I recommend the light touch theory. Such as over powering household electric wiring causing a minor fire to claim insurance money. As for the fixed points in time, are in my eyes examples are Albert Einstein father of relatively, or his famous letter to Roosevelt. Hitlers fourth Reich. Post media television POTUS Ronald Reagan, time selected him as President cause he had to perform good on Television to keep maintain world order and a smooth transition to a post cold war millennium. These are fixed points in time. Hypothetically speaking the unraveling of the ball of yarn results?,, I foresee two possibilities,, it will all work out in time😉 or its the sound of smalls stones effect,, hence causing a unstoppable avalanches in the mountains resulting in a avalanches everywhere else. Each collapse of fixed points, creates a space time fracturing paradox. The results of which could cause a chain reaction that would unravel the very fabric of the space time continuum, and destroy the entire universe!!!! Granted, that's a worse case scenario🧐. The destruction might in fact be very localized, limited to merely our own galaxy.
Solution to causal and bootstrap loops: An original you in a future timeline created the message or object to bring back along with the information to your past self of the exact instructions of what to do to sent it back in time along with the same instructions to go with it. This creates an origin point that will continue to loop.
The answer to the bootstrap paradox is that the lucky charms will keep cycling around until they expire and its no longer something you wanna give to your past self. Then you just have a regular beaching time line-style paradox.
The Grenfell Tower fire could be a good example of this. The event was tragic, and lives were needlessly lost. However, some good will come of it eventually. Not least of all, updates and better enforcement of existing laws and regulations will make builders think twice before using inferior cladding to save a few bucks, as well as incentivizing them to think in longer terms or risk fines/imprisonment/etc... BUT! If someone went back in time(say, for example, the child of one of the victims) and stops the fire from happening to save their parent, it could cause all sorts of issues. Especially ones involving future buildings with similar cladding, thus exacerbating the already existing issue.
Douglas Adams wrote one line in one of his "The Hitch Hikers Guide to the Galaxy" books that ruined time travel as drama for me. In THHGTTG universe time travel exist and is as common as airline travel. The Guide makes this one observation about time travel, "Time travel by its very nature is discovered at all points in history simultaneously". Despite THHGTTG being written as comedy science fiction the logic of the line is undeniable. Time travel has the same effect on the differences in time as airline travel has on differences of cultures around the world. As our world "grows smaller" due to ability to travel from one point on the globe to another point, different locations start to look more and more the same. Time travel would have the same effect on different times except the change would be instantaneous. No matter what epoch you travel to there will be a Walmart. In THHGTTG, there is a restaurant at the end of the universe where you can have a good meal and watch the universe collapse in on itself. At the other end of time there is the "Big Bang Burger Bar" where you can watch the universe be born while having a burger and fries (chips). For that reason time travel as drama is dead to me. I cannot get invested emotionally. Time travel only works for me now as comedy and parody. Thank you Douglas Adams (typed in sarcasm).
Sounds a bit stupid to never take a concept seriously because one person made a weird joke about it. It'd be like if I said I could never take any sort of medieval fantasy story seriously because of Monty Python and the Holy Grail. Besides, that time travel stuff makes no sense at all IMO.
One way to address the bridge hypothetical might be to find a time before it collapsed where it was empty for long enough to get a few heavy enough vehicles across (with secret self driving technology form the future, which seems like you could bring with you?), to collapse the bridge on purpose. Not sure how you would disguise the fact no one died tho.. Maybe if you could find or create a point like this where it was unstable enough for just one really heavy truck to do it, you could fake your own life, and then death to make it seem like you were the casualty.
A chronal diving bell. However after you step out of the bubble, back in the new present. You become a part of the stream again. Time takes change like a stone dropped in a moving river.
Bridge solution- go back to when the bridge was finished, but before it opened and trigger what cause the failure that prompted the changes to bridge construction.
The bridge problem is quite simple. Secretly cause the bridge to fail at the pre-existing failure points, during a time when it has no people on it. Such as standard maintenance. This could be achieved by convincing the powers that be, that a full closure for a single full upkeep would be cheaper, and cause the least overall disruption to the people typically using said bridge. the bridge then fails when no persons are at the failure point, as it was setup to fail at the same points as it would have anyway, the flaw is still found, changes still made, innovations still occur, but loss of life is removed. This hypothetical answer however, steps into the realms you touched on, those being, how much resources does one commit to such a historical alteration, who decides such an alteration is better then how history unfolded naturally, and what potential ramifications could still come from this act? (perhaps one of the people killed, now surviving, is somehow directly, or indirectly, responsible for an even greater catastrophe?)
I love the range of things you watch and cover! I do think Star Wars time travel is somewhat fluid though as Asoka was dead until she was pulled through time. Of course I've barely started the video so perhaps you address things, you're fairly thorough. If you're ever in Oakland California I'd love to pick your brain a bit!
Set things up so that the bridge does collapse, but with no one or as few people as possible on it. The floor is still discovered, the new regulations are introduced, but there’s less loss of life.
What side series of doctor who would you love to see happen like Sarah Jane Adventures? I can't think of any myself. Maybe a side series with Bradley Walsh.
All of this operates under the assumptuon that physical travel is possible. It could be learned that time is not something that can support travel at all, with the single exception of simple observation (think of the historical accuracy that could be acheived).
