Not necessarily, if there is a barrier you can't cross. Like say it's made possible in the year 2100 and in later years you can always jump back to this starting point but not anywhere earlier for some reason. It might work like a reset point or a time loop but you wouldn't be able to travel all the way back to the big bang.
@@viestihuuhaa7092 watch out for Ted Bundy. Stay out of Washington, Utah, Idaho and Colorado until 1976 and don’t be anywhere near Florida in January of 1978. Then go watch his trial.
The ability to travel through time, whether it is to fix a mistake in the past or gain insight into the future, has long been embraced by science fiction and debated by theoretical physicists. While the debate continues over whether travelling into the past is possible, physicists have determined that travelling to the future most certainly is. And you don’t need a wormhole or a DeLorean to do it.
One of the reason i actually love infographics is how they connect their animation with their storyline to help you understand what they are talking about. Kudos.
Something that people don't talk about much is that time machines would have to be able to travel through space as well. Earth is always moving and it would be incredibly hard to be able to know where it would be at the time you are traveling to. Even if people could time travel back in time, they would have to solve this or they would just die in space.
Probably more things to consider. One big problem I see in time travel, if it works, is where you could end up. The solar system is propelling as we speak and so if someone today traveled into the past, they might find themselves in space as your current location is somewhere the earth hasn't reached yet. Same principle when going to the future but this time you'll be somewhere that the earth had already left.
Problem is past and future does not exist, only present. You can understand time as exposure, similar to sunlight which can make you sunburn, while time - age. Lets say time flows slower for you because you move fast like in this video- time exposure is working slower on you, and faster on others. Fast speed is like sun cream in sunlight exposure example, you get less exposure effect.
Black holes are the only plausible way to potentially time travel to the past. Because of the nature of a black hole's gravity space and time are merged into one combined dimension. Therefore every moment of time from the black hole's formation to its ending exists within that singularity. If it were possible to safely enter the black hole and navigate an appropriate trajectory within it, one could theoretically emerge from that black hole at any point in space and time along the black hole's path.
@@T2jefe No, I've done it just now and as a test, I killed my grandfather. I guess it didn't affect me because I'm still texting this mess....................... [user no longer exists]
My question is this: if time is simply a concept created by man and doesn't actually exist, would it even be possible to create an "artificial" time machine or would these "natural" ones be our only possibility at a solution?
Time is not something conjured by mankind. Perhaps we have a rudimentary, arcane way of describing it, but time is apparent throughout nature and the universe. You're basically asking if since water might be a figment of your imagination, is it therefore possible to build a boat
@@datboy038 Also, the opposite would have to be true, right? If everything is made up by mankind, anything should be possible because reality is based on your perception
If time has meaning all the way until the universe dies and nothing happens anymore, then thousands of years is definitely less than 0.0000000000000001% of time itselt So I don't think we'll ever really understand time tbh. We can barely even wrap our heads around the idea of how small/large something can be
Theirs a difference between manipulating your perception of time, and traveling Outside of it. The term ‘Time Travel’ is typically used to generalize the idea of altering one’s position in the greater flow of time. However the understanding of time travel is essentially the necessity to leave the flow of time in order to forcibly re-enter the flow at an alternate point. The phenomenon this video is explaining is Not Time Travle, but Time Dilatation.
@@KindOldRaven not quite. ‘Time Dilation’ no matter how extreme cannot reverse the flow of time. It can only alter the rate at which you Experience Time, rather by speeding it up to experience a single second for hours, or slowing it down to let millennia pass in second. While actual ‘Time Travel’ would allow you to travel backwards down the time stream and simply re-entering at an earlier point.
Even if you could slow yourself down enough to to travel reverse down the time stream, the energy necessary to do so would be so extreme that exuding it would likely cause a Break in the time stream, causing massively catastrophic… something, something really bad. Inconceivably bad. And I don’t mean cheesy ‘the end is nigh’ horror movie bad. I mean for real chained up in some psychopath’s basement and being forced to watch as they torture your loved ones to death in front of you, kinda bad.
