Thread: Practical time travel

Looking at the night sky or old photographs will reveal the past.
But is building a time machine still a possibility to see the future?
The Time Machine by H.G Wells suggests what future engineering might still do.
Unless we can solve the enigma of time we have little or no idea other than unlikely finding a wormhole or black hole.

Entropy is time. Relativity is time.
Even the quantum could decide what is past, present and future. Time's arrow is supposed to go forward and back.

Until resolved we have a few guides to help:
How to Build a Time Machine by Paul Davies.
The Black Hole Survival Guide by Janna Levin.
So You Created a Wormhole (the time travellers guide) by Phil Hornshaw describes what to take.

https://www.youtube.com/watch?v=e-Lj8Scbm3o

All very useful I'm sure.

Could a supercomputer reveal the future by tracking every particle in the universe?

Originally Posted by ox

Even the quantum could decide what is past, present and future. Time's arrow is supposed to go forward and back.

I can’t see the future but I don’t think I’ve ever experienced the present. By the time my brain gets the signal for anything sensed, it’s already in the past. It would be cool if by some chance, that what I sense is actually a future moment albeit nanoseconds, about the only way I figure we can experience the present.

Good point that we don't know how long NOW lasts for, unless it's the coming together of past and future as suggested by the quantum.
In which case NOW cannot be described by our gross senses and understanding of time.

This book suggestts that Francis Everitt at Stanford University is trying to use frame-dragging.

https://www.amazon.co.uk/Time-Travel.../dp/156858363X

https://en.wikipedia.org/wiki/Frame-dragging

Why haven't we seen time travellers from the future?
An answer given by the book is that the first time machine has yet to be switched on.
But would the grandfather paradox prevent an unnatural changing of history?

Originally Posted by ox

Why haven't we seen time travellers from the future?
An answer given by the book is that the first time machine has yet to be switched on.

Perhaps it is because the future has not yet occurred.

If so, there can be no future time machine, only one for the past.

How can a future occur if we are currently living in the present and all our activities have not and cannot produce a future until those events occur?

According to S. Hawking time travel is both possible and impossible.
He tried to welcome time travellers from the future knowing none would arrive, but also implied matter could be recreated.
You would have to have 2 boxes of atoms for the old and new you. Seems unlikely, but be beware they laughed at Einstein.

Ancient astronaut programs suggest the skies are teeming with aliens from a future here on Earth, as well as from distant star systems.
Either they want our DNA or are warning us of the perils of climate change.

For the time being we could refer to Tibetan Buddhism and how to live for 400 years.
We could gaze into the starry sky and contemplate our past lives.

This popped into my head this morning… Since the future is unobserved, is it in a state of superposition, either real or unreal ( there or not there might be better language…idk)?

May not be a superposition but space-time might be more like a curve or loop

https://www.businessinsider.com/phys...15-6?r=US&IR=T

I'm sort of kicking myself at the moment because I recently threw away my only book on practical time travel, and apparently now rare and worth a bit of money.
https://www.goodreads.com/book/show/...al-time-travel

Actually the 2nd worst book I've ever read. The worst was UFO Official Briefing by Anthony Mallin which I still treasure.

If we make contact with aliens we can always ask them about time travel.
I'd also like to ask them about what they think of this book:
https://www.amazon.com/Flying-Saucer.../dp/B06X985YK4
Never even seen it but I'm on the hunt for a copy.

Originally Posted by ox

May not be a superposition but space-time might be more like a curve or loop

https://www.businessinsider.com/phys...15-6?r=US&IR=T

I'm sort of kicking myself at the moment because I recently threw away my only book on practical time travel, and apparently now rare and worth a bit of money.
https://www.goodreads.com/book/show/...al-time-travel

Actually the 2nd worst book I've ever read. The worst was UFO Official Briefing by Anthony Mallin which I still treasure.

If we make contact with aliens we can always ask them about time travel.
I'd also like to ask them about what they think of this book:
https://www.amazon.com/Flying-Saucer.../dp/B06X985YK4
Never even seen it but I'm on the hunt for a copy.

Have an antique store close by that’s chock full of old books. Will go there one of these days to look for those books. I once bought a comic book there for 40 bucks, now worth 10x that.

Think it was a Star Wars movie where the pilot of FTL craft said he needed to plot a path thru space in order to avoid hitting something along the way. I would think that impossible and just how much damage would FTL craft sustain if it hits a grain of sand for instance? I figure not best way to zip through time & space.

Of all the particles in the universe, are there two exactly the same age? Considering all the movements of individual particles over billions of years.