I have one motto for time travel, "DON'T **** WITH THE TIMELINE UNLESS YOU WANT CHAOS EVERLASTING" cause in my mind nothing good can ever truly come from it in the end.
Professor Farnsworth said it best: "Don't do anything that changes history. Unless you are supposed to do it, in which case for the love of God don't NOT do it. "
my problem with time travel is it breaks that matter cannot be created or destroyed. Every atom in you body is replaced every 10 years or so. So everything in your body existed in some form or another 10 years ago. So if you go back in time 10 years not only have you destroyed your matter in the present you now have duplicate matter in the past.
People always over think this shit... Time travel is a bad plot device because if you go back in time to solve a problem, even if it works, you are left with the paradox of not having any motive to go back in time in new timeline. This alone means the only rational plots involving time travel are ones that don't go as intended (red angle going back and failing to change the future in new discovery checks out so far for instance, as their goal was never achieved, as do MOST dr who story lines as he is just stumbling around and often not going somewhere to solve a problem), or where the time traveler is traveling for the sake of seeing time, running from something, or some such... You can't pull a janeway and go back to fix a problem.
Timeline are what you make them. If you go back in time to kill your grandfather. You just created a new timeline where he is dead. In your time line he still alive
I recommend the light touch theory. Such as over powering household electric wiring causing a minor fire to claim insurance money. As for the fixed points in time, are in my eyes examples are Albert Einstein father of relatively, or his famous letter to Roosevelt. Hitlers fourth Reich. Post media television POTUS Ronald Reagan, time selected him as President cause he had to perform good on Television to keep maintain world order and a smooth transition to a post cold war millennium. These are fixed points in time. Hypothetically speaking the unraveling of the ball of yarn results?,, I foresee two possibilities,, it will all work out in time😉 or its the sound of smalls stones effect,, hence causing a unstoppable avalanches in the mountains resulting in a avalanches everywhere else. Each collapse of fixed points, creates a space time fracturing paradox. The results of which could cause a chain reaction that would unravel the very fabric of the space time continuum, and destroy the entire universe!!!! Granted, that's a worse case scenario🧐. The destruction might in fact be very localized, limited to merely our own galaxy.
@@MistedMind No one except by a very obvious implication, since there's only show originated by CBS currently out anywhere...... unless you feel like TOS and TNG remastered ruined continuity? Like, I agree that all of Trek has had plenty of continuity issues (Data's rank in All Good Things for example). I don't think it's uniquely a thing Discovery had to deal with at all. But the original comment's intent was very clear nevertheless, y'know?
as Douglas Adams pointed out in his Hitchhikers books (the third one i think) that time travel by its very nature was/would be discovered simultaneously at every point along the space time continuum past present and future...which in as of itself could be considered something of a circular temporal paradox...
@@scottmantooth8785 Also I believe it was Adams who explained that all the supposed problems with time travel - killing your grandfather etc - pale into insignificance when you try to figure out the correct tense to speak in!
To be completely fair in doctor who they more often than not just blame it on a ripple from the time war since it was such a massive scale temporal war
That was spread across the universe, with both sides constantly altering events, making the relative time much longer. It was that bad the entire Time War timeline was sealed away from the rest of the timeline
Perhaps there is an alternative to complete alteration as proposed in the bridge scenario? Instead of tragedy, you could have narrowly avoided tragedy. Say 10 cars plunge into the water and their occupants are destined to drown to death. You could have a potential standby team nearby for the event and have them coordinate in such a way that all the occupants are rescued or resuscitated. Instead of complete tragedy occurring, a failure in construction parameters caused the near deaths of 15 or so people who were luckily saved in time. Instead of remembering 9/11 for the towers, it could be remembered for how close the planes came to hitting before the controls were wrestled away in time. Instead of Vasili Arkhipov voting with the rest of the submarine crew to launch the nukes, he could've voted against it and prevented World War III. Oh wait, shit, wrong timelime.
OR, force the bridge to collapse when no one is on it, but make it look like the original accident. People now improve the design, knowing it is flawed, but also grateful no one got hurt in the first place, because you made sure the collapse happened with no one on the bridge. Win-win.
But what if yiy save the people that would/should have died and one turns out to be tyrant that in the long causes the death of tousands or millions of people; some of which would have made great contributions to the good of mankind b7t are not thers to make those contributions.
I'm not saying that someone should go back in time to save lives. I'm saying that there are better ways of intervention. The thought of someone potentially going on to murder thousands as a result of survival isn't lost to me. That's timetravel 101. What I'm trying to get across is that there is a more efficient solution (if you so chose to go back) that could not only give people cause for concern, but also avert tragedy. As Matt pointed out, you could have the bridge collapse on its own. But I personally think parking all those empty cars on a busy bridge might arouse too much suspicion.
In a recent episode of "Legends of Tomorrow" (about a bunch of time traveling Super-Heroes), the character Constantine finds himself in the same bar as his bastard father, long before he was born. He tries to kick his father so hard in the balls that he becomes unable to sire children, but as soon as he tried, he blinked out of existence, only to reappear a few feet away, confused and startled. One of the other members told him that the universe has a 'Ball Kick Paradox", it simply won't let someone interfere in their own timeline enough to prevent their own birth (of course, this show has made many rules, only to break them later, much like Dr. Who ^_^)
Did You see, the one, in witch Constantine ancestor was some powerful mage, yet his father was no one, which mean if they (his lineage) had some power in magic and in land, they lost it all a long time ago.
