Why didn't Zoom killing his time remnant affect his present self?

Timeline Remnant

Speedsters have some immunity to changes in time. As we are told multiple times, only they will remember the changes in time that they make. "It's possible Eobard was in the Speed Force, protecting him like a bomb shelter, keeping him alive and his time line intact. It's what's known as a “timeline remnant”. (Wells-2, Season 2 "Reverse Flash Returns").

When Eddie committed a heroic sacrifice to stop Eobard, we have to note that there was an active singularity open, a literal rip in space AND TIME. The Singularity could have changed things. And to prevent a literal grandfather Paradox (Eddie kills himself, Eobard is never born, giving Eddie no reason to kill himself), time fixes it in the most convenient way possible. By removing the "present" one, which was the oldest. The younger one stayed alive to protect the timeline.

Cisco was also going to be erased out of the timeline, when Barry planned on locking up the younger Eobard in "Reverse Flash Returns", as Cisco was basically created further in Eobard's timeline. We also have to note that Cisco is connected through space and time, like the singularity, to the medium between dimensions.

As for "Jay", we don't know where in Zoom's timeline Jay is from. He can be from the past, OR from the future. Zoom is also crazy, and had no problem talking his Timeline Remnant into dying for this stupid plan.

The show suffers from a complete inconsistent use of time-travel though. It doesn't follow a single theory, so anything can happen as the writers want it to happen.

The Darkness

Yes, it's possible that Zoom somehow created a Negative Speed Force. Just like how in the comics, Barry Allen created the Speed Force (which creates him... ugh, temporal mechanics), and creates more with every step, in The Flash: Rebirth #4 (2009) Professor Zoom (Eobard) eventually creates a Negative Speed Force, that acts like a cancer to the Speed Force. We don't know if the show is taking this theme up yet, stay tune, same Flash time, same Flash channel.

      ?????????????????<???reverses time???<???????????????????????????
      ?                                                               ?
{[A1&A2] @ t=(-1)}??time passes??>{[A1] @ t=0}??time passes??>{[A2] @ t=1}

      ?????>new timeline??>????????>{[A1&A2] @ t=0}?A1 dies?>{[A2] @ t=1}?future?>

This is referencing specifically the latest ep of flash. A1 represents flash accepting the run, and A2 is the flash after he has failed to beat zoom and went back in time. A1 dies because he's from a timeline which ends with becoming A2 to travel back in time making him the time remnant. The part of the timeline that A2 wanted to stop from happening and does by having A1 kill himself.

The flash and any speedster is immune to paradoxes and other things that time tries to create because they are, in essence, the speed force incarnate. The speed force is unswayed by timeline changes. It essentially exists outside of time itself.

Ok.I'm sure that my theory not is correct but this is how I think it is.I've actually got two theory's."

1. Barry goes back in time few seconds before the second one does and convinces him to go to his timeline and they do go.In Season 2 finale we saw time remnant dying and cause of that his whole timeline is gone too,basically like it never happened.

2. Barry goes back in time and the other Barry slows down not deciding to go and make his time remnant.They two stay in his timeline deleting main Flash's timeline(possibly the one we watched on CW). So the main Flash actually becomes time remnant and the story basically continues on Earth 1 version 2 Barry (Flash) followed by the same events in the future as it would happen in the one we watched before.

If you ask me my second theory has got more sense cause you heard Zoom saying "You're almost ready,you just need to be ready to kill yourself.

Actually all this is too complex.Here is short one.

Barry goes back in time for a few second's and dies in process of helping the other Flash.Deleting the main flash (time remnant's timeline).

Hope I explained it good and I know that my explanations are stupid but what can I do.

Timeline Remnant - As it's explained in The Reverse-Flash Returns, Eobard Thawne's Time Remnants are the remains of his own Timeline preserved by the Speed Force playing itself out keeping the current Timeline intact by making sure all the fixed points in the Timeline play themselves out until he's erased from existence in 2015. However due to this Eobard being from the Original (now erased) Timeline where The Flash didn't come into existence until the year 2020 it's most likely the Speed Force sent him back a few years earlier so his Timeline would play out as it should due to the fact he didn't know where he was, and he was surprised to discover that Barry already knew who he was, but in the process he finds out about STAR Labs, Harrison Wells (despite him being the Earth-2 Doppleganger), and the rest of Team Flash. Despite being in an Alternate Timeline, to Eobard the events are playing out as though it was the Original Timeline since Barry shouldn't have his powers for at least another 4 years.