Originally Posted by zinjanthropos

Of all the particles in the universe, are there two exactly the same age? Considering all the movements of individual particles over billions of years.

I assume all hydrogen atoms, quarks and leptons would be the same age.

Originally Posted by ox

I assume all hydrogen atoms, quarks and leptons would be the same age.

But we don't know what happens in black holes, or during merging neutron stars.

If they spit out gold and platinum as some predict during mergers, who knows what is going on at the QM level.

Some aspects of these particles may be involved, changing their timelines of appearance?

I picked this article only because of the date. I googled ‘ can a qubit go back in time’ and saw several articles, most positive re quantum particles moving back in time. Not easy however and very complex, unbelievably hard, and for all intents practically impossible to accomplish. Short read.

https://futurism.com/scientists-reverse-time-quantum

If UFOs are manned(?) by time travellers then why are they always thought of as our descendants when they could be aliens traveling from the past? How many years into the future could a person travel if they’re in a ship moving at .99c for 10 yrs of their time?

After a link to a link above, this appeared.
https://futurism.com/objects-black-holes-wormholes

I'll go one bit further and say that in 100 years we could be travelling not only back in time to the Big Bang or forward to the Big Crunch, but to other universes too.

Originally Posted by ox

After a link to a link above, this appeared.
https://futurism.com/objects-black-holes-wormholes

I'll go one bit further and say that in 100 years we could be travelling not only back in time to the Big Bang or forward to the Big Crunch, but to other universes too.

Is there less matter in the universe today then at BB? More? If black holes are disguised wormholes then does the evidence suggest we’re being slowly transferred to another place & time? Recycling effect? Would universe fill a void and start over or mix with another universe?

More armchair musings/queries: What would happen to light if universe wasn’t expanding? Would it hit some kind of boundary and rebound? How would time be affected if it wasn’t expanding? Seems as if universal expansion keeps time moving forward, like time needs the room. Would wormholes be necessary just to keep matter in motion along with time and space having some place to go?

To answer the above, I don't know.
However it is only space that is expanding outside of local groups of galaxies.

An idea I have is that 'wormholes' are everywhere and possibly the brain has them to store memories.
If all of space is quantum entangled then wormholes may be the link between entangled particles.

The theory of parallel worlds could also work off wormholes.
I once read that we are only the average of the sum of copies in nearby parallel worlds.
How did I remember that? A wormhole from my brain goes back to a book by David Deutsch.

But what prevents us from remembering the future?

Originally Posted by ox

But what prevents us from remembering the future?

The theory of parallel worlds could also work off wormholes.

Perhaps its the wormholes. If they work off the link between entangled particles, they may not be able to "read" the future since they may be transient in the here an now.

There are suggestions of "Entanglement Sudden Death", which may be the cause of their preventing the memory of the future.

And what evidence do we have that parallel worlds remain parallel worlds forever, or do they drift apart from each other due to their decreasing entanglement over time?

Seems like the nature of entanglement is where the answers are. But how does one untangle such mysteries? Can anyone truly understand all this if Entanglement Sudden Death is operative.

Sounds like a real can of entangled wormholes, ox. Perhaps your brain's wormholes can sort it all out! Let's hope so.

If I took the least massive particle known to science and accelerated it as close to c as possible there will always be that little difference between it and a photon. I imagine the time difference between both, to travel anywhere, would be as fleeting as the present seems to us. Could the present be something like that?

Out of curiosity….
https://www.nagwa.com/en/videos/3091...0the%20photon.

Long been a fan of Tibetan thought.
The idea that everything is illusion now has its science equivalent in nothing actually exists.
Could it be that only the undetactable exists such as strings and wormholes?
Might we explain consciousness by these?

The Tibetan idea is based upon the so called chakras, but with a further refinement that they are more like vortices.
A chakra is like the energy inflow or outflow of the vortex.
Ideas that may have come from living at extremes of altitude and cold. Heat yoga is one practice.
Forget the bit about 7 chakras. There are any number.
Similar belief also found in Tai Chi in a practice called condensing.

However, the laws of thermodynamics win in the end.

https://perception.inner-growth.org/...gi-meditation/

Originally Posted by ox

Long been a fan of Tibetan thought.
The idea that everything is illusion now has its science equivalent in nothing actually exists.
Could it be that only the undetactable exists such as strings and wormholes?
Might we explain consciousness by these?

The Tibetan idea is based upon the so called chakras, but with a further refinement that they are more like vortices.
A chakra is like the energy inflow or outflow of the vortex.
Ideas that may have come from living at extremes of altitude and cold. Heat yoga is one practice.
Forget the bit about 7 chakras. There are any number.
Similar belief also found in Tai Chi in a practice called condensing.

