You find yourself in the cretaceous

[Bomb#20]

... So if both guys calculate what time it is in Andromeda right now, they'll get two different answers. Which one is right?

I'm thinking that's incorrect. The foreshortening only takes place during the time the person in question is rotating towards Andromeda rather than over the entire distance the light traveled. In the end the effect of the rotational velocity on space-time dilation for an orbiting body averages out to zero.

Disclaimer: I'm not a physicist and it's been forty years since I took a physics class; it's good when the guys here who know more physics than me check my work. But...

It sounds like you're treating the amount of foreshortening as a property of the observer. I don't think that's right; it's a property of the observer's frame of reference. The observers themselves are rotating, which means they're accelerating, which means they're continuously leaving one frame of reference and entering another. But from the point of view of any particular frame of reference that one of the observers is temporarily in, the foreshortening is constant.

 

[Loren Pechtel]

... So if both guys calculate what time it is in Andromeda right now, they'll get two different answers. Which one is right?

I'm thinking that's incorrect. The foreshortening only takes place during the time the person in question is rotating towards Andromeda rather than over the entire distance the light traveled. In the end the effect of the rotational velocity on space-time dilation for an orbiting body averages out to zero.

Disclaimer: I'm not a physicist and it's been forty years since I took a physics class; it's good when the guys here who know more physics than me check my work. But...

It sounds like you're treating the amount of foreshortening as a property of the observer. I don't think that's right; it's a property of the observer's frame of reference. The observers themselves are rotating, which means they're accelerating, which means they're continuously leaving one frame of reference and entering another. But from the point of view of any particular frame of reference that one of the observers is temporarily in, the foreshortening is constant.

That's my understanding, also. Admittedly, my last physics class was more than 30 years ago.

 

[Bomb#20]

The claim that the entire past is stored somehow and can be broken into by a human somehow is an extraordinary claim.

What is your evidence?

The required extraordinary evidence has been supplied.

Nonsense.

There is ZERO evidence that some past configuration of the universe exists out there such that a human can somehow go there.

You're conflating two different questions. Yes, there's evidence that past configurations of the universe exist out there. But you're correct that there's no evidence that a human can go there; nobody here has claimed there's evidence that we can go to the past. If somebody got in a starship and headed for Andromeda so fast she could finish the voyage, she would of course still arrive in Andromeda's future, not in Andromeda's past. When I said the past can be broken into, I meant "broken into" in the sense that we can look inside -- I was not claiming we could modify it. As far as the current evidence from Relativity* implies, the past appears to be "read-only".

Likewise, most likely no human will ever be able to go to the center of the sun, but that's no reason to think the center of the sun doesn't exist out there.

(* "Closed timelike curves" show up as a solution to the equations of General Relativity, but that of course doesn't mean any actual configuration of matter ever brought one into existence. Also, Quantum Mechanics is a different matter. There is ambiguous evidence from QM suggesting modification of the past may be possible; that's one of the many questions that depend on different "interpretations" of QM.)

The evidence is the Michelson-Morley experiment

This has nothing to do with the existence or non-existence of 'aether'.

The reason the MM experiment refuted the aether is because it showed light goes at the same speed for everybody. It's light going at the same speed for everybody that's a problem for the single-universe-wide-present hypothesis.

the precession of Mercury

This is not evidence the past exists out there in a manner humans can return to it.

I didn't say we could return to it -- we're headed away from it with no known way to turn around.

But to say the past doesn't exist is to say time is just a single point, and the part of the timeline before the present doesn't really exist. The precession of Mercury shows that Newton's theory of gravity as a force bodies exert on one another doesn't quite work, and Einstein's more advanced theory is needed. But in Einstein's theory, gravity is a manifestation of time being curved in the universe's non-Euclidean geometry. Well, if the past doesn't exist, so time is just a single point, then how the bejesus do you figure a single point can be curved?

You have no evidence to support the claim that every configuration of the universe is stored and can somehow be returned to.

I didn't say they can be returned to; but past configurations appear to be stored. (I know Jokodo says that's not what Relativity implies; but he says "The past exists as part of the space-time continuum.", and I don't understand the distinction he's drawing. To my ear that's just different terminology for saying the past is stored. Maybe he just doesn't like the computer-sciency flavor of the word "stored". He can clarify if he wants.)