Yes, I love sci it movies with this premise. It makes it so that no matter how hard they try, the time traveler can’t interfere with events that affect his existence, to the point where every physically possible event will prevent it from happening.
The original series Who episode Day of the Daleks with the 3rd doctor gets involved with Time traveling Daleks who conquered the Earth after a 3rd world war. The gureilas decided that the peace conference that failed started the war that allowed a weakened Earth to be defeated. They stole the technology of time transference and traveled back in time to the peace conference. They planned to kill the diplomat who brought everybody together believing that he intended to derail the conference deliberately. Instead in their attempt the Daleks detected the time trace and showed up to stop the gureillas and in the process the house where the conference was held was blown up. Destroying the last attempt to prevent the 3rd world war. Thus causing the very war they tried to stop. A predestination paradox was created. Had the guerillas not traveled back, neither would the daleks. There would be no explosion. The conference would go ahead. Peace can reign. The Earth wouldn't have been conquered and there'd be no guerillas to acidently start the war.
your bridge collapse problem sounds like a simplified version of Star Trek Voyagers' Year of Hell. with Annorax trying to correct a tragedy in his past but never quite managing the perfect outcome.
The answer, as with all Krenim Temporal Incursions, was to erase the Incursions themselves. The Krenim Timeship could only Remove, never add or restore, and thus could never fix what it had done till it, itself, was removed.
I recommend the light touch theory. Such as over powering household electric wiring causing a minor fire to claim insurance money. As for the fixed points in time, are in my eyes examples are Albert Einstein father of relatively, or his famous letter to Roosevelt. Hitlers fourth Reich. Post media television POTUS Ronald Reagan, time selected him as President cause he had to perform good on Television to keep maintain world order and a smooth transition to a post cold war millennium. These are fixed points in time. Hypothetically speaking the unraveling of the ball of yarn results?,, I foresee two possibilities,, it will all work out in time😉 or its the sound of smalls stones effect,, hence causing a unstoppable avalanches in the mountains resulting in a avalanches everywhere else. Each collapse of fixed points, creates a space time fracturing paradox. The results of which could cause a chain reaction that would unravel the very fabric of the space time continuum, and destroy the entire universe!!!! Granted, that's a worse case scenario🧐. The destruction might in fact be very localized, limited to merely our own galaxy.
So when Rick brings up the grandfather Paradox, who else immediately thought of that one Futurama episode, where the Planet Express crew ends up going back in time to Roswell, New Mexico? And yeah, predictably Fry's grandfather dies horribly in a atomic bomb test, leading to the hilariously disturbing consequence of Fry, having sex with his grandmother and thereby ensuring his own existence.
"Time travel: It's a cornucopia of disturbing concepts" You should watch this German Netflix-show called "Dark". Some of the concepts are truly disturbing and difficult.
Honestly, I've always preferred the concept that any time travel immediately creates a new timeline/universe entirely separate from the original one. You know, you can go back and kill your own grandpa without (time-related) consequence, because the moment you stepped out of the time machine you were already in a newly created universe. That's not *your* grandpa you're killing, that's the grandpa of another now non-existent version of yourself. Lets you explore all that fun time-travel stuff, without worrying about the paradoxes that get more and more complicated and convoluted the more you think about them.
Yet the many worlds interpretation of string theory has been disproven many times. Its makes good scifi but in actuality is wasteful and makes anything & everything pointless.
@@MistedMind his statement is incorrect because string theory as a whole was proven to be Incorrect. however the Kopenhagen Interpretation of Quantum physics , which postulates a different many world's theory was never disproven.
@@karlfranzemperorofmandefil5547 it's not really that string theory was "disproven". It's more like it doesn't produce predictions that can be falsified, which makes it a non-(scientific-)theory. But it has amazing math, and some very thought provoking concepts which might still prove useful. At least that's how I understood Matt O'Dowd on PBS SpaceTime
personally I think more along the lines of 'when you travel in time, you're no longer in sync with the timeline, and so are unaffected to changes in the timeline.'
Another type of "paradox" , invented by Sir Terry Pratchett, may he rest in peace, was for his Discworld book series. It was called "The Trousers of time", basically, it's where you go back in time, but for some reason, go to a "diverging present" or "down the wrong leg" on the return journey and enter a alternate timeline by mistake.
@@DyrianLightbringer roughly speaking, yes. But the problem is that if you travel back in time, you can't return to the same "present" you came from. The action of time travel means that you have already changed the past before you get there.
Depends on how you look at it..predestination paradox takes your time travel into account, and the timeline you started in is *already* the result of your meddling in the past.
All actions during time travel produces a paradox. If the traveller corrected the flaw and the tragedy never happened then why would the traveller come back to the past to correct a flaw that never happened?
Then why would one go back in time to fix something that never became a problem. Thus you never go back to fix the thing you went to the past to fix in the first place.
