Three Experiments Challenging SRT

Hi Masterov. Pleased to meet you.

I have explained how the sunspot phenomena has a lot to do with what happens in the UPPER LAYERS of the sun and the CORIOLIS effect on both the plasmaflowlines and the magenitfieldlines at that level, and so not directly related to the deep interior processes as such. So there is no need to further stress your point about the interior not being responsible for what happens at the surface over the 11-year cycle of sunspot phenomena. The explanation I gave AGREES with that part of your view. :)

Anyhow, please read my explanations to origin regarding sunspots coming in pairs and persisting until the magnetic fieldline/plasmaflow LOOPS break and the filed settles back to 'normal' pattern until the next build up of 'contortions' in the field/flow in the upper layers which again become visible as plasma/magnetic lines arcs and joining sunspot 'pole' pairs.

See? Just as the CORIOLIS affects Earth's flows in the ocean and the atmosphere, the sun's rotation causes twisting and knotting of plasma/magnetic flowline 'patterns' which eventually cause the turbulence/phenomena we observe on the sun.

When that turbulence/phenomena dies down because of plasmaflow and magnetic line 'reconnections' and the energy in the sunspot system is RELEASED into the corona/space, then the sun quietens down and the solar cycle buildup begins again because the sun is still rotation and the turbulence/twisting and knotting gets more strong/massive and eventually becomes visible again.

I have no comment on whether a comet would actually reach the sun surface before being disintegrated by its transit of the much hotter CORONA. Nor do I make comment on whether any such 'incoming' material/bodies would ADD to any turbulence already caused by the sun's coriolis effects.

Perhaps in view of my explanations on 'sunspots' causes/phenomena, it might be prudent to go back and review your own take on sunspots and leave this OFF-TOPIC discussion for another time/thread, and meanwhile get back to concentrating on the main topic of your thread here!

Good luck and good thinking to you, Masterov, everyone!
 
How you got this issue from the quotation?
----------------------

Do I know the answer to a question "Why wind blow?"?

Yes, I know.
I understand a natures of a winds, tornadoes and hurricanes.

But I would like to have seen all that the answer to this question of physics do not know.
The answer to this question is not known even by those physicists who predict the weather.
It is for this reason we have such a bad weather forecast.

The answer to this question is the key to understanding the mechanism of generation of a tornado.
And in general: without this answer will remain a mystery to scientists many atmospheric processes.

For example: Coriolis force is practical value in the weather is not.
-----------------

Do you know: why the dewfall into sunrise?

There were two separate ideas in my earlier post to you;

1) I was complementing you on the humour, intended or unintended, of your statement "PS If you do not remind me of you in the future, I do forget you again". It just sounded funny. No big deal.

2) I asked you if you knew why wind blows, seeing as you have said no one else really does.

I don't think you answered (2) at all in any clear terms. Rather, you just went around the circle a little more. That's OK, but if you have a clear answer, as clear and as complementry to your "why wind blow" question, I would like to see it sometime.

Cheers !
 
You might not be familiar with the exact mathematical description, but what they're describing is simple enough. The first two equations I wrote (for a rotation) just depict this situation:

loc_eps_2dcartrot.gif

(Obtained by doing a Google image search for "rotation coordinates", which led me here.) What this is depicting is that if you start with certain x and y coordinates, then you can use a rotation to define two new coordinates x' and y' which are a certain mixture of the old x and y coordinates. The principle of rotational symmetry states that the laws of physics take the same form whether you write them in the (x, y) or (x', y') coordinates.

By analogy, a Lorentz boost depicted on a space-time diagram would look something like this:

K04_LorentzTransformation_html_m7999e174.gif

(Obtained near the end of the page here.) Relativity states that the laws of physics take the same form whether you write them in terms of the (t, x) or (t', x') coordinates.




Well it's difficult to derive concrete results without using mathematics, but as you can see above, the Lorentz boost defines new time coordinates t' and x' which are a certain mixture of the t and x coordinates. If you know that this is a symmetry in physics, then it's not hard to imagine you're going to get effects like time dilation out of it.