Of course showing that the universe needs to store at least a few hours of Andromeda's past in order to make sense of our observations doesn't imply every configuration of the universe is stored. But the same argument I made about the rotation of the Earth and a galaxy within the Local Group can be repeated with two observers on two planets on opposite sides of the Milky Way, observing in their gravity-wave detectors the same black-hole merger ten billion light years away across most of the observable universe. There's no obvious limit to the scale of the "bumpiness"; and to suppose the past may be stored long enough to accommodate a certain amount of observed bumpiness but is then deleted would be rather like supposing the universe has a boundary somewhere beyond the edge of our light-cone -- it flies in the face of Occam's Razor.

I want you to tell me what time it is in Andromeda right now. How much time has passed in Andromeda between that gamma ray burst and the slice of Andromeda's timeline that you think actually exists, because it isn't in Andromeda's past or in its future?

This is in no way evidence every past configuration of the universe is stored somehow...

You are waving your hands and jumping up and down and claiming that is an argument.

Well then, when why are you refusing to answer the question? Which observer is right about what time it is in Andromeda?

 

[Treedbear]

... So if both guys calculate what time it is in Andromeda right now, they'll get two different answers. Which one is right?

I'm thinking that's incorrect. The foreshortening only takes place during the time the person in question is rotating towards Andromeda rather than over the entire distance the light traveled. In the end the effect of the rotational velocity on space-time dilation for an orbiting body averages out to zero.

Disclaimer: I'm not a physicist and it's been forty years since I took a physics class; it's good when the guys here who know more physics than me check my work. But...

It sounds like you're treating the amount of foreshortening as a property of the observer. I don't think that's right; it's a property of the observer's frame of reference. The observers themselves are rotating, which means they're accelerating, which means they're continuously leaving one frame of reference and entering another. But from the point of view of any particular frame of reference that one of the observers is temporarily in, the foreshortening is constant.

Seems like I'm in the same boat. Haven't taken a physics course in 40 years. That's why I didn't claim you were wrong. It's just that I'd never heard what you'd claimed comparing the difference between the two observers on opposite sides of the Earth and it got me thinking. I'm in agreement that the distance between either observer and the Andromeda galaxy varies depending on whether they are alternately rotating towards or away from it. So you could imagine it as if the light is traveling along a rubber band that alternately expands and contracts and at any moment the light is traversing some portion which is relatively longer or shorter. Over the entire distance it averages out to the nominal distance experienced by both of the observers.

But that's an interesting paradox. Especially now that you've used the context of the observer's point of view as a property of the observer's (inertial) frame of reference. It comes very close to clarifying for me what Einstein meant when he said "The distinction between the past, present and future is only a stubbornly persistent illusion." I see a common connection between that idea and the idea that there might exist relativistic reference frames as things having distinct and independent existence, above and beyond the momentary relationship that exists between them. You seem to be suggesting that it is something that can be entered and exited and has a continuity independent of the observer. In fact I think you're explicitly stating that. That's very interesting given all the rest of the discussion in this thread about time travel and the concept of block time (or block space-time). It's not something I believe in. To me the past doesn't exist in any real sense. And the future can only be entered one moment at a time. Going "back to the past" would by definition no longer be the past as it once existed by virtue of one's presence there, so it would still be the future (hypothetically speaking). Or more properly the now. I think what Einstein's relativity points out is that while the relative rate of the passage of time between two objects is related to their relative velocities, which one is faster or slower is only resolved and becomes a reality when they meet in the present. But now I can see how from your proposed perspective it would seem as possible that any point in time maintains an existence independent of our relationship to it.

 

[Jokodo]

I know Jokodo says that's not what Relativity implies; but he says "The past exists as part of the space-time continuum.", and I don't understand the distinction he's drawing. To my ear that's just different terminology for saying the past is stored. Maybe he just doesn't like the computer-sciency flavor of the word "stored". He can clarify if he wants.

Well, saying that the past is "stored" the way I believe untermensche intends it (as distinct from the present, which just is), sounds, to stick with the computer metaphor, like the present is the only thing that's in working memory, while the past may or may not have been saved to a backup drive. Not only is this a nonsensical claim when the past and present aren't categorically distinct - "the present" is just a particular slice of reality, of spacetime, that is accessible to an observer within their reference frame. More importantly, it gives weight to untermensche's objection: If the past is not part of this reality but only exists, at best, on some backup tape in God's attic, then obviously the question arises who or what would bother to restore that backup when someone wants to peek into the past.

