[hamdani yusuf (OP)]

No. Both twins experience one each of accelerations north-south, west-east, south-north, and east-west. Just in a different order.

Do you think the acceleration in the trajectory of DCD has the same magnitude as in BCD?
Do they have equal amount of momentum change?

[alancalverd]

acceleration DC ≡ AB, CD ≡ BA, etc.

So ABC ≡ ADC, and on the journey CD or DA they should be in sync.

[hamdani yusuf (OP)]

At point C, first twin changes his velocity by 90 degrees, while second twin changes his velocity by 180 degrees.

[hamdani yusuf (OP)]

Just in case the problem description is not clear yet, you can watch my new video.

Twin Paradox 1 : Rectangular Route

Investigating the exact cause of asymmetry in twin paradox thought experiment through a rectangular route. It allows us to see if difference in time dilation experienced by the twins can be fully attributed to difference in acceleration, and how they correlate to each other.

[hamdani yusuf (OP)]

Einstein, Gravity, and the Twin Paradox (Einstein's 1918 Solution)

Surprisingly few people are aware of Einstein's preferred solution to the Twin Paradox, which he detailed in a 1918 paper. We examine this solution, purported to take place within the framework of General Relativity, in hopes of finally finding an explanation to the twin paradox that can appease our empathic skepticism. Along the way we learn a thing or two about the nature of gravity, the distinctions between special and general relativity, and the philosophy of motion.

[alancalverd]

At point C, first twin changes his velocity by 90 degrees, while second twin changes his velocity by 180 degrees.

But number one also changes through 90 degrees at B. Instead of a square, gradually shorten the BC and DA legs. Is there a singularity when the distance ABCD  suddenly longer or shorter than ADCDA? 

Instantaneous change of velocity implies infinite force, which will destroy a twin, so try radiusing the corners.

[alancalverd]

explanation to the twin paradox that can appease our empathic skepticism.

Since it has been demonstrated, it is about 50 years too late for skepticism. 

[paul cotter]

I reckon this discussion will be moving to the "new theories" zone fairly soon!

[hamdani yusuf (OP)]

At point C, first twin changes his velocity by 90 degrees, while second twin changes his velocity by 180 degrees.

But number one also changes through 90 degrees at B. Instead of a square, gradually shorten the BC and DA legs. Is there a singularity when the distance ABCD  suddenly longer or shorter than ADCDA? 

Instantaneous change of velocity implies infinite force, which will destroy a twin, so try radiusing the corners.

This is a thought experiment, and we limit the parameters to be considered at minimum, just barely enough to distinguish one hypothesis from the others.

[hamdani yusuf (OP)]

I reckon this discussion will be moving to the "new theories" zone fairly soon!

Einstein's theory can't be new. He's already dead.

[Halc]

I reckon this discussion will be moving to the "new theories" zone fairly soon!

Yet again, your instincts are good.  Seemed silly to create a new topic when this one was already here.

Hamdani, you seem to have a talent for hunting down links to wrong answers to things. It seems very deliberate. Please stop posting explanations in the main sections of the forum. That section is for questions about established theory, not assertions about alternatives, especially ones that are obviously wrong.  Ask questions there. Don't assert anything. Please!

I tire of moving so many of your posts down to the lighter side.

Perhaps I can show an example to determine whether or not acceleration can explain the asymmetrical effects of time dilation in twin paradox. Instead of going back and forth on a single straight line, we make both twins to go through a rectangular route.

It shows no such thing since your twins are never a different age when co-located.

But the second twin experiences higher acceleration to reverse direction.

This is wrong.
If you are positing them getting up to speed instantly, all accelerations are infinite (singular), and one cannot meaningfully say that one infinity is greater than another.
If you are positing that the acceleration is finite (100M g's say) but a very short duration, then everybody undergoes the exact same magnitude of acceleration at each corner since they must come to a stop, turn, and get going again.
If you round the corners, then the picture should show that. Indeed the acceleration magnitudes would be different since one ship takes point C at speed and the other stops, but only for a really short duration.

The solution to this is trivially solved by the method mentioned in reply 1 of the main topic. Speed of everybody is always identical in the frame where the letters don't move, so all clocks tick at the exact same rate all the time.  No differential aging will be observed.


The post below was too much and prompted all this stuff being moved here.

Einstein, Gravity, and the Twin Paradox (Einstein's 1918 Solution)

Surprisingly few people are aware of Einstein's preferred solution to the Twin Paradox, which he detailed in a 1918 paper. We examine this solution, purported to take place within the framework of General Relativity, in hopes of finally finding an explanation to the twin paradox that can appease our empathic skepticism. Along the way we learn a thing or two about the nature of gravity, the distinctions between special and general relativity, and the philosophy of motion.

