Is the block universe just a whole bunch of world lines (from the elementary particles)?

[34student]

If the question in the title is yes, then is velocity and speed just the shape that the "strings" make? 

And if the answer is yes to the second question as well, then what does it physically mean to "be an observer travelling at relativistic speeds"?

Finally, how does length contraction come into all of this if these strings are static and unchanging? 

 

Please help me 

 

[beecee]

12 minutes ago, 34student said:

If the question in the title is yes, then is velocity and speed just the shape that the "strings" make? 

And if the answer is yes to the second question as well, then what does it physically mean to "be an observer travelling at relativistic speeds"?

Finally, how does length contraction come into all of this if these strings are static and unchanging? 

 

Please help me 

 

Firstly string theory and its derivites are still not validated, as beautiful as it may appear.

Secondly we do have verifiable evidence for length contraction, as well as time dilation.

Edited November 24, 2021 by beecee

[studiot]

21 minutes ago, 34student said:

If the question in the title is yes, then is velocity and speed just the shape that the "strings" make? 

And if the answer is yes to the second question as well, then what does it physically mean to "be an observer travelling at relativistic speeds"?

Finally, how does length contraction come into all of this if these strings are static and unchanging? 

 

Please help me 

 

Is this just a repeat of your last thread ?

 

[MigL]

I think he means worldlines when he says 'strings', Beecee.

And apparently he still hasn't done any research into the block universe model, Studiot.

[34student]

8 minutes ago, beecee said:

Firstly string theory and its derivites are still not validated, as beautiful as it may appear.

Secondly we do have verifiable evidence for length contraction, as well as time dilation.

I am talking about the implications of relativity as in the block universe.  Since particles appear to just exist as static world lines, I do not understand how a static universe like this can have different parts that are simultaneously different sizes from length contraction.

And what does it physically mean to be an observer?

[studiot]

4 minutes ago, 34student said:

I am talking about the implications of relativity as in the block universe.  Since particles appear to just exist as static world lines, I do not understand how a static universe like this can have different parts that are simultaneously different sizes from length contraction.

And what does it physically mean to be an observer?

To understand this, you have have to understand what a world line is.

What do you think a world line is ? : You have stated that particles exist as world lines - (static or otherwise whatever that means)  - .

Do this mean that you think world lines are particles  ?

[34student]

6 minutes ago, studiot said:

To understand this, you have have to understand what a world line is.

What do you think a world line is ? : You have stated that particles exist as world lines - (static or otherwise whatever that means)  - .

Do this mean that you think world lines are particles  ?

Yes.  Isn't a particle a world line because of its time dimension?

[studiot]

8 minutes ago, 34student said:

Yes.  Isn't a particle a world line because of its time dimension?

So you are positing that at least some world lines have mass, momentum, kinetic energy, spin and so forth if they are particles ?

Edited November 25, 2021 by studiot

[34student]

2 minutes ago, studiot said:

So you are positing that at least some world lines have mass, momentum, kinetic energy, spin and so forth if they are particles ?

A world line, as exactly defined, is not a particle.  But I understand that the world line is the path that the particle take through the 4 dimensions.  But in another since, the block universe seems to imply that the particle exists along the world line.

[studiot]

1 minute ago, 34student said:

A world line, as exactly defined, is not a particle.  But I understand that the world line is the path that the particle take through the 4 dimensions.  But in another since, the block universe seems to imply that the particle exists along the world line.

But that is not what you said before.

32 minutes ago, 34student said:

Since particles appear to just exist as static world lines

That seems to me to say that a particle is a world line.

 

Please be more careful to state exactly what you mean.

The first and most obvious characteristic of a world line is that it is a line.

That is it is one dimensional.

There is no problem with that, one dimensional 'lines' can exist in any number of dimensions greater than or equal to one.

However being just a line also limits what a world line can represent.

Did I say represent ?

Yes, because the block universe is just a representation (or model) of the 'real' universe we are part of.

It is indeed a four dimensional continuum of points.

Lines are a one dimensional continuum of points that could be the points of our four dimensional block, making as you say a path.