We don't generally say something is "stored" when something exists as part of this reality but isn't easily accessible: We don't say the sun is stored in the sky above Ethiopia when it's night on the West Coast, and gets restored into the sky above the western Atlantic Ocean in your morning, to be transferred into the sky above the eastern Pacific for your noon. It's every bit as real throughout the day, and that you can't see it (or where you see it when you do) is on you and your particular position.

When I read untermensche discussing whether it makes sense to assume the past is stored, it sounds to me like he's falling victim to a two-way confusion between the map and the countryside: Not only does he confuse "the present" (i.e., a particular view of spacetime from within a particular reference frame) for the only real thing, but he also confuses the majority of reality for a representation of something that doesn't exist. He's saying that in order for someone to travel to the past, there'd have to be an atlas with a map of the universe at every past instant, and someone would have to find the right map and a build a new real universe from it. Of course that would be nonsensical, but it takes confusing the map for the countryside and the countryside for an atlas that may or may not exist for this objection to make sense.

 

[untermensche]

The universe is undergoing change. Whatever the universe is it is active and changing.

The past is the exact same universe with all the same matter and energy but it was arranged differently within a different space.

The vase falls and breaks. It does not matter the "now" of the observer. No observer can make the broken vase unbroken.

To go back in time is to make all broken vases unbroken. It is to make the dead undead.

If an observer is going to leave the configuration of the universe they exist within and return to some prior configuration then that prior configuration must be stored somehow. Every little bit of quantum information must be stored.

But not only stored but continually recording and rerecording.

Because if one observer goes back in time they are now part of a new recording that is stored.

And there is no way to change the past without changing the present.

An observer going to the past changes the past the present and the future.

How does all the unique information existing in the past still exist unless it was stored?

Going to the past is easy.

We just need to aim towards the stored past and move towards it.

 

[Jokodo]

The universe is undergoing change. Whatever the universe is it is active and changing.

The past is the exact same universe with all the same matter and energy but it was arranged differently within a different space.

The vase falls and breaks. It does not matter the "now" of the observer. No observer can make the broken vase unbroken.

To go back in time is to make all broken vases unbroken. It is to make the dead undead.

If an observer is going to leave the configuration of the universe they exist within and return to some prior configuration then that prior configuration must be stored somehow. Every little bit of quantum information must be stored.

But not only stored but continually recording and rerecording.

Because if one observer goes back in time they are now part of a new recording that is stored.

And there is no way to change the past without changing the present.

An observer going to the past changes the past the present and the future.

How does all the unique information existing in the past still exist unless it was stored?

Going to the past is easy.

We just need to aim towards the stored past and move towards it.

I prefer my tea and coffee conversations with data and experimental results that confirm your hypotheses. I get stomach ache from unfounded ad hoc declarations.

 

[Jokodo]

The universe is undergoing change. Whatever the universe is it is active and changing.

The past is the exact same universe with all the same matter and energy but it was arranged differently within a different space.

Not really, no. Matter and energy get created and destroyed literally all the time. What you may want to say is that the past universe has the same net mass/energy. Quite possibly, that sum, the net mass/energy of the universe past present and future, is actually 0.

The vase falls and breaks. It does not matter the "now" of the observer. No observer can make the broken vase unbroken.

To go back in time is to make all broken vases unbroken. It is to make the dead undead.

Not in any meaningful sense, no.

If an observer is going to leave the configuration of the universe they exist within and return to some prior configuration then that prior configuration must be stored somehow. Every little bit of quantum information must be stored.

Not in any meaningful sense of "be stored" as distinct from "exist". If you go on a round-the-world trip once intercontinental travel is once again as easy as it used to be, do you also say that North America "must be stored" in order for it to still be there when you've done your thing in Asia and Europe?

But not only stored but continually recording and rerecording.

Only if you mistake the map for the countryside, and the countryside for a map.

Because if one observer goes back in time they are now part of a new recording that is stored.

Or in simpler terms, they're part of this universe, only located at a different coordinate set.

And there is no way to change the past without changing the present.

An observer going to the past changes the past the present and the future.

Maybe so. Maybe not. That's nothing to do with whether and in what sense the universe has to be "stored".

How does all the unique information existing in the past still exist unless it was stored?

