I Observation of the effect of gravity on the motion of antimatter

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The Alpha Experiment at CERN has confirmed that antimatter behaves identically to regular matter under the influence of gravity, supporting the Weak Equivalence Principle. This finding is significant in the context of longstanding rumors suggesting antimatter is "regular matter moving backwards in time." The discussion highlights the importance of experimental evidence in dispelling such misconceptions. The moderator emphasizes the lack of credible references supporting the time-reversal claim and closes the thread for further discussion unless valid sources are provided. The results of this experiment provide a strong basis for understanding the nature of antimatter in relation to gravity.
hyksos
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A test performed on antihydrogen atoms has shown that gravity acts on matter and antimatter in a similar way. The experimental feat is the latest in efforts to probe the crossover between theories of relativity and particle physics.
The Alpha Experiment at CERN has finally produced a paper on whether antimatter falls towards the earth under gravity. The research confirms that antimatter acts identically to regular matter in regards to gravity.

Observation of the effect of gravity on the motion of antimatter. Anderson, E.K., Baker, C.J., Bertsche, W. et al. Nature 621, 716–722 (2023). https://doi.org/10.1038/s41586-023-06527-1
https://www.nature.com/articles/s41586-023-06527-1

The authors of this paper are concerned with a test of the Weak Equivalence Principle, which is great science. My personal interest in this work is a little bit different. A rumor has been circulating since at least the mid 1980s that antimatter can be interpreted as "regular matter moving backwards in time". This rumor was likely perpetuated by a popular book by Richard Feynman. My feeling is that is the results of this experiment should dispell that rumor in an ultimate and finalizing way. Dismissing the rumor via "it was never meant literally" is far weaker than strongly falsifying it experimentally -- which is what we have now.

Your thoughts?
 
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hyksos said:
A rumor has been circulating since at least the mid 1980s that antimatter can be interpreted as "regular matter moving backwards in time".
We don't discuss "rumors" here. I am not aware of any valid reference (textbook or peer-reviewed paper) that makes this claim. (Even Feynman in the popular book you reference did not make it as a claim about "reality"; he only put it forward as a mathematical trick to help with calculations.) Therefore, without any valid basis for discussion, I am closing this thread. If you can find a valid reference that makes the claim, PM me and we can reopen the thread to discuss it.
 
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Thread 'Is using r as a coordinate in Birkhoff's theorem a limitation?'

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