@@WAX1138 you would have went back but your time line never played out time is not a line but a branch of choices go left instead of right or go right instead of left. That's overly simple yes but out comes would change non the less
The many worlds interpretation of string theory has been disproven many times. While it makes interesting scifi it is ultimately a wasteful use of energy and makes everything pointless. That said modern string theory does not support it, so there are not multiple versions of the universe and there is only one timeline. But I don't expect you to now this bc "magnets how do they work" and its not entertaining enough for you.
@@WAX1138 thats nice and all about string theory but thats BS anyway ( bad science ) im not talking about string theory. its based on the idea of the infinite universe no beginning and never ending. there is no need at have multiple versions of the universe you would be in the same one just displaced in its time. time can branch out in to multiple places its all the same time just different areas of it time is infinitely long and infinitely wide and about your red herring fallacy does not strengthen your argument. ps. i dont fallow there religious ideas religious. so please keep on topic i dont make off the wall comments on your pic/name. no need to its irreverent to the topic. whats next my grammar or lack there of?
You get arrested for the incident in the alternate universe. And that universe will have to cancel out matter of equal mass to yourself. Meanwhile, the past was unaffected in your own universe.
You then hit the 2nd part of that problem, what of those who were destined to die that day? And then multiply that by the generation of children who are now born due to that kind act. Do they create a better future or worse? Did one marry someone they normally wouldn't have met preventing them from a fated destiny. Sometimes the kindest thing is exactly the wrong thing made 1000x worse as the events ripples out from the action. (In Star Trek: look at what happened when Dr. McCoy saved Edith Keeler. Who might not even had walked in front of that truck had Kirk and Spock not been there and then greeting an old friend.) You've got good intentions, we know what destination uses them as paving stones.
Huh. That example reminds me of the Silver Bridge disaster in Point Pleasent, West Virginia, USA which had a fatal flaw and the disaster lead to sweeping legislation, changes in construction, inspections of old bridges, and so on. It's also the event that is tied up in Mothman lore and some lore said that it chased/fightened/delayed a bunch of people that night who would have been on the bridge at the time so that it ended up being fewer people than expected on the bridge when it collapsed - more cars with fewer people in them and heavy trucks. Interestingly enough pretty much the same entity supposedly showed up as the 'Freiburg shrieker' (Black color, winged, red glowing eyes) in Freiburg, Germany in 1978 where it scared off a number of miners before a mine collapse. Red Eyed Angel? :p
No. In Angels Take Manhattan, the Doctor couldn't go back to that time period because of the time lines being scrambled. It's not established WHEN Rory and Amy were sent by the surviving angel, but it was a "fixed point" because if the Doctor went back to see them, he might inadvertently impact their known deaths and burial in New York. As he pointed out earlier, you can't change your own history once you know what it will be. This explains why the Doctor traveled without "reading a history book" in The Girl That Waited. His "ignorance" of what specifically happened somewhere give him latitude to mess with time as he knows when something is a fixed point and when it is not. Foreknowledge basically restricts his freedom to interact in events.
It was specifically stated in the episode that the Doctor couldn't go back to that time anymore because everything was "scrambled" (I forget the exact wording used offhand). Hell, he had trouble getting through the _first_ time, at the beginning of the episode, when they were going to rescue River. Your logic makes little sense, because the Doctor has visited MANY people whose time of death is already well known. He's even tried to prevent some notable deaths.
@@JakkFrost1 With some considerable effort he did get through. What makes the ending so definitive is because Amy chooses to follow Rory, entering/making a fixed point in history (a detail that is mentioned in-story: "You are creating fixed time! I will never be able to see you again!"), permanently locking the Doctor (and River) out of ever seeing or travelling with her ever again.
what I never understood is why the Doctor didn't just travel to say... 1940s New York. He sees Amy and Rory's tombstones read their ages upon death, but not the dates of their deaths. He could easily go to New York at any point OTHER than the scrambled time period, visit, or even pick them up, have more adventures, and return them to New York later on. All that their thombstones confirmed was that they died in New York and were 84 and 87 years old when they died.
@@DyrianLightbringer Are you familiar with the Reverse Series 7 theory? That for the Doctor, the first half of the series plays backwards? There's a few points that suggest he tried visiting them, the first being in opening scene of The Doctor, the Widow, and the Wardrobe tying directly into parts of The Name of the Doctor. During the course of Name, the Doctor attempts to go to Trenzalore, a place he should never ever go, and he has to (IIRC) disable some safeguards to do it. Despite this, he can't materialise safetly and arrives in orbit, and has to disable the engines and fall into the atmosphere just to get anywhere. In the Not-Narnia episode, the Doctor is in orbit above Earth on an exploding spaceship, and falls into the atmosphere. No TARDIS in sight. The TARDIS is on Earth's surface somewhere. But the time period is exactly December 25th, 1938. The exact year Rory was first sent back to during Angels Take Manhattan. Perhaps he was trying, and that's why he was there: the TARDIS refused to get any closer, stranding him in orbit after the HADS system (later used in Cold War of the same series) activated, and that's how he knew/worked out how to "land" Trenzalore under similar restrictions. Afterwards, he ended up resigned to never seeing them again, but found his loophole by visiting their 2012(?) selves living in London, eventually leading through the slow goodbye of Power of Three/Town Called Mercy, and leading into Asylum of the Daleks. It's one theory at least.