How does the sun still exist when it's night unless it was stored? The past never ceases to be part of reality, it only is inaccessible from a particular reference frame.

Going to the past is easy.

We just need to aim towards the stored past and move towards it.

You know what? I think that it is probably practically impossible to move macroscopic objects arbitrarily in time. The past is, if I have to guess, more likely than not one of those places we'll never be able to reach. There is a lot of those places - in some cases, the trip is impossible, in others, the trip is possible as such but not survivable, and in yet others, while the trip is survivable in principle, the destination if immediately lethal. You have to have a very, absurdly, anthropocentric worldview though to conclude that that which no human will ever reach therefore doesn't exist - or do you believe the interior of the Sun and Earth do not exist?

 

[skepticalbip]

This seems to be similar to the case of Galileo trying to convince the church that the Sun was the center of the solar system. The church couldn't accept the idea of a heliocentric solar system and untermenche can't, or won't, accept the idea of a spacetime universe.

 

[Treedbear]

Nonsense.

There is ZERO evidence that some past configuration of the universe exists out there such that a human can somehow go there.

... Yes, there's evidence that past configurations of the universe exist out there. ... When I said the past can be broken into, I meant "broken into" in the sense that we can look inside -- I was not claiming we could modify it. As far as the current evidence from Relativity* implies, the past appears to be "read-only".

What do you mean by look inside the past? If you mean to look at Andromeda is to see it as it was 2.5 million years ago that's no different than watching reruns of MASH. It's a record of the past as it exists in the present.

...
But to say the past doesn't exist is to say time is just a single point, and the part of the timeline before the present doesn't really exist. The precession of Mercury shows that Newton's theory of gravity as a force bodies exert on one another doesn't quite work, and Einstein's more advanced theory is needed. But in Einstein's theory, gravity is a manifestation of time being curved in the universe's non-Euclidean geometry. Well, if the past doesn't exist, so time is just a single point, then how the bejesus do you figure a single point can be curved?

Relativity is a mathematical representation of reality. Its equations can be rendered graphically. At each point on that graph you can calculate a tangent and a slope. Space-time is thus said to be curved with a particular rate of change associated with each point. And the curve differs depending on the perspective of the observer. (I think that's about right.)

You have no evidence to support the claim that every configuration of the universe is stored and can somehow be returned to.

I didn't say they can be returned to; but past configurations appear to be stored. ...

Of course showing that the universe needs to store at least a few hours of Andromeda's past in order to make sense of our observations doesn't imply every configuration of the universe is stored. But the same argument I made about the rotation of the Earth and a galaxy within the Local Group can be repeated with two observers on two planets on opposite sides of the Milky Way, observing in their gravity-wave detectors the same black-hole merger ten billion light years away across most of the observable universe. There's no obvious limit to the scale of the "bumpiness"; and to suppose the past may be stored long enough to accommodate a certain amount of observed bumpiness but is then deleted would be rather like supposing the universe has a boundary somewhere beyond the edge of our light-cone -- it flies in the face of Occam's Razor.

What observations are you citing?

I want you to tell me what time it is in Andromeda right now. How much time has passed in Andromeda between that gamma ray burst and the slice of Andromeda's timeline that you think actually exists, because it isn't in Andromeda's past or in its future? ...

I believe that can be calculated using the equations of special and general relativity whether you are on one side of the Earth or the other. The results will be the same when the conditions of the observers are taken into account.

 

[untermensche]

The universe is undergoing change. Whatever the universe is it is active and changing.

The past is the exact same universe with all the same matter and energy but it was arranged differently within a different space.

The vase falls and breaks. It does not matter the "now" of the observer. No observer can make the broken vase unbroken.

To go back in time is to make all broken vases unbroken. It is to make the dead undead.

If an observer is going to leave the configuration of the universe they exist within and return to some prior configuration then that prior configuration must be stored somehow. Every little bit of quantum information must be stored.

But not only stored but continually recording and rerecording.

Because if one observer goes back in time they are now part of a new recording that is stored.

And there is no way to change the past without changing the present.

An observer going to the past changes the past the present and the future.

How does all the unique information existing in the past still exist unless it was stored?

Going to the past is easy.

We just need to aim towards the stored past and move towards it.

I prefer my tea and coffee conversations with data and experimental results that confirm your hypotheses. I get stomach ache from unfounded ad hoc declarations.

