The concept of time travel is something that can be hard to grasp as many TV shows have illustrated it in different ways. In Doctor Whoyou can travel through time with a TARDIS. In Back To The Future, you can travel by DeLorean, and in Outlander, you can travel through several geographical landmarks.

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However, the concept of time gets a lot more complicated in Outlander as fans have an increasing number of questions every time someone decides to go through the stones. Who knows, maybe one of the readers might be able to give you the answers you seek, but here are the 10 unanswered questions fans still have about time-travel.

Why Can Only Certain People Travel?

Outlander Claire at The Stones

The most common question fans have about time-travel is why only certain people can pass through the portals. In season 1, Claire was able to travel back to the eighteenth-century after she touched the stones at Craigh na Dun. This was also how Geillis, Brianna, and Roger managed to get back to the past as well.

However, why is it a select few that can do this? Fans know that Jamie can't travel through the stones because he proved so by touching them. We also know that Frank couldn't either so we can only assume that genetics plays a part in it. But what genes have made this possible?

Do All The Time Portals Lead To The Same Time?

Another question fans have wondered is whether all the time portals would lead to the same time. As the viewers know, the stones at Craigh na Dun led to the eighteenth-century, where Jamie was. However, Roger and Geillis revealed they had managed to find more time portals - one in the cave in Jamaica and one in "America."

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Yet, why were they both confident that these portals would have led them back to the present? How come they cannot travel to another period, such as the Victorian age or Tudor England? Do the rituals or gemstones help make the trips easier in some way or another.

Creating A Predestined Paradox?

Outlander Battle of Culloden

In Doctor Who, the Time Lord has said that you can never change a fixed-point in time as it can have dire consequences in the future. However, Claire doesn't seem to care that her actions in the past could end up drastically changing the future if she succeeded in helping the Jacobites win or avoid the Battle of Culloden.

Culloden would be deemed a fixed point in time since they were trying to rebel against the 1701 Act of Settlement, which ensured Great Britain could only be ruled by a Protestant successor. If the Jacobites did win, history as we know it would have been changed and a new present would have been born. Could this mean that Claire may not have married Frank and therefore not passed through the stones?

Jamie's Ghost?

Jamie Apparition

Fans already know that Jamie is unable to pass through the stones as he proved that in "Dragonfly in Amber." However, this has left many fans questioning how Jamie managed to appear outside of Claire's room in "Sassenach." There have been many theories about this ghost, but one idea fans have debated on is how Jamie can astral-travel through his dreams.

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This was subtly hinted in season 4 when Jamie had asked Claire about Brianna's birthmark, which has led people to believe that Jamie had done this sometime after Culloden (ergo the "ghost"). Yet, this doesn't explain how Frank was able to see him since astral projection means you are on a different plane to the human consciousness. So how did he get to the future?

The Concept Of Time

Geillis looking at someone in outlander

The concept of time in Outlander can become quite sketchy when you analyze two characters' stories: Claire's and Geillis's. In season 1, Claire was 27 the first time she traveled from 1945 to 1743. When Claire was 50, she decided to make a second trip back to the eighteenth-century - traveling from 1968 to 1766.

However, the 200-year time span doesn't appear to work for Geillis. In the season 2 finale, fans watched as Geillis traveled through the stones in 1968. Yet, instead of arriving at the same time as Claire (1766), she somehow ended up in 1730, 13 years before Claire first arrived. Are the travelers able to pick and choose the time they would like to go back to?

How Is Time Travel Possible With Gemstones?

Brianna Time Traveling Outlander

In the Outlander series, the concept of time travel is a lot more complicated than having a time machine. To travel in time, a traveler needs to have a gemstone to reach the other side safely (according to the show). However, there is a bit of a continuity error here as the first time Claire traveled through the stones, she had none of these. Even in the books, Claire never used the stones the two times she traveled.

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There is also the rumor that the gemstones can help steer a traveler to the right time. Yet, this can be contradicted again when Claire returns to the twentieth-century. If a stone can steer you into the right time, why didn't she return to the present, several moments after she disappeared?

Is It Possible To Travel To The Post-Future?

One thing all the travelers have in common is that their timeline has proven to be linear. They have only moved from A to B and vice-versa, with all the time portal leading to the eighteenth-century. However, could it be possible for them to travel past their own present?

For instance, could Brianna and Roger be able to travel to the twenty-first century to the year 2020? Where their family would be even safer than the 1970s since medical science has advanced so much since then? There is a rule that you cannot live in a timeline where you already exist so could you just choose a time where you are already dead?

Why Can You Only Travel On Certain Days?

Jamie helping Claire to touch the stones and travel back to her time from Outlander

Not many fans will be aware of this, but the time-portals aren't open every day of the year. They can only be opened and accessed on certain holidays. For instance, when Claire and Brianna first went through the stones, this was on Beltane. The second time Claire went through the stones, it was on Samhain (Halloween).

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Roger, too, was able to go through the stones during the Summer solstice. But can you only travel on these days? Is it because spirits from other dimensions are allowed to roam free on Samhain? Is it because time is transitioning into a different solstice/equinox?

Is Time Travel Safe?

Claire when she first went through the stones in Outlander

Up to now, everyone who has gone through the time portals or stones have made it through safely - which is apparently thanks to the gemstones. However, wouldn't time travel have a detrimental effect on the body? After all, they are jumping 200 years to and from the eighteenth-century in a blink of an eye.

The only way you could explain this is if you travel at the speed of light. However, physicists have even discussed that nothing would be able to travel as fast as this. In fact, this would be impossible for any human as it would ultimately kill them. How is this possible without any consequences to the traveler's health?

Why Was Claire Sent To 1743?

Jamie and Claire together in Outlander

The most obvious question that the fans have about time travel is why Claire was sent to 1743 in the first place. Throughout the five years the show has been on the air, not once has Claire questioned as to why she was sent directly to that time.

Some people believe that Claire had been guided to the time because her mind was thinking about Frank's research, which led to her meeting Captain Jack Randall first. Others believe that Claire was predestined to go back because of her and Jamie's transcendental love. Still, no one has ever given a full reason as to why Claire was sent to this time and not another.

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