The physical world? No. I think that is obvious to the author however. This is not about the physical world but about Israel. He is claiming that Israel has made plain God's invisible qualities.Here are two translations of Romans 1:20 from the same website:
Therefore, this thread is open to anyone, but I wanted to ask the question: Do you think that God's invisible qualities have been clearly seen from what has been made since the creation of the world or not? And I'm looking for answers coming from the viewpoint of if there is a God, whether you believe there is or not. Also, I put this thread in Science and Religion Debate because I felt that scientific answers would eventually arise in this discussion. Plus, if you don't mind, I'll let someone else start the conversation off first.
in John 17 Jesus says in his prayer "I have revealed you to those who..." This might seem confusing since I just said it was through Israel but this has to do with the way the New testament treats Jesus as the expression of Israel perfected through 42 generations and the exact representation of God's being. It is theological not physiological. Israel (in scripture) is a moral institution, even with no land, no king and no army. Romans 1:20 takes the position that Israel has fulfilled its purpose in revealing God's hidden qualities.
Your question cannot be properly treated in the science versus creationism section, because it is automatically framing the question as being about the physical world which it is not about.
Perhaps you have got a good reason to think that it is about the physical world? That would be problematic. The author has just finished stating that God's qualities are invisible. In addition if Genesis is a literal account of the physical creation of our world (which I do not support) then God's qualities were never invisible contrary to Romans 1:20. In the wrong context the verse is meaningless.
It makes much more sense for Paul to be talking about Israel which is styled a creation in Psalms if not in other places. There also are plenty of scriptures (in the Christian NT) which talk about Israel revealing God's qualities. For example Jesus says "you are the light of the world" and Jesus says "you're the salt of the earth."
Theologically the verse is emptied of meaning, because it doesn't matter how the physical world was created. All that matters to the author is the glory revealed through Israel and/or through Jesus. That is the only creation they could possibly be talking about.