The whole idea of time travel is a thought experiment with no data or even hypothesis. You must give yourself a lot of stomach aches.

 

[Jokodo]

The universe is undergoing change. Whatever the universe is it is active and changing.

The past is the exact same universe with all the same matter and energy but it was arranged differently within a different space.

The vase falls and breaks. It does not matter the "now" of the observer. No observer can make the broken vase unbroken.

To go back in time is to make all broken vases unbroken. It is to make the dead undead.

If an observer is going to leave the configuration of the universe they exist within and return to some prior configuration then that prior configuration must be stored somehow. Every little bit of quantum information must be stored.

But not only stored but continually recording and rerecording.

Because if one observer goes back in time they are now part of a new recording that is stored.

And there is no way to change the past without changing the present.

An observer going to the past changes the past the present and the future.

How does all the unique information existing in the past still exist unless it was stored?

Going to the past is easy.

We just need to aim towards the stored past and move towards it.

I prefer my tea and coffee conversations with data and experimental results that confirm your hypotheses. I get stomach ache from unfounded ad hoc declarations.

The whole idea of time travel is a thought experiment with no data or even hypothesis. You must give yourself a lot of stomach aches.

"If it is possible, what could it look like?" is not a declaration - it's a question. "It can't be possible because <misunderstood/outdated physics> and <incoherent pseodophilosophy>" is a declaration.

I thought English was your native language? Why am I teaching you word meanings?

 

[untermensche]

Not really, no. Matter and energy get created and destroyed literally all the time. What you may want to say is that the past universe has the same net mass/energy. Quite possibly, that sum, the net mass/energy of the universe past present and future, is actually 0.

Matter and energy are the same thing in two different forms.

And matter is never destroyed. It might change to it's other form.

Not in any meaningful sense, no.

Go back to a time when the vase is intact you have somehow made a broken vase unbroken. You have made all the people who died after the vase broke come back to life. Spooky magic.

A miracle one might say.

Not in any meaningful sense of "be stored" as distinct from "exist".

If it exists somehow it must be stored somehow.

Abraham Lincoln was shot in the head and is dead.

If he is also still living in 1862 such that a person could go back and talk with him then every single bit of quantum information that made up Lincoln's life is stored somehow.

You can't go visit a dead man unless their entire existence is stored somehow.

Eternally.

What silly hogwash.

Or in simpler terms, they're part of this universe, only located at a different coordinate set.

Nope. They have a genetic code that did not exist at that time.

They somehow broke into a complete universe that did not have their genetic code.

They completely changed that universe.

In the time of the dinosaurs there were no humans. If one suddenly appears that means the entire universe has been changed.

Only if you mistake the map for the countryside, and the countryside for a map

Gibberish.

How does the sun still exist when it's night unless it was stored?

More gibberish.

If you can observe the sun then the energy from the sun is existing as you observe it.

Things that exist such that they can be observed do not pop in and out of existence like some deluded clown going through time.

The past never ceases to be part of reality, it only is inaccessible from a particular reference frame.

This is a religious belief that has no evidence to support it.

 

[Bomb#20]

...
We don't generally say something is "stored" when something exists as part of this reality but isn't easily accessible: We don't say the sun is stored in the sky above Ethiopia when it's night on the West Coast,...

I feel a metaphor coming on....

The Seventh Sally or How Trurl's Own Perfection Led to No Good*

"Don't you see, when the imitator is perfect, so must be the imitation, and the semblance becomes the truth, the pretense a reality!"

(* From The Cyberiad, by Stanislaw Lem)

 

[Jokodo]

Matter and energy are the same thing in two different forms.

And matter is never destroyed. It might change to it's other form.



Go back to a time when the vase is intact you have somehow made a broken vase unbroken.

No, you haven't. You have visited a time and place where/when it always was unbroken (unless it has been mended before, of course). You don't "make the Sun rise" by flying to an timezone, or do you?

You have made all the people who died after the vase broke come back to life. Spooky magic.

A miracle one might say.

Not in any meaningful sense of "be stored" as distinct from "exist".

If it exists somehow it must be stored somehow.

Are you stored? Do you exist? If you answer "yes" to both questions, I'll need you to define "stored", as you clearly aren't using it the way I understand it. If you answer no to the first, your very existence disproved your claim.

Abraham Lincoln was shot in the head and is dead.

If he is also still living in 1862 such that a person could go back and talk with him then every single bit of quantum information that made up Lincoln's life is stored somehow.