Yes time dilation is not time travel for the future for you, but for observers yes. Theoretically, you go so fast that space moves against you, so time runs out for you differently than for people on earth. If you went 99.9999% of the speed of light and made your way to Proxima Centauri and back, it would take you about 6 years for the people on the Earth about 8492 years so if you returned to the ground you would be on completely another planet :) .
If travelling back in time could end the universe, then surely it would have already. The fact we are living right now means travelling to the past will never be possible.
You're ignoring all other possibilities. What if predestination paradox is real? What about the multiverse, alternate timeline? What if events of time travel to the past are already destined to happen?
I want to go back in time to the 1960s, seeing Muhummad Ali in his prime, the Civil rights movement, him knocking out sonny liston and his fights rumble in the jungle, and the thrilla in Manila in 1974 and 1975.
@@miraperko7493 you're lucky! I know that sounds weird but I was born in 1998, 5th of September. I wish I was born in the 1940's to live in the eras of : the 60's, 70's and of course the 80's. Classic cars, classic music and classic films, Muhammad Ali, Sylvester Stallone, Arnold and Van Damme in their prime.. What a time to be alive
Time travel technically doesn't exist because its only relative to us and our distance between each other so it's basically a fragment of our imagination, a way for us to understand to a point how it works.
@@배진아-d1b exactly. Time is just change. If nothing moved, there would be no time. Does water clock really measure time or just how much water is moving. If I change the date on my phone, have I moved back in time or just changed the dates?
@@배진아-d1b That’s as silly as saying distance or weight is man made. Time is measurable, but relative. Distance is measurable and not relative. Weight is also measurable, but relative. Distance, weight, and time are all easily observable.
@E Van you would be the same age, for you time would pass normally. But as the example in the video states if you traveled 99% the speed of light for 12 hours then turned around and came back at 99% the speed of light, 24 hours would have passed for you but 192 years would have passed here on earth.
It's obvious that physically traveling to the past is and will always be impossible. The actual past only occurs once at a specific moment in time. Once it happens, it's done and gone forever. Just because information (in the form of light) from that moment can exist beyond the event doesn't mean we can interact with it. That would be like trying to stop Adolph from invading Poland by yelling at his image in old documentary footage. You can do what you like to the film footage, but it won't change a dang thing in the past.
We’re all traveling forward in time. It would be really weird if we weren’t! But I found a way to jump forward in time by many hours in just minutes. Every night, I jump forward ahead about 8 hours to the morning, just by closing my eyes for a few minutes. When I reopen them, it is morning! Some people have mastered how to do this by years, not hours. If you ever want a glance at your past self, take a look in the mirror: light takes time to travel from your body, reflect off the mirror and back to your eyes - so by the time you see your reflection, you’re looking at a past version of yourself, not the present. Or if you really want to see how you were in the past, find an old youtube video you watched and commented on 8 years ago!
This is absolutely one of the best channels on YT, no doubt! Their whole team is pretty amazing being able to put together 2 videos a day. Much respect and love for the infographics show!
That's why I'll go even more back so that i can see if the mythical creatures were real Or not id like to see Leviathan and other biblical creatures, including the extinct ones like Titanoboa, Ichthyosaurs, T- Rex, Megalodon etc. These are the era where you only have to fear the animals
So wait, if an astronaut travelling at 99% the speed of light travels 190 years into the future in just a second, what would that look like for the rest of the universe? A spaceship travelling from A to B over 190 years? But for the astronaut it would feel like just 1 second? Or would he have to wait in his ship 190 years, but just age by 1 second? What would that look like for us on Earth if we could see him via a livefeed?
