Travelling Back In Time? w/ Stephen Hawking & Neil DeGrasse Tyson

Travelling Back In Time? Explained by Stephen Hawking On Neil DeGrasse Tyson StarTalk National Geographic NatGeo Stephen Hawking Interview #shorts #startalk #ndt #universe #university

[Universe_University]

📚 Buy Neil’s Books Here:

Starry Messenger: Cosmic Perspectives on Civilization

Astrophysics for People in a Hurry:

Astrophysics for Young People in a Hurry

Cosmic Queries: StarTalk's Guide to Who We Are, How We Got Here, and Where We're Going

Origins: Fourteen Billion Years of Cosmic Evolution

Letters from an Astrophysicist

Welcome to the Universe: An Astrophysical Tour

Accessory to War: The Unspoken Alliance Between Astrophysics and the Military

Death by Black Hole: And Other Cosmic Quandaries

The Pluto Files: The Rise and Fall of America's Favorite Planet: The Rise and Fall of America’s Favorite Planet

Space Chronicles: Facing the Ultimate Frontier

A Brief Welcome to the Universe: A Pocket-Sized Tour

The Sky Is Not the Limit: Adventures of an Urban Astrophysicist

[citizenvulpes]

People in the comments not realizing Neil was making a joke is just painful.

[cwbb]

The way Hawking looked at Neill when he said “ all the have to do is create negative energy density stuff” lmfaooo

[NKBlazer]

My boy Neil coming back in time to subtly let us know we can go back in time. 🤝

[McBethklok]

NEIL:Is it possible to unscramble an egg?
-NO
NEIL: So all we have to do is invent unscrambable eggs

[robertyates]

My favorite theoretical physicist, is Dr. Sheldon Cooper, and he says it's not possible.

[ArshikaTowers]

If time travel is correct, perhaps the roads that must be present to time travel are only paved when time travel is created. So, once time travel is created, you can move forward and back in time, but only as far back to when the machine was created.

[seanspartan]

If negative energy existed, we could create an unlimited supply of positive and negative energy out of nothing...

[chrisuzumaki]

The look that hawking gave Tyson at the end was pure stfu😂😂😂😂

[InfectedMoo]

If there are multiple timelines, it would never be possible for us to perceive an arriving time traveller, only a departing one, as the arriving time traveller would be landing in the newly created timeline.

If this is the way time works, I suspect that if anyone actually tests a time travel device it would be thought to be a failure even if it succeeds, because the test pilot would be returning to the present in an alternate timeline, so from our perspective they’d simply vanish into nothingness and never return.

[barisdogru]

Neil says that we would've met someone from the future by now, but there are 3 things that he potentially misses. 1. The furthest back you can travel back in time is to the moment the first time machine was powered on, because there has to be something on the receiving end. 2. Even if someone had traveled back to our time, that person would probably keep a low profile, as to not cause complete armageddon, as the general day to day flow of the world would be in shambles. 3. There are infinite times that a person could time travel to, so the possibility that a person traveling back to our time would be one out of infinity.

[justadummy]

That’s assuming we could travel backwards to a time in which the time machine didn’t exist, perhaps the barrier between us & them is the fact that we don’t have time machines, which means they can’t visit us

[gewuerzgurkeev]

Great loop, great minds, great discussion

[edizzle]

You're constantly in the present heading towards the future. The past consist of memories only. Time travel will never will be possible.

[blazeharris]

Thumbs up for the loop, nice touch👍🏿😂

[TrendElement]

Oh, so the point is the direction you want to travel in for the destination to be the past, but how do you determine that destination with a path? As I am standing, I can go on upper levels or underground left, right and mostly all directions eventually but what direction does leave to the past?

[brianbarber]

So, if we could go back in time, either time as we know it already “contains” the activities of the time travelers, or they will alter the timeline.

If it contains it, you can’t change anything. It’s also thermodynamically crazy.

If you can change things, eventually, you’d change something that prevents the development of time travel, whether or not it’s theoretically possible, and then it wouldn’t ever happen.

[Tonyrg]

Realistically, traveling backwards in time would just mean deaging yourself, rather than forcing the rest of the universe to go backwards in time.

[mightymite]

Maybe we have met someone from the future !!! 💯

[tarjwilkinson]

If we did travel back in time, wouldn't that make a separate timeline