Does Time Reversal Symmetry Apply to All Interactions?

AI Thread Summary
Time reversal symmetry suggests that the behavior of particles should remain consistent when time is reversed. In the case of two electrons, they repel each other, and reversing time would show them moving towards one another. However, the concept of antimatter implies that positrons, which are the antimatter counterparts of electrons, could attract each other if viewed as matter moving backward in time. This raises questions about whether time-reversal symmetry applies universally to all interactions, particularly in the context of charge interactions. The discussion highlights the complexities of time reversal in particle physics and its implications for our understanding of fundamental forces.
FizX
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Ok, so if you have two electrons near one another, they will start to repel one another and separate as time goes on. Now if you reverse time, they will move towards one another. But it is said that antimatter can be viewed as matter going backwards through time. Now if this is true, this would mean that two positrons would attract one another, which contradicts the law that like charges repel. Does the time-reversal not apply to all interactions?
 
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FizX said:
Ok, so if you have two electrons near one another, they will start to repel one another and separate as time goes on. Now if you reverse time, they will move towards one another. But it is said that antimatter can be viewed as matter going backwards through time. Now if this is true, this would mean that two positrons would attract one another, which contradicts the law that like charges repel. Does the time-reversal not apply to all interactions?

Remember that momentum gets reversed as well. Picture the two electrons initially far away and moving toward each other. Then they slow down, stop for an instant, and end up moving away from each other.

Film this, run the film in reverse and you will see exactly the same thing.

Regards,
James Baugh
 
oh yeah! wow i can't believe i forgot about that, thanks alot.
 

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