Spacetime, the Universe, the Present and the Future

In summary: I think it would be more plausible to say that the present exists as an objective reality, but that the future is not predetermined and that it is possible for events to happen that we have not yet experienced.In summary, there seems to be a lack of consensus in the field of physics regarding the existence of a 'future predetermined' and whether or not time is only another dimension like space in the static construct of spacetime. Some papers support the idea while others do not. There is some debate and personal interpretation surrounding the issue.
  • #1
Seeker2K
6
0
At http://en.wikipedia.org/wiki/Spacetime#Historical_origin I read the following quote:
In 1895, H.G. Wells in his novel, The Time Machine, wrote, “There is no difference between Time and any of the three dimensions of Space except that our consciousness moves along it.” He added, “Scientific people…know very well that Time is only a kind of Space.”

Wouldn't this imply that the universe (respectively spacetime) is actually static and that the present doesn't really exist except for our consciousness? And wouldn't this also imply that in such a universe the future would also be already determined, if time is only another dimension like space in the static construct of spacetime?

What is the general understanding regarding these issues in the field of physics today? Or is this more or less a matter of debate and/or personal interpretation of spacetime?
 
Physics news on Phys.org
  • #2
Seeker2K said:
At http://en.wikipedia.org/wiki/Spacetime#Historical_origin I read the following quote:


Wouldn't this imply that the universe (respectively spacetime) is actually static and that the present doesn't really exist except for our consciousness? And wouldn't this also imply that in such a universe the future would also be already determined, if time is only another dimension like space in the static construct of spacetime?

What is the general understanding regarding these issues in the field of physics today? Or is this more or less a matter of debate and/or personal interpretation of spacetime?
Since time plays the same role mathematically, but not physically, then there is a sense where one can say that space plays the same role as time but the fact still remains that this relationship is a role mathematically, but not physically. Either way the universe exist. If it didn't then I'd be hard pressed to say who posted this thread. :smile:

Pete
 
  • #3
Seeker2K said:
At http://en.wikipedia.org/wiki/Spacetime#Historical_origin I read the following quote:


Wouldn't this imply that the universe (respectively spacetime) is actually static and that the present doesn't really exist except for our consciousness? And wouldn't this also imply that in such a universe the future would also be already determined, if time is only another dimension like space in the static construct of spacetime?

What is the general understanding regarding these issues in the field of physics today? Or is this more or less a matter of debate and/or personal interpretation of spacetime?


I would say that there is NOT a consensus whether the future is predetermined or not.

There are apparently some enthusiasts at the Wikipedia who have written and believe that there aren't any alternatives.

For some papers that take different views see the references in my post in PF

https://www.physicsforums.com/showpost.php?p=1176689&postcount=6

you may also find the thread of which this is a part of some interest (select view thread).
 
  • #4
Time and space are not completely equivalent

H. G. Wells didn't have it quite right, if you are trying to read that (anachronistically) as a description of Minkowski spacetime. You can turn around in space---your world line can describe a helical arc--- but you can't turn around in time--- your world line can't "turn over" and start heading into the past.
 
  • #5
Chris Hillman said:
H. G. Wells didn't have it quite right, if you are trying to read that (anachronistically) as a description of Minkowski spacetime. You can turn around in space---your world line can describe a helical arc--- but you can't turn around in time--- your world line can't "turn over" and start heading into the past.

besides that (the "arrow of time" vs. some "arrow of space" which i don't think exists outside of the event horizon of black holes), i don't think (from an amateurish read) that they have precisely the same role mathematically (responding to Pete). [itex] t^2 [/itex] has a minus sign attached to it where [itex] x^2, y^2, z^2 [/itex] all have plus signs.
 
  • #6
pervect said:
I would say that there is NOT a consensus whether the future is predetermined or not.

Seems you are right...

For some papers that take different views see the references in my post in PF

https://www.physicsforums.com/showpost.php?p=1176689&postcount=6

you may also find the thread of which this is a part of some interest (select view thread).

