Again, I understand the analogy but it's not 100% suitable for describing the creation of the Trinity purely because we know that the light is literally created this tiny fraction of a moment after the source of light comes to existence. And alternatively, the light might still exist even after it's source ceased to do so (many stars we see is in fact just the light they produced as they are already dead). To apply this analogy to the Trinity we would have to accept that there was a moment when there was only the Father.The sun is not a lightbulb. I'll repeat then flesh out what @MichaelWitcoff said, The sun cannot exist without giving off light, and sunlight cannot exist apart from the sun which causes it. If it does not give off light, then it's not a sun. If the sun ceased to give off light, then it wouldn't be the sun anymore. It may have used to be a sun, but it is not a sun anymore. Objects require properties for their existence, without those properties they cease to be the same thing. If you throw a chair into a fire, is it still a chair? or would you describe is as a pile of ashes? Is a hole still a hole if it's been filled?
@MichaelWitcoff read my previous post on page 8, Dr Johnson/Fr. Raphael believes that St. Augustine is misinterpreted.