. Sadly, this post got so big that I had split it up.

Paul Davies
The excellent, The Physics of Time Asymmetry, is sitting over on my shelf. That is all I knew about Davies until I heard that he wrote an op-ed in the NY Times based on the idea that science necessitates the same level of faith as religious superstition. I was happier when all I knew about him was that book. CV and PZ Myers offer good responses. The less said about that op-ed the better.

We Shorten the Life of the Universe by Observing it
A few weeks ago Lawrence Krauss and James Dent posted an article to the arxiv about the cosmology of false vacuum decay. The idea behind the false vacuum theories is that the big bang may have arisen as a quantum fluctuation providing the energy and matter permitting the cosmos to...exist. Usually, this is related to the mechanism for inflation, but the idea that a bubble with nearly zero net energy quantum fluctuated itself into existence is sometimes offered as response to that eternal question of how it all began. However the reason I say "nearly zero" is that a fluctuation with a net amount of energy is forced to recollapse eventually. If there is a great deal of energy & matter this must happen soon, and if there is none, the false vacuum state can exist eternally. (Matter is positive, and gravitational attraction is negative, which is how they could manage to balance). Dark energy is seen in some of these models to represent the energy of the original vacuum, and so the amount of dark energy in the universe is the determining factor in how stable this temporary* false vacuum state is. We could then see from observations then that the universe has lasted longer than it is supposed to have, based on the statistics of quantum field theory.

Furthermore, being part of this quantum state, the value for the dark energy may exist within a range of values until observation pins it down. As far as I can tell, what they said in this paper was that at the current time, what we know about dark energy allows it to take a range of values, some good and some bad for the longevity of the universe. But if we constrained it definitively, it might end up being something that implies the false vacuum has persisted well past the point where it should have recollapsed. Or possibly the mere fact that we are able to measure it would be what implies that. Either way, the point would be that we might make observations that hint at our doom at the hands of a metastable quantum fluctuation.

OK. So this isn't the stupid part. The stupid part is that the Telegraph and its crack staff of junior varsity science journalists wrote up the article with the conclusion that it is the observation itself which is causing the vacuum decay. And they do it with all the grace and delicacy of a bull sipping tea. The thing that they keep missing in this piece is words like "imply" and "suggest," and instead blare out "Mankind 'shortening the universe's life'" in the title. And the quotes even make it appear that someone said this, while this is most definitely not the case. Or the caption for the photo of a completely irrelevant nebula that bears the totally erroneous caption "Cosmologists claim by observing dark energy the universe has been nudged closer to its death." No! "They"! Don't!

Krauss, who was interviewed for this, was clear (or at least as clear as you can get when describing field theory to a thousand monkeys typing on a thousand typewriters) on the fact that astronomers were not shortening the lifespan of the cosmos, saying

"In short, cosmological observations may suggest that the quantum state of our universe is such that the probability of long-term survival is limited," ...

And Prof Krauss stresses that resetting the cosmic clock was not something we have done to the universe but rather what our cosmologically observations may imply about our knowledge of the cosmic clock: "I did not mean to imply causality - namely that our measurement itself reduces the lifetime of the universe - but rather that by being able to make our measurement we may thus conclude that we may not be in the late decay stage."
The authors** then make the shocking decision to follow this up with the phrase "This is not the only damage to the heavens that astronomers may have caused..."

Forget science literacy, where is the regular literacy?


*In which thousands of generations lived and died, and billions upon billions of galaxies roared into existence and faded away. And the Mets managed to win the World Series twice.

**Yes, I'm sticking with authors, plural. That monkey-typewriter joke was gold.


Part I - Gregg Easterbrook: The Second 'g' is for 'gigantic moron'
Part II - Astronomers: Universe Killers
Part III - Surfer Physics
Part IV - Inane Physics Story Trajectories

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