Yes, I took a look at the thread and at the papers. Dieks' "Time in special relativity and its philosophical significance" sounds interesting, but unfortunately I can only access the abstract.
The paper by Mauro Dorato is interesting as well, but apparently he is supporting a kind of kantian point of view in which time is something purely mental and only exists in our consciousness. I wonder how objects are supposed to exist then, if time and space only exist in our minds - does spacetime only exist in our minds/consciousness as well then? I have to say that I am no expert regarding Kant though. :wink:
However, according to the author of that paper Kant’s view of time is actually vindicated by relativity.

Personally I have thought about all of these issues and currently think that it could be problematic to combine an objective, universal 'present' with the theory of relativity, as there would be problems with simultaneity. However I think that it should still be possible that there is something like a 'present' with an open future for every existing frame of reference in space. The existence of such a shifting 'present' doesn't directly follow from the concept of spacetime as all points in the time dimension appear to be equal there, but something has to be added to this concept anyway, as there surely is something as an 'experienced present' that moves through time from the past to the future in our consciousness. Everybody can surely say that there is a certain moment in time that he/she is experiencing right now (for him/her at least). The question remains if it only exists in our minds or if there is some general kind of 'flow of time' with a past, present and open future.
 
Last edited:
  • #7
Some might be interested in reading Julian Barbour's views on time. He wrote a book called "The End of Time".

His website is called http://www.platonia.com/index.html" .

" ... time is an illusion.
The phenomena from which
we deduce its existence are real,
but we interpret them wrongly.
My arguments are presented in
The End of Time."

- Julian Barbour.
 
Last edited by a moderator:

1. What is spacetime?

Spacetime is the concept that combines the three dimensions of space (length, width, and height) with the dimension of time. It is a mathematical model that describes the relationship between physical objects in the universe and how they move through space and time.

2. How did the universe begin?

The prevailing theory is that the universe began with the Big Bang, a massive explosion that occurred approximately 13.8 billion years ago. This explosion caused the expansion of matter and energy, leading to the formation of galaxies, stars, and planets.

3. What is the present moment in spacetime?

The present moment in spacetime is a constantly changing point in the four-dimensional model that represents the current state of the universe. It is a relative concept, as the present moment for one observer may be different for another, depending on their position and velocity in space.

4. Will the universe ever end?

There are several theories about the fate of the universe. One possibility is the Big Crunch, where the expansion of the universe will eventually reverse, causing it to collapse in on itself. Another possibility is the Big Freeze, where the universe continues to expand and eventually becomes cold and dark. However, the most current research suggests that the universe will continue to expand indefinitely.

5. Can we travel through time?

According to the theory of relativity, time is relative and can be affected by factors such as gravity and velocity. This means that it is possible to experience time dilation, where time moves slower for an object moving at high speeds. However, physically traveling backwards in time is not currently possible, as it would require breaking the laws of physics.

Similar threads

Block Universe Theory: Implications & Multiverse
    • Special and General Relativity
Replies
6
Views
2K
I Exploring Spacetime Interval at a Singularity: Tad Williams' Otherland
    • Special and General Relativity
Replies
9
Views
776
B Matter & Spacetime: How Tightly Coupled Are They?
    • Special and General Relativity
Replies
16
Views
1K
I Coordinate System for Minkowskian Spacetime Relative to Event
    • Special and General Relativity
Replies
8
Views
892
B Unlearning the Block Universe: How Relativity Challenges Our Perception of Time
    • Special and General Relativity
3
Replies
90
Views
5K
I Spacetime of Flatland: Exploring a 2D Universe
    • Special and General Relativity
Replies
2
Views
1K
B Need to Check GR Beliefs? Integrity Filter Here!
    • Special and General Relativity
Replies
27
Views
1K
B Gravitational Wave System and Locations
    • Special and General Relativity
Replies
2
Views
621
I Why isn't spacetime considered as true 4D?
    • Special and General Relativity
Replies
22
Views
4K
SpaceTime... Why can we access past but not future events
    • Special and General Relativity
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top