24hrs is 192 years, so if the ship left on Feb. 27th 2022 the astronaut and the spaceship would be 1 day older and to them it would feel like it was Feb 28th 2022, but the year on Earth would be approximately Feb. 28th 2214
The astro would perceive 1 second has passed while the world around him/her ages 190 years. An observer would notice the astronaut zoom away and not come back
"thank you for uploading these videos. Even if I'm having a hard night, I just put a relaxing astronomy video on and listen. It always makes my nights go much easier. Thank you!!!"
I postulate that two distinct types of time travel (TT) could exist. Type A being what is typically depicted in science fiction, where one travels within one quantum reality or timeline. Changes made would ripple in both directions. You could describe this type of TT as destructive. Type B TT is based on the notion that it's impossible to change events in a quantum reality that have already occurred. When one travels back in time and makes "changes", the quantum reality splits. You end up with the original timeline and a new timeline that reflects the changes made at the incursion point. Changes ripple both ways as this is a new timeline, all other previous changes get recalculated and even more new timelines get created. The equation to this would be QRs = 2^(n-1) +1 with n being the total temporal incursions.
One more possibility is there and that's in whatever way or how many times you try to meddle with time there won't be any change cos time is inevitable and the present which you want to change is the time which resulted with your meddling and the future can't be changed as well . As dumb as it sounds it's my theory anyway
According to your second theory you wouldn’t be making a new timeline, but simply joining alternate timeline where things went differently. Even hypothetically it can still run into issues though. By the time the quantum realities split, the people on the other timelines would have become different individuals, and it is unclear whether someone can just abandon themselves in their original timeline to replace someone else in another one, hypothetically.
Alright let me try and explain this a bit better. So far going back in to time is impossible but possible. Why I say this is because of the following: 1.going back into time creates a new timeline making it like it never was your timeline you created a new future with a different outcome that made you not being able to go back into time. Remember everything has a domino effect. 2. Going back in time in which universe (multiverse) as mentioned before it either effects you or it effects a different you which is almost impossible to know. 3. Pushing you back in time has many issues and depend on how it effects your surroundings let me explain in options. Option a: you aren't going back in time but the universe. As you yourself continues in normal time while the universe around you goes back in time requires immense power, as strong as being able to effect the universe itself besides those whom can create time distortions. Which is absolutely impossible with what we got and what type of civilization we are. Option B: you in person going back in time. Now you can't just say I'll go back to April first 1968. You aren't the master of time you are only using it. Your years and days do not work with the universe, it only works with planet earth due to the solar system. Location is also uncertain as you are commanding your atoms and molecules to not only go back in time but to actually jump into that timeline (teleportation) which requires you to be torn apart and put back together without any issue. To say at least that the device won't effect the surroundings after your action that is. You have to command your whole being to go into a specific location in Xas Yas and Zas within the universe. Which also takes lots of time and energy also ignoring what it effects if you stay there permanent or temporary. I am also only scratching the surface right here....
Because maybe there’s a rule in the future taht any time traveler must keep his secret that he’s not from that time line if not like the video said it can create a paradox
It's insane that the Earth Tech internetional actually tried to recreate wormholes based on the theory of the relativity from Einstein, and they actually where successful.
This might be considered sci-fi, but I like to imagine that if subside tried to mess with the past, time would defend itself in some firm or fashion, so that it can't be tampered with.
@@krishpatel7749 1 of my favorite Sci-fi shows presents the idea that what we look at as extraterrestrials are just humans from the far future. UFO's are just vehicles from the far future and that they only time travel back in time to study human history. If what the original comment said were true then it would explain why they never interact and why they flee as soon as they are spotted. I know this also my be Sci-fi but it's fun to imagine.
There's another major problem with time travel I made but people ignore it: *you simply can't time travel further than you were born and died, because you didn't exist prior to your birth and won't exist after you die.* Hypothetically even if you could somehow over overcome this problem the timeline would assimilate you into the time period you travelled to, which is unlikely
If time travel was possible, that wouldn't be relevant because everything that had ceased to exist at the point from which you travelled would potentially have to exist again at the moment in time in which you arrive.
