Friday, November 23, 2007

Really? Seriously?

Sometimes I read a science article online or in the newspaper that I think is poor. This one I just don't know how to interpret. Lawrence Krauss is a solid guy, a very strong public advocate for science, and a very good popularizer of physics. Still, the idea that our observations of dark energy have somehow collapsed the quantum state of the entire universe is, umm, nuts on the same level as saying that the moon doesn't exist if no one is looking at it. There's no question that there are subtleties in worrying about applying quantum mechanics to the universe as a whole. Still, this carries the "spooky action at a distance" idea a bit far.

7 comments:

Anonymous said...

Hi Doug,

The article was picked up by the New Scientist, which is best described as a "tabloid" science magazine. Larry Krauss' paper was submitted to Physical Review Letters, which hopefully will be a little more discerning.

Incoherent Ponderer said...

I saw this on woit's blog, and don't know what to think. Is it that the story and comments are so misinterpreted by the media? Or is it actually accurate description of Krauss' paper?

But if it is misinterpreted, one could make an argument that it still raises some interest in popular science circles, and make people aware of quantum weirdness? I disagree with this argument - you can raise public interest in science by reporting actually TRUE stories, instead of hyping up this type of BS (=bad science).

But taking it all seriously, is Krauss implying that capturing and measuring (=destroying) photons and other particles with detectors affects the entire universe in some sort of cosmic "butterfly effect"?
But even leaving aside the size of Earth vs. size of universe arguments for a moment, these earth-bound photons would be destroyed no matter what. Does it really matter if the particles get destroyed by means of hitting silicon dioxide in a form of beach sand, or hitting depleted doped silicon in a form of CCD chip?

Either way, assuming the story is not grossly twisted/blown out of proportion by media people, this is an example of how out-of-touch with reality some theorists are.

I have to admit - I had a lot more respect for Krauss before reading this news release.

NE1 said...

Krauss has literally posted a mea culpa on Woit's blog, and apparently changed the last two sentences on the paper. Personally, I think sentences like "Several open questions are raised, including ... whether cosmological observation within a given metastable universe may alter its lifetime" leave him on the hook. It's pretty sloppy.

Anonymous said...

I agree it was sloppy... as it was the last sentence of a paper that was devoted to calculating something of substance I did not devote the time I should have to formulating it.. it was referring to work that Alan Guth and I had been discussing, and the cauasl implication that appeared to have been taken from it was most unfortunate. I believe the clearer words in the new last sentences make it clear that causality is not the issue...

LMK

Alison Chaiken said...

Is Krauss's paper actually wrong or just dismayingly lurid? In other words, if you received the paper to formally review, what would be your scientific criticisms as opposed to your feelings of embarassment?

Doug Natelson said...

Hi Alison - I have not read the paper. From what I know about quantum measurements, I don't think it makes a lot of sense to ask whether some internal degrees of a system can somehow "observe" the state of the system in a Copenhagen sense. In the particular case at hand, the vacuum state of the universe interacted with many many degrees of freedom out there over billions of years (and hence should have "decohered", in my way of thinking) before the relevant photons ever interacted with our observing equipment. I take Prof. Krauss at his word - that he was to glib in dealing with a reporter who spotted his paper on the arxiv.

WebVisible said...

Is it that the story and comments are so misinterpreted by the media?