@@DyrianLightbringer The difficulty of that task aside, let's look at it this way: if he picked them up in 1940's NY and they were a fixed point (the awareness of their tombstones), what would happen, if said "fixed points" died on an adventure somewhere? Would he be able to return them to their fixed death point? Wouldn't that create a paradox? How could they die in like 1940something, when they died with the Doctor somewhere, lets say on a different planet? You know, he can do anything, but he can't assure their safety 100%. If he can't keep them safe forever, how could he be sure not to create a paradox by allowing their deaths outside of their fixed point?
Some notes: A more general definition of the Grandfather Paradox is: You can't go back in time and remove the conditions that made you go back in time. If you think about it, this includes most if not all intentional interferences with the past: If you prevent the bridge collapse tragedy, you would never have the idea to go back and prevent it in the first place since it didn't happen, and so on. (Note that this does not apply to models where this causes alternate timelines.) I think people tend to get too literal about these things: It doesn't _have_ to involve erasing yourself by killing a close relative. Contrary to what some people assume, causal loops are not actually time paradoxes - they are weird and counter-intuitive, but do not violate causality. (I know you didn't claim this in the video, I'm stating it for the record.) This even includes the Bootstrap Paradox, which is an _ontological_ paradox rather than a causal one. The Lucky Charms examples used in this video are actually not very good examples. For the first one, there is no reason to believe the message from the future is the reason you end up sending that message. Future you may simply have realized he forgot to buy Lucky Charms, which was the original reason he sent the message. Then, the version of you who got the message sent the same message simply because he knew he was supposed to. This would actually be an example of changing time while maintaining causality. In the Bootstrap example, the main problem is that the box of Lucky Charms would degrade over time so it would be an older box in every iteration, meaning there will come a point where you can no longer send it back in time which means the event logically can't happen. It works better when time travel simply causes a series of events to occur that circles back around. See Heinlein's By His Bootstraps, which is the origin of the term. On that note: Time loops can in fact have sensible beginnings and endings and don't need to mess with causal events. For example: Say I'm hungry but my local pizzeria closed half an hour ago, so I go back in time one hour and get my pizza. Then I head home just as my other self goes back in time, at which point I just carry on with my life as usual. I'd be an hour older than I should be but at least I'm not hungry anymore. In fact, causing an event that leads to you causing that event is pretty much the definition of a Bootstrap (or closed) causal loop. So, both of your examples were in fact intended to be Bootstrap paradoxes.
In the Netflix show "Dark", the machine used in the time tunnel is stuck in a Bootstrap paradox loop. It gets repaired each time, at least. (Stuck in a 30 year repeating loop.)
Who cares? If time can be altered, then those are all just parallel alternatives. New pasts and new futures get created and converge all the time. Just pick one you like.
Tell that to the many beings beyond the multiverse in DC Comics. Not that doing so would do any good. Many of them do not care even when they do understand. Or some are doing because of what you say.
As per the bridge accident there is another problem. People could die whose offspring make great contributions to the future. Or people might never be born due to the non-collapse. wheels within wheels.
Time travel will never happen as it's completely impossible. With the exception of Dr. Who, I hate, hate, hate time travel in sci-fi shows. I just makes everything moot. Time travel would create alternate realities every time even one little thing changed, so what would be the point? Your original timeline is still there and now there is another, a whole new universe created by one time traveler.
@@DrewLSsix Not sure I believe this. Is it at the atomic level will genuine mass or just information that has time traveled. I'm not referring to the space time relativity but genuinely having something go BACK in time.
Not to mention, those tragedies are in the past, they are important to our history and our development. Changing them is a bad bad bad idea. But as you said, I agree it's impossible. Mathematically they have some models for it, but it requires impossibilities to exist.
@@pupip55 I've looked into it quite a lot. It's nothing but thought experiments and mathematical models that again, require impossibilities. It's not happening, and our world is far better off for it.
What about the Philip Fry version of the grandfather paradox. My personal favorite bootstrap paradox is the watch form Somewhere in Time (also my favorite "chick glick").
I think the sci-fi network continuum got it right. Time travel happens on an alternate timeline. Like on back to the future, Biff asked Marty why he wasn't in Switzerland. Because the Marty that belonged in that timeline was at the European boarding school. Broke ass Marty was screwed, he made his timeline cease to exist. That 4x4 wasnt his it was rich marty's along with that home and that family.
In reality the grandfather paradox couldn't actaully happen, say you used a gun, the gun would miss fire, probability would narrow to only allow events that don't break causality and because you've already physically observed and existed in the future where it didn't happen (non physical observations have different rules). Causality loops are basically the only way to actually change time without breaking other rules, as long as you tell your new past self to go back and make the changes. The biggest problem with time travel that is always overlooked is changing small things that can ripple into huge changes that aren't predictable (think of a river during rain, all the drops create ripples, those ripples bounce off of each other making new patterns but remove one rain drop and over time the pattern would have completely changed). Morally if you change time you will be wiping people from existance for your own needs and one could argue whether it is right or wrong. Saying this i love time travel in scifi, especailly doctor who. As for star wars, i agree that it has a fixed timeline but i think that is more due to the force and how it influences the star wars universe as an invisible guiding hand.
Bridge problem? Fabricate the conditions that trigger the collapse in a safer time. Unoccupied or significantly less occupied. Bonus points for nearby press.
