time paradoxes

Time paradoxes are logical contradictions that arise when considering how actions in the past affect the present or future. A common example is the "grandfather paradox," where someone travels back in time and prevents their grandfather from having children, which would mean the traveler was never born. This creates a contradiction—if the traveler never existed, how could they have traveled back? These paradoxes highlight complexities in theories of time, especially in science fiction and physics, questioning whether actions in the past can truly alter the timeline or if multiple timelines or fixed histories exist to resolve these contradictions.