Not really how it works, I know it's crazy, but especially with going forward in time, you don't die, you almost disappear, life on earth goes on slowly, but flying through space high above are you, who's ageing normally, if you leave earth at 25, you could return at 26 with the same body, but 200 years have passed, you then simply carry on living for 60 years on earth as your body ages normally. Unless they manage they build a time loop, I don't think we'll ever go back in time, it would mess it up so easily. Just stepping on a leaf could alter the whole world we live in. But going forward without coming back is certainly possible, it's what we already do.
There's a more basic issue to solve before taking the leap.. destination coordinates. Planets, solar systems, etc. are all in motion. Thus, if you want to travel to a different time on Earth, you'll need exact GPS coordinates for past/future Earth at its position in space relative to your current position. LOTS of moving objects with gravity to factor in, and the 'further' you travel in time, the greater the physical distance and gravitational pull of distant objects. Then, to return home, you'll need to follow that same 'time lane(?)' back. Assuming you're returning to your origin, otherwise new calculations will be needed. So time travel _also_ has a less obscure aspect in that you really are traversing great distances through real space, albeit through a spacetime shortcut. But hey.. if you've got your time machine working, I assume you can handle intergalactic trajectory calculations, etc. ... until support builds for some theory - that nobody can prove - about anomalies self-correcting everything above. TLDR: ¯\_(ツ)_/¯
I kinda hypothesize that if anything in the past gets altered, it’d automatically create an alternate reality, and sometimes gets overlapped with our known reality. Meaning that in some cases, if you talk about some things though the idea that two earth reality’s are working simultaneously, many “conspiracy’s” might no longer actually be a conspiracy. For instance, if you looked at ghosts with this idea in mind, you could look at them as being people who have in fact died, but shouldn’t of, and only died because of the altered past, meaning that they are now technically trapped between life and death and/or are cursed to live in a constant loop. I know a few other ideas, but I’m sure that their might be other examples that you guys could conjure up using this knowledge. This is all still theory, but I’ve been looking into this for many many years and if you consider the “UFO” study’s of the 1940s and the black hole study’s, and then eventual creation in the 21st century I’d say we are closer than people think. Einstein and Steven hawking both theorized that time travel might become a thing if we improved our study’s into black holes, which we are in fact doing now….I just assume that, if the government, or any private organizations did manage to create time travel, I dont think they’d unveil it to us, and may even use it to follow through with their private agenda.
i didnt read all of that but it would make sense that either nothing would happen in our universe and or a new timeline would be created and maybe even destroyed when you return (if you return) so causality isnt broken.
@@sankaranarayanan831 as of right now no, but worm holes might show to be a different story. Worm holes and black holes are similar, so studying into one and understanding one, could help you understand the other more
This is a cool video, but I do want to explain what it would actually take to time travel traditionally. First of all, yes it’s possible to time travel traditionally but there is no way with our limitations we could do it before the sun explodes. In order to time travel you would first need to move faster than the speed of light and break through something called the “light cone” into the fourth dimension (the fourth dimension is time) and then once in the fourth dimension you would be able to walk through time like you walk through a park, BUT the problem with this is that with our current limitations it’s impossible to go faster than the speed of light because of a physics law that simply put states that the more you approach the speed of light the more your mass increases and once you reach the speed of light your mass becomes infinite and since mass is weight we don’t have anything that can push through that yet, and that’s assuming we ever will.
i used to think about time travel/rewriting history A LOT like allllll the time but then one day the idea was proposed to me that time travel is real and already exists but those who govern the time stream deemed all of our history as we know it absolutely necessary and this reality is the amalgamation of time travelers already having worked their magic to correct history and this just happens to be the best version we can get. anyway i don’t think about time travel anymore
Given that when you look deep into space you are viewing the past. If we take this concept and say theoretically, we have figured out how to make warp drives. If one was to warp away from the earth at 1% faster than the speed of light and travel far enough away, if that shuttle were to immediately warp back going 2% faster than the speed of light, you would theoretically arrive back to earth before you left.
