Answering the question about if there is physical evidence for God would be difficult without first examining what the nature of evidence is. Basically, evidence is a concept that can fit different categories. Let me explain. Something is evidence if it fits a set of criteria. Criteria are also conceptual because they are a set of standards with which something is judged.So, evidence that someone entered my house and robbed me through the back door would be the footprints in the mud that lead to the back door. A mere set of footprints is not evidence for the robbery unless there is a problem to solve (missing TV) or a phenomenon (disheveled house) to explain and the "facts" that fit the problem. Another kind of evidence would be statistical evidence, expert testimony, an audio recording, documentation, photographs, ballistics, and even something that is not there--when it is supposed to be, like an empty tomb.
Furthermore, when we speak of physical evidence for God we also get into subjectivity. What might be considered sufficient physical evidence for me might not be sufficient evidence for you. So, there again we have another problem. But these are not insurmountable.
We can still ask what kind of physical evidence might we expect of God were real? As a Christian, I would suggest that the universe itself is physical evidence for God's existence since it could not have brought itself into existence and it displays order and design. The cosmological argument for God's existence clearly provides a strong rationale that there must be a personal cause of the universe.
But when we talk about "physical evidence," we are talking about footprints, fossils, fingerprints, broken objects, a dead body, laboratory experiments, etc. And, if we had some so-called physical evidence for God, how would we determine that it is really evidence for God? If the scientific method is used, we have a problem because the scientific method is, by definition, restricted to the physical realm and describes only physical behaviors. But God is not restricted to the physical realm since He is the creator of it. Therefore science would not be the proper method for determining God's existence because it is restricted to the physical realm and the observation of how the physical realm behaves.
Again, what is evidence?
Then again, there's the evidence of objective morals. For example, let's consider the following statement. "It is always wrong for anyone to torture babies to death merely for one's personal pleasure." Is the statement true or is it the case that the statement is not true? If it is true, then it has the quality of universality since it says "It is always wrong for anyone." This is a universal application. This implies universal morals, which imply a universal Moral Law Giver.
Biblical Physical Evidence
Is there biblical evidence? The Bible records examples of physical evidence that God exists.
- Romans 1:20, "For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse."
- Jesus changed water into wine (John 2:6-10).
- Jesus walked on water (Matt. 14:25-27).
- Jesus restored sight to the blind (Matt. 9:27-30; John 9:1-7).
- Jesus' resurrection
- Jesus rose from the dead (Luke 24:39; John 20:27).
These things, and other things like them, would be considered physical manifestations of the work of God that are recorded in Scripture. But, of course, not everyone would accept these as valid. But, if a person's presuppositions do not allow the biblical accounts to be valid evidence, then it will be up to the individual to elucidate what kind of evidence would be acceptable. If the person cannot do that, then perhaps he or she should not ask if there's any physical evidence for God's existence.