As for Time Remnants that are created in Escape from Earth-2, and The Race of his Life they are created by a Polchinski Paradox. This paradox describes a billiard ball being thrown into a wormhole in such a way that it would emerge in the past and knock its incoming past self away from the wormhole entrance, creating a variant of the Grandfather Paradox.

So as we see in The Race of his Life during the episode both Zoom and Barry decide to travel a few seconds back and just as they're about to open the wormhole their future counterpart appears knocking them off course (like the billiard ball) so they don't travel in the first place. So the time travel never happens (past), and the Time Remnant that's created is now from an aborted Timeline (future) which gives us the variant of the Grandfather Paradox because the remnant shouldn't exist. Though due to the protection of the Speed Force, and that Past and Future are now at the same point in the present, until one of them dies both of them are considered Time Remnants (past meets future, future meets past) which is what causes a problem for the Timeline because when one is killed nothing happens to the other (past never travels back, future comes from aborted Timeline, both at same point in the present). After seeing Barry meet his younger self in Flash Back until recently I didn't see how Zoom could of pulled off the charade of murdering his Time Remnant unless he used the Polchinski Paradox. So basically he goes back a few seconds to create a Time Remnant to keep up the charade of being two different people on 2 different Earths, but since the Time Remnants can act of their own free will the future counterpart then comes up with the idea to make Team Flash believe their friend has been killed by the enemy and convinces the past counterpart to let him kill him to urge Team Flash to get justice for their friends death

The Darkness - Killing his Time Remnant didn't create any Dark Force, the reason his eyes turn black is from tapping into his powers, Barry's turn Yellow, Eobard's turn Red, and Zoom's turn Black. The Darkness he's mentioning comes from the bloodlust he developed after witnessing his mothers murder as a child which lead him to become a serial killer. Due to his psychopathic mind and criminally insane nature Zoom tries to make Barry give into his inner darkness by trying to make him believe they're no different from one another after their experiences as a child, but because Barry never witnessed his mothers murder (and it wasn't by his own father) he never became consumed by bloodlust.

Negative Speed Force - Hunter Zolomon possesses no Negative Speed Force since he had his powers after being exposed to the dark matter except he artificially enhanced it via the Velocity serums. Siphoning the Speed Force grants one access to Speed Force abilities and access to its opposite polarity, the Negative Speed Force which is signified by Red Lightning instead of Yellow. After damaging his connection to the Speed Force, Eobard Thawne was unable to siphon it making his powers unstable until Barry became The Flash in 2014.

The "Time Remnant" could have easily been a different version of his past self. A Time Remnant doesn't have to mean a direct past-self, it could refer to a past-self of a person from a fractured or alternate timeline.

Remnant: A part or quantity that is left after the greater part has been used, removed, or destroyed.

But what IS a Time Remnant? I think a Time Remnant is someone who is from the past, who has more than one future version of them. At some point, their Timeline branches off into an alternate Timeline. So, the future version of them who is in the alternate Timeline (AFTER the point of branching) is unaffected. I think this is how Hunter got away with killing (a version of) his past self.

I'd like to imagine that Hunter somehow got ahold of his Time Remnant from a fractured Timeline on Earth-2, and then manipulated him into doing things, eventually killing him.

Point A --> Point B1 and Point B2 (same person in two alternate time lines)

B2 goes back in time to Point A --> 2 People in Point B1 (B1 and B2A) and 2 People in Point B2 (B2 and B2B) (B1 and B2 are remnants aka leftovers from original timeline and B2A and B2B the new people)

Way I see it, the way time travel works in the Arrowverse is that, as explained in Legends, time takes a bit to solidify. Once it has, alternate timeliness are erased and the new timeline takes hold.

When Barry traveled back in time to prevent Reverse-Flash from killing him as a child, we'very seen as many as four Barry's there at a time. However, when he traveled back in time after Mark Mardon and Vandal Savage (respectively) destroy Central City, he sees his younger self and then replaces it. I would surmise this is because his younger self belongs to the previous timeline which Barry then destroys by changing history, and is erased along with it. However, we've seen that under the right conditions people with the Speed Force can survive this (such as the Reverse-Flash).