So here is something to think about.

Take an ordinary suspended pendulum - a bob on a string.

Let it swing freely, firstly just side to side, and then round and round in a circle.

What does the world line look like in one, two, three and four dimensions ?

You might be a little suprised.

[34student]

4 minutes ago, studiot said:

But that is not what you said before.

That seems to me to say that a particle is a world line.

 

Please be more careful to state exactly what you mean.

The first and most obvious characteristic of a world line is that it is a line.

That is it is one dimensional.

There is no problem with that, one dimensional 'lines' can exist in any number of dimensions greater than or equal to one.

However being just a line also limits what a world line can represent.

Did I say represent ?

Yes, because the block universe is just a representation (or model) of the 'real' universe we are part of.

It is indeed a four dimensional continuum of points.

Lines are a one dimensional continuum of points that could be the points of our four dimensional block, making as you say a path.

So here is something to think about.

Take an ordinary suspended pendulum - a bob on a string.

Let it swing freely, firstly just side to side, and then round and round in a circle.

What does the world line look like in one, two, three and four dimensions ?

You might be a little suprised.

The side to side motion would look like s's connecting over and over, and the circular motion would look like a spring.

[beecee]

1 hour ago, MigL said:

I think he means worldlines when he says 'strings', Beecee.

And apparently he still hasn't done any research into the block universe model, Studiot.

Thanks for that. Off with me head, on with a pumkin!🥴

 

[MigL]

2 hours ago, 34student said:

And what does it physically mean to be an observer?

Finally a good question ... +1

An observer sees a 'foliation' of the 4 dimensional block.
The observer's FoR determines the orientation of the foliation with respect to the spatial/temporal dimensions.
This orientation will have varying lengths, and durations, for differing observers.

And all foliations are equally valid.

[studiot]

19 hours ago, 34student said:

The side to side motion would look like s's connecting over and over, and the circular motion would look like a spring.

Yeay, pretty good.

Here is something to consider about your question

20 hours ago, 34student said:

what does it physically mean to "be an observer travelling at relativistic speeds"?

The Penrose - Terrell rotation.

 

Perhaps @Markus Hanke or @Janus  might be willing to offer more on this.

The point is that real object occupy a real amount of space (that is they are not points).
So a trace of their passage through the block is not a fine line somewhat smeared out.

 

 

 

 

I am very sorry but the input editor is playing up again and will not let me put the two pages in the correct order.

I would be very grateful to any moderator that can put this right.

Edited November 25, 2021 by studiot

[studiot]

Lots of physical examples of the P_T effect here

https://physicsworld.com/a/the-invisibility-of-length contraction/

[34student]

21 hours ago, MigL said:

Finally a good question ... +1

An observer sees a 'foliation' of the 4 dimensional block.
The observer's FoR determines the orientation of the foliation with respect to the spatial/temporal dimensions.
This orientation will have varying lengths, and durations, for differing observers.

And all foliations are equally valid.

Thanks. 

But this theory makes me think of the universe as one huge physical contradiction.  To a photon the universe is a pancake; to me it is spacious.  Is the universe spacious or is it a pancake?  If both answers are correct, then we have a contradiction.  What am I missing here?  And why isn't this a bigger issue?

 

[beecee]

13 minutes ago, 34student said:

Thanks. 

But this theory makes me think of the universe as one huge physical contradiction.  To a photon the universe is a pancake; to me it is spacious.  Is the universe spacious or is it a pancake?  If both answers are correct, then we have a contradiction.  What am I missing here?  And why isn't this a bigger issue?

 

No, we have relativity.

Why it isn't an issue, is that it is supported by scientific evidence. Problems in individual frames. all have their different equivelent solutions. Other then where acceleration is involved.

Edited November 26, 2021 by beecee

[34student]

15 minutes ago, beecee said:

No, we have relativity.

Why it isn't an issue, is that it is supported by scientific evidence. Problems in individual frames. all have their different equivelent solutions. Other then where acceleration is involved.