A spit second before the bridge collapses, teleport everyone about to die to a far away location. Have them live out their lives outside the eye of history. Meanwhile history proceeds as if everyone dies and mankind learns the lessons from the bridge collapse
Can't agree. This bit about not knowing the outcomes or generating a less than optimal outcome by saving lives reminds me too much of the following: Imagine you spot a child about to die in a burning building. Do you try to save them? Now, the answer seems obvious: Yes! But perhaps this child will grow up to be a serial killer or the next great dictator. You don't know what the long-term outcome of saving the child will be. Does that change what the moral choice of action would be? I think not. We should save when we are able to save.
I always saw the fixed points in time like wave node points on a plucked guitar string. The string itself is a timeline. As the string waves back and forth, the timeline itself is constantly changing. Yet, the node points don't move and are therefore fixed. Points on the time line that are closer to the fixed points can't move as much, so while they may not be fixed, the also won't (or can't) change as much. This is what I normally use as the basis of my explanation for the flow of time in Doctor Who.
"I am YOU from the future. There's no TIME to explain!" /me shoots putative future me "I think you just shot future you." "If he was really future me, he would have known that was going to happen."
Is not knowing where the Lucky Charms came from the main problem with the Bootstrap Paradox? I would think it would be the fact that the box of Lucky Charms would have been expired by a billion, trillion, zillion years, if not infinite. Those Lucky Charms will be the only thing to survive the death of the universe.
Solution for the bridge: ensure no lives are lost by ensuring a /very/ expensive piece of equipment is being transported over the bridge at the time of collapse. Motivations to fix the fundamental problem are never addressed more quickly when money is lost, likely ensuring the structural problem is found and fixed all the same. But the point stands, some events 'must' occur, insofar that large scale changes to the timeline could equally result in an unintended grandfather paradox in the end. Every 'fix' (kill hitler, save the bridge, etc) increases the risk of creating a paradox. As for the network of twine on the wall, that's a really nice way of visualizing 'fixed points'. I look at it differently though. Imagine spacetime as a stretchy/rubbery medium in which time travel incursions ripple out. There is some inertia to cause such a ripple. Small ripples (minor tweaks to the timeline) don't radiate out very far, and require little energy/effort to initiate. Larger ripples may leave longer lasting changes, and require all the more initial 'energy' to catalyze. Fixed points are those events that would alter most everything on the fabric, with an almost insurmountable resistance to causing them in the first place. In stead of the entirety of spacetime changing from that point out, the fabric finds another local fold and dissipates the 'wave' of change, keeping it mostly the same as when you started.
The Star Trek TNG episode: "Cause and Effect" in which the Enterprise is caught in a temporal loop was fine until the end of the show. Enterprise encounters a "temporal anomaly," a ship from the past emerges and impacts them, the Enterprise is destroyed. The explosion sends the ship back in time i.e. resetting time. A temporal loop is created. The crew manages to detect their situation in the surrounding tachyon field and send themselves a message; thereby avoiding the explosion and escaping the loop. OK; fine so far. But then in the final scene, they discover that 17 days have passed while they were caught in the loop and they reset their clock. This made NO sense. NO additional time should have passed. Their clock should not have had to be reset. I was peeved!
I was aware of the Bootstrap and Grandfather Paradoxes, abs also the Causal Loop. As for the bridge problem, I’d probably just let it happen; better to leave the timeline as it is than to risk making it worse.
Let the bridge collapse but make sure there’s no/little traffic on it my posing as an authority and closing off or partially blocking the bridge. Of course this could lead to someone surviving who really shouldn’t because they form a terrorist groupie or become a mass murderer or something...
solution to the bridge problem: i would take inspiration from a real world event where a architect student discovers a critical flaw in the Citicorp tower, now called 601 Lexington in new york, a flaw that could send the towering skyscraper falling down and wiping out nearly a entire city block, the construction was already well on its way and the building was actively in use on its lower floors that had been completed, they had to do emergency reconstruction day and night. just like that time, i would wait for the bridge to be well on it's way to completion, perhaps even wait for it to be completed and opened for use before pointing out the flaw, as the bridge is actively being used and no one knows when it will collapse, fixing it will become a VERY dire emergency as to avoid a disaster, this situation would also create a critical need for new regulations to be put in place to avoid construction of such flawed bridges again. this may not work in all scenarios, but at the very least, that bridge wont be collapsing anytime soon. now, this is however not the scenario i would worry about the most, the one thing i would worry about the most here is people using time travel to intentionally sabotage things to cause disasters to take place, like for example, someone going back in time to put that flaw there in the bridge with the intention to have it collapse causing unknown amounts of dead, hell, i myself would probably be guilty of something like that myself, intentionally creating scenarios that lead to disasters with potentially hundreds if not thousands of deaths, all for the purpose of taking out a singular or a handful of individuals that i have determined to be bad and in need of removal before they become a problem.
Or you could time travel back, run for government work to get regulations passed that would have been passed anyways, and yes governments do this all the time without death of people. And governments love it becuase they can then get thousands of dollars for these regulation violations. :)
My solution to the bridge problem. Say to the engineer “‘ay mate! Don’t you think it is good practice to over engineer your bridges, you never know what is going to be traveling across it in the future.” And if he doesn’t see that as common sense I’ll straight out tell him I know what will be on it in the future and he needs to overengineer it and hopefully he becomes an advocate for over engineering everything to do with people, either for fear of a time traveler getting on his case or because he genuinely sees it as common sense.
