Where did gravity come from?
Carson is not asking a superficial question, but a deep one.
You can say, "well, we think that gravity is a result of bent space-time caused by mass".
Ok. But what causes bent space-time to act in such a way as to cause gravity?
Questions about "how" and "why" things happen are impossible to answer without appeal to God.
You can say "well, X, Y, and Z have been observed to occur prior to or in correlation with the event in question" - but you cannot say anything more than that. No matter what you observe, you always have to ask "what caused that?". Regression as infinitum.
The ultimate cause and reason for phenomena that occurs in the universe is out of the realm of secular scientific study. These are questions of metaphysics that only religious answers apply to.
As for evolution and the age of the earth... yes, most scientists do believe in darwinian theory over billions of years. However, there are people with Phd's who do not believe in those things. Here is a list of just a few:
just a few of the Phd's alive today who believe in Biblical creation=
Dr. Nathaniel T. Jeanseon, PhD in cell and developmental biology from Harvard University.
Dr. Vernon R. Cupps, Ph.D. in nuclear physics Indiana University-Bloomington.
Dr. Jason Lisle, Ph.D. in astrophysics at the University of Colorado.
Dr. John C. Sanford, Ph.D. in plant genetics from University of Wisconsin–Madison.
Dr. Georgia Purdom, PhD in molecular genetics from Ohio State University.
Dr. Leo Hebert III, Ph.D. in physics the University of Texas at Dallas.
Dr. Jeffrey Tomkins, Ph.D. in genetics from Clemson University.
Dr Frank Marsh, Ph.D. in plant ecology from University of Nebraska.
Dr. Danny Faulkner, Ph.D. in Astronomy from Indiana University.
Dr. Russell Humphreys, Ph.D. in physics from Louisiana State University.
Dr. Don Batten, Ph.D. in plant science from the University of Sydney.
Dr. Tas Walker, Ph.D. in mechanical engineering from the University of Queensland.
Dr. Pierre Jerlstrom, Ph.D. in Molecular Biology from Griffith University.
Dr. John G. Hartnett Ph.D. in Physics at the University of Western Australia.
Dr. Jim Mason, Ph.D. in experimental Nuclear Physics from McMaster University.
Dr. Jonathan Safarti, Ph.D. in Physical Chemistry from Victoria University of Wellington.
Dr. Robert Carter, Ph.D. in Marine Biology from the University of Miami.
Dr. Jay L. Wile, Ph.D. in Nuclear Chemistry from the University of Rochester.
so, it is safe to say that a large majority of scientists do believe in evolution and billions of years; there is still a large number (though small in percentage) who dont. you guys can believe whatever you want to believe. but one thing you cant believe is that every educated and intelligent person will agree with you.