The bad logic that keeps getting propagated is that the light that bounced off matter isn't the matter itself that the light had bounced off of. You would just arrive in time to still see the light that had bounced off of you as you were leaving.
Thats from our perspective, for the photon itself travelling at light speed time stops. From photon view it's instantaneous. Thats why speed of light is an unbreakable barrier. Only gravity can help us control light and time. That too at supermassive black level.
Going to the future happens to some people everyday. A patient slips into a coma and wakes years later. To them they have jumped into the future. Some have awoken to a world they never knew…
You cant travel back in time its imposible. I will give you whatever supernatyral abilty and you still cant travel to the past. For me to travel to the past you need to move everything that exist back in time every particle every energy every earth rotation every atom everithink that exist back in time thats imposible.
What if travelling to past means entering a new universe where your appearance will change future events experienced in previous universe? There's the multiverse theory so I thought it would be cool if by time travelling to past we actually travel to different place with different version of ewents. Also, the quantum physics say that a matter can appear in two places at the same time.
It’s the idea of going faster than the speed of light is impossible for a human. In theory you are correct but we will never figure out how to make a human go that fast without harming them in anyway
The reality is just that light is not matter. There is the actual matter of the object (spaceship, time machine, human, etc.) and the light that bounced off of it, that is collected by someone's eyes/a camera. If you could travel in a circle faster than light, you would just be seeing the light that had bounced off of you as you started moving.
Stick with me here. We live in a 3 dimensional world. Time is considered to some to be a fourth dimension. We can move about the first 3 dimensions freely but in time we move only forward. If a Time Machine were created and someone were to travel back in time or into the distant future, would they move only in time or in space too? In other words, In movies someone travels 50 years back and they find themselves in The same spot just 50 years prior. Well wouldn’t it make more sense that they are only moving in time and they would travel 50 years but in space, earth wouldn’t be at the same spot. Does that make sense? So they would reappear not on earth 50 years prior but that one specific location where the Time Machine was at the moment of “travel”.
What I think is: We know that the farther we go light takes more time to reach us. Its also a fact that a lot of stars we see in the night sky are already dead but still we can see them because of thier light. So literally we are look at the past, seeing something that isn't there/used to be there. But this is somewhat but not exactly timetravelling as i somewhat found a flaw in it i.e, we can see it from far away but the more near we are the less paster(you get what i mean) we see. But there is way to overcome this if we want to see something from much nearer and we have it, Telescopes. There may be many other flaws but i havent figured them out yet. Edit: I think we gotta go faster than light to see EARTH's past not those star's past coz the light reflected from earth in the past would have reached far away and to catch up to something from behind, you gotta be faster. A somewhat flaw but not exactly a flaw
Although by 70, he probably already had fathered his children. It still might present a paradox though, since it might impact what decisions his children will make after his passing.
If you travelled through time in a time machine on earth, you'd end up in empty space because the solar system would be hundreds of thousands of miles away by then since it's constantly moving.
To travel back in time would be a fascinating thing to do, but of course, could also be a dangerous thing too, not that we'd find out anyway cos self-repairing paradoxes and all... :P
We do have the technology to time travel into the future. You just explained it. And, we have proved it as you explained. Yet you started with dissent. Only the travel to the past is still hypothetical.
Look i'm no scientist but i think if you would travel back in time, you would end up in some sort of a parallel universe (if they exist that is) thus anything you do there don't actually change anything on your own timeline universe from which you initially travelled from. That's a way to fix some of the paradoxes i think. I don't know.