I think your bridge analogy is best exemplified by the Voyager episode Year of Hell, the Krennim captain trys for centuries to correct his own corrections to time each time adding more variables and making it harder to get the desired effect.
My favorite "thinking about time travel" moment was from an Avengers comic. They explained how Dr Doom's time machine in Fantastic Four issue 5 was the first time machine that could change the past (due to a special "doom circuit"). Then they went over every still-active time travel anomaly, and ended the presentation with "if I could I'd go back in time and assassinate Doom before he invented the Doom Circuit...of course for that to work I'd have to use a Doom Circuit, so..." Everyone in the room laughs at that, except the group's resident alternate reality traveller Miss America. She gets this haunted look and says "don't even joke about that. I've seen timelines where the Avengers tried that. It was like spaghetti. Spaghetti that screams."
There is another work around for time travel to work without the risk of paradoxes and keeping temporal stability: The Multiverse Theory, basically stating there's a universe for EVERY possible outcome. For example, let's say you go back in time and kill your grandfather. When you travel back to the future, you don't travel to your own future, but a future in another universe fitting the criteria of the events you played in the past. This means the original timeline is still existing, it's just that you've traveled to another universe that fits the criteria you created from alterations in the past.
@@Ozzy_2014 Pretty much, ensuring that something like a paradox won't lead to a complete collapse of the space-time continuum. BUT, this also brings about a kind of moral issue: If there's a universe out there for EVERY single choice that was, is, and can be made, does that mean that we are destined to carry out criteria to fit with the model of a universe, and that our choices are irrelevant? Personally, I think a degree of ignorance is helpful in this instance, as it helps to focus on the present of your choices instead of thinking you don't have any choices that are meaningful, in that the universes that are alternate choices don't come into play, UNTIL the choice is made. :)
you're making the assumption that your grandfather (pending) is not a better shot than you and had not been previously warned by an alternate version of himself of your arrival and when to expected it...you would be walking into a temporal ambush...
There's a good short story that goes over the strange effects of a bootstrap paradox: All You Zombies. It's pretty cool, although the implications aren't as fun to think about...
and actually all you zombies(hats off heinlein) was translated into a movie called predestination, and they actually did an amazing job with it . . . got all the details in, most likely because it was a short story XD . . . love heinlein
If you could either use the knowledge of when the bridge will fall or cause the bridge to fall in away that wouldn't look like someone did it. Then set it up so the lose of life is much smaller or non with minor problems to traffic and access to the bridge before it falls. No one can tell the butterfly effect from this but it should still allow the impact of the event to carry most of the weight it would of other wise had and still have an event that would cause you to come back to change.
To the Bridge scenario: Instead of directly intervening in the bridge construction, you go to a time slightly before it, and release a "paper" or "news" about how that particular bridge design is flawed, describe the better design, and push for regulations to enforce that design. You save the lives, and you ensure the safer design is put into place.
Yes but what if the changes (specifically the innovations) were brought about only because the engineer lost a loved one in the incident? Sadness and problems are powerful forces in driving people. Far stronger and more lasting lessons.
You ignored Stargate. They had an episode, 1969, where they accidentally time travelled. Before they entered the Gate, Hammond gave Carter a folded note and told her not to open it. Then a young Lt Hammond found the note after the team was arrested. It was written to himself, telling himself to help the team. After he finds the note by him to him, he keeps the note in a desk for 35 years or so without telling anyone about it. The day of the accidental time travel, he pulls that note out of his desk and gives it to Carter, telling her not to open it. She then ends up arrested and in the custody of a young Lt Hammond, who finds the note by him to him telling him to help the team. He keeps the note in a desk without telling anyone about it until...... Wait..... WHO WROTE THE NOTE!?!?!?
@@BigJeremyBeyer let's not forget that time they buggered the timeline so bad that the closest they could get it back had fish in O'neill's pond. Or the time Shepard was stuck in the future and had to travel back with help from hologram ghost McKay
I always liked that Blink is one of the best Doctor Who time travel stories, in spite of the fact that time travel in almost every other episode of Who doesn't even slightly work like that.
1:46 aka my problem with harry potter and the Prisoner of Azkaban, harry cant save himself as he was dead the first time he needed saving. As for the bridge problem im going to have to quote spook on this one ""the needs of the many, outweigh the needs of the few"" id most likly let the bridge fall, yes we would lose lifes but in the long run it will save 10x maybe 100x the lifes we lost, but i know they wouldnt be a comfort to the ones that lost loved ones.