Beyond that, I don't see how I can help you. The fact that the Lorentz boost is a symmetry in physics is something we've discovered (originally lurking in electromagnetism, and we've found it well supported by experience ever since). We can't explain why things should be that way any more than we can explain why rotation should be a symmetry in physics. They just are, as far as our experience shows.

By the way, if the term "time dilation" itself is puzzling you, like you're reading it as saying that time itself slows down, then you're probably reading more into it than you really need to. All we can really objectively say is that, according to relativity, we expect physical objects and systems in motion to evolve or "age" more slowly than an equivalent system at rest. Because relativity states that this is due to a symmetry in physics, we expect the same result regardless of the internal details of the system in question. Beyond that is just a matter of personal philosophy. In physics, we care about what we can in principle measure - we're rather pragmatic about things in that respect - so and always by exactly the same factor, then we'll think that, for all practical purposes, we may as well say that "time" slows down.

Hi przyk.

The first diagram, above. Is this the same / similar thing and conveying the same / similar idea as contained in the web page you linked earlier, ie ..

https://en.wikipedia.org/wiki/Active_and_passive_transformation

If so, I think I've understood it. But I have no idea of what is meant by "Lorentz boost". I know I can google it, do some research, etc, but it's at these times that I end up hopelessly confused.

You've been rather successful in helping me in small steps thus far. Are you able to do the same with Lorentz Boost ? It would be good if you could.

I don't want to get too far ahead of myself, but regarding your last paragraph .. if we find that all moving objects evolve more slowly .. if you were moving away from earth and me in a spacehip at half c, between you and I, how is it determined that you're moving and I'm at rest ?

Thanks again for your perseverance !
 
Just as the CORIOLIS affects Earth's flows in the ocean and the atmosphere, the sun's rotation causes twisting and knotting of plasma/magnetic flowline 'patterns' which eventually cause the turbulence/phenomena we observe on the sun.
CORIOLIS affects?

The influence of CORIOLIS affects into the weather is negligible.
When you give an answer to my question ("Why wind blow?"), it will become apparent to you.

Ocean currents are created by winds.
A winds are author of ocean currents.
==============================

Влияние силы Кориолиса на погоду ничтожно.
Когда вы дадите ответ на мой вопрос, вам это станет очевидным.

Океанические течения создают ветры.
 
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But I have no idea of what is meant by "Lorentz boost". I know I can google it, do some research, etc, but it's at these times that I end up hopelessly confused.

I'm not sure what's confusing you, since I gave a diagram illustrating what a Lorentz boost is, by analogy with a rotation. The second diagram depicts a passive Lorentz boost on a space-time diagram. Do you understand what a space-time (or Minkowski) diagram is? If not, have you maybe seen distance-time graphs in, say, highschool physics or math? If you have, a Minkowski diagram is basically the same thing, except we like to put time on the vertical axis and distance on the horizontal axis.


I don't want to get too far ahead of myself, but regarding your last paragraph .. if we find that all moving objects evolve more slowly .. if you were moving away from earth and me in a spacehip at half c, between you and I, how is it determined that you're moving and I'm at rest ?

You couldn't determine that I was the one "really" moving and you were "really" the one at rest, if that's what you're asking. But you could easily determine that I was moving relative to you, away from you: you'd see me receding into the distance when you looked at me.

But like you say, you might be getting bit ahead of yourself. Just imagine there's such a thing as "given" or "absolute" rest for now if it makes you feel more comfortable. It will turn out that relativity means you will never be able to detect or measure such a thing, but maybe just pretend it exists and focus on trying to understand the Lorentz boost "one way" for now. After all, that would mirror the way physicists of the late 19[sup]th[/sup] and early 20[sup]th[/sup] century understood relativity as it was gradually being developed: they started thinking in terms of an "ether" frame which defined "absolute" rest, then started to realise that Lorentz symmetry meant that they would never be able to detect it and eventually abandoned the concept as unnecessary.
 
