Category
😹
FunTranscript
00:00 Of all the sci-fi superpowers and spec-fiction fantasies that are out there, the interest
00:04 in time travel just refuses to die down.
00:07 And with good reason.
00:08 Because what could be cooler than moving not just through the three dimensions of regular
00:12 space, but through the fourth dimension as well?
00:15 It's no secret that there have been some real-world efforts toward achieving time travel,
00:19 too.
00:20 And to some degree, there are a select few who have technically managed it, such as those
00:24 who have spent time off-Earth, on board the International Space Station.
00:28 But while that's all very impressive, it's not exactly Doctor Who.
00:32 We've still got a long way to go before "Back to the Future" is still actually
00:35 doable.
00:36 So what is awaiting us on the horizon?
00:39 This is Unveiled, and today we're answering the extraordinary question; will time travel
00:44 ever be possible?
00:48 Do you need the big questions answered?
00:50 Are you constantly curious?
00:51 Then why not subscribe to Unveiled for more clips like this one?
00:54 And ring the bell for more thought-provoking content!
00:58 Officially speaking, no one has yet travelled through time.
01:02 There are countless rumours, legends, and conspiracy theories, of course, including
01:06 claims of shady goings-on in New York State at the Montauk Project, more recently made
01:11 famous as the inspiration for the Netflix show "Stranger Things".
01:14 Also, in the mid-to-late 20th century, there were allegations of the Chronovisor at the
01:18 Vatican, an alleged time viewer capable of transporting users back to the crucifixion
01:24 of Jesus Christ.
01:25 And also, Deglacca, a supposed Nazi time machine said to have been built using alien technology.
01:31 But so far, there's still nothing, even remotely above board, to suggest that time
01:36 travel is, has been, or ever will be possible.
01:40 Arguably the best concept we have for use in a genuine time machine is the Alcubierre
01:45 Drive.
01:46 If it ever were built, it would utilise what are known as "warp bubbles" around a spaceship.
01:51 To allow that spaceship to travel at faster-than-light speeds without breaking any local laws of
01:56 physics.
01:57 Which then should, according to predictions, enable it to achieve backwards time travel.
02:02 With backwards travel being theoretically more difficult than forwards travel (which
02:06 technically should be manageable, if only we could find a way to travel really, really
02:10 fast, with or without a warp bubble), it all means that the Alcubierre Drive really could
02:15 be the key invention we've all been waiting for.
02:18 It's a shame, then, that it hasn't ever been built, not even in a true prototype form.
02:23 Leading many to label it "fantastic" on paper, but probably impossible in reality.
02:28 The problem with all time travel designs, including the Alcubierre Drive, is that they
02:33 typically require something that either we don't have yet, can't reach yet, or don't
02:38 understand yet.
02:39 Some kind of exotic fuel or material, or some massive frame of reference that's currently
02:45 beyond our capabilities.
02:46 Only we've known that time travel is theoretically possible since at least the days of Albert
02:51 Einstein and his revolutionary illustration of space-time as the true basis for the structure
02:56 of the universe.
02:58 Humankind may have suspected that time travel is possible for even longer than that, though,
03:02 given that it invariably turns up in various ancient texts, including in early Hindu scripture,
03:08 Buddhist teachings, and in some interpretations of the Bible.
03:12 However, from then until now, it's remained as physically impossible as ever.
03:16 We just can't work it out.
03:18 What's perhaps most concerning, however, for those who want time travel to be real,
03:22 is that there are no signs of the picture improving.
03:25 That isn't to say that our scientific knowledge is getting worse, or that our critical understanding
03:30 of time travel is dwindling.
03:31 It's more that there is no genuine, incontestable evidence of time travel happening in the future.
03:37 As with most things around this theme, it's a bit of a head-spinner… but when was the
03:42 last time you encountered someone, something, or somewhere from your future?
03:47 Or from the future of anyone or anything else?
03:50 Unless you're in the small minority that claims to have had a true brush with time
03:53 travel before, then the answer is probably never.
03:56 You've never seen time travel in action.
03:58 Which doesn't sound all that crazy… until you consider that there is a potentially infinite
04:03 amount of time stretching out in front of you, and there always has been.
04:07 For the sake of argument, let's put a number on it.
04:09 Let's say that there is and was at least another one billion years between the moment
04:13 you were born and the end of the universe.