On top of the paradoxes, there is also the moral component. Let's say that you have a nephew who is 7 years old, and you decide to change something important 8 years ago. The ripple effect of change, whether destructive or constructive would still be a change in future events. The odds of a specific egg being fertilized by a specific sperm is so astronomical that you might as well buy a powerball ticket and announce your imminent retirement as expect the same nephew to be born. Now, in the Dr Who example, Fate would dictate that this individual would be born as normal for some wibbly wobbly fate reasons, unless of course the father got killed for reasons. However assuming a completely chaotic system, you have prevented that 7 year old from ever being conceived. Is this murder? What if instead of this nephew, you get a niece a year after the nephew was supposed to be born, this 6 year old niece is now existing where she hadn't before in the previous time line. Does that erase the burden of pre-conception murder, and how would it be defined? Assuming only the time traveler is aware of this, no one would know. On a similar level, people's personalities and attitudes toward life are an accumulation of experiences and circumstances presented. If you stopped someone from climbing a mountain and take up mountain bike riding instead of climbing, they might be the same person with an athletic drive, but their personality and strategy to physical adventure is different, possibly resulting in a different enough personality that you might not recognize that individual anymore compared to the original. Paradoxes must be avoided, but morality in time traveling is so socially complex that someone might suffer from psychological distress from the experience. In the end, a time traveler would have to accept that everything beyond the moment of change is going to be completely different from what he knew, and any and all changes are both "his/her fault" and "not his fault" as events would play out according to the new variables. Yes the traveler set in the new chain of events, but he would only be responsible for the initial change to life's variables, how everyone else reacts to those new variables would be difficult to take credit for.
Wouldn't the very act of entering a place and interacting with the people (for better or worse) be altering them? Yet that is what humans do day in and day out. I could choose to meddle in a marriage, distressing generations of a family. I could drive carelessly and run down somebody's child. I could be a horribly obnoxious racist pig and hurt people. Or I could be polite and decent and helpful. Everything I do alters those I interact with as they interact with me. It's a great sci-fi notion of timelines and do-overs and all that, but as far as I can tell each individual experiences each moment only once whether time is experienced normally or not. I'm not sure if I could time travel to a period in my own past, because I have already experienced that time. It is fixed for me.
To solve the bridge problem, I would figure out a way to keep all the people killed in the malfunction of the bridge off the bridge. I think the easiest way to do that would be to some how schedule "Construction" that causes both sides of the bridge to be blocked off just before the time of the malfunction. The bridge would still collapse and there would be an investigation into the cause. I would find someone who could make a big deal about what would have happened if the bridge hadn't been blocked off. Somehow, block off the bridge, even a carefully "engineered" vehicular accident on both sides could work.
DawnTreader except, what if blocking the bridge off means that at the time the bridge is supposed to fail there isn’t enough weight on it to cause the catastrophic failure; so it doesn’t at that time. You haven’t prevented anything, just changed when it would happen.
I Am advent watcher of this channel and I will say that it is definitely one of my top 5 channels that I watch faithfully. Saying that I have watched this episode at least 10 times and I love the examples for time travel that u make. Even a complete novice that watches this with no understanding of time travel or a watcher or either show will come away with a pretty good understanding of time travel. I love the channel and I love Rick so please keep up the great work.
When it comes to the "bridge paradox" I wouldn't interfere, I would let those that died die for the sake of future continuity, but if there was a individual whose death would greatly impact humanity ex:a cure for "insert cure" I would interfere in as much as to deviate said individual away from that situation even if if this cure occurred decades down the road.
Great video! One of my favourite books is Isaac Asimov's "The End of Eternity", which addresses the bridge problem. The Eternals travel through time (but not before the 27th century, when the first time machine was created), altering history to improve the lives of humans. They have a policy to cause the "Minimum Necessary Change" required to achieve the "Maximum Desired Response" - they'll misplace a scientist's notes, or burn out a circuit in a diplomat's car, resulting in a calculated butterfly effect to avert a catastrophe or unwise invention. This way, they minimise the disruption to the timeline - but a major plot point is considering whether such disruption can be ethical at all.
Honestly the whole paradox theory is just to try make things complicated. Time travel will just be something as simple as travelling to an alternate reality where the things you alter occured. As soon as you travel back to the period, time has already altered allowing you to be there, so it's safe to say this is no longer your reality. Rules about time travel are only really there in tv shows and movies to limit the use of it or simply to make it a less common occurrence, if the Doctor can alter time as he or she sees fit, then the show wouldnt really be that great.
I think one of the most confusing paradoxes is the predestination paradox, the one where a past event is dependent on a person from the future coming back and creating that perfect causal loop. It’s incredibly similar to the bootstrap paradox, but the common example for predestination is going back in time to discover you’re your own great-grandparent
People never seem to actually get what the concept of a paradox is supposed to do, everyone thinks it’s some cinematic crisis like fading away in Back to the Future.
I find the best example of explaining a predestination paradox is this: Your parents die in a hit and run automobile accident when you are a child, you crawl from the wreckage and memorize the features of the car. Obsessed with preventing this tragedy you resolve to spend your life to save them, by building a time travel device. You succeeded and you travel to the year in question but you arrive 10 minutes later than expected. As you are racing towards the intersection where the crash occurs so you can place your care in the road, put the hood up and feign disabled causing your parents to slow and avoid the hit and run. you race to the scene and as you come to a four-way stop, you slam into a car spinning it off the road and rolling it. Realizing that any impact you have on the timeline will be devastating you flee the scene. In the rear view mirror you witness the only survivor crawl from the wreckage, you as a child memorizing the features of the car that killed your parents and resolving to make sure it never happens. Thus completing the loop. Your parents died because you witnessed them died, the action you take to prevent the tragedy becomes the cause because it was in reality always the cause, no time traveling you trying to save mom and dad, no car to spin their car into a ditch and roll it.
