Classic Science's Basic Take on the Cosmos:
Everything started 13.7 billion years ago when the entire universe materialized out of nothingness. All structures and events are created entirely randomly, given the four fundamental forces and a host of other parameters. Life began 3.9 billion years ago on Earth, and possibly elsewhere at unknown times. It too occurred by the random collisions of molecules, which in turn are made of combinations of the 92 natural elements. Consciousness or awareness arose out of life in a manner that remains mysterious.
Classic Science's Answers to Basic Questions:
How did the Big Bang happen? A: Unknown
What if anything existed before the Big Bang? A: Unknown
How did life arise? A: Unknown
What is the nature of consciousness? A: Unknown
Why are the forces & constants the way they are? A: Unknown
Is life experienced after one's body dies? A: Unknown
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This is the bare-bones of this interesting article.
And, here are answers to (most of) the above questions, using Urantia Book teachings:
How did the Big Bang happen?
8:1.1 In the eternity of the past, upon the personalization of the Infinite Spirit the divine personality cycle becomes perfect and complete. The God of Action is existent, and the vast stage of space is set for the stupendous drama of creation—the universal adventure—the divine panorama of the eternal ages.
8:1.4 The God of Action functions and the dead vaults of space are astir. One billion perfect spheres flash into existence. Prior to this hypothetical eternity moment the space-energies inherent in Paradise are existent and potentially operative, but they have no actuality of being; neither can physical gravity be measured except by the reaction of material realities to its incessant pull. There is no material universe at this (assumed) eternally distant moment, but the very instant that one billion worlds materialize, there is in evidence gravity sufficient and adequate to hold them in the everlasting grasp of Paradise.
What if anything existed before the Big Bang?
2:1.5 No thing is new to God, and no cosmic event ever comes as a surprise; he inhabits the circle of eternity. He is without beginning or end of days. To God there is no past, present, or future; all time is present at any given moment. He is the great and only I AM.
How did life arise?
36:0.1 LIFE DOES NOT originate spontaneously. Life is constructed according to plans formulated by the (unrevealed) Architects of Being and appears on the inhabited planets either by direct importation or as a result of the operations of the Life Carriers of the local universes. These carriers of life are among the most interesting and versatile of the diverse family of universe Sons. They are intrusted with designing and carrying creature life to the planetary spheres. And after planting this life on such new worlds, they remain there for long periods to foster its development. Also, see our topical study on LIFE
What is the nature of consciousness?
See: Reality of Human Consciousness
Why are the forces & constants the way they are?
42:1.5 The creation of energy and the bestowal of life are the prerogatives of the Universal Father and his associate Creator personalities. The river of energy and life is a continuous outpouring from the Deities, the universal and united stream of Paradise force going forth to all space. This divine energy pervades all creation. The force organizers initiate those changes and institute those modifications of space-force which eventuate in energy; the power directors transmute energy into matter; thus the material worlds are born. The Life Carriers initiate those processes in dead matter which we call life, material life. The Morontia Power Supervisors likewise perform throughout the transition realms between the material and the spiritual worlds. The higher spirit Creators inaugurate similar processes in divine forms of energy, and there ensue the higher spirit forms of intelligent life.
Is life experienced after one's body dies?
146:3.7 “Every earth child who follows the leading of this spirit shall eventually know the will of God, and he who surrenders to the will of my Father shall abide forever. The way from the earth life to the eternal estate has not been made plain to you, but there is a way, there always has been, and I have come to make that way new and living. He who enters the kingdom has eternal life already—he shall never perish. But much of this you will the better understand when I shall have returned to the Father and you are able to view your present experiences in retrospect.”
147:3.3 Verily, verily, I say to you: He who hears the gospel of the kingdom and believes in this teaching of sonship with God, has eternal life; already are such believers passing from judgment and death to light and life. And the hour is coming in which even those who are in the tombs shall hear the voice of the resurrection.”