04:16 The fact that you have never witnessed any aspect of the future bleeding into your present,
04:20 its past, arguably casts into severe doubt that anyone at any time is ever going to time
04:25 travel at all.
04:27 Because if they were, then wouldn't you, or your parents, or your friends, partners,
04:31 children, neighbours… wouldn't you all have met a backwards time traveller by now?
04:36 Starting this time from their future time just because they can?
04:39 It could be that the universe ends in one billion years, in ten years, in one trillion
04:44 years… it doesn't matter, because it's the same result.
04:47 No one is coming.
04:49 It boils down to a quite simple realisation; if time travel is ever going to be possible,
04:53 then surely it already is possible.
04:55 That's just the nature of the beast.
04:57 If time travel exists at any time in the future, then it by default is at least impacting the
05:03 here and now.
05:04 The invention of time travel would mark the moment in time that our understanding of time
05:09 itself disintegrates.
05:11 From that point forward, there would never be a past, present or future in quite the
05:15 same way ever again.
05:17 But we, the human beings on Earth at this very moment, are the past from the future's
05:22 perspective.
05:23 And, clearly, our status as such has so far shown no signs of changing.
05:27 Therefore, we might conclude that time travel will never be possible.
05:31 Except… that's also only half the story.
05:34 Or, an even smaller fraction of the overall potential.
05:38 Because fine, time travellers from the future haven't yet arrived en masse into the twenty-first
05:42 century… but there's some argument that that particular eventuality actually is never
05:47 going to happen.
05:48 Instead, the invention of time travel will represent a major cut-off point in history,
05:53 a truly incomparable before-and-after moment.
05:57 Some claim that time travel, if and when it does exist, will only ever stretch backwards
06:02 in time to the point of its invention… but not a second before then.
06:07 This means that as time travel hasn't yet been invented, it really makes perfect sense
06:11 that we also haven't been flooded with travellers yet.
06:14 Because as much as they might like to visit a pre-time travel age like our own, they physically
06:18 can't thanks to the inherent limitations of the time travel that they enjoy.
06:23 Another perhaps more likely possibility is that while backwards time travel is and will
06:28 always be impossible, forwards time travel isn't.
06:32 And to some degree, we know that forward travel certainly is achievable.
06:36 At the most basic, all of us do it every day, in increments of seconds, minutes and hours.
06:43 Since you started watching this video, your past self has transformed into your current
06:48 self, which is busily transforming into your future self, as well.
06:51 You can't go back to your past self.
06:54 You can't remain as your current self.
06:56 You're always on the brink of a new, future version.
07:00 Even in the time it took for me to say that last sentence, we've all moved into the
07:03 future.
07:04 And again.
07:05 And again.
07:06 But really, that's a bit of a cop-out.
07:07 And true forward time travel would presumably involve massive jumps into the future, moving
07:12 years, decades or centuries in just a couple of seconds' local time.
07:16 Will that ever be achievable?
07:18 Unfortunately, right now, it's not something that anyone can say yes or no to.
07:22 We will likely need to have made many major scientific developments between now and a
07:27 time when it might be possible, though.
07:29 For example, while we know that time dilation would theoretically set in for a traveller
07:33 in a spaceship moving extremely fast away from Earth for a sustained period of time,
07:39 we still have almost zero means of ever making that happen.
07:42 It's grounded in physics, yes, but it's still closer to a fairy tale in terms of our
07:47 capabilities.
07:48 Could time travel, instead, ever be possible for some other, more advanced group than us?
07:53 That's another question, and one with infinite potential answers.
07:57 Clearly, however, with no knowledge of any other intelligent group other than ourselves,
08:01 it would all be speculation.
08:02 A Kardashev Type Five certainly could travel through time.
08:06 For any civilization that can tap into the multiverse, it could use that to bend the
08:10 temporal rules as we see them.
08:12 But we are neither of those.
08:14 And so far, while we know and to some degree understand the fourth dimension, we're also
08:19 inescapably limited by it.
08:21 Until such time as we break into time itself, it's a painful paradox with no end in sight.
08:29 What do you think?
08:30 Is there anything we missed?
08:31 Let us know in the comments, check out these other clips from Unveiled, and make sure you
08:35 subscribe and ring the bell for our latest content.