I agree. There would be no grandfather paradox because if you killed your grandfather back in time it would make your birth impossible only in that time. In your original timeline, from where you time traveled, your grandfather was or is already alive therefore youve been born
Imagine the timeline like a strong river. It only keeps flowing forward. So you can use it to swim down stream with it (Traveling into the future) but once your already in a further spot you cant go backwards to the "present". Now there is some what of a way to travel back in time, you cant cut straight though the river up stream, but if you held on to a rock in the river you could "pause your self" letting time flow past you. For example you opened a time portal. You could only go back as far as the portal has been opened.
Good analogy until you added the rock. You can only think of time as a river, it isn't actually a river. There is no "letting time flow past you", you still have your personal existence as part of everything moving forward in time. And if there was a way to travel through time, cutting "straight through the river up stream" is entirely desired from a time machine. It would be like exiting the river onto the bank, walking along and re-entering the "river" up stream from where exited.
@@Vaeldarg yeah, what i meant was one scientist while we were still experimenting with particle accelerators, was able to freeze a particle for a millisecond. Now we still are far from the technology for necessary time travel to the past but thats another example but i used the time portal for the more logical explanation.
3:44 you mean the ultra wormholes from Pokemon sun and moon like the ultra Necrozma boss battle when you travel through light-years to reach megalopolis in
Here is what EVERY sci fi show that depicted time travel ALWAYS leaves out...displacement! That is, if I had a time machine and wanted to visit myself in my house a year ago...my house is not physically located in the same place in the universe after a year. My machine would not only have to be capable of moving me through time, but it would have to accurately move me thru space to the precise spot where my house was a year ago. If you guys ever saw a sci fi show that took this into account, please let me know.
@@Im_STRAIGHT_up_GAY I know. Although does the same thing happen within the galaxy, as it does inside a moving train or airplane? An example used inside a moving train, involved tossing a ball while the train is in motion.
My thoughts if time travel is in fact possible. First thing you do is find the date in time you traveled to. There's also a major concern when talking about traveling through time: alternate realities. Moments pass every second that you're alive and with that said, you would only be able to travel forward in time, never backwards. Even if you "thought" you had traveled to the past it would be a distorted version of said past, meaning it would actually be some other future. Example: It could possibly indicate that you're in a completely different timeline where civilization didn't advance as fast or as far, hence another reality. Once you travel to any point in time, you have already disrupted/changed the world around you the moment you arrive. Your mind would run wild and play tricks on you.
@@ValdemarDeMatos I tend to stray away from using the word "universes" as a plural, but you're welcome to if that helps you understand better. When I think of the word universe, I think of one singular universe only. Because when you say "universes" it's almost implying that you can travel to and from them. If you were to travel through time it would be the same universe, but only YOU would have the knowledge of your own world and there's no going back. Same universe, just a vastly different consciousness among all other beings. Even if you time travel 10 seconds into the future or 100 years, you're still bending space and time.
Dude, this video is based on facts. Maybe you are right in some ways, but definietly if someone who is studying physics for example for 30 years, it is impossible that you would know more about time travel than the person does. Just look at it the way that you are learning about it, because there is 99.9% chance that have no clue what are you talking about.
It depends on how the machine will work. In reality, one is traveling in the present, if one travels near the speed of light, and returns at a later date.
I would go back in time and prevent and undo man’s mistakes like canceling 101 Dalmatian Street, Season 4 of Yu-Gi-Oh GX, final season of 5D’s, and rewrite Dragon Ball, oh and undo Yu-Gi-Oh! Sevens and make season 3 of Vrains longer not 17 episodes
Ain't it sad that eventually if humanity does figure out time travel it'll be only accessible to the rich and powerful? Think about it it'll cost an exorbitant amount and what they'll just trust a random nobody with time travel?
Travel backwards through time is impossible. We do travel into the future, but cannot jump to some arbitrary future time. 3 reasons time travel into past is impossible. 1. We are constantly moving through space as we move through time. Planet rotates, revolves about sun, solar system revolves about galaxy. To go back in time means to go back to the space at that time, utterly impossible. 2. Travel into the past means that BOTH past and future exist simultaneously. This implies that every past event and every future event have ALREADY happened, this is not the existence we perceive . 3. Time does not exist as a fundamental thing. Time and space are both emergent properties of a more fundamental reality. Causality is more fundamental that time. To go backwards in time requires effect to come before cause, the universe would be broken , so time travel into the past is impossible.
