Talk:Grandfather paradox

Rephrase

The below paragraph doesn't make sense to me... The first sentence is particularly confusing. Can someone please shed some light on this or consider rephrasing it?

"One variant of the grandfather paradox is that when the traveller kills the grandfather, the act took place in, or resulted in the creation of, a parallel universe where the traveller's counterpart never exists as a result, but his prior existence in the original universe is unaltered.[citation needed] In other variants, the actions of the time traveller have no effect outside of their own personal experience;[citation needed] for example, in the novel The Men Who Murdered Mohammed by Alfred Bester.[citation needed]"

Electricmaster (talk) 11:35, 11 October 2016 (UTC)

Sure. BrightRoundCircle (talk) 23:46, 12 October 2016 (UTC)

Off-topic

I think I have a solution for grandfather paradox. Once you go back in time and kill your grandfather you actually kill him and remove your own existence as well, that is your grandfather will dead and you will not be born, end of the story. So the paradox of "whether you went back in time and killed your grandfather or not, or whether you were born or not" doesn't apply. So there is no argument of " you go back in time and kill your grandfather, thus aren't born, thus you cant go back in time and kill him, thus your grandfather isn't killed, thus you are born so you can go back in time and kill your grandfather and so on", because as I said when you go back in time and kill your grandfather this will be the end for both of you. — Preceding unsigned comment added by Mohammad Zuaiter (talk • contribs) 10:57, 22 September 2017 (UTC)

Please mind that Wikipedia article talk pages are for discussing the article. They are not for general conversation about the article's topic. What's more you merely re-state the paradox, you didn't solve anything. Bright☀ 14:29, 22 September 2017 (UTC)

Is said to

The Wikipedia Manual of Style discourages constructs like "it is said". If the purpose of the phrase, as I was told in the edit summary, is to question whether the grandfather paradox is actually a paradox, then a reference to a reliable source is needed and the information belongs in the philosophy section. I doubt there is such a reliable source, since unlike a lot of other "paradoxes" the grandfather paradox is a true paradox that deals with a self-contradiction, unlike other paradoxes that only deal with apparent self contradictions. Bright☀ 12:14, 7 August 2018 (UTC)

Whether it is a true paradox depends on the Physics you assume. In a block universe a time traveler can only do what history records that he did and there is no paradox. In Branching space-time there is also no paradox. Shmuel (Seymour J.) Metz Username:Chatul (talk) 19:42, 24 August 2018 (UTC)

You use the term "not a true paradox" as if paradoxes are only true if they apply under all conditions, which you'll have to reference if you think that's the correct definition (it's not). Zeno's paradox is a true paradox and it doesn't apply if space or motion is discontinuous. The Twin paradox is not a paradox at all even though it applies in all universes that follow general relativity.

Both the block universe and interacting many worlds are addressed in the article, and it states that the paradox doesn't apply to them. This does not make the paradox "not a true paradox", and if you want to say that it does, you will need a reference saying so. Bright☀ 10:39, 25 August 2018 (UTC)

This is just a paradox, not proved

There is nobody who have undergone something like Grandfather paradox, hence can't be predicted. May become as a theory from paradox, "as future is not carved in stone". Shivanesh77 (talk) 15:20, 24 August 2018 (UTC)

Please discuss the article. Your two short sentences contain several mistakes (for example see history of general relativity for amazing predictions that were made before anybody has "undergone something like them") and they don't directly address any problems with the article. Bright☀ 11:15, 25 August 2018 (UTC)

Baumeler et al (2019)

There's a new article (Baumeler et al, Reversible time travel with freedom of choice, 29 October 2019) which concludes that "consistency with local operations is compatible with non-trivial time travel". Likely worth mentioning it in this article. --Chris Howard (talk) 20:29, 3 November 2019 (UTC)

Tachyons

The article discusses General Relativity but not Special Relativty. However, in Special Relativity with Tachyons the paradox already exists; you can send a message into the past.

Paradox

The thing is, if you go back in time to kill your grandfather, that means you never existed. If you never existed, you can't go back in time and kill you grandfather, so he's still alive. If he's still alive that means you get born. If you're alive you then will kill him, which means he's dead and you're back at the beginning of the cycle. 212.159.102.132 (talk) 11:44, 21 January 2021 (UTC)

"The Man Who Was Never Born"

N.B. Episode of The Outer Limits starring Martin Landau broadcast October 28, 1963. Manannan67 (talk) 21:52, 2 February 2021 (UTC)

it´s called changing the perspective: If you knew in advance, woul dyou ever have allowed your son to be grown. He say´s I´m naster of all allegories. The world is your grandchild — Preceding unsigned comment added by 2001:4DD7:7505:0:6452:739B:B727:BDAC (talk) 21:28, 30 September 2021 (UTC)