Is the PAST determined?

[Daemon Sophic]

One other thing. Science is based upon hypothesizing methods for how something that we observe has happened.

You are hypothesizing how time flows.

Tell you what.
You show us a single verifiable incidence when time flowed backward......and humanity will gladly launch several university’s worth of physicists into researching that puppy.
And you can write the proposal!!

 

[shunyadragon]

The only time arrow (expansion, coordinate, entropy) that seems relevant is the entropy arrow and it is far from clear why that should fix the past.

The entropy tim arrow is sufficient to conclude that the past cannot be changed.

 

[Polymath257]

The entropy tim arrow is sufficient to conclude that the past cannot be changed.

Really? Care to give details on how that is derived?

 

[shunyadragon]

Really? Care to give details on how that is derived?

Basic physics, there is absolutely no evidence of a time arrow going back in time regardless of entropy.

There is a problem with time travel the key to the possibility of changing the past.This reference describes some of the problems with changing the past. This is the introduction.

From: Time Travel (Stanford Encyclopedia of Philosophy)
Time Travel
First published Thu Nov 14, 2013; substantive revision Fri Mar 23, 2018
There is an extensive literature on time travel in both philosophy and physics. Part of the great interest of the topic stems from the fact that reasons have been given both for thinking that time travel is physically possible—and for thinking that it is logically impossible! This entry deals primarily with philosophical issues; issues related to the physics of time travel are covered in the separate entries on time travel and modern physics and time machines. We begin with the definitional question: what is time travel? We then turn to the major objection to the possibility of backwards time travel: the Grandfather paradox. Next, issues concerning causation are discussed—and then, issues in the metaphysics of time and change. We end with a discussion of the question why, if backwards time travel will ever occur, we have not been visited by time travellers from the future.

 

[Polymath257]

Basic physics, there is absolutely no evidence of a time arrow going back in time regardless of entropy.

And that isn't required for the past to be undetermined. I said NOTHING at all about a time arrow.

But, for example, is it possible that for some past events, there are two equally valid possibilities? I'm not asking to change the past. I am asking if the past is simply undetermined.

 

[Enoch07]

In other words, is the past fixed once we pass it?

For humans yes.

I don't believe it is. I believe that what we call time is more complex and not linear as we see it.

I see time not as a 2d line that flows in only 1 direction but as a 3d blanket that can flow in any and all directions at once. Of course we cannot experience it in this way, but that is how God experiences time imo.

 

[shunyadragon]

Antical that isn't required for the past to be undetermined. I said NOTHING at all about a time arrow.

But, for example, is it possible that for some past events, there are two equally valid possibilities? I'm not asking to change the past. I am asking if the past is simply undetermined.

For all practical consideration this cannot be determined, except in science fiction,.

Again . . .
From: Time Travel (Stanford Encyclopedia of Philosophy)
Time Travel
First published Thu Nov 14, 2013; substantive revision Fri Mar 23, 2018
There is an extensive literature on time travel in both philosophy and physics. Part of the great interest of the topic stems from the fact that reasons have been given both for thinking that time travel is physically possible—and for thinking that it is logically impossible! This entry deals primarily with philosophical issues; issues related to the physics of time travel are covered in the separate entries on time travel and modern physics and time machines. We begin with the definitional question: what is time travel? We then turn to the major objection to the possibility of backwards time travel: the Grandfather paradox. Next, issues concerning causation are discussed—and then, issues in the metaphysics of time and change. We end with a discussion of the question why, if backwards time travel will ever occur, we have not been visited by time travellers from the future.

 

[MonkeyFire]

You can know the future by veering into the past.

 

[Goodman John]

. . . because the time arrow is only known to go in one direction into the future.

This one time I was on a cruise on the Ship of Theseus; I was trying to shave with Occam's Razor but I took Zeno's Arrow to the knee...

 

[viole]

Basic physics, there is absolutely no evidence of a time arrow going back in time regardless of entropy.

There is a problem with time travel the key to the possibility of changing the past.This reference describes some of the problems with changing the past. This is the introduction.

From: Time Travel (Stanford Encyclopedia of Philosophy)
Time Travel
First published Thu Nov 14, 2013; substantive revision Fri Mar 23, 2018
There is an extensive literature on time travel in both philosophy and physics. Part of the great interest of the topic stems from the fact that reasons have been given both for thinking that time travel is physically possible—and for thinking that it is logically impossible! This entry deals primarily with philosophical issues; issues related to the physics of time travel are covered in the separate entries on time travel and modern physics and time machines. We begin with the definitional question: what is time travel? We then turn to the major objection to the possibility of backwards time travel: the Grandfather paradox. Next, issues concerning causation are discussed—and then, issues in the metaphysics of time and change. We end with a discussion of the question why, if backwards time travel will ever occur, we have not been visited by time travellers from the future.

I think to say that the time arrow is going in the same direction of entropy increase is tautological. It is entropy increase that determines the time arrow.

So, to say that time goes always in the direction of entropy, is like saying that bachelors are not married. And you need no evidence of the contrary. Like you need no evidence for married bachelors.

Ciao

- viole

 

[shunyadragon]

I think to say that the time arrow is going in the same direction of entropy increase is tautological. It is entropy increase that determines the time arrow.

So, to say that time goes always in the direction of entropy, is like saying that bachelors are not married. And you need no evidence of the contrary. Like you need no evidence for married bachelors.

Ciao

- viole

Disagree on picky wording, but agree in substance.