THE USM SOUTHWORTH PLANETARIUM
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70 Falmouth Street Portland, Maine 04103
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Founded January 1970
Julian date: 24581539.5
Sunrise - 5:32 a.m. Sunset - 7:44 p.m.
THE DAILY ASTRONOMER
Tuesday, May 1, 2018
Before the Big Bang!
Yes, we know what we said!
We know we claimed that the question, "What was before the Big Bang?" was an unaskable question, tantamount to asking, "What is one degree north of the North Pole?" or "What does Friday smell like?" Any question pertaining to conditions prior to the Big Bang were deemed nonsensical because the word "before" is temporally relative. The prevailing cosmological theory -the Big Bang- insists that the Universe was born in a singular event that occurred approximately 13.8 billion years ago. As this genesis event created time itself, no moments could have preceded it. Immediately after this "bang," the Universe inflated rapidly and then decelerated to a much slower expansion rate. This rate is now accelerating with time due to the influence of the still mysterious "dark energy."
Many cosmologist subscribe wholeheartedly to this notion. Now, however, the preeminent Oxford mathematical physicist Dr Roger Penrose believes that the Big Bang was not the beginning. In fact, Dr. Penrose's recent ruminations have compelled him to conclude that the Universe is born and re-born through an "infinite loop," with no definite beginning and no foreseeable end. Iterations to the nth degree. According to his admittedly controversial theory, what preceded the Big Bang was an entire life cycle of the previous Universe, which, itself, formed from the prior one, ad infinitum. Each Universe, by Penrose's definition, is called an "aeon," and he has dubbed the theory "Conformal Cyclic Cosmology."
The basic idea involves "entropy," the tendency of the Universe to greater states of disorder. Initially, the entropy would have been extremely low: a high degree of order that cannot be reconciled with inflation's rapid expansion. Thermodynamically, entropy increases inexorably with time: or, Chinua, things fall apart. However, in the very distant future, the entropy will decrease through black hole evaporation. Information drawn into a black hole is lost forever. All black holes "eventually" evaporate through emission of Hawking radiation. These evaporations literally reduce entropy and thus, in the extreme remote future, the cosmos will assume a low entropy state similar to that of the early Universe. The attainment of this low entropy state will permit the initiation of the next aeon, or Universe. That, itself, will experience entropy increase until such a time when black hole evaporation will return it to the low entropy state again.
Conformal Cyclic Cosmology is not merely high level mind play, but, Dr . Penrose believes, is substantiated by recent observations of the Cosmic Microwave Background Radiation (CMBR.) The CMBR is the 2.7 K* radiation pervading the Universe, and is generally described as the Big Bang's echo. Created about 300,000 years after the Big Bang, when the Universe was still furiously hot, the radiation cooled down to today's 2.7 level as a result of this expansion. NASA's Wilkinson Microwave Anistropy Probe (WMAP) has surveyed this background and detected 'concentric circles,' within the CMBR: essentially specific regions in which the temperature is lower than the surrounding areas. According to the inflationary theory, which Penrose now disputes, such temperature variations should be random, and not concentrated on specific areas. Penrose describes these well defined regions as being similar to 'scars' produced in our 'aeon' by colliding black holes in the previous aeon. Such collisions produce such unfathomable energies that the resultant gravity waves could leave an imprint in an aeon subsequent to the aeon in which the collision occurred.
Despite the challenges that Dr. Penrose has offered to the standard cosmological model, the Big Bang has not yet been discarded. Many eminent cosmologists haven't wavered from their contention that the Big Bang marked the definite beginning of the cosmos. Moreover, scientists seeking a definite resolution to the creation problem consider Conformal Cyclic Cosmology unsatisfactory, as it doesn't answer the question of reality's inception. It merely photocopies it.
We do know that the question "What came before the Big Bang?" might no longer be unaskable. Instead, it joins the myriad other questions that remain unknown.
*K = kelvin. 0 K is "absolute zero," a theoretical lowest temperature limit at which all motion ceases. 2.7 K is 2.7 "degrees above absolute zero, (Note If you read 2.7 K as "2.7 degrees Kelvin." an eagle will gnaw on your liver. The proper phrasing is "2.7 Kelvin."