is it possible to create antigravity conditions on earth?if so,how?
The term "antigravity" is not a scientific term and can apply to any number of things. Does it apply to a helicopter or rocket by your definition?
Note, the way the word is typically used is by crackpots who are arguing against the current theory of gravity (saying they can shield or cancel gravity as opposed to just acting against it) and if that is the usage you are asking about, then no, it is just crackpottery. Also note that we don't discuss crackpottery here, so this is as far as such a discussion can go.
the graviton is it's own anti-particle , so no
The answer is we don't know what gravity is. I suspect that when we really discover what gravity is, we may discover a new phenomenon of antigravity.
PS - dear moderator, pls to not label someone a crackpot who disagrees with your theories. When you can discover something for a fact, it is no longer a theory. Hence, most of what you tout is still theory, until you prove it, don't call someone who challenges it a crackpot.
I believe it is our duty to question everything until it is proven.
They aren't "my theories". You need to learn what science is/what a theory is, because saying something is a theory is a much stronger statement than you think it is and challenging a wildly successul theory in such a way most certainly is crackpottery.
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