However, the laws of thermodynamics win in the end.

https://perception.inner-growth.org/...gi-meditation/

I’ve heard that one before or something similar like our consciousness is the only thing that’s real in a simulated universe. Real good tech if that’s the case. Ever figured out if your consciousness is inside your simulated head or resides outside the simulated body? Where did it come from, like all existence queries, is the next question I guess. Even if they’ve slid through wormhole after wormhole, consciousnesses don’t just pop into existence, do they?

How did wormholes pop into existence?
Aren't we already time travellers, just by having consciousness?

Then I read this one: https://www.theguardian.com/science/...-book-is-wrong
On the Origin of Time is a newly published book I'll put on my reading list.

Originally Posted by ox

Aren't we already time travellers, just by having consciousness?

We live in a time "format " initially derived by humans to organize our lives and project future events, like planting time, etc.

It evolved from sundials to atomic clocks. How do we know that the time we invented is the true time of the universe?

Is it possible that there are variations of time we are not even aware of? All of "time" is as seen through the human experience. What proof is there that we have it right?

When "Hawking announced: “I have changed my mind. My book, A Brief History of Time, is written from the wrong perspective”", how are we to know what the correct perspective is? It is still based on human interpretation.

You pose yet another mind-numbing conundrum. Let's hope you will report back on some solid interpretations of human's definition of time.

Originally Posted by Double Helix

We live in a time "format " initially derived by humans to organize our lives and project future events, like planting time, etc.

This planet keeps turning and turning and taking us with it in free fall at a speed of about 60,000 miles per hour.
Earth's orbit of sun is done in 365 and a bit days and covers 540 million miles.
This is why we have to organise our lives, like when to plant crops.
It's further complicated by the moon, in which some animals appear to base their experience of time.

It evolved from sundials to atomic clocks. How do we know that the time we invented is the true time of the universe?

Depends upon the heat density of location.

Is it possible that there are variations of time we are not even aware of? All of "time" is as seen through the human experience. What proof is there that we have it right?

The word time is just a metaphor for different physical laws.
Everything in language is also metaphor.

When "Hawking announced: “I have changed my mind. My book, A Brief History of Time, is written from the wrong perspective”", how are we to know what the correct perspective is? It is still based on human interpretation.

I'll see what Herzog says in his book.

You pose yet another mind-numbing conundrum. Let's hope you will report back on some solid interpretations of human's definition of time.

Through the generations people have wondered if time exists at all.
The younger you are the longer it seems to last. The older you are the shorter it seems to last.
This might have something to do with how familiar we are with the landscapes around us.
Commenting on relativity Einstein said that enjoying yourself would make time go quicker.
We exist in like a moving spotlight, carrying us from the darkness of the past to the darkness of the future.
We all came out of the darkness and one day we are certain to return to it.

Originally Posted by ox

We all came out of the darkness and one day we are certain to return to it.

We being what we are made of. But during our "lives", we exist in both light and dark. As to the darkness, we are only "waiting for the worms to come." (Roger Waters, The Wall)

It would seem that until the big chill of heat death, which 'we are certain to return to', time to a sentient being would be defined by the changes which occur in our surroundings, like the seasons. But this is only based on the human perspective.

The whole issue of a time "perspective" to any such beings may be highly variable. One can only wonder how aliens interpret such perspectives, and how they might vary throughout the universe. In the Local Group, we are in a micro-backwater of the universe - hardly a true measure of the entire universe, regardless of what our telescopes etc. tell us. It could all be biased. Is it within our capability to even define what the correct perspective is, assuming it even exists?

Seems unlikely we will ever know. We will be eternally compromised by our inherent time-frame lock and location in the cosmos.

Looks like a tough nut to crack.

Originally Posted by Double Helix

We will be eternally compromised by our inherent time-frame lock and location in the cosmos.

Might depend on parallel worlds.
A copy of you could potentially go back in time to kill a copy of your grandfather and overturn the grandfather paradox.
However the probability is very small.

Next time I'm in Liverpool, I'll check this out.
https://medium.com/@NellRose1/the-li...t-7a42898c124b

Is it possible that time does not always flow in straight lines but gets recycled?

Originally Posted by ox

Is it possible that time does not always flow in straight lines but gets recycled?

It seems with parallel worlds, anything is possible. Anti-time may play a role in all of this. May depend on your time perspective.

And then we cannot rule out aliens. Highly advanced forms might be able to accomplish anything, including time manipulation.

