Science will never give you certainty, but it can reassure you beyond reasonable doubt, which will have to suffice.
It is interesting that some would feel the need to be reassured (that consciousness does not survive the body)
I don't have a problem with either case. That is likely one reason why 'beyond reasonable doubt' is not sufficient enough. Certainty is sufficient, and you should have gathered that I am not complaining at all that scientists are unable to be certain about this. I have explained already why that is the case. It is not something scientists should be overly interested in as there is no known and accepted scientific method in which to give certainty in answer to the question.
It's not clear what you mean by 'non-physical', but whatever it is, to be relevant to human bodies & brains, it must interact with them in some way; so to that extent it must have physical influence (otherwise you're stuck with the perennial 'interaction problem' or an appeal to 'magic').
By 'non physical' I simply mean 'other than strictly fixed and observable in this universe.' It is something of a concept.
So essentially 'non physical' in that context would have to signify 'unable to presently observe through our physical senses even with present day instrumentation.'
Certainly there are those who have (and do) experience being conscious and not in their body. I myself have experienced going through ceiling and roof. Since both are solid objects then it must have been the consciousness I am which was 'non physical'. Therefore I can extend this to understanding that consciousness is non physical. I am thus non physical even if I am within a physical receptacle, such as the human body.
One can of course observe how consciousness interacts with biological instruments (such as human bodies).
That in itself may well signify relevance to the individual who experiences such. There is certainly interaction therein. The interaction is different, that is all.
I have never read anyone experiencing such, claiming it was 'magic'. I would not consider my own experiences to being 'magic'. Some say it is a '
trick of the brain'...that is the nearest example I can think of which would be an appeal to 'magic'.

It occurs to me (correct me if I am wrong) that the greater percentage of an atom is empty space. Is empty space non physical?
Now if you're prepared to accept that the science behind the microprocessor in your computer, the LEDs in the little lights around the place, the laser in your DVD or Blu-Ray player (and a whole bunch of other technological wonders of the modern age) is a reasonably good approximation of how the world works (and it is - the gadgets work, don't they?), then we can say beyond reasonable doubt that consciousness doesn't continue beyond death.
That is because the same science behind those gadgets tells us that only electromagnetism has the strength, range, and specificity at human scales to interact with the cells, or atoms & molecules of the brain. And electromagnetic fields are measurable and require all kinds of extras to support informational processes like consciousness - all stuff that is conspicuously absent after death.
Cadavers! So yes, I have mentioned already that a dead body involves the absence of consciousness. You are saying that electromagnetism is also absent from the cadaver? If Consciousness does indeed survive the death of the body, then obviously it does not require the body in order to continue being.
As I have said, such a question (does the individual consciousness survive the death of the body) cannot be answered. Pointing to a dead conscienceless cadaver does not answer that question. It only says that the body has died and that the consciousness which once existed in that body is no longer in that body.
I understand that those who believe the particular interpretations of scientific examination which grants them a feeling of relief have obvious need for such reassurance. I don't pretend to understand exactly what that need is, or why the need exists at all.
We each have needs, and those needs are different for different folk. I can respect those needs to the point where they don't attempt to infringe on my person or insist that I adopt the same beliefs.
In case the physical theory isn't enough to convince, the whole range of human scale interactions has been thoroughly explored experimentally, and the results have borne out the theory to the limits of our ability to measure (which go way beyond scales and energies relevant to human interactions). There is currently no mechanism to support consciousness independent of a living brain. Sorry.
I would say that the truer statement would be "There is currently no mechanism to support consciousness independent of a living brain that we know about."
Which is a whole different story.