As a layperson, time travel seems impossible to me. Prove me wrong!

I answered that here

http://www.politicalforum.com/index...-prove-me-wrong.595435/page-6#post-1073175054

 

That was my argument, the past did exist, the future will exist, but neither do exist.

Quantum world, above my paygrade. I wish I could understand it, though.

I suspect you are referring to time dilation?

I think that has something to do with living in different spaces/places where the rate of change differs.

If you live in zone A, where the rate of change is like that of Earth, then go to another Planet B with much heavier gravity, there the rate of change is much slower, then return, others will have advanced in age compared to you.

Time dilation gives the illusion of time travel, but it's not time travel.

The change rate differs at different speeds or different gravitational force, and when living at a speed or different gravitational force where the change rate slows with respect to the origin point, and then returning, the illusion of traveling to the future is achieved.

But, in truth, the now is all that exists in any space. (As I understand it) both speed and gravity affect the rate of change. Some call it time, but time is just math, like inches on a ruler, it exists in the abstract.

But, WTF, I'm no scientist, this is just what makes sense to my sensibilities.

I'd be happy if someone could deeper my understanding of the quantum world or even thus subject..

 

This is very integral to the possibility of time travel, because if only the present frame of time exists, then there is no possibility of getting pushed back or sucked back in time. There would be no "leverage" to be able to do so.

As for the quantum effects, you might want to explore the phenomena of entanglement, where two different things seem to be linked over stretches of time and space. These correlations indirectly suggest it is not only the present that exists.

 

I'll basically agree with you here. Time dilation does not shows that slowing down time is possible. It does not show that jumping forward beyond the normal flow of time, or jumping backwards, is possible.

 

Time travel isn't possible, in other words, right?

do we know?

 

Actually scientists do not know for certain, but there are some strong indirect indications.

 

First is the key word appears. Think of this. Without the knowledge otherwise, the sun appears to move around the earth. Yet it is the fixed point in the reference of the solar system. Simply because it appears to you in such a way, does not mean it is not concrete. The illusion is its movement. the sun itself is concrete.

Secondly, you yourself acknowledged time dealation, which is in essence a warping of time. Thus by your own logic, time must be concrete in order to be warped. Or to take it in the opposite directioin, if you want to claim it is only the illusion of an illusion being warped, then that same logic can say that there is the illusion of the illusion of space being warped.

And now you contradict your previous post. Is the house any less real and concrete because we can get close and see the individual boards? No. Simply because you change your frame of reference it does not dismiss the other frames of reference. The house still remains real and concrete no matter how far down the building block chain we go. Likewise, time remains as concrete as wind and air (that is to say actual things in the world, even if it can't be touched by hands).

 

OK, I think this needs to be fixed just slightly.

If someone starts flying around in a spaceship at high speed, zooming near large masses or wherever else they want to go and they were thoughtful enough to bring along a super accurate clock, they would notice that time passes at 1 second per second for them. And, that is exactly what is happening. The clock isn't being fooled.

If someone on Earth watches a clock REALLY carefully as they sit on the couch, they will also see that time passes at 1 second per second. And, that clock isn't being fooled, either.

Time passes at the same rate whatever you are doing.

Where the difference comes in is that this universe is space-time. So, one can take different paths through spacetime.

Those different PATHS take different amounts of time to traverse.

Einstein even showed how to figure out how a path through space-time could be longer in terms of t.

If anyone can correct that or improve this description, please do. I am not a physicist.

 

@WillReadmore


It is said that space & time are the same thing. I think I have it, now. Thus I see it as true in the following sense:

Space is concrete.

Time is abstract.

Or, expressed in the following manner:

The outer is concrete,

The inner is abstract.

The inner and the outer are two sides of the same coin.

Expressed in terms of space v time, it's just another way of expressing the same thing

Space and time is concrete and abstract, respectively, and both are two sides of the same coin.

So, a mystic would say:

The outer and the inner are two sides of the same coin.

A scientist would say:

Space and Time are two sides of the same phenomenon, insofar as

the concrete and the abstract are two sides of the same phenomenon.

Right?

 

I don't know what that means.

Really? To me, what happens is that the point in time differs from "now", because time does not stop.

You can't have time be an illusion and space-time NOT be an illusion.

I don't see your use of language here as overwhelming what has been known about space-time since Einstein.

I suspect the terminology is getting in your way.

 

No, this is NOT what physics knows about space-time.

Time is a dimension of space-time that is just as real as the spacial dimensions. They come as a unit.

What you are claiming is like suggesting the x axis is "abstract" and the y axis is "concrete".

This has been tested continuously for more than 100 years now. And, it is STILL being tested, because this is a central issue of physics.

 

When I look, that is what I see, that the Time 'axis' is abstract, and the space 'axis' is concrete.

Does science assert that this is not true, that time is concrete?

 

Perhaps what you heard was meant to convey that time is just as much a dimension of space-time as are the spacial dimensions.

In that sense, one could say they are "the same thing", unfortunately somewhat misleading, maybe.

 

I've never heard any physicist use terms like that.

And, I don't know what "concrete" or "abstract" would mean when used that way.

What physicists say is that this universe is space-time.