The #1 issue to all time travel, how do you anchor the time travel technology to earth. If you travel to the past the earth let alone the entire solar system, galaxy, and the universe itself would be in a different location. Unless you can create some kind of quantum anchor that is consistent throughout all of earth's history, if you travel back in time you have no way to get to earth in a reasonable amount of time.
I love how this show covers and explains just about anything but when it comes to describing space and time "this is just how the universe works" at 1:07 😂😂. I genuinely spontaneously giggled and thats saying something
Where can i report what i see on the skys @ night? Almost everyday i see flying UFO look alike i am not sure which is which... last week i saw a time traveling UFO in person... but it's hard for people to believe me @ home...
I watched a SciFy short movie where Time travel in the Future was possible. People would Book their vacation back in time to Watch catastrophic Earth events such as Mt Vesuvius Volcano explosion, Titanic sinking etc. Pretty Good Concept!
Or you could just reverse the flow of everything. Would take a wicked amount of power, and if Adams are missing, then when everything's going backwards, a different past will play out. Not technically time travel, just the reversal of everything turning the past into the future.
Regardless of the amount of power, how would it be applied to reverse entropy of even a small area? Also, time still moves forward even when matter moves backward. (walking backward, driving backward, etc. still spends an amount of seconds forward in time to do)
In my opinion, time travel is impossible, neither in the past nor in the future because energy, mass, is not stored in the universe like an audio recording on media format. Past or future events are only stored in our minds as events. If we reach the speed of light we just stop our time, but let's say we want to go back in time, we will have to rebuild all the mass energy in exactly the same shape as it was at time x. And that would mean that even those of us who want to go back in time will be the missing piece in this energy puzzle.
Aren't we also going really fast relative to the sun? So technically does a person living on earth experience time differently then someone who lives on another planet orbiting a star at different speed?
Depends what you mean by experiencing time. Everything is moving forward through time, it's just not everything is experiencing that time the same way. If you take a snapshot of the entire universe, you can see that while it might be dark outside, the sky could be starting to lighten on the other side of Earth. All we use the Sun for is as a reference (amount of light, where the Sun was positioned in the sky, etc.) for when something happens as everything universally moves forward in time. Someone on another planet orbiting another star would just be using that as the reference for their calendar rather than our Sun.
If you were run back and forth from a point A to point B instead of walking from point A to point B If it were the same scenario If you ran up you would encounter an event that would become the past if you were to walk to that same location Running back from point B to A you would reach a point and observe the minor changes in the surroundings that you would get to witness if you walked from point B to A
You're tethered to the timeframe you are in, you can accelerate through it, but as time itself doesn't flow backwards, you can't go in reverse. The only way you're going to get time travel is by moving outside the dimension of time. When you do that, you are no longer are an object in time, at that point you can move to an earlier time, and tether / re-enter time at that point. It doesn't cause a paradox, because an object that is outside of time doesn't exist in time, and when you enter back into the dimension of time, you're a new object, you're not tethered to the original timeline. Now if someone else time travels, they can mess with your time, because you're an object in the time frame when they changed time. It gets weird at that point to explain. On a philosophical you can say you destroy the current timeline, and it changes based on what you changed by entering time at that point, killing everyone who "existed before" or they never existed, or if you believe in fate you can say that was always what was going to happen to them and whatever else but. Anyway, TL;DR Doesn't create paradox. Is possible. Doesn't end the universe. Object that moves out of time gets a different quantum signature. When re-enters time that signature doesn't match / isn't tethered to the previous timeline, and gets a quantum signature that matches the current time flow, so changes in time from that point forward are not attached to the persons quantum signature anymore, so nothing happens.
