Has Cosmic Inflation Been Discovered?
Claims of a major breakthrough about the big bang are swirling in the news: is it inflation, or inflating the evidence?
In “Stop the presses!” style, the science news are simultaneously announcing that gravitational waves have been discovered that reveal evidence for inflation. Cosmic inflation stems from Alan Guth’s proposal in the 1980s that the universe underwent an unbelievable expansion (much faster than light) for just a few billionths of a trillionth of a trillionth of a trillionth of a second immediately after the big bang (see “State of the Cosmos,” 2/21/05). Despite undergoing numerous overhauls and versions, inflation theory has become somewhat of a “given” among cosmologists, because it neatly dispenses with two falsifications of the big bang, the horizon problem and the lumpiness problem. Still, some complained that it was (1) untestable and (2) it created as many problems as it solved. Science Now openly admits the idea sounds crazy:
If imagining the big bang makes your head ache, what happened an instant later might make it explode. Cosmologists think the just-born universe—a hot, dense soup of matter and energy—went through a burst of expansion faster than the speed of light. Like a magical balloon, the cosmos doubled its size 60 times in a span of 10-32 seconds. This phase, known as inflation, ended well before the universe was even a second old.
So how can they suddenly claim that inflation has been discovered?
- Major Discovery: ‘Smoking Gun’ for Universe’s Incredible Big Bang Expansion Found (Space.com)
- First direct evidence of cosmic inflation (PhysOrg)
- First glimpse of big bang ripples from universe’s birth (New Scientist)
- Cosmic inflation: ‘Spectacular’ discovery hailed (BBC News)
- Glimpse of the Universe’s First Split Second Boosts Inflation Theory (Science Magazine)
- Telescope captures view of gravitational waves: Images of the infant Universe reveal evidence for rapid inflation after the Big Bang (Nature)
What really happened is that a team with a sensitive detector dubbed BICEP2 in Antarctica found (they claim) some signals of B-mode polarization in the cosmic microwave background (CMB) – a very weak signal that leans on various models and the ability to identify noise to subtract out. They are interpreting swirls on a chart as evidence of gravitational waves (extremely weak and difficult to detect), which they infer were caused by inflation after the big bang, since producing those artifacts would have required very high energy according to theory. They believe they have ruled out foreground artifacts that might have distorted the signal, but that remains to be confirmed.
Science reporters are going nuts with the announcement simultaneously (showing they are all in cahoots with embargoed news, like horses ready to charge out of the racing gates; this BICEP2 study has been going on for years). Space.com, in particular, is finding creative ways to capitalize on the “spectacular” announcement with advertisement-cluttered video clips, interviews, photo galleries and infographics, obviously prepared in advance for the big publication day.
Deeper reading shows it might be appropriate to hold the horses.
First of all, the experiments are highly theory-laden. It’s a bit like reasoning, “Major premise: If space aliens visited Mars, they would have left faces. Minor premise: a face has been found on Mars. Conclusion: Space aliens visited Mars.” Only if cosmologists assume certain things about what inflation might do to the cosmic microwave background can they claim inflation caused what they think they see. This signal, for instance, would have had to be imprinted on spacetime almost half a billion years before the CMB became visible. Confirmation bias is a common problem in science and in everyday life (that’s why Karl Popper proposed falsification as a criterion for science.)
Second, the data are extremely tenuous. Gravitational waves are notoriously weak. Additional support may come from data now being crunched by the ESA’s Planck telescope’s team. But again, interpretations of the reduced data set after signals considered uninformative are tossed out are not free of theory bias. The team is claiming, nonetheless, that the signal is stronger than expected.
Third, even the “discoverers” of the ripples admit it is premature to conclude their favored interpretation (inflation) is correct. Deep in the Space.com article, team leader John Kovac said he expects a lot of scrutiny to follow the announcement. “It’s going to be controversial,” he told Space.com. “We can expect that people will try to shoot at it from every direction, and we invite that — that’s the scientific process, and it’ll be fun and interesting.” The honest reporters are cautioning their claims with the disclaimer, “If it is confirmed…”. Mr. Inflation himself, Alan Guth, warned in the New Scientist article, “No experiment should be taken too seriously until there’s more than one that can vouch for it.” Nevertheless, some are seeing John Kovac on track for a Nobel Prize.
Fourth, the announcement does not claim to bring understanding of any physical cause for the signal. Harvard cosmologist Avi Loeb gives this admission at the end of the Space.com article:
Still, there is much more to learn about our universe’s first few moments. For example, astronomers still have no idea what the substance that propelled inflation — dubbed the “inflaton” — actually is, Loeb said.
“It’s not yet a victory of theoretical physics that we see evidence for a process that took place early on,” he said. “We really need to understand what this substance — this inflaton — is. And until we do that, it’s just like dark matter or dark energy — we give it a name, but we don’t know what it is.“
Perhaps it is best to summarize the announcement thus: A very tiny signal of uncertain origin might have been detected from the Earth’s surface in microwaves that might have originated in gravitational waves from deep space, but confirmation is needed. Some cosmologists have pet theories, but nobody understands what they mean.
Update 3/19/14: For Evolution News & Views, Rob Sheldon has analyzed the motivations behind this announcement, as well as its physical claims.
Ignoring for a moment the press’s propensity to leap onto bandwagons and toot foghorns in unison, let’s consider what this announcement means for creationists. If the signal turns out to be real and did come from gravitational waves during the birth of the universe, why should they be surprised? They believe God stretched out the heavens in the mighty miracle of Genesis 1:1, “In the beginning, God created the heavens and the earth.” Why wouldn’t a supernatural event like that leave footprints in natural signals? If we are on the frontier of gravitational wave astronomy, praise the Lord! We can learn some more things about creation.
Oh, but naturalists argue, we have science, so we don’t need miracles to explain the universe. Oh, yes they do. Consider: they don’t know what inflation is, they don’t know what an inflaton is (it’s just a name to cover ignorance), they don’t know what triggered the big bang, they don’t know what came before it, they invented inflation to avoid falsification of their naturalistic theory. Inflation creates as many problems as it supposedly solves, because it merely transfers the extreme-low-entropy initial conditions of the big bang to inflation itself. Moreover, it was a one-time event, with no explanation, that occurred under no known laws of nature – ruling out the principle of uniformity, the basis of science. Conclusion: inflation is tantamount to a miracle. Q.E.D. So: everyone believes in miracles. Christians have all the reason to believe that intelligently-designed miracles are superior to mindless miracles of chance, especially when they result in human brains capable of asking questions like this.
This announcement, therefore, gives no support to naturalism. All the problems that existed before are still there. Guth admitted in 2005 that inflation, which he called a “collection of models rather than a unique theory,” does not remove the Anthropic Principle – an idea that he confessed sounds patently religious. This announcement is just the latest case of philosophical naturalists and their toady reporters inflating a nanometer into a light-year, claiming far more than they can possibly know, using minds that, by attempting to employ laws of logic, refute their own naturalistic premises.