9,999 times out of 10,000 (arbitrary number there not meant to be mathematically precise) someone else also had the same idea and has already posted it or published it, probably decades ago.
If you find that they have, don't be discouraged. That shows your intuition is quite good in this topic area, which is nice to know. And sometimes there might be differences between your idea and the published work, which might possibly lead to new ideas and insights, or new ways of presenting it.
I've had this experience myself. I thought I'd invented the idea of "fractal music". I'd never come across it before, and this was back in the 1980s, so long before the days when you can find answers to even the most obscure things in the internet. In the end I wrote a program to explore the idea. This was my first music program and lead to many other things. And because I was following a slightly different path from anyone else in the field of fractal music then it did turn up some interesting music, which lead to my program Tune Smithy becoming moderately popular amongst algo-comp enthusiasts. Also - a feature that I added almost on an afterthought - to add microtonal capabilities to the program - lead to it eventually turning into a useful tool for microtonal composers.
So, you can never know where your first ideas will lead you. But I'd suggest as a starting point, to see if anyone else has published a similar theory, or anyone else is discussing this online. And - I wouldn't worry over much about anyone "stealing your idea". That is unless it is of commercial importance and patentable.
But if it is just an interesting theory, and you are concerned about establishing priority - that you thought of the idea - well nowadays I'd have thought so long as you write about it online in a few different places, and in lots of detail (where appropriate), it's going to be very clear who had the idea, on the (perhaps remote) chance that it is sufficiently original that it is going to be important in the future to find out who thought about it first. Ideally do at least some posts to places that also get archived by the wayback machine Digital Library of Free Books, Movies, Music & Wayback Machine.
Sadly quora posts don't get archived - that's because there is no programatical way to remove pages from the wayback machine. So they have excluded it in their robots.txt - until whatever time some method is developed to do that. That's because they want to assure authors here that if your content is deleted, it is permanently deleted (as best they can anyway), and that if you choose to go anonymous, or change an answer to anonymous, to make it as hard as possible for anyone to trace your identity. Both of those would require the ability to delete pages from the wayback machine programmatically.
There are likely to be many places you can discuss your ideas online, and you'll learn a lot from discussing them with other enthusiasts. So - apart of course from the case where there is some commercial aspect to the idea - that seems the obvious starting point.
If you find a mistake in your theory when you read the published work - well that's par for the course. Even the best thinkers make mistakes.
As for plagiarism - unless you are an expert already in this topic area, then for most people it would be an honour and something you'd be grateful about, if some expert takes up your idea and develops it rigorously, so long as they cite you as the source. But if they don't, you can always point to your posts online.
However do be aware that often many people come up with similar ideas at the same time. So if someone publishes an almost identical result, it doesn't follow that they copied you, unless there are clues that show they must have done so (e.g. using identical notation, in case of mathematics).
There's a famous example in logic. In 1936, Church and Turing published a very similar, ground breaking and spectacular result in logic, in the same year, and with no knowledge at all of each other's work. Turing's work is better known by non mathematicians and is based on his idea of a Turing machine. Church's work was based on the lambda calculus. Later both were shown to be equivalent Entscheidungsproblem
If you find that they have, don't be discouraged. That shows your intuition is quite good in this topic area, which is nice to know. And sometimes there might be differences between your idea and the published work, which might possibly lead to new ideas and insights, or new ways of presenting it.
I've had this experience myself. I thought I'd invented the idea of "fractal music". I'd never come across it before, and this was back in the 1980s, so long before the days when you can find answers to even the most obscure things in the internet. In the end I wrote a program to explore the idea. This was my first music program and lead to many other things. And because I was following a slightly different path from anyone else in the field of fractal music then it did turn up some interesting music, which lead to my program Tune Smithy becoming moderately popular amongst algo-comp enthusiasts. Also - a feature that I added almost on an afterthought - to add microtonal capabilities to the program - lead to it eventually turning into a useful tool for microtonal composers.
So, you can never know where your first ideas will lead you. But I'd suggest as a starting point, to see if anyone else has published a similar theory, or anyone else is discussing this online. And - I wouldn't worry over much about anyone "stealing your idea". That is unless it is of commercial importance and patentable.
ESTABLISHING PRIORITY
But if it is just an interesting theory, and you are concerned about establishing priority - that you thought of the idea - well nowadays I'd have thought so long as you write about it online in a few different places, and in lots of detail (where appropriate), it's going to be very clear who had the idea, on the (perhaps remote) chance that it is sufficiently original that it is going to be important in the future to find out who thought about it first. Ideally do at least some posts to places that also get archived by the wayback machine Digital Library of Free Books, Movies, Music & Wayback Machine.
Sadly quora posts don't get archived - that's because there is no programatical way to remove pages from the wayback machine. So they have excluded it in their robots.txt - until whatever time some method is developed to do that. That's because they want to assure authors here that if your content is deleted, it is permanently deleted (as best they can anyway), and that if you choose to go anonymous, or change an answer to anonymous, to make it as hard as possible for anyone to trace your identity. Both of those would require the ability to delete pages from the wayback machine programmatically.
There are likely to be many places you can discuss your ideas online, and you'll learn a lot from discussing them with other enthusiasts. So - apart of course from the case where there is some commercial aspect to the idea - that seems the obvious starting point.
If you find a mistake in your theory when you read the published work - well that's par for the course. Even the best thinkers make mistakes.
As for plagiarism - unless you are an expert already in this topic area, then for most people it would be an honour and something you'd be grateful about, if some expert takes up your idea and develops it rigorously, so long as they cite you as the source. But if they don't, you can always point to your posts online.
However do be aware that often many people come up with similar ideas at the same time. So if someone publishes an almost identical result, it doesn't follow that they copied you, unless there are clues that show they must have done so (e.g. using identical notation, in case of mathematics).
There's a famous example in logic. In 1936, Church and Turing published a very similar, ground breaking and spectacular result in logic, in the same year, and with no knowledge at all of each other's work. Turing's work is better known by non mathematicians and is based on his idea of a Turing machine. Church's work was based on the lambda calculus. Later both were shown to be equivalent Entscheidungsproblem
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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