And, they say that time passes at the same rate no matter what you are doing or how fast you are doing it. For you, time will always pass at one second per second.

However, clocks on fast objects like orbiting spacecraft near planets are taking a different path through time than are clocks that are moving with the surface of Earth. I know that sounds really weird.

It looks like time is passing at different rates. But, the truth is that the paths that the objects are taking through space-time are different lengths in the time dimension. So, for example, the clocks on GPS satellites don't match the clocks on Earth. And, the difference is large enough that correction on your smart phone mapping is absolutely required.

 

This is a very interesting take on things. Tell me if this rephrase is accurate to what you are saying. Someone who is traveling at 99% SOL round trip from earth and back (large loop to maintain speed most of the way) will return in say 5 years for them, but 30 years for those on Earth. So the space ship arrived at the space-time coordinates faster than the planet did. Does that sound correct?

 

First of all, it's not really true to say that we do not know the clock is being fooled.
There are some reasons why we cannot know who is the one being fooled, and who is the one actually standing still.

It has more to do with changes in speed (acceleration, deceleration) than it does with "paths".

No matter how fast you are going, you will never notice time being slower for you than it is on the outside, unless you experience change in velocity.

One of the big tennants of Relativity is that there is no way to know whether you are the one moving or whether someone else is.

 

The point I was making is that this is the way it works - that the clock is not fooling or being fooled, that time IS passing for that distant individual at 1 second per second given the reference frame of that individual. That's what the special theory of relativity holds.

There ARE differences in what some other observer might think while observing from some other frame of reference.

The concept of "whose moving" just doesn't even exist. There is no frame of reference to judge that by. The earth is rotating and revolving. The sun is revolving around the galaxy. The galaxy is revolving around the local super cluster, there is a world full of objects that all contribute accelerations, etc. There is nothing to suggest as a static point from which to determine movement.

However, one can measure relative motion between any two objects and one can pick either one or something else as the reference point. So, we can pick the sun as the reference point for measuring Mars movement, perhaps sometimes making the math a little easier than if Earth is the reference point.

 

Not to derail what you are saying, but rotation and revolution do not fall under the general theory of relativity.

 

OK, I should do some referencing of others rather than trying to use my own words.

I really like Dr. Sean Carroll, who is a theoretical physicist of some note and who really takes seriously the idea that he should be describing the physics he knows to the general public, while also doing serious theoretical physics, publishing serious papers, etc.

This one I see as important, because it establishes the change from the Newtonian view that there is space and there is time to what we've seen as space-time for the last 100 years.

It gets into time fairly seriously, but doesn't answer all qustions.

I listen to and read Dr. Sean Carroll. He's exceptionally clear about when he's presenting the standard models of physics or quantum mechanics and when he's presenting his own ideas.

So:
https://www.preposterousuniverse.com/blog/2020/04/28/the-biggest-ideas-in-the-universe-6-spacetime/

Preposterous universe is his own site.

After this one on special relativity and step from Newton to space-time is solid.

I don't have a link to his general relativity or to a time vid that shows more clearly what the deal is with clocks on satellites and time passage.

 

This is a video of physicist Sean Carroll in which he directly addresses your model of how time works - what exists/is real, etc.

He shows that an other models compare to Einstein physics.

https://www.preposterousuniverse.com/blog/2020/04/21/the-biggest-ideas-in-the-universe-5-time/

 

They still concern movement through space-time.

So for example special relativity is needed in calculating map address based on GPS satellite information.

 

Would you agree that past and future exist in the abstract?

 

Let's just look at it.

The past did exist, and so it's now memory, an abstraction.

The future will exist, so we can only think about it, so still an abstraction.

THe abstract space is real, but it is not concrete. It exists solely in the mind.

The abstract space is functionable, and we need the abstract space to function in the world, but, in and of itself, the abstract space is not concrete, you can't touch it, travel to it, put it in a jar, etc.

Does that make sense?

I'm not going by anything I've ever read on the subject, I'm going by my direct observation.

Can you do the same, and see what I'm seeing?

 

I'll check it out.

 

Okay, I've changed my mind about time being an illusion.


The term 'illusion' suggests something doesn't exist either in the concrete nor abstract.

Time exists in the abstract, so it's not an illusion, it's real because it's functionable.

An illusion is a mirage, a hallucination. When something is an illusion, the concrete tricks us to imagine something that isn't there.

That is not what is happening with time.

Therefore, when I claimed time is an illusion, I was wrong.

It's real, but exists in the abstract, and proof that it is real is that it is functionable.

I'm about halfway through the video, and it seems I'm a presentist, or closer to it, and, not an 'eternalist', as he presents himself

However, nothing he says changes the fact that the past, and the future, exist in the abstract. As an 'eternalist', he gives the 'realness' of the past, present, and future the same weight. But, that is just another way of looking at it. I suppose.

I don't think my way of looking at this conflicts with what he is saying.

I"ll continue to watch the video.

when I used the phrase 'abstract space' I was using the term 'space' figuratively.

Since, in science, it is better to avoid figures of speech, and be precise, and to be precise, there is no space in the abstract, it is spaceless, so I will not refer to it that way, any longer.