There were two separate ideas in my earlier post to you;I don't think you answered (2) at all in any clear terms. Rather, you just went around the circle a little more. That's OK, but if you have a clear answer, as clear and as complementry to your "why wind blow" question, I would like to see it sometime.
I no promised that I have intent provide an answer to my question.
I promised that I will prove that the answer to this question of physics do not know.
Judging by the fact that all eminent physicists decided not to answer my question, you can be sure that physicists embarrassed, and are unlikely to want to visit a photographer's studio.
Red faces (ashamed) of eminent physicists do damage for photos.

I will not give an answer to this question now.
If I answer to my question now, then everyone will say that they already knew the answer.
(I have this encountered often unpleasant thing formerly.)

Eminent physicists can not reply to a question from a school textbook during a week.

Shame on you, gentlemen of physics?
 
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CORIOLIS affects?

The influence of CORIOLIS affects into the weather is negligible.
When you give an answer to my question ("Why wind blow?"), it will become apparent to you.

Ocean currents are created by winds.
A winds are author of ocean currents.
==============================

Влияние силы Кориолиса на погоду ничтожно.
Когда вы дадите ответ на мой вопрос, вам это станет очевидным.

Океанические течения создают ветры.


I think I see what you are getting at, Masterov. I should have answered your question about winds first, then gone on to the coriolis component contribution to these.

First, convection involves warmer/lower-density atmospheric masses rising because colder/denser air masses push into and lift up the lowest regions of the rising air mass. This explains the 'horizontal' winds.

The convection currents themselves from vertical updraught 'winds' and downdraft winds (are these called 'micro-bursts'?...you know, those dangerously sudden vertical shear 'winds' which airplanes encounter at takeoff/landing).


Then there is the horizontal 'vortex' winds centred on the arctic/antarctic poles which there follow the earth's rotation at lower altitudes due to friction with the land/sea masses of the polar regions rotating with the earth's spin. As this polar air mass/vortex is colder/denser than in the equatorial regions, the outer streamlines of these polar vortexes moves to displace that tropical mass and force it to rise. This is interrupted at various latitudes by interaction between convection and vortex/coriolis affected windshears between moving air masses at various altitudes. But generally, the whole circulation/wind patterns are a result of all these interactions/factors mentioned.

The energy driving the system comes from the sun, and the polar regions and convection/coriolis mixing of the streams causes an overall turbulent pattern of vertical and horizontal and rotating masses/streams of atmospheric phenomena we call 'winds'. Some winds are 'prevailing' as large scale/persistent wind patterns; some are transient winds associated with storms and like local weather/seasonal patterns/events.


And then of course there is the OCEANIC WATER currents/loops.

The MAJOR LOOP CURRENTS can go deep and sometimes UPWELL when meeting an obstructing landmass. The normal 'thermal' density/convection process is affected by the salt water/rain etc which affects the strength and persistence of these loop flow currents.

Then there are the TRANSIENT or PREVAILING currents caused by friction between moving atmospheric masses (mostly horizontal winds). These may arise and subside as the winds go and subside and may interact with the more permanent loop currents at various depths. But these surface/wind currents don't seem to be influenced by the coriolis effect unless they are extensive geographically. Usually the 'ocean gyres' are the result of interaction between the land masses and loop currents which eventually extend to the surface. But the winds only affect an existing gyre at its surface layers only; and only transiently, as in hurricanes/storms.


Anyhow, Masterove. I tried to give a brief/rushed answer to your question about the winds. Now back to the sun...

The sun, having no 'landmasses', do not have upwellings of deeper plasma/magnetic current loops unless the heat-energy within those loops makes them slowly rise. Meanwhile AT THE SURFACE, there is the phenomena which I already explained. That is what causes the sunspots to build up in strength/frequency over the 11-year cycle. It is the surface layers being caught up in the TWISTING and KNOTTING of the magnetic field lines and plasma flows at that turbulent level. The sun's spin causes the magnetic fields to writhe, and the plasma to roil, such that eventually these upper layer flow/currents get twisted by the coriolis effect on the plasma 'ocean' currents the magnetic distortions of the sun's rotation on its field pattern.


