Abuse From Other Universes – A Second Opinion


At the end of last year, there was a flurry of activity from astronomers Gurzadyan and Penrose that considered the evidence of alternate universes or the existence of a universe prior to the Big Bang and suggested that such evidence may be imprinted on the cosmic microwave background as bruises of concentric circles. Quickly, this was followed by an announcement claiming to find just such circles. Of course, with an announcement this big, the statistical significance would need to be confirmed. A recent paper in the October issue of the Astrophysical Journal provides a second opinion.

The review was conducted by Amir Hajian at the Canadian Institute for Theoretical Astrophysics. To conduct the study, Hajian selected a large number of circles, similar to the ones reported in the previous studies and asked what the probability was that, randomly, the “edge” of the circles would contain hot-spots, similar to the ones predicted. These were then compared to the bruises reported by the other teams by examining their “variance” which is how much the points on the perimeter were spread around the average temperature.

Hajian notes that, with the resolution considered it would be possible to consider some 5 million circles. The results of his comparison demonstrated that it would be expected that some 0.3% of those should have features similar to the ones reported previously. With so many possibilities, this would imply that some 15,000 potential circles could be flagged as candidates for these cosmic bruises. Even the “best” candidate proposed in the Gurzadyan and Penrose study should still exist statistically.

As such, Hajian concludes that the features Gurzadyan and Penrose reported were not statistically anomalous. Hajian does not comment directly on Feeney et al.’s detection, but given theirs were constructed in a similar manner, it should be expected that they are similarly statistically insignificant. It would appear that if the fingerprints of other universes are embedded in the sky, they have been lost in the noise.

11 Replies to “Abuse From Other Universes – A Second Opinion”

  1. Well, it was the reception of G&P at the time that they didn’t account for the noise but made a simple pattern search. Good to have that validated.

    Hajian does not comment directly on Feeney et al.’s detection, but given theirs were constructed in a similar manner, it should be expected that they are similarly statistically insignificant.

    Maybe they are statistically insignificant, but I don’t think we can expect that given precisely that they go out of their way to test against gaussanity as opposed to G&P:

    “While we didn’t make any clear detections of bubble collisions, we did find four features in the WMAP data that are better explained by the bubble collision hypothesis than by the standard hypothesis of fluctuations in a nearly Gaussian field. We assess which of the two models better explain the data by evaluating the Bayesian evidence for each. The evidence correctly accounts for the fact that a more complex model (the bubble collisions, in this case) will generally fit the data better simply because it has more free parameters. […]

    In addition, using information from multiple frequencies measured by the WMAP satellite and a simulation of the WMAP experiment, we didn’t find any evidence that these features can be attributed to astrophysical foregrounds or experimental systematics.”

    Maybe Feeney et al did it wrongly, maybe not. Meanwhile they (or at least coauthor Johnson) say that their features are on the edge of sensitivity thresholds, and need Planck data to resolve whether they have an observational claim or not.* Among other things polarization data complements the amplitude stuff.

    So I wouldn’t give up on this line of questioning just yet. After all, finding evidences of exouniverses is larger [sic!] than finding evidences of exoplanets.

    * There are several nitpicks to be made here, at least based on Johnson’s description, maybe not the paper:

    – They don’t seem to claim finding or detecting bubble collisions just yet.
    – Their method seems to be open towards the porly constrained bubble collision results. So I don’t think they simply search for “concentric circles”, even if circular symmetry would likely be premiered.

  2. Firstly, the Feeney et al. result is not the same as the Gurzadyan & Penrose effect. The signatures are both circles, true, but not of the same nature at all. That’s one reason Hajian doesn’t mention Feeney in his critique of the G&P paper. Furthermore, the Gurzadyan & Penrose result was *immediately* questioned by three independent groups who put their findings on the preprint server (arxiv.org numbers 1012.1268, 1012.1305, and 1012.1656) within almost the same week. Nobody in the press that I saw hyping this noticed that the astronomy community considered the result a joke. Hajian’s was one of the three critiques. Others were published in peer reviewed journals earlier this year (eg http://adsabs.harvard.edu/abs/2011ApJ…733L..29W and http://adsabs.harvard.edu/abs/2011JCAP…04..033M) So why are you bringing this up once again and once again ignoring or misunderstanding the rest of the literature on the subject? This article shows exactly the same problem as the original hype around this non-result.

  3. the universe is like a fake God of Reality, invented by every life form, and nobody will ever understand its full scope being a barnicle fragment. These concentric rings are merely poor evidence to refute the big-bang theory, and nothing more. Multi-verses could be so distant, that they would leave no trace on the CMB. And if there were multiverses, then everything including the multiverses should be incorporated into what is called the Universe. And if there are multiverses, then there is a larger universe then the big-bang, and more multiverses…. and no ultimate size limits exists, transitory existances, impermance, change, and no God but many fake transitory Gods that die. Viruses or some lower life form eventually kills a God that is superior to its competition, because competition is everywhere in the universe beyond anythings comprehension.

    1. – The search for evidence for other universes are exactly that, and not related to “refuting” big bang theory.

      In one sense there were never a big bang theory to invalidate, because the idea that expansion hits a singularity was never a necessary part of the cosmology labeled “big bang”.

      And in another sense it is already invalidated, since the new inflationary standard cosmology predates the big bang expansion with an inflationary epoch. And modifies the freewheeling big bang expansion with dark energy acceleration, that dominates postdate the middle period.

      Whether you call standard cosmology big bang or not is a matter of taste. It would perhaps be better to acknowledge the difference between earlier cosmologies and the new, open ended on singularities et cetera, but consistent, type of cosmology. But then, famously, we have to wait for the old generation to die. =D

      In a third sense both singularity and multiverse physics is independent of these observations. Here it is inflationary physics as such that needs to be, and can be, constrained by better observations. First Planck, then perhaps even better observatories are needed.

      – As for “competition” there is little of that in the universe.

      For example, biological evolution is nothing but. It is the selection for differential reproduction (fitness) that results in cases of competition and/or coevolution and/or dependence and/or parental care and/or altruism (through inclusive fitness).

      If anthropic selection is correct, it is biological fitness and not competition that “drives” our universe. (Selected for livable parameters.)

      – Finally, none of this is connected to mythology and magic.

      It is pitiful to see over and over again cases of people trying to inject their religion of choice into objective and realistic science as if anyone cared, or manipulated or even _could_ manipulate science for religious reasons. That is fantasies stapled onto fantasies!

      1. This data analysis for cosmic variance could check for non-Gaussian signatures predicted by Gurzadyan-Penrose theory and the eternal inflationary paradigm of Linde et al.. As things stand there is no method for distinguishing one from the other so long as the data is less than 3?. Both of these models are commensurate with big bang, which really refers to the universe in the thermal post inflationary state. The degree of anisotropy of the universe supports inflation somewhat. However, beyond that we are uncertain.

        Smolin has introduced ideas of a sort of cosmic Darwinism, or a selection principle for the scaling of physics in spacetime cosmologies. I will confess that I am not a strong partisan of this idea, but the notion that there is some selection process or “competition” is not completely outside the realm of theoretical physics.


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