Not really, just trained as a physicist (molecular spectroscopy).
It's nice to see a colleague-scientist in such a forum

Actually physics and buddhism are in agreement about there not being an independent observer
Let us not mix high philosophy with rough practice. I am an experimenter, and I am sure that direct experience/observation explains things much better than tons of speculations. Especially if we take into account that the "agreement" between Buddhist philosophy and quantum physics is very surface, on the level of very general concepts, while we are talking about specific practical results.
... especially in the context of meditation where it's quite obvious that there is always interaction between observer and what is being observed. Isn't that the whole problem?
Yes, this is the problem. I was talking about an observer (not necessary in meditating state) who observes the meditator, you are talking about the meditator as an observer. These are
different objects. Not surprising that you see the problem where it does not exists.
because dependant or not all signals when being observed come under the influence of observer and thus become dependant.
This is an interesting moment. Yes, you are right, everything what you perceive is the result of interpretation of your energy body. So, formally, we deal only with these interpretations, not with real signals. But, as we often do in physics, we can agree that signals are "real" if their "measurement" has an "error" less than given value. Say, if measurement of weight gives you the value 1g and the error of measurement is less than 1 milligram (or 1 microgram), we can say, that the weight weights exactly 1g, though we know that this is not absolutely true. But, if we would like to know more or less exact number of atoms in this weight, we will have to measure its mass with much greater accuracy (say, to 1 picogram or even better).
The same situation is in meditation.
When you start to work with your consciousness, your "scales" are very rough (i.e. you deal with the coarsest subtle bodies, most close to the physical body). In this case "not clinging" is equivalent to tuning the scales and making them more sensitive. But they still have some error and you know that you cannot distinguish weights in borders of this error. So, how do we check our "scales"? We take more precise scales and, using them, check our "rougher" scales. The same is true with respect to subtle body system.
When you are in the coarse subtle body, you have no means to validate the information obtained using it. To be able to check this information, you have to go to higher body, which deals with energies of higher frequencies. And
then , if you get the same (or similar) information using this higher body, you can say that the information, obtained in the state of being in the coarser body is "more or less" true. But this higher body has its own level of errors, and to validate its results you have to go to even higher body, and so on.
You can say that this process of successive validation will never finish, because each body has its own level of errors, and you will be correct. But if
fix the level (body) whose signals are checked, then we can say that, if these signals are validated from the point of view of 3-4 higher bodies, we can consider the signals of given body being "correct".
So, as you can see, there is not no such thing as "absolute truth", but,
speaking practically, we can talk about "correct" or "incorrect" interpretation and "dependent" and "independent" observers and signals.
Couple of words about "non-clinging".
1) Yes, this is one of the primary "spiritual habits" which one develops on the early stages of his development. But this habit is definitely not the "universal key" which allows you to open all doors.
2) "Not clinging" does not make you free from ego. It does help to destroy
some part of ego, but only just coarse enough part. There are many higher parts of ego, which you will never know about if you stay on the level of "not clinging".
"Not clinging" is like playing gammas for musicians. If you cannot play gammas, you will not become a good musician, but if you
only can play gammas, you are not a musician at all

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