Relativity?

[davidm]

Anyway, answer the question about whether you read the links I gave you, or fuck off.

[Viveka]

Yes, that's correct. No one can see their OWN time dilation or length contraction -- that's called Galilean relativity -- as has ALSO been explained to you!

Galileo had everything right, except he knew nothing about electromagnetism. All this is wasted on you, of course.

Look at the boldfaced.

Yes, it's correct that no one perceives his OWN CLOCK slowing, or his OWN LENGTH contracting! As has been explained to you, this is Galilean relativity -- no one in constant uniform motion (inertial frame) can perform an experiment to distinguish from a rest frame!

You are such an ignoramus! You know NOTHING, yet babble on!

One last time:

DID YOU, OR DID NOT NOT, read the two links I gave you that explain the resolution to this so-called "twin's paradox?"

YES OR NO?

If you don't answer this question, you'll get no more responses from me.

I did not because it's A CONTRADICTION!

[davidm]

Nobody travelling with one of these clocks finds it to be moving slower.

Right. For the traveler, the clock ticks just as it did on earth.

Everybody measures that a moving clock is moving slower.

Right.

One person finds another's clock is moving slower and vice versa.

Right.

The apparent contradiction is relativity.

Apparent. Right.

If we are both on different ships passing one another on a foggy night, we see each other moving, and cannot know which one of us is moving.

Is that a contradiction?

Of course each ship must be in constant uniform motion. If so, the occupant of each ship is entitled to think of her ship at rest, and the other as moving.

[davidm]

Look at the boldfaced.

Yes, it's correct that no one perceives his OWN CLOCK slowing, or his OWN LENGTH contracting! As has been explained to you, this is Galilean relativity -- no one in constant uniform motion (inertial frame) can perform an experiment to distinguish from a rest frame!

You are such an ignoramus! You know NOTHING, yet babble on!

One last time:

DID YOU, OR DID NOT NOT, read the two links I gave you that explain the resolution to this so-called "twin's paradox?"

YES OR NO?

If you don't answer this question, you'll get no more responses from me.

I did not because it's A CONTRADICTION!

Thank you for FINALLY admitting that you did not read the two articles that show WHY IT IS NOT A CONTRADICTION!

[davidm]

Viveka: DEVOTED TO WILLFUL IGNORANCE!

[Viveka]

Viveka: DEVOTED TO WILLFUL IGNORANCE!

davidm: Master of Bandwagonery.

[Viveka]

Nobody travelling with one of these clocks finds it to be moving slower.

Right. For the traveler, the clock ticks just as it did on earth.

Everybody measures that a moving clock is moving slower.

Right.

One person finds another's clock is moving slower and vice versa.

Right.

The apparent contradiction is relativity.

Apparent. Right.

If we are both on different ships passing one another on a foggy night, we see each other moving, and cannot know which one of us is moving.

Is that a contradiction?

Of course each ship must be in constant uniform motion. If so, the occupant of each ship is entitled to think of her ship at rest, and the other as moving.

Reply to the Boldfaced: Then why is the speed of light invariant?

[davidm]

Nobody travelling with one of these clocks finds it to be moving slower.

Right. For the traveler, the clock ticks just as it did on earth.

Everybody measures that a moving clock is moving slower.

Right.

One person finds another's clock is moving slower and vice versa.

Right.

The apparent contradiction is relativity.

Apparent. Right.

If we are both on different ships passing one another on a foggy night, we see each other moving, and cannot know which one of us is moving.

Is that a contradiction?

Of course each ship must be in constant uniform motion. If so, the occupant of each ship is entitled to think of her ship at rest, and the other as moving.

Reply to the Boldfaced: Then why is the speed of light invariant?

Your reply to the boldface does not even make any sense. There is simply no point in talking to you; you lack even a rudimentary understanding of this topic.

[davidm]

Viveka: DEVOTED TO WILLFUL IGNORANCE!

davidm: Master of Bandwagonery.

LOL. What a maroon!

[davidm]

Why won't you read the two articles that I linked, which will explain to you why what you think is a contradiction, is in fact NOT a contradiction?

