In a word, no!
I think we all have at least three very good reasons for thinking there is more to reality than physics: (1) Our thoughts and feelings do not seem to be physical things. (2) The “values” of things–their goodness, badness, rightness, or wrongness–do not seem to be physical. And (3) considering why physical things exist in the first place can make us suspect that they’re ultimately caused by something non-physical.
Our thoughts and feelings are no doubt largely caused by physical things going on in our brains. Our thoughts and feelings seem to correlate perfectly, in fact, with chemical and electrical events in our brains. And these events are all a matter of physics. Nevertheless, what we feel and what we experience when those physical things are going on in our brains do not seem to me to be physical things. Our thoughts and feelings themselves are not the sorts of things that physics studies. (When “materialists,” or “physicalists,” say that everything is physical, what they mean is that everything that really exists is [or is entirely composed of] the sort of thing that physics studies.) Thoughts and feelings are plainly real. But they do not seem to be physical things in this sense. I doubt very much, then, that everything real is physical.
I have at least two reasons for thinking that thoughts and feelings are not physical. First, they do not seem to have the same kinds of characteristics as physical things; they do not have a size, shape, weight, or electrical charge, for example. Secondly, if our thoughts and feelings were physical things, the only physical things they could plausibly be would be the physical things going on in our brains when we’re having those thoughts and feelings. Studying the physics of those physical brain states and events, however, can never tell us “what it feels like” or “what we experience” when our brains are in those states. Only people who have had those experiences can tell us what they feel. “What we experience,” therefore–the thoughts and feelings themselves–must be something other than the physical goings-on in our brains. Though our thoughts and feelings do correlate with physical states and events in our brains, they must not be the same things as those physical things. I don’t see how they could be physical things at all.
The values of things–their goodness or badness, or rightness or wrongness–also seem to me to be another non-physical aspect of reality. Some things are good. Others are bad. Some actions are right. Others are wrong. It is part of reality that situations and actions have these characteristics. But this is not something physics will tell you. These characteristics are not physical characteristics. They are not like color, or weight, or size, or speed; they are not the sort of characteristics physics analyzes at all. They may correlate with various physical characteristics, but they are not physical characteristics themselves. These “values” of things, then, seem to constitute another non-physical aspect of reality.
Some people, taken with the idea that all of reality is physical, actually end up denying that these values are a real, objective aspects of reality. They say that goodness, badness, rightness, and wrongness are all just part of an illusion or myth in our minds. Or they are just a matter of how we feel about things. Think for yourself about this, however. Is torturing children really wrong and bad? Or is our thinking that it is just a myth, an illusion, or a matter of how we happen to feel about it? And wouldn’t torturing children still be wrong even if we all thought it was just fine? I doubt you really think otherwise. The values of things, then–their goodness, badness, rightness, or wrongness–seem to be another very real, but non-physical, aspect of reality.
The third thing that at least makes me suspect that there is more to reality than physics is this: If we ask why there are physical things at all–why there are any of the things physicists analyze–I can think of only three semi-plausible ways the question could be answered. Either (1) there is no explanation, or (2) physical reality has to exist, for some reason, or (3) something else, something(s) nonphysical, caused it.
It’s pretty hard for me to buy the idea (1) that there literally is no explanation why physical reality exists. Even if we don’t know what the explanation is, surely there is one. Surely there is some reason why the physical universe exists. It also strikes me as unlikely that (2) physical reality has to exist for some reason. I know of no plausible reason why it would have been impossible for there to be no physical universe at all. It seems quite plausible to me, on the other hand, that (3) this physical universe could have been caused by something else–caused by something of a different sort. (Since nothing can cause itself, if there is an ultimate cause of everything physical, that cause would have to be something non-physical.)
These considerations, and others, make me think it highly unlikely that all of reality is physical. Some plainly-real things (like thoughts, feelings, and values) just don’t fit into physics. It also seems likely to me that the physical world has a non-physical cause.