Sorry, I have to go now. That's a briefly/hurriedly as I can answer your question and connect that to the sun's surface plasma/magnetic field 'sunspots' phenomena, Masterov. Good luck!
 
The wind is blowing from there, where the atmospheric pressure is greater, and blowing into where the atmospheric pressure is less.
Coriolis effect is not relevant to this process.
==============================

Ветер дует оттуда, где атмосферное давление больше, дует туда, где атмосферное давление меньше.
Эффект Кориолиса к этому процессу отношения не имеет.
 
Compare these pictures.
sun040815-c3-c1.jpg

1302960487_100001552.jpg

The lower photo shows the internal dynamics of the Jovian atmosphere.
This process is comprehensive.

The internal dynamics of Sun is completely absent, except in a sunspot.
The internal dynamics of Sun absent everywhere, only in a tiny area of a sunspot it occurs.

Only a crippled-mind can to believe that the first photo shows the internal dynamics of the Sun.
 
The internal dynamics of Sun is completely absent, except in a sunspot.
The internal dynamics of Sun absent everywhere, only in a tiny area of a sunspot it occurs.

Only a crippled-mind can to believe that the first photo shows the internal dynamics of the Sun.

So your contention is that a high energy plasma surrounding a fusion reactor core will have the same dynamics as a low temperature atmosphere of a gas giant planet? Really you believe that?

Geeze, talk about a crippled mind...
 
So your contention is that a high energy plasma surrounding a fusion reactor core will have the same dynamics as a low temperature atmosphere of a gas giant planet? Really you believe that?
If the internal dynamics of the Sun would have occurred, then it was shown on large areas, into all the sun's surface.
The spots have too small an area, and they have too many small details that had to be leveled.
============================

Если внутренняя динамика Солнца имела бы место, то она проявлялась на больших площадях, по все поверхности Солнца.
Пятна имеют слишком малую площадь и в них слишком много мелких деталей, которые обязаны были бы нивелироваться.
 
I'm not sure what's confusing you, since I gave a diagram illustrating what a Lorentz boost is, by analogy with a rotation. The second diagram depicts a passive Lorentz boost on a space-time diagram. Do you understand what a space-time (or Minkowski) diagram is? If not, have you maybe seen distance-time graphs in, say, highschool physics or math? If you have, a Minkowski diagram is basically the same thing, except we like to put time on the vertical axis and distance on the horizontal axis.

Yes, I do understand Minkowski's 4D block universe - I've read a good deal on it, and I've read C H Hinton of the same era and ideas too. Unfortunately I still can't get my mind around Lorentz boost. I think I need it explained in words, rather than diagrams or maths. Anyway, I'll spend more time on it.

You couldn't determine that I was the one "really" moving and you were "really" the one at rest, if that's what you're asking. But you could easily determine that I was moving relative to you, away from you: you'd see me receding into the distance when you looked at me.

I understand.

But like you say, you might be getting bit ahead of yourself. Just imagine there's such a thing as "given" or "absolute" rest for now if it makes you feel more comfortable. It will turn out that relativity means you will never be able to detect or measure such a thing, but maybe just pretend it exists and focus on trying to understand the Lorentz boost "one way" for now. After all, that would mirror the way physicists of the late 19[sup]th[/sup] and early 20[sup]th[/sup] century understood relativity as it was gradually being developed: they started thinking in terms of an "ether" frame which defined "absolute" rest, then started to realise that Lorentz symmetry meant that they would never be able to detect it and eventually abandoned the concept as unnecessary.

No, what I was getting at is exactly what you're saying, ie, you couldn't determine who was moving and who at rest. Therefore, my query is, in twin paradox, why does the 'travelling' twin age and not the one 'at rest' ?
 
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Yes, I do understand Minkowski's 4D block universe - I've read a good deal on it, and I've read C H Hinton of the same era and ideas too. Unfortunately I still can't get my mind around Lorentz boost. I think I need it explained in words, rather than diagrams or maths. Anyway, I'll spend more time on it.

