John Lennox is another of my favorite Christian apologists.  He is Emeritus Professor of Mathematics at the University of Oxford and an Emeritus Fellow in Mathematics and Philosophy of Science at Green Templeton College, Oxford University.

In this 2011 film clip (https://www.youtube.com/watch?v=UIknACeeS0g), which is just over 10 minutes long, Dr. Lennox discusses the question, If God created the universe, then who created God? and the question, How can God be a triunity?

Lennox tells of an occasion on which he addressed a convention of scientists.  Afterward, a member of the audience approached him and asked whether it was possible that Lennox should actually subscribe to such an irrational doctrine as that of the Trinity.  Instead of answering immediately, Lennox asked him a question of his own.

Do you believe in consciousness?  Energy?  (Yes.)  Do you know what they are?  (No.)  Should I write you off as an intellectual for believing in something you don’t understand?  (No.)  That’s what you were going to do to me five minutes ago.  Why do you believe in them?  (Lennox supplies the answer:) Because of their explanatory power.  A trinity is the only explanation that makes sense of the evidence as Lennox sees it.  God Himself is a fellowship.

What is it that a divine fellowship explains?  Many things, I’m sure; but perhaps principally it answers the question, How can God be love, if in eternity past, prior to creation, there was no one around for Him to love?  The doctrine of the Trinity explains that God has never been alone, but that each Person of the Trinity has eternally been in the most intimate fellowship with the other two Persons.  Thus, the doctrine of the Trinity explains how it is that God is love.

Do yourself a favor and introduce yourself to this wonderful man.  For further reading, see God’s Undertaker: Has Science Buried God? (Lion 2009) and God and Stephen Hawking: Whose Design is it Anyway? (Lion 2011).