More than a few believe we are being invaded and they are messing with us :


"Alien motherships: Pentagon official floats a theory for unexplained sightings"

* https://www.politico.com/news/2023/04/14/pentagon-ufo-alien-object-00092108

If universal expansion >c then is space expanding into the past? If time needs more space for every second that passes, would the universe need to expand to accommodate? Could time be driving expansion?

I understand 'dark energy' is driving the expansion. Time is not energy.
The biggest problem to time travel is that time might not exist at all.
One person who promotes this idea is Julian Barbour who lives on a farm not far from me.

https://en.wikipedia.org/wiki/Julian_Barbour

I have a copy of his book The End of Time, and I'm about to read his recently published The Janus Point.
According to Barbour, not only time but also motion do not exist.
His cat Lucy (before she got killed by a car) could jump up and catch swifts out of the air.
Barbour believes there were infinite copies of her in parallel worlds.
Gosh. To think there are infinite copies of Donald Trump.

But, if aliens visit our solar system they must know how to time travel.

https://howtoacademy.com/events/the-...-our-universe/

Like the Mask of Janus, time travels in 2 directions.
Isn't that a contradiction if time doesn't exist at all?

Originally Posted by ox

But, if aliens visit our solar system they must know how to time travel.

The most significant aspect of the report from those Pentagon observations related to aliens is the nature of some UFOs "which appear to defy all physics".

That suggests that they may have found a way to control space-time.

This would explain why these objects appear to defy physics. By controlling space-time, they can do just about anything.

If you want an answer for practical time travel, you might have to chat with those folks in those spacecraft from another world, assuming they are willing to talk to us.

If it is in preparation of an invasion, that is highly unlikely.

So how do we deal with aliens who can control time travel, and can change "history" to their satisfaction simply by re-running events until they find the acceptable end result?

Originally Posted by Double Helix

So how do we deal with aliens who can control time travel, and can change "history" to their satisfaction simply by re-running events until they find the acceptable end result?

We can talk to them about cosmic strings.
Star Trek revealed they all speak English, so no problem there.

https://www.express.co.uk/news/scien...lbert-einstein

Perhaps they would like something in return. Let's offer them Donald Trump.

Did Nostradamus do some time travelling?
Here's what he is claimed to have said about 2023 in 1555.

https://www.history.co.uk/articles/n...store-for-2023

Ukraine war, climate change, cost of living crisis, Elon Musk are all present.

Originally Posted by ox

Did Nostradamus do some time travelling?

He was either abducted or an alien himself, and indeed appears to have been messing with time.

We can only wonder who else is messing around with it. Wait until ultra-AI kicks in. It will likely change our reality so much that even time travel will become possible.

Originally Posted by Double Helix

Wait until ultra-AI kicks in. It will likely change our reality so much that even time travel will become possible.

A day when you go to your quantum computer and it’s missing but in a few days it’s mysteriously reappeared with a dragonfly the size of a crow perched on it.

One day we could all sign up for a trip to ancient Rome or visit our cyborg future.
But not in this universe.
To think they laughed at Copernicus!

It is unlikely there will ever be an actual time machine where the early versions hit a snag. You could end up trapped at your destination. Later versions might not work too well either.
Think not of a machine but a pathway or place. What David Deutsch advises.

Nostradamus and other seers might have discovered a portal using what has been called a silver thread which links to a parallel world.
While more rational people will junk this idea, his writings are at least half true.
He predicted Hitler, or Hister. A name for the Danube maybe, yet Hitler was Austrian.

But aren't we all time machines of a sort?
We can visit libraries of history books, we can predict a future. Other animals can't.
Once we accept we are living in a multiverse (a set of parallel worlds) we might find a way to explore them.

But there’s a good chance that the multiverse doesn’t exist. Here is a thread of mine explaining it.

A decently common theory is the idea that there are an infinite number of universes, in something called the multiverse. This implies that there is a universe for everything. If this statement is true, then that would mean that another universe managed to invade our universe at this very second, because an infinite number of universes means an infinite number of possibilities. If said theory is true, then there should be an infinite amount of universes invading our universe at this very second. Because this isn’t happening, this leads to the final conclusion that there isn’t an infinite number of universes, which means that either we’re the sole universe, or that there is a finite number of other universes. I would love to hear your thoughts on this.

I’d argue against this actually, I’d say that time traveling into the future is possible, albeit a decently long process of traveling near speed of light, but that traveling into the past isn’t.

You could never travel to a past or future event because events never happen.
Only way would be quantum.