Well in words, a Lorentz boost is a rotation-"like" transformation of the space and time coordinates. I think that's about as far as you can really go if you just want words. The thing is, we use math and diagrams in physics for a reason. You really can't advance very far without them.


No, what I was getting at is exactly what you're saying, ie, you couldn't determine who was moving and who at rest. Therefore, my query is, in twin paradox, why does the 'travelling' twin age and not the one 'at rest' ?

They both age. If the travelling twin is inertial (non-accelerating), then each twin is time-dilated with respect to the other. The reason that's possible is that when you're measuring the time dilation rate of a moving object, it matters how you define simultaneity - i.e. it matters how you consider that two clocks separated a certain distance are synchronised and reading the same time. In relativity, reciprocal time dilation (each twin considers the other to be ageing more slowly) is made possible by the fact that inertial observers moving at different velocities don't share the same concept of simultaneity: two events that happen at the same time according to one observer generally don't happen at the same time according to another observer.

Think of how you'd actually measure a moving object's time dilation factor. You can't sit the object next to your own clock because by definition the object is moving and your clock is supposed to be at rest. So one way to do it might be to lay out a bunch of synchronised clocks and cameras along a track, and then have an object with a clock attached to it move along the track near the speed of light. Then you could directly compare how the clock on the moving object was advancing as it passed by all the clocks you'd positioned along your track. The key point here is: you need more than one clock at rest, in different places, to measure the time dilation factor of a moving object, and the result you get depends on you correctly synchronising all your own clocks.

If you reverse the situation then you find it's not the same: if a moving observer wanted to measure your time dilation factor, then it's they who would need a whole array of synchronised clocks along a track, and you would only need one. The result they get depends on how they synchronise their clocks, and according to relativity their clocks won't be synchronised from your perspective. Obviously, that's going to affect the time dilation factor they measure for you, and in relativity it works out just in such a way that the moving observer measures the same time dilation factor for you as you would for them.

For the actual twin paradox, where the travelling twin stops and returns to Earth, the thing that makes the difference is that they have to accelerate to turn around and start returning. Their idea of simulateity (and consequently their idea of how old their twin on Earth is "now") can change very dramatically between before and after they accelerate, while the Earth twin's idea of simultaneity never changes because they never accelerate. That's why the Earth bound twin can simply and safely use relativity's time dilation formula to calculate how old the travelling twin will be when he returns, but the travelling twin cannot do the same: the travelling twin accelerated and switched from one inertial frame to another with a different definition of simultaneity, and if he wanted to calculate how old his twin on Earth would be when he returned, he would need to account for that.
 
The wind is blowing from there, where the atmospheric pressure is greater, and blowing into where the atmospheric pressure is less.
Coriolis effect is not relevant to this process.
==============================

Ветер дует оттуда, где атмосферное давление больше, дует туда, где атмосферное давление меньше.
Эффект Кориолиса к этому процессу отношения не имеет.

Hi Masterov.

Two points. One, the fluid on the sun is plasma, not just gas. Two, the plasma interacts strongly with the sun's overall strong magnetic field patterns, and the plasma flows create their own magnetic fields like currents through a wire.

I already said that the main reason for earth's winds is the displacement of 'lower density' masses by high pressure regions 'higher density' masses. Then that the CORIOLIS effect COMPLICATES/TWISTS etc the flows from just that displacement action.

Similarly on the sun, the coriolis effect AND the magnetic fieldline distortions due to sun rotations AND to plasma flows intiated by pressure differential, all 'build up' to produce twisting/looping regions where the plasma is trapped inside a closed loop magnetic containment 'circuit' which intersects the surface layers where the SPOTS appear. There are TWO spots associated with the loop, these are where one side of the loop comes UP through the surface to produce a 'north pole' feature in one spot, and the other where the loop is going down into the surface to create a 'south pole' spot feature.

Yes, the initial 'winds' are as we both said, due to low/high pressure differential driven flows horizontally. BUT then I pointed out where other factors complicate and twist and create wind closed loops which produce what we see as sunspots connected by the two arcs of this closed loop above and below the surface.

I trust this explains the 'complications' and 'sunspots' aspect above and beyond the simple/initial high/low pressure region 'wind' aspect? If so, then I suggest a return to the OP discussion and leave any further questions/discussion of sunspots and winds to OTHER threads which anyone can open if they want to pursue these other topics. Yes? :)

That's about it from me here. Cheers and good luck, Masterov, everyone!
 
Hi Masterov...
Hi, RealityCheck.

The answer to the question is very simple and obvious.
You complicate things.

Of course, that on a large scale (scale cyclone) and at high speeds (tornado) it is necessary consider the inertia of the air, its viscosity and friction by surface of Earth.

But in programs that predict the weather, the Coriolis effect is present and there is no link between the two important parameters.

If you remove the Coriolis effect and to link two unrelated parameter, the quality of the weather forecast will improve significantly.
======================

Ответ на вопрос очень прост и очевиден.
Ты всё усложняешь.

Разумеется, что на больших масштабах (масштаба циклона) и на высоких скоростях (торнадо) нужно учитывать инерцию воздуха, вязкость его и трение о поверхность.

Но в программах, которые прогнозируют погоду, присутствует эффект Кориолиса и отсутствует связь между двумя важными параметрами.

Если убрать эффект Кориолиса и связать два несвязанных между собой параметра, то качество прогноза погоды улучшится в разы.
 
If the internal dynamics of the Sun would have occurred, then it was shown on large areas, into all the sun's surface.
Why?
Because the internal dynamics occurs at a depth below the surface.
Therefore it is called "internal dynamics".
There (at depth) small parts may exist.
For the surface detail is not accessible.
They will are smooth by convection currents and viscosity of gases of the solar atmosphere.
The spots have too small an area, and they have too many small details that had to be leveled.
Why is the area too small?
The properties of the surface layers of the solar atmosphere are uniform across the surface of the Sun.
Internal speaker (if there) would meet on the entire surface of the Sun.
 
Hi, RealityCheck.

The answer to the question is very simple and obvious.
You complicate things.

Of course, that on a large scale (scale cyclone) and at high speeds (tornado) it is necessary consider the inertia of the air, its viscosity and friction by surface of Earth.

But in programs that predict the weather, the Coriolis effect is present and there is no link between the two important parameters.

If you remove the Coriolis effect and to link two unrelated parameter, the quality of the weather forecast will improve significantly.
======================

Ответ на вопрос очень прост и очевиден.
Ты всё усложняешь.

Разумеется, что на больших масштабах (масштаба циклона) и на высоких скоростях (торнадо) нужно учитывать инерцию воздуха, вязкость его и трение о поверхность.

Но в программах, которые прогнозируют погоду, присутствует эффект Кориолиса и отсутствует связь между двумя важными параметрами.

Если убрать эффект Кориолиса и связать два несвязанных между собой параметра, то качество прогноза погоды улучшится в разы.


I point out further that mere horizontal winds and convection does not produce the most intense/widespread 'weather' effects.

The heat/energy transport between lower and upper atmosphere is made more efficient/violent by cyclonic 'funnels' systems that speed up the air mass movements from lower to higher altitudes and vice versa.

So the horizontal winds are mere 'precursors' to what the weather will be doing at any locality/region. For example, during winter here, there are prevailing winds that bring cooler air into warmer air regions. They cause the usual rising/condensation rain episodes.

But when the winds are part of a cyclonic system which meets another cyclonic system spinning in the opposite direction, their BOUNDARY regions meet and RE-INFORCE the wind speeds of both to more than they would be in isolation. This creates windSTORMS and violent/accelerated precipitation and up/down draughts etc and spawn smaller localised 'MINI cyclones' etc etc.

So, both the combined cyclonic 'complications', and the stronger isolated hurricane systems feeding off oceanic energy, are complications which are spawned by the coriolis effect to give them their initial 'SPINUP' motion which is then intensified by the energy feeding into that initial 'core' feature.

