Out from Princeton Press.
Probably the toughest questions an astronomer ever has to field with the public are those in cosmology. How old/how big/how far are truly mind bending questions, and difficult to explain to the average man on the street in sound-bite style. This week, we look at David Weintraub’s latest, How Old is the Universe? out by Princeton Press. Fans of this site will remember our review of Is Pluto a Planet? also by Mr. Weintraub a few years back.
How Old is the Universe? Serves as an address on the state of cosmology today, and how we’ve accumulated our knowledge up to this point and what it says about our present and future. Its premise is a simple one; a basic question of the age of existence and the ramifications that it implies. A field such as cosmology builds on evidence-based suppositions; the author starts with how we know the age of the Earth, Moon and bodies in the solar system and how this puts rough constraints on the lower age limit of the cosmos. You can’t be older than your parents by definition, and objects in the universe cannot be older than the universe itself.
Cosmology has rapidly moved in the last century from the realm of philosophy to one of science. Imagine; the universe of our grandparents consisted of the Milky Way, with a few dim smudges on a photographic plate that defied description. Edwin Hubble blew the doors off of that in the 1920’s, showing that our galaxy is but one in the cosmos. And our great-grandparents had the formidable task of measuring the stellar parallax, using nothing but windup time pieces and wire transit micrometers and a sharp eye… the road to modern cosmology has been a tough one indeed.
Universe climaxes with another quiet watershed moment of the 20th century; the discovery of the Cosmic Microwave Background radiation (CMB) by Penzias & Wilson in 1964. Here is science at its best; a surreptitious discovery of a prediction made by theory.
The author also covers other points of evidence that builds a compelling case for the Big Bang; did you know that the ages of globular clusters fit nicely with the constraints of predictions, or that the temperature/luminosity of white dwarfs suggests a lower limit to the age of the universe? Or that the Hubble constant has been narrowed down considerably in the past few years, or that the ratios of lithium, deuterium and even the very existence of such elements as boron suggest that the Big Bang had to occur and the the resulting universe was non-homogeous? Universe covers all of this and more, looking at the compelling questions of modern cosmology; is the universe open, flat or curved? What is dark energy? Where is a majority of the universe (aka dark matter) hiding? These are questions we may just see answers to in our lifetimes.
The horn antenna that discovered the CMB…(Credit: NASA/Bell Labs).
Read How Old is the Universe? To get a compelling look at a fundamental question. The cosmological questions are always the toughest to answer, as our knowledge stacks one careful cornerstone after another. It seems that after evolution and climate change, the Big Bang Theory stacks up as public enemy no. 3 in the theories that the anti-science crowd wants to knock down. It’s strange that this should be so; most creation tales start with a finite beginning, a “let there be light” moment that jibes well with what modern cosmology tells us, if you allow for a modicum of allegory… in our minds, a steady state universe would be more bizarre. Read Mr. Weintraub’s work to arm yourself with the best reply, that of knowledge and wonder at the universe we all inhabit.