This simply says that the universe, in its entirety and ontologically, has intrinsic properties A, B, C ..., but it also does not have intrinsic properties A, B, C....  At best it seems to be a consistent ontological contradiction. 

Edited November 26, 2021 by 34student

[beecee]

26 minutes ago, 34student said:

This simply says that the universe, in its entirety and ontologically, has intrinsic properties A, B, C ..., but it also does not have intrinsic properties A, B, C....  At best it seems to be a consistent ontological contradiction. 

No, it says that space and time are relative, and we make many allowances for that fact. GPS Satellites, muon arrival times, synchronised atomic clocks, particle accelerators.........https://www.scientificamerican.com/article/einsteins-time-dilation-prediction-verified/ 

"Experiments at a particle accelerator have confirmed the "time dilation" effect predicted by Albert Einstein's special theory of relativity"

"Physicists have verified a key prediction of Albert Einstein’s special theory of relativity with unprecedented accuracy. Experiments at a particle accelerator in Germany confirm that time moves slower for a moving clock than for a stationary one.

The work is the most stringent test yet of this ‘time-dilation’ effect, which Einstein predicted. One of the consequences of this effect is that a person travelling in a high-speed rocket would age more slowly than people back on Earth.

Few scientists doubt that Einstein was right. But the mathematics describing the time-dilation effect are “fundamental to all physical theories”, says Thomas Udem, a physicist at the Max Planck Institute for Quantum Optics in Garching, Germany, who was not involved in the research. “It is of utmost importance to verify it with the best possible accuracy.”

The paper was published on September 16 in Physical Review Letters. It is the culmination of 15 years of work by an international group of collaborators including Nobel laureate Theodor Hänsch, director of the Max Planck optics institute"

 

more...............

[34student]

5 minutes ago, beecee said:

No, it says that space and time are relative, and we make many allowances for that fact. GPS Satellites, muon arrival times, synchronised atomic clocks, particle accelerators.........https://www.scientificamerican.com/article/einsteins-time-dilation-prediction-verified/ 

"Experiments at a particle accelerator have confirmed the "time dilation" effect predicted by Albert Einstein's special theory of relativity"

"Physicists have verified a key prediction of Albert Einstein’s special theory of relativity with unprecedented accuracy. Experiments at a particle accelerator in Germany confirm that time moves slower for a moving clock than for a stationary one.

The work is the most stringent test yet of this ‘time-dilation’ effect, which Einstein predicted. One of the consequences of this effect is that a person travelling in a high-speed rocket would age more slowly than people back on Earth.

Few scientists doubt that Einstein was right. But the mathematics describing the time-dilation effect are “fundamental to all physical theories”, says Thomas Udem, a physicist at the Max Planck Institute for Quantum Optics in Garching, Germany, who was not involved in the research. “It is of utmost importance to verify it with the best possible accuracy.”

The paper was published on September 16 in Physical Review Letters. It is the culmination of 15 years of work by an international group of collaborators including Nobel laureate Theodor Hänsch, director of the Max Planck optics institute"

 

more...............

Oh of course I trust the experiments and understand that some of our technology needs certain aspects of relativity to be true.  I am not trying to deny that.  Relativity is incomplete, at least at the quantum level.   So it seems possible that it could be corrected in other ways too.  And this issue I have seems, at least to me, to need a correction.

[studiot]

11 hours ago, 34student said:

This simply says that the universe, in its entirety and ontologically, has intrinsic properties A, B, C ..., but it also does not have intrinsic properties A, B, C....  At best it seems to be a consistent ontological contradiction. 

 

10 hours ago, 34student said:

Oh of course I trust the experiments and understand that some of our technology needs certain aspects of relativity to be true.  I am not trying to deny that.  Relativity is incomplete, at least at the quantum level.   So it seems possible that it could be corrected in other ways too.  And this issue I have seems, at least to me, to need a correction.

 

 

I thought you were making some progress towards a useful level of understanding.

Don't give up now.