Why won't you read them?

[uwot]

If anything, in Einstein's gedankenexperiment,I've been wondering if we have a train with a light-clock on it, and a man with a light-clock on the embankment what would happen? The light-clock would work by cycles of being reflected once up and once down for one full cycle. Now, when the train starts moving, does it, or does it not have the same time as the embankment clock?

What you have to remember is that special relativity describes what observers see when they pass each other with uniform relative velocity. If they continue with that uniform velocity, they will never know what the other's clock says, because they will simply be getting further and further away from each other.

So if I am looking at a clock that supposedly measures time, then when I close my eyes time suddenly stops?

There is no such thing as a clock that measures 'time' directly. All any clock can do is count events, be it the swing of a pendulum, or the 'vibrations' of atoms. It is completely arbitrary; it just happens that the Earth takes as long as it does to rotate, and that period, a day, has been divided up into 24 equal bits, hours, which then have been divided into 60 minutes, which in turn are divided into 60 seconds. It is these seconds, which are the basic unit of time and a second is defined as 9,192,631,770 wobbles of caesium, for no other reason than that if you multiply that by 60 twice and the product by 24, that is how many times caesium will wobble while the Earth completes one full rotation. (In fact it is even more specific, because the altitude has to be take account of, since these clocks are so accurate that they can detect time dilation due to gravity if they are separated by a couple of inches.)

The fact that they cannot see each other's clocks does not mean it has any physical relevance. If the train were made of glass, would that make a difference?

As I said above, special relativity describes what you will see when you pass another inertial frame with a fixed relative velocity. To be clear: velocity is speed in a straight line, so two inertial frames that pass each other in a straight line will never meet again, unless the conditions of special relativity are abandoned, they stop travelling at a fixed relative speed, one or both stop, turn around, and they get back together.
The bit that causes the confusion is that during the split second when the two frames pass each other. As they look at each other, the paths of any marble (see davidm), ball (read my blog) or light clock (that's Einstein) appears to be stretched out, regardless of who is actually moving. People (even some physicists) treat that split second as if it describes the whole of the universe. Which, as I'm sure you can appreciate, it doesn't.

If it does, then relativity is wrong because of simultaneity and non-relativity and regardless of motion the clocks would be in synchronicity.

If the conditions of special relativity are broken, so that the clocks stop their uniform motion and can be brought back together, then in all likelihood they will tell different times. That's the woefully misnamed 'Twin's Paradox', which was confirmed by Hafele-Keating and every subsequent test.

If it doesn't have the same time, then there's a contradiction since both clocks are set to be at the same time regardless of motion.

Are you assuming that there is some absolute time? Tell you what; read my blog: http://willijbouwman.blogspot.co.uk Better still, buy the book: https://www.amazon.co.uk/dp/1521884722

There HAS to be absolute time, otherwise the speed of light wouldn't be what it is. It's not the ticks of the clock that count, it's the speed of light!

Whether there is any such thing as "absolute time" is irrelevant. We cannot count absolute time, we can only count events. Seriously: this is way easier with pictures, which is why there are so many in my blog and book. There is a section called 'How does time work?' It's about half way down and it explains all of this as simply as I know how. Do yourself a favour and read it.

[thedoc]

Viveka: DEVOTED TO WILLFUL IGNORANCE!

Yep.

I must say I admire your perseverance, you must like banging your head against a brick wall.

[thedoc]

Relativity, it's all Relative.

[davidm]

What you have to remember is that special relativity describes what observers see when they pass each other with uniform relative velocity. If they continue with that uniform velocity, they will never know what the other's clock says, because they will simply be getting further and further away from each other.

So if I am looking at a clock that supposedly measures time, then when I close my eyes time suddenly stops?

There is no such thing as a clock that measures 'time' directly. All any clock can do is count events, be it the swing of a pendulum, or the 'vibrations' of atoms. It is completely arbitrary; it just happens that the Earth takes as long as it does to rotate, and that period, a day, has been divided up into 24 equal bits, hours, which then have been divided into 60 minutes, which in turn are divided into 60 seconds. It is these seconds, which are the basