creation wrote: ↑January 15th, 2020, 10:28 am
What happens if I "launch" a photon out into space in the exact same direction of the journey?

Not much different, but it is easier to understand it this way.

Except for the rumbling of the rocket, and when I look out the window.

Perhaps, but that is irrelevant in this context.

How is the photon traveling in my reference frame, when I am travelling at 80% the speed of the photon, and we are also going in different directions?

And, what has launching the photon on the ground have some bearing on it would travel in the same way? The same way to what exactly?

Where was the photon launched if it is not on the ground the first time?

The photon is launched on the ground level when the rocket is already moving, and it is launched in the reference frame of the moving rocket, ie. inside the moving rocket.

Also, when you say " 'from' the photon to travel ..." do you mean " 'for' the photon to travel ..."?

Yes, you can take that as a sort of "finnism", an error due to my native language.

a) What is the time my trip takes?

3 years according to your clock, 5 years according to your twin brother's clock.

b) How is that time my trip takes, in accordance to my clocks in the rocket?

3 years.

c) And how much older am I when I arrive on the planet?

3 years.

Are you saying I travel 3 years when I arrive at the planet and I am 3 years older? Or, what?

Exactly.

Why 'MUST' my brother take into account that the rocket has arrived at the planet?

If I was my brother on earth and I measure the trip then the rocket would be 80% of 3 light years away with 2 more years to travel. But I am not on the earth because you said I am in the rocket, and from my calculations I am 80% of 3 light years away from earth, with 2 more years to go to my destination. If and when I put myself in my brother's perspective (or reference frame, or reference point) on earth also, I still observe that the rocket is 80% of 3 light years away from earth, with 2 more years to destination.

When I reach destination, and if I and my brother have powerful enough telescopes, then I and my brother could also verify how long the trip actually took.

That is when I land and look back at earth it would look like I only just left a few seconds ago, and to my brother he would have to wait another 5 more years (or 10 years from when I left) to see me land on the planet. But as I say, I do observe and see things differently than most people do.

What I really cannot understand here is HOW could I, in the rocket, have traveled further than light could have in the exact same time? But this will all depend on how long you say my trip took.

When this is explained to me logically and reasonably, then I will start seeing and understanding, hopefully, what it is that you and others observe and see here.

Unfortunately I am not very good at explaining things clearly so that everybody understands. On the other hand, these things are somewhat counterintuitive and you are not the only one who finds it difficult to get a clear insight into them. I am not sure if this forum is the right place to learn the basics of SR or GR.

If the only "logically possible conclusion", to you, is if he trip has taken a much 'longer' time measured with a clock in the reference from of the earth, in this case 5 years, then is the '5 years' the longer time, or the measured with a clock in earth's frame of reference time?

If the 5 years is the longer time, then what is the earth's measured time? Or, if the earth's measured time is the 5 years, then what is the longer time?

I am not sure what you mean. The trip takes 5 years measured in the reference frame of the Earth and 3 years measured in the reference frame of the rocket.

What does my clock read?

3 years.

But how many of these so and so many seconds are there in one of those 'years' that you are referring to here?

3,154e+7. I just looked it up.

But if I was to provide a examples or a thought experiment not to much different to the above, then would anyone like to question, (and/or challenge), me on what I write, like I have just here?

It remains to be seen.