It references a letter written to somebody in 1918, not a peer reviewed paper.  If the letter actually contains what the video shows, then it contains countless errors, some of which are pointed out in the video.  One of the worst is the claim of a 'uniform gravitational field' which cannot exist except under Newtonian physics.  There is no solution to the field equations which describe one. I would hope that Einstein would have known that by 1918, but who knows?  Gravity is about curved spacetime, and there is no curved spacetime in the twins scenario, so invoking equations of gravity in a non-local scenario not involving curved spacetime is entirely wrong.

[hamdani yusuf (OP)]

Hamdani, you seem to have a talent for hunting down links to wrong answers to things. It seems very deliberate. Please stop posting explanations in the main sections of the forum. That section is for questions about established theory, not assertions about alternatives, especially ones that are obviously wrong.  Ask questions there. Don't assert anything. Please!

What's considered established at some point, may no longer be the case a few decades or even years later. The videos in the OP also criticized what are considered as established explanations.
If what you are looking for is the most widely accepted explanation at present, then your best chance is by asking various AI chatbots, especially the newest versions, and compare the answers to their top competors. They are essentially statistics on steroids, as some AI researchers said. If your own explanation turns out to be different than theirs, it may be because you are believing a non-established science instead.

[hamdani yusuf (OP)]

It shows no such thing since your twins are never a different age when co-located.

What does it show when they are not co-located? How is the situation of one twin from the perspective the other?

[hamdani yusuf (OP)]

If you are positing them getting up to speed instantly, all accelerations are infinite (singular), and one cannot meaningfully say that one infinity is greater than another.
If you are positing that the acceleration is finite (100M g's say) but a very short duration, then everybody undergoes the exact same magnitude of acceleration at each corner since they must come to a stop, turn, and get going again.
If you round the corners, then the picture should show that. Indeed the acceleration magnitudes would be different since one ship takes point C at speed and the other stops, but only for a really short duration.

If the acceleration is done in circular manner, say 1 light second in circumference, while the twins travel at c/2, then to turn the direction by 90 degrees takes half second, while turning the direction by 180 degrees takes one second by maintaining their speed. Alternatively, if the second twin is only given half second to turn, he must turn around with smaller circle, thus higher centripetal acceleration.

[Halc]

What's considered established at some point, may no longer be the case a few decades or even years later.

All the trolls say this. If you don't want to be branded a troll, it probably isn't a good idea to quote their handbook.

Turns out that nobody ever overturned established theory (however wrong) by not first understanding the established theory. I defy you to find a single exception to that.
Nobody overturned established theory by entering "Einstein wrong" as their search criteria, which is one way to find denialist videos.

Chatbots are also known to be consistently wrong when it comes to questions with so much misinformation in the training materials.

What does it show when they are not co-located?

Differential aging is inapplicable to clocks that are not co-located. This is basic relativity of simultaneity, something you seem not to understand if you ask a question like that.

If the acceleration is done in circular manner, say 1 light second in circumference, while the twins travel at c/2, then to turn the direction by 90 degrees takes half second, while turning the direction by 180 degrees takes one second by maintaining their speed. Alternatively, if the second twin is only given half second to turn, he must turn around with smaller circle, thus higher centripetal acceleration.

Cool. I take it these distances and speeds are as measured in the Earth frame. Speed maintained throughout, but one takes half a second longer to get to the new course heading.  A couple fine details are missing, but assuming these turns are executed at exactly 90 or 180 degrees, there will indeed be differential aging when they meet at the end. Can you compute it? It's fairly trivial.  Which will be older, and by how much?  Most importantly, what do you think the example demonstrates?

If you can't compute this most basic thing, then what was the point of bringing it all up?

[hamdani yusuf (OP)]

All the trolls say this. If you don't want to be branded a troll, it probably isn't a good idea to quote their handbook.

It doesn't matter who said that. What's important is whether it's true or not.

[hamdani yusuf (OP)]

Nobody overturned established theory by entering "Einstein wrong" as their search criteria, which is one way to find denialist videos.

My search query was twin paradox. And the video agrees with Einstein.

[hamdani yusuf (OP)]

Chatbots are also known to be consistently wrong when it comes to questions with so much misinformation in the training materials.

If that's what happens, top scientists will point it out and the developers will have to correct the answers. Otherwise they will lose market share to their competitors.

[hamdani yusuf (OP)]

It's fairly trivial

What's more important is whether the equations accurately represent physical reality.

[hamdani yusuf (OP)]

what was the point of bringing it all up?

To determine if acceleration has any effect on the symmetry breaking in twin paradox, which is the currently most taught explanation. Also to see if the travelling twin can be a valid observer, and how he views the  time dilation experienced by the other twin.