I think it's most likely that a Time Remnant is a speedster from a timeline that had been destroyed, except rather than disappearing, this speedster joins the other speedster that created the new, current timeline and there are now effectively two of the same speedster in the same place. For example, the ghostly speedster of the Flash disappears after he escapes the blast from the staff of Horus, but when Zoom is running from the Flash after killing Henry Allen, the duplicate stays, because Zoom had ran back in time to just before that moment and his Time Remnant remained in this timeline.

That's my theory anyway.

From what I understood, paradoxes seem to be relatively harmless in the Arrowverse. What happens exactly, to allow the abuse of time remnants, is that the speedster needs a very strong will and a good knowledge of how short-time travel works.

If a speedsters goes back in time, it changes the pastfor everyone except themselves, which are pretty much unaffected because of some speed force explanation (or, as some might say, deus ex machina).

I'll explain with an example.

Barry is running. Barry knows that he needs to be "two" of himself to beat whatever is to come, and one of those will need to sacrifice himself. The death is probably required even without needing a sacrifice because I would expect more problems to show up if there are two barrys for an extended period of time.

So Barry tells himself. In exactly five seconds, if another me shows up from the future, I'll team up with him and do part A of the plan, and sacrifice myself shortly after. If no other me shows up, then I'll waiut five more seconds, travel back in time 5 seconds, and do Part B of the plan, while letting the past me do the part A and die.

Barry needs incredible resolve to do this, because he has now way to know which Barry he will be (A or B), and once he knows, if he ends up being A, he can't change his mind and has to accept his own death. Only if he gathers that resolve to act differently depending on the time travel, does the time remnant happen. When he time travels by accident, like in Out of Time or Legends of Yesterday, then he simply replaces younger Barry, because that one did not have the resolve to die for the plan, so can't continue to exist.

Everything is decided by the speedster's will to play either halves of the plan even without knowing which half he'll have to play and having to die in one of the cases.

It is actually easier to do for an "evil" speedster like Zoom, because instead of sacrificing himself in plan A, he kills Zoom A in plan B, so he needs a lot less willpower to do that, because Zoom A wouldn't have the option to back off after initiating it, since he will get murdered. Not having that option means he doesn't need as much will to actually go through with dying.

I think what happened was that Barry traveled a short time back in past, asked his past self to go to the exact time needed and then he replaced him. So the timeline remains intact and there are two flashes (One from the past and one who took the place of the past one, therefore, having 2 copies of himself. And about Eobard Thawne, when Eddie Thawne killed himself Eobard Thawne vanished being a paradox but due to multiple time travels done by him, each copy of his past is a remnant. So what should have happened is that one of the copy got to know about the mistake therefore never returned to his original time or the past but also kept moving to escape the time paradox remover(or whoever the hell he is) as shown in Legends of Tomorrow.

Season 2 Eobard Thawne is not a Time Remnant. He is the original one from season 1. Harry thought at first Eobard Thawne is a Time Remnant with his diagram: telling that even if they trapped Reverse-Flash that won't save Nora(won't disrupt the timeline) and he is a Time Remnant because he was inside the Speed Force when Eddie killed himself. But that's wrong because he exists before time traveling in the Speed Force. Yet it did disrupt the timeline.

But after Team Flash's discussion with him, Harry realized that this was always meant to happen. And that he is not a Time Remnant. Hence you have Harry saying this is his origins story.

P.S: There is no original timeline

We still don't know how Thawne still 'lives'. The best answer is that he is a backwards time traveler, thus that's why he wasn't affected. Because even if you were to kill your grandpa for the first time, you have to exist. So Thawne isn't erased because that were his first time jumps. Because he can interact with Team Flash post-Eddie's death that's why people are still puzzled. But you shouldn't be. Because from his perspective, he didn't cause Eddie's death, yet.

So, Thawne lives not because the Speed Force preserves time copies/duplicates inside it, but because he didn't cause Eddie's death, yet. Lol

Barry's mom's death isn't a fixed point. If it were, this would nullify Reverse-Flash's disruption of the timeline when he was imprisoned.

Lastly, the singularity didn't happen due to Eddie's death. It happened because it had to happen. That's why it's the same wormhole generated by Barry that expands wider and became a singularity. If it were due to Eddie's death, another wormhole should have appeared, not the same one Barry generated.

HOPE THAT HELPS!!! ^^