No, we are not. We are living on a planet that came together 4.5 billion years ago in a universe that began 15 billion years ago. There is no more evidence of us being delusions of a god than there is of us being a computer simulation. Look out of your window; all the stuff out there is real. Fanciful thoughts about us being a delusion or computer simulation or existing in a cell on the back of a giant space rabbit are just that; fanciful thoughts.
We can test the theory that gods exist; for example the Christian one that many deluded people are enthralled with, this fellow promises prayers will be answered. They never are. Not once.
One life is all we have. Enjoy it and experience it before we return once more to eternal sleep. Don't waste it on imaginary magicians.
The idea that the universe exists as something other than information is called Objective Reality Theory (ORT). ORT states that objects exist continuously and that they are self contained or self existent, i.e. that following the big bang, objects don't depend on anything outside of the universe for their existence. This idea that the universe is continuous and self contained/self existent is completely unproven as are all metaphysical claims at the present time. However, ORT is a positive claim that is hypocritically regarded as a null hypothesis.
You mentioned a computer simulation, which happens to be a very good analogy for the mechanics of the dream of God that is the universe. My belief is that objects are discontinuous, meaning that they are generated anew each Planck time, similar to the refresh rate on a computer monitor and that they do not exist in and of themselves but are the output of nonphysical quantum processing, this processing being the deluded aspect of God that is dreaming the universe.
It is common knowledge and taught in all Quantum Mechanics 101 courses that, via the Schrödinger equation, it is possible for a billiard ball to tunnel to any point in space due to its wave function. The probability of a billiard ball tunneling through a wall or other solid object is extremely small but no scientist would deny that it is entirely POSSIBLE for a billiard ball to tunnel through a wall. This possibility is mentioned in the Wikipedia article on the Schrödinger equation in terms of a ball tunneling through a hill:
"In classical physics, when a ball is rolled slowly up a large hill, it will come to a stop and roll back, because it doesn't have enough energy to get over the top of the hill to the other side. However, the Schrödinger equation predicts that there is a small probability that the ball will get to the other side of the hill, even if it has too little energy to reach the top. This is called quantum tunneling. It is related to the uncertainty principle: Although the ball seems to be on one side of the hill, its position is uncertain so there is a chance of finding it on the other side." https://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation#Quantum_tunneling
In my opinion, the reason it is possible for a solid object such as a billiard ball to pass through another solid object such as a wall or a hill is that all objects have a refresh rate of one instance each Planck time. Normally, these instances are generated in accordance with the laws of classical physics but it is possible, due to a glitch, that classical physics can be superseded by quantum mechanics. A billiard ball can 'seemingly' pass through a wall if one instance of the ball is generated on one side of a wall and the next instance of the ball is generated on the other side of it. The appearance is that a self existent/continuously existing object has passed through another but this is not what is actually happening. If it were not for reality being a discontinuous processing output, quantum tunneling, or the superseding of classical physics by quantum mechanics in macro sized objects would not be possible in my opinion.
You seem to be suggesting that I can learn something about the nature of reality by looking out of my window, or by stubbing my toe on a coffee table, as if is our experience and common sense is a good indicator of metaphysical reality. I disagree. In the ancient world, the earth was regarded as flat due to experience and common sense. If anyone suggested the earth was a sphere it was laughed at. "How would the water stay in the lakes, why wouldn't we fall off the earth etc.?" A flat earth made the most sense and had the least number of assumptions for what they knew at the time. It was the model that best followed Occam's razor to explain observed phenomena of the day, such as water staying put in lakes. However, with advances in Hellenistic astronomy, the flat earth model was no longer the best model to explain observed phenomena with the least number of assumptions, hence a new model was needed, that of a spherical earth.
Similarly, Objective Reality Theory is not the best model to explain phenomena related to quantum mechanics and relativity. Virtual Reality Theory explains these things better, with far fewer problems. By VRT I am not referring to anything about God, VRT is a valid scientific theory comparable with something like Hugh Everett's Many Worlds Theory. In VRT, the processing that generates our universe could be entirely naturalistic. VRT is not dependent on any belief in a deity, though I personally happen to have such a belief.
If you are interested in learning something about the Virtual Reality argument rather than just dismissing it out of hand as 'fanciful thoughts," I recommend Brian Whitworth:http://brianwhitworth.com/VRConjecture.pdfhttp://brianwhitworth.com/VRTQuestions.pdfhttp://brianwhitworth.com/BW-VRT1.pdfhttp://brianwhitworth.com/BW-VRT2.pdfhttp://brianwhitworth.com/BW-VRT3.pdf
The problem being, this doesn't work as an explanation unless you think only one human is real, or (much more likely) unless you think that this sleeping god's personality is so fragmented that he can run literally billions of individual 'fragments', each literally thinking they're a unique individual, in this dream. That goes way beyond schizophrenic, not to mention the multiple personality thing.
Yes, the delusional, dreaming aspect of God is completely schizophrenic with severe multiple personality disorder. I am not joking. This is my actual belief. The God I believe in is imperfect.