That doesn't follow, at least not without a neckbreaking redefinition of "stored".

You can't go visit a dead man unless their entire existence is stored somehow.

Eternally.

What silly hogwash.

Or in simpler terms, they're part of this universe, only located at a different coordinate set.

Nope. They have a genetic code that did not exist at that time.

They somehow broke into a complete universe that did not have their genetic code.

They completely changed that universe.

They did not. They visited a time and place with a different postion on the t axis in one and the same four (or more) dimensional universe.

In the time of the dinosaurs there were no humans. If one suddenly appears that means the entire universe has been changed.

Only if you mistake the map for the countryside, and the countryside for a map

Gibberish.

How does the sun still exist when it's night unless it was stored?

More gibberish.

If you can observe the sun then the energy from the sun is existing as you observe it.

And when it's night, you can't observe it. That's exactly why I am asking. Why do you believe the sun continues to exist on a moonless night?

Things that exist such that they can be observed do not pop in and out of existence like some deluded clown going through time.

The sun cannot be observed at night.

The past never ceases to be part of reality, it only is inaccessible from a particular reference frame.

This is a religious belief that has no evidence to support it.

It has a lot more evidence to it than anything you've written in this thread.

 

[untermensche]

No, you haven't. You have visited a time and place where/when it always was unbroken (unless it has been mended before, of course). You don't "make the Sun rise" by flying to an timezone, or do you?

At least we are done with that "matter is destroyed all the time" nonsense.

There is no moment in time where the vase is unbroken forever. The vase was not unbroken forever so no such moment in time can exist. You are talking about an irrational fantasy.

There are moments in time before it was constructed. Moments in time when it was unbroken then an eternity when it was broken.

You are talking about going from some moment when the vase was broken to a moment when it was unbroken.

You have somehow reconstructed that vase.

Made the dead come alive.

Congratulations.

That doesn't follow, at least not without a neckbreaking redefinition of "stored".

It is your miracle.

It is up to you to say how a living Lincoln can exist without bringing the dead Lincoln back to life.

Lincoln did have a life and you were not in it.

You cannot return to Lincoln's life.

By returning you have changed the entire universe including Lincoln's life.

You have not returned to Lincoln's life.

You have breathed life into the dead Lincoln and given him an entirely new life.

Like a god.

 

[Jokodo]

No, you haven't. You have visited a time and place where/when it always was unbroken (unless it has been mended before, of course). You don't "make the Sun rise" by flying to an timezone, or do you?

At least we are done with that "matter is destroyed all the time" nonsense.

Maybe you should read up on the  Casimir_effect?

There is no moment in time where the vase is unbroken forever. The vase was not unbroken forever so no such moment in time can exist.

But there are moments in time where it is not yet broken. Like there are places on the planet where the sun has not yet risen above the horizon.

You are talking about an irrational fantasy.

There are moments in time before it was constructed. Moments in time when it was unbroken then an eternity when it was broken.

You are talking about going from some moment when the vase was broken to a moment when it was unbroken.

Exactly. No miracle required.

You have somehow reconstructed that vase.

Only in the same sense in which I have lowered the sun below the Eastern horizon by flying West with a supersonic jet.

Made the dead come alive.

Congratulations.

That doesn't follow, at least not without a neckbreaking redefinition of "stored".

It is your miracle.

It is up to you to say how a living Lincoln can exist without bringing the dead Lincoln back to life.

I'll tell you as soon as you tell me how a sun above the horizon can exist during your night without moving the sun!

 

[Jokodo]

Like a god.

I don't know, I feel it rather takes considering yourself a God to conclude reality ends at the edge of your visual field.

 

[Elixir]

Like a god.

I don't know, I feel it rather takes considering yourself a God to conclude reality ends at the edge of your visual field.

Especially true when the same person makes pronouncements about what goes on in "eternity" while denying the possible existence of "eternity" doe to its infinite nature.

 

[untermensche]

Like a god.

I don't know, I feel it rather takes considering yourself a God to conclude reality ends at the edge of your visual field.

As soon as you show me any observer that can pick up the broken glass whole you have a point.

Reality is not what I can observe.

It is what is possible for any observer to observe.

Reality is that which could possibly be observed or detected in some way.

No observer can go back and observe Lincoln without changing reality.

And no observer of Lincoln exists anymore.