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Our future, our universe, and other weighty topics


Saturday, August 9, 2014

The Quixotic Quest of the Multiverse Hunters

There is a certain type of sensationalist that I might call an inkblot sensationalist. I derive the term from the psychological testing technique of giving someone an inkblot, and asking him to tell what the ink blot represents. The technique was pioneered by Rorschach, who found that people would give all kinds of imaginative interpretations when presented with ordinary ink smudges. An inkblot sensationalist is someone who takes some murky blob of pixels, and interprets it in some sensational way, as a sign of some thing of enormous significance.

A recent example of inkblot sensationalism was the television program Aliens on the Moon: The Truth Exposed. The program consisted mainly of sensational interpretations of magnified lunar photographs, suggesting that some of the blurry pixel blobs were signs of alien bases and alien mining activity. But it may be that if you look through thousands of photos of purely natural landscapes, and magnify them sufficiently, with sufficient imagination you can find something that looks to you like artificial activity, even when nothing is there.

Below is the latest lunar example of inkblot sensationalism. Someone has found what looks like a man and his shadow on the moon. That seems pretty exciting, until you realize that it really looks more like a shadow and its shadow, not a man and his shadow. 

Image Credit: Google Earth/Youtube.com

Another example of inkblot sensationalism is when a paranormal investigator posts a photo with a little white smudge or white blur, implying that is possible evidence of a ghost. Having just read the sensational story of the ghosts of flight 401, I would not at all exclude the possibility that a ghost might be photographed. But if you are going to claim to have evidence of a ghost, it had better be something more than just a blurry white smudge on your photo, as such smudges can be produced by fingerprints on a lens, insects flying near a lens, or a speck of dust floating in the air.

Another example of an inkblot sensationalist may be a scientist who scans the cosmic background radiation, claiming to find little parts of it that are evidence of some other universe beyond our own. We saw an example of this in the article Beyond the Horizon of the Universe by physicst
Laura Mersini-Houghton. Studying the cosmic background radiation (believed to be the faint afterglow of the Big Bang), Mersini-Houghton claimed to find 9 possible signs of evidence for another universe. At least one of these claimed “signs” was ridiculous: the non-observation of supersymmetry (as if a non-detection of anything could be evidence for another universe). Other items on Mersini-Houghton's list seemed to be just flimsy cases of looking for some unexplained anomaly, and claiming that as evidence for another universe. But some of the things mentioned by Mersini-Houghton were anomalies that had been named or suggested by other cosmologists: a large-scale “Dark Flow,” a “cold dark spot” in the cosmic background radiation, and a claimed linear feature of the cosmic background radiation called “the Axis of Evil.”

The idea of trying to find evidence for other universes by looking at features of the cosmic background radiation in our universe seems like a quixotic quest (I will avoid the less polite term “fool's errand.”) Even if we were to find a particularly striking feature in that radiation, it would merely tell us something about our universe or its history, rather than being an indication of some other universe. It should also be noted that the cosmic background radiation is essentially featureless, because it is uniform to 1 part in 100,000. The visual below illustrates the point.

cosmic background radiation

Recent findings have not been kind to Mersini-Houghton's thesis. Using the latest and greatest observations from the Planck satellite, no less than 175 scientists co-wrote a paper last year concluding that there is no evidence for Dark Flow. They said flatly, “There is no detection of bulk flow.” You can read here a New Scientist story reporting on this paper. The story says, “The sharpest map yet made of light from the infant universe shows no evidence of 'dark flow.'"

Now there is a new scientific paper that casts doubt on other items on Mersini-Houghton's list. The paper is entitled “Planck CMB anomalies: astrophysical and cosmological secondary effects and the curse of masking.” The paper refers to a process called masking, whereby scientists subtract foreground signals to try to get at an underlying background signal. Imagine if you have planted a tape recorder in the home of a mobster who is unaware of eavesdropping devices in his house. Perhaps the mobster always turned on the radio while he was talking, so that no one could detect his words. You might then create some technique for subtracting the sound of the radio, to get at the background signals of the mobster's voice. That would be an example of masking. Scientists use similar techniques to “mask out” foreground signals to get at background signals such as the primordial cosmic background radiation, believed to come from the very early universe.

The authors of the new paper (discussed in this phys.org article) point out that this masking process seems to exaggerate certain parts of the cosmic background radiation. The authors argue that the so-called “Axis of Evil” is not a significant feature of the cosmic background radiation, nor is the “cold dark spot.” The authors suggest that these are merely spurious artifacts of this masking process. This finding (along with the earlier Planck team's finding of no “dark flow”) pretty much means that the main parts of Mersini-Houghton's “evidence for another universe” have dissolved like the morning mist on San Francisco Bay.

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