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Before the Big Bang

  1. Aug 18, 2009 #1
    I was watching "The Universe" on History Channel today and it was asking the quesiton, "what was before the Big Bang and what triggered it?" Unforunately, I had to leave and could not finish watching it. Could someone shed some light? Even if you didn't see it, could you please fill me in?
    Last edited: Aug 18, 2009
  2. jcsd
  3. Aug 18, 2009 #2


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    What conditions led up to the start of expansion is not yet known. There are some models of how it could have happened. And I expect the models will eventually make testable predictions (of consequences we can look for and either observe or not.)

    I don't trust TV science programs, though. They can give the impression that something is definitely known when it is still just a conjecture or untested hypothesis. You might want to take a look at the Einstein-Online website's stuff on cosmology. It is the public outreach effort of a top research institutions. Have a look at "A tale of two big bangs", which helps to clarify what is meant by the term, depending on context.
    http://www.aei.mpg.de/einsteinOnline/en/spotlights/cosmology/index.html [Broken]

    A book is scheduled to come out next year, from Springer, a German publisher, which deals with current thinking about this. It is called Beyond the Big Bang.
    It has essays by some 20+ leaders in early universe cosmology.
    Some 600 pages. If you are curious you might see if your local library will order the book, when it comes out.

    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4?detailsPage=reviews [Broken]

    Table of contents:
    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4?detailsPage=toc [Broken]

    General description by publisher:
    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4 [Broken]

    "The Big Bang model is now both theoretically and empirically well established. However, the very beginning of our universe still remains mysterious. General Relativity breaks down at very small spatio-temporal scales and at high energy densities. That is why Quantum Cosmology is needed. Recent developments open up the exciting new prospect of going 'beyond' the Big Bang and even finding a physical explanation for it. Surprisingly, the ancient idea of a past-eternal universe is being revived, and fascinating new approaches are also being developed. This book provides an up-to-date overview of the competing scenarios in cosmology and discusses their foundations, implications, and philosophical aspects. It gathers original contributions from the world's leading researchers in Quantum Cosmology, who describe their own work and results in a manner understandable even to non-specialists."

    You will see that Cosmic Darwinism (which you asked about in another thread) is included as one of the chapters listed in the Table of Contents.
    Last edited by a moderator: May 4, 2017
  4. Aug 18, 2009 #3
    I want to mention the Universe before the Big Bang: Cosmic Microwave Background Radiation Anisotropies: their Discovery and Utilization, Nobel Lecture, December 8, 2006 by George F. Smoot. I present only two snippets from the his lecture:

    1. "The Cosmic Background Radiation Observations of the Cosmic Microwave Background (CMB) temperature anisotropies have revolutionized and continue to revolutionize our understanding of the Universe. The observation of the CMB anisotropies angular power spectrum with its plateau, acoustic peaks, and high frequency damping tail have established a standard cosmological model consisting of a flat (critical density) geometry, with contents being mainly dark energy and dark matter and a small amount of ordinary matter. In this successful model the dark and ordinary matter formed its structure through gravitational instability acting on the quantum fluctuations generated during the very early Inflationary epoch. Current and future observations will test this model and determine its key cosmological parameters with spectacular precision and confidence."

    2. "According to Big Bang theory, our universe began in a nearly perfect thermal equilibrium state with very high temperature. The universe is dynamic and has been ever expanding and cooling since its birth. When the temperature of the universe dropped to 3,000 K there were insufficient energetic CMB photons to keep hydrogen or helium atoms ionized. Thus, the primeval plasma of charged nuclei electrons and photons changed into neutral atoms plus background radiation. The background radiation could then propagate through space freely, though being stretched by the continuing expansion of the universe, while baryonic matter (mostly hydrogen and helium atoms) could cluster by gravitational attraction to form stars, galaxies and even larger structures. For these structures to form there must have been primordial perturbations in the early matter and energy distributions. The primordial fluctuations of matter density that will later form large scale structures leave imprints in the form of temperature anisotropies in the CMB.”

    And some added information from Massachusetts Institute of Technology, Technology Review’s article, Nobel Causes, Cell biology and cosmology will never be the same, thanks to Andrew Fire, PhD ‘83, and George Smoot ‘66, PhD ‘ by Katherine Bourzac, January 12, 2007:

    "He [George Smoot] co-led the research team behind NASA’s COBE satellite, which made the first quantitative measurements of the initial conditions of the universe. Smoot’s 1992 map of tiny temperature variations in cosmic radiation originating from about 14 billion years ago is the big bang theory’s smoking gun. The minute fluctuations Smoot charted are thought to indicate the local concentrations of energy–the “seeds”–around which matter coalesced into the clusters of galaxies that make up today’s universe”. “(p.1)

    And, from the same article, "Astrophysicists say Smoot and Mather’s announcement of COBE’s results was a turning point for cosmology, when philosophical speculation about the universe’s origins gave way to a science built on quantitative evidence. Smoot’s map was subsequently verified by further balloon experiments and has since been enhanced by more sensitive measurements from WMAP, a NASA satellite still in orbit. Bertschinger likens Smoot and the other COBE scientists to explorers finding new continents. “You first find the continents and then explore the coastlines and make your maps more and more refined,” he says.” (p.5)

    p.s. I posted earlier today the same information on Scientific American Magazine's article, The Origin of the Universe, and earlier this month to Smashing Magazine's article, Stunning Space Photograpy. I derive great inspiration from science and technology which is the expert guide to unlocking the majesty and beauty of the Universe we live in. :biggrin:
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