One of creationists’ pet arguments is “fine tuning”, meaning that the physical constants of the universe are so meticulously “adjusted”, they must have been set by an intelligent entity (that being the Abrahamic god, of course) such that the universe can support life. I have discussed this argument and its shortcomings before; suffice it to say here, it is rather odd that this intelligent entity would create a universe such that it could support life, but at the same time make the overwhelming majority of this universe hostile to life; and even if it were a sensible argument, it still would be evidence of an Abrahamic god, rather, a Tom Paine-style deistic god.
There has been another hypothesis, however, known as anthropic principle. Anthropic principle has two form: “weak” and “strong”.
As it might have been argued that the physical distance of the Earth from sun is so “fine tuned” that it may support life, and yet now we know that with billions of galaxies each harboring billions of stars, finding one with a planet that could support life is all but inevitable; because with infinite possibilities, anything that can happen, will happen. In other words, Earth is friendly to life, because we are here! This is the weak anthropic principle, and by and large it is uncontroversial today.
But what is of interest here is the so called “strong anthropic principle”, grounding the specific combination of the universe’s physical constants in the possibility of many (infinite?) universes, hence stipulating, once again, anything that can happen, will happen. While this has been merely hypothetical (until now), it has drawn the ire of accomodationist physicists-who do not wish to see their religious doctrines undercut by scientific findings (sound familiar?). And some reputable physicists have come up with rather bizarre-sounding(and erroneous) rejoinders such as:
There’s no doubt that the popularity of the multiverse is due to the fact that it superficially gives a ready explanation for why the universe is bio-friendly. Twenty years ago, people didn’t want to talk about this fine-tuning because they were embarrassed. It looked like the hand of a creator. Then along came the possibility of a multiverse, and suddenly they’re happy to talk about it because it looks like there’s a ready explanation. . . Even the scientific explanations for the universe are rooted in a particular type of theological thinking. They’re trying to explain the world by appealing to something outside of it.
OK, it is not like science typically produces ideas because people find them philosophically convenient (unlike religion), but that not withstanding…”theological”? OK, so according to the multiverse hypothesis the origin of universe may be outside of it, but there is still nothing supranatural, or conscious, or all-knowing about it…is this some new kind of theology?
Be that as it may, it now appears that we may have the first physical evidence that the multiverse is actually out there, and not just in our mind: through the study of Big Bang remnant known as the Cosmic Microwave Background.
But now we have the “eternal universe inflation” scenario. It predicts that our observable universe resides inside a single bubble embedded in a vast inflating multiverse of an infinity of other bubbles that are their own unique universes with their own unique set of physical constants. (This would help explain why dark energy is so weak – it is just one flavor of dark energy in the megaverse.)
These parallel universes are popping in and out of existence and colliding all the time, like popping kernels in a popcorn kettle. However, space between the bubble universes is rapidly expanding. This imposes a cosmic quarantine where the universes are out of reach of one another.
But cosmologists are conducting observational tests of eternal inflation. The idea is that our universe should bump into a parallel universe. This would leave a telltale smudge on the cosmic microwave background.
This would happen if there were simultaneous big bangs occurring close together. The baby universes would bump into each other, but the space between the bubbles inflates faster than the speed of light, and so they quickly scatter apart.
The CMB is being mapped by several spaces telescopes, so a snapshot of how the universe looked 380,000 years after the Big Bang is emerging. It is mottled with slight ripples of temperature variations, which were the seeds for the construction of great filaments of galaxies.
A team lead by Stephen Feeney of the University College London ran a statistical program that looked for circular patterns on the CMB from seven-year’s worth of data from NASA’s WMAP satellite. Their program found four particular areas that look suspiciously like the pattern predicted from inflating megaverse theory. But is this just a cosmological Rorschach?
Back in 2004, astronomers studying data from the Wilkinson Microwave Anisotropy Probe (WMAP) found a region of the cosmic microwave background in the southern hemisphere in the direction of the constellation of Eridanus that was significantly colder than the rest by about 70 microkelvin. The probability of finding something like that was extremely low. If the Universe really is homogeneous and isotropic, then all points in space ought to experience the same physical development, and appear the same. This just wasn’t supposed to be there.Ray Zhang and Dragan Huterer at the University of Michigan in Ann Arbor say that the cold spot is simply an artifact of the statistical method–called Spherical Mexican Hat Wavelets–used to analyze the WMAP data. Use a different method of analysis and the cold spot disappears (or at least is no colder than expected).
“We trace this apparent discrepancy to the fact that WMAP cold spot’s temperature profile just happens to favor the particular profile given by the wavelet,” the duo says in their paper. “We find no compelling evidence for the anomalously cold spot in WMAP at scales between 2 and 8 degrees.”
Now, however, scientists have a more advanced tool: European Space Agency’s Planck satellite system.
A few weeks ago, however, scientists published a spectacular new map of the cosmic microwave background – the “radiation” left behind after the Big Bang that created the universe 13.8bn years ago.
The map, based on Planck data, showed anomalies in the background radiation that, some cosmologists say, could only have been caused by the gravitational pull of other universes outside our own.
“These anomalies were caused by other universes pulling on our universe as it formed during the Big Bang,” said Laura Mersini-Houghton, a theoretical physicist at the University of North Carolina at Chapel Hill.
“They are the first hard evidence for the existence of other universes that we have seen.”
Such ideas are controversial but are attracting growing interest among physicists. This is because Mersini-Houghton, and her colleague Professor Richard Holman, at Carnegie Mellon University, published a series of papers from 2005 predicting what Planck would see.
In particular, they predicted that the ancient radiation permeating our universe would show anomalies generated by the pull from other universes.
The scientists analysing the Planck data have now published a paper acknowledging the anomalies exist and cannot be explained by conventional means. “It may be that the statistical anomalies described in this paper are a hint of more profound physical phenomena that are yet to be revealed,” it said.
Planck worked by gathering radiation from when the universe was just 370,000 years old – still glowing from the Big Bang. It has been travelling across space for 13.8bn years and so is remarkably faint but still detectable. In theory, that radiation should vary a little on the scale of galaxies and clusters of galaxies, but at much larger scales it should be evenly distributed.
In practice, however, Planck’s data shows this is not the case. The radiation is stronger in one half of the sky than the other. There is also a large “cold” spot where the temperature is below average.
While at this time it remains hypothetical, it has to be said that it is a very intriguing one: the multiverse, if confirmed, could be the most “stellar” scientific discovery in history. But there would also be a minor problem, for creationists: first Darwin took biology away from them, and now it seems Holman and Mersini-Houghton are trying to take physics from them.