Finally I wish to point out that CYCLONES in the SOUTHERN hemisphere SPIN CLOCKWISE; while those in the NORTHERN hemisphere SPIN COUNTERCLOCKWISE. That is due to the earth's spin interacting via FRICTION (the CORIOLIS effect) with the air masses moving FROM THE POLES in the initial horizontal wind steams which THEN become 'cyclonic' in their respective spin direction depending on which pole the mass came from. See? The Coriolis effect IS A VERY important factor in both the earth and sun surface/flow dynamics which we can observe in the wider picture which produces sunspots/waves etc on the sun.


Now, as for the sun dynamics, just ADD the plasma/magnetic flow line contortions I menationed earlier, and you can see that cyclonic/loop flows on the sun CAN occur due to distortions/redirections of the horizontal 'winds' into the sunspot phenomena 'loops/cyclonic' features which I have explained are associated with sunspots where these loop/cyclonic streams go down/up through the sun's srface to just below the top layers, and where the intersections are is where the 'spots' (north/south) appear.

I trust that further explanation will answer? :)

Again, may I suggest you drop this 'off-topic' aspect here and start another thread if you want to?

Gotta go! Cheers!
 
Because the internal dynamics occurs at a depth below the surface.
Therefore it is called "internal dynamics".
There (at depth) small parts may exist.
For the surface detail is not accessible.
They will are smooth by convection currents and viscosity of gases of the solar atmosphere.The properties of the surface layers of the solar atmosphere are uniform across the surface of the Sun.
Internal speaker (if there) would meet on the entire surface of the Sun.

Unfortunately the language barrier is making it impossible to understand what you are saying - it makes no difference in the long run though.
 
Well in words, a Lorentz boost is a rotation-"like" transformation of the space and time coordinates. I think that's about as far as you can really go if you just want words. The thing is, we use math and diagrams in physics for a reason. You really can't advance very far without them.




They both age. If the travelling twin is inertial (non-accelerating), then each twin is time-dilated with respect to the other. The reason that's possible is that when you're measuring the time dilation rate of a moving object, it matters how you define simultaneity - i.e. it matters how you consider that two clocks separated a certain distance are synchronised and reading the same time. In relativity, reciprocal time dilation (each twin considers the other to be ageing more slowly) is made possible by the fact that inertial observers moving at different velocities don't share the same concept of simultaneity: two events that happen at the same time according to one observer generally don't happen at the same time according to another observer.

Think of how you'd actually measure a moving object's time dilation factor. You can't sit the object next to your own clock because by definition the object is moving and your clock is supposed to be at rest. So one way to do it might be to lay out a bunch of synchronised clocks and cameras along a track, and then have an object with a clock attached to it move along the track near the speed of light. Then you could directly compare how the clock on the moving object was advancing as it passed by all the clocks you'd positioned along your track. The key point here is: you need more than one clock at rest, in different places, to measure the time dilation factor of a moving object, and the result you get depends on you correctly synchronising all your own clocks.

If you reverse the situation then you find it's not the same: if a moving observer wanted to measure your time dilation factor, then it's they who would need a whole array of synchronised clocks along a track, and you would only need one. The result they get depends on how they synchronise their clocks, and according to relativity their clocks won't be synchronised from your perspective. Obviously, that's going to affect the time dilation factor they measure for you, and in relativity it works out just in such a way that the moving observer measures the same time dilation factor for you as you would for them.

For the actual twin paradox, where the travelling twin stops and returns to Earth, the thing that makes the difference is that they have to accelerate to turn around and start returning. Their idea of simulateity (and consequently their idea of how old their twin on Earth is "now") can change very dramatically between before and after they accelerate, while the Earth twin's idea of simultaneity never changes because they never accelerate. That's why the Earth bound twin can simply and safely use relativity's time dilation formula to calculate how old the travelling twin will be when he returns, but the travelling twin cannot do the same: the travelling twin accelerated and switched from one inertial frame to another with a different definition of simultaneity, and if he wanted to calculate how old his twin on Earth would be when he returned, he would need to account for that.

Thanks for the response przyk. I gotta think a lot about this before blurting out a reply, so I'll take some time.
 
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