Re: Can light exist without a source?

The question: Can light exist without a source? My religious studies coursework is 'Is christainity's account of creation reconcilable with science?' Light was made on the first day, but there was no sun or stars (light sources) until the fourth day. Can light exist independantly of a source? Thank you.

You are perhaps aware that most astrophysicists think that some variation of the "big bang" theory best explains what is observed about the universe. The best (by concensus of most astrophysicists) theory is the "inflationary big bang" model about which you have maybe heard. In that model all energy and matter and time came in to being at a moment in time about 13.7 billion years ago. Timelines of the evolution of the universe following that moment can be found in many places, such as this timeline at Wikipedia. Following that timeline you will see sections labelled "Matter Domination" and "Recombination". In the epoch labelled "Matter Domination" atomic nuclei (mostly hydrogen), electrons, and photons (light) existed in more or less equal quantities, but things were so close together and so hot that no photons could travel very far without being absorbed (and then re-emitted) by the electrons. At about 300,000 years after the big bang things had cooled off enough that the nuclei could begin to combine with the electrons to form stable (and electrically neutral) atoms, at which time photons were more or less free to stream through space. It is these photons that are currently detected as the cosmic microwave background. The "light source" was the still-very-hot gases (mostly hydrogen). It was later, after stars and gas clouds had coalesced, that more visible photons started to be produced. But light has been around since the beginning.

You will find different opinions among theologians (and scientists who think about these things) about which event constitutes the "and let there be light" event. Photons have existed from the start of the universe, so there is nothing wrong with calling the moment of the "big bang" the moment of "let there be light", but also nothing wrong with calling the epoch of recombination the "let there be light" moment.

Your main question, "Is Christianity's Account of Creation Reconcilable with Science?" is a much deeper subject, and the answer depends on which type of "Christianity's Account" you discuss. Perhaps your studies can include both of the two major views: "Young-Universe Creationism" and "Old-Universe Creationism". "Young-Universe Creationism" is the view, held by many many Christians, that the universe was created in six 24-hour periods about 10,000 years ago (more or less), and flies in the face of what we know by science about the universe. But "Old-Universe Creationism" supports, rather than opposes, our scientific understanding of the universe. In this sense, then, "Young-Universe Creationism" is not reconcilable with science, but "Old-Universe Creationism" is. You will also find that those who hold to "Young-Universe Creationism" believe in a very convoluted type of "science" that tries to reconcile the differences between their view of creationism and what most scientists call science, but the "reconciliation" does not convince most scientists.

You can find more information about the two Christian views at places like Old Universe: this page of FAQ at RTB and Young Universe: this page of FAQ at ICR.

Despite the fact that RTB has developed a testable model of creation, you will find resistance by scientists to "Old-Universe Creationism", too. The major point of dispute is the difference between views of the origin(s) of life, which is the so-called "Creation vs. Evolution" debate. However, a small but growing minority of scientists apparently find the old-universe creation argument to be intellectually more satisfying than the evolution argument, particularly in light of the major problem of the origin(s) of life, but most scientists still hold to the evolutionary side because it does not require the existence of a God.

You have chosen a huge topic! Good luck in your studies!

John Link, MadSci Physicist