 

Quote

Ontology is the branch of philosophy that studies concepts such as existence, being, becoming, and reality. It includes the questions of how entities are grouped into basic categories and which of these entities exist on the most fundamental level. Wikipedia

 

This is a science section, not philosophy or metaphysics.

Please remember that:

1) Even Einstein and Lorenz got things wrong and made invalid predictions (I have given some examples).
Even before them it was recognised that there were inconsistencies in previous theories.
Einstein resoved some of these inconsistencies, but introduced some new unknowns as a result.
That is all progress in Science and that process of progress is still ongoing today.

2) Spacetime is not the being, becoming or reality. It is a working model that has some characteristics the same as what we observe.
We can use that model to extract predictions about (only) some what we observe and also to explain some observations that earlier theory failed to predict.

3) Spacetime has at least one characteristic not possessed by observations (reality ?)
In order to have 'world lines' it's grid system imposes an orientation constraint, not inherent in the stucture of observational reality is models.

 

So chin up and remember the way to eat an elephant  - little by little.

[joigus]

On 11/25/2021 at 3:17 AM, MigL said:

Finally a good question ... +1

An observer sees a 'foliation' of the 4 dimensional block.
The observer's FoR determines the orientation of the foliation with respect to the spatial/temporal dimensions.
This orientation will have varying lengths, and durations, for differing observers.

And all foliations are equally valid.

Just skimming through this. I don't want to encourage the OP to pursue what essentially looks like a fundamental confusion between 'world line' and 'field lines' à la Faraday. But I agree that that's a good question. Although unfortunately belongs in a different category and I don't think any of us has a ready answer to it.

[Markus Hanke]

22 hours ago, 34student said:

To a photon the universe is a pancake; to me it is spacious.  Is the universe spacious or is it a pancake?

It is meaningless to ask about “size” separate from a specific observer, since this measurement designates a relationship between two frames in spacetime. It’s not an intrinsic property.

Thus there’s no contradiction, because we are dealing with relational properties, so the ontology of this is also strictly relational. 

In other words - all observers are right, but only in their own local frames.

[beecee]

49 minutes ago, Markus Hanke said:

It is meaningless to ask about “size” separate from a specific observer, since this measurement designates a relationship between two frames in spacetime. It’s not an intrinsic property.

Thus there’s no contradiction, because we are dealing with relational properties, so the ontology of this is also strictly relational. 

In other words - all observers are right, but only in their own local frames.

Ahhh, so beautifully put, all three statements! it brings a tear to my eye and a lump to my throat! 😉 Thanks Marcus.

[34student]

On 11/26/2021 at 5:52 AM, studiot said:

 

 

 

I thought you were making some progress towards a useful level of understanding.

Don't give up now.

 

 

This is a science section, not philosophy or metaphysics.

Please remember that:

1) Even Einstein and Lorenz got things wrong and made invalid predictions (I have given some examples).
Even before them it was recognised that there were inconsistencies in previous theories.
Einstein resoved some of these inconsistencies, but introduced some new unknowns as a result.
That is all progress in Science and that process of progress is still ongoing today.

2) Spacetime is not the being, becoming or reality. It is a working model that has some characteristics the same as what we observe.
We can use that model to extract predictions about (only) some what we observe and also to explain some observations that earlier theory failed to predict.

3) Spacetime has at least one characteristic not possessed by observations (reality ?)
In order to have 'world lines' it's grid system imposes an orientation constraint, not inherent in the stucture of observational reality is models.

 

So chin up and remember the way to eat an elephant  - little by little.

Yes, I have a better understanding of the mechanics of GR.  But it is very unsettling to me.  Like you mention here, I want to chat more about this in philosophy.

On 11/26/2021 at 3:35 PM, Markus Hanke said:

It is meaningless to ask about “size” separate from a specific observer, since this measurement designates a relationship between two frames in spacetime. It’s not an intrinsic property.

Thus there’s no contradiction, because we are dealing with relational properties, so the ontology of this is also strictly relational. 

In other words - all observers are right, but only in their own local frames.

Size, maybe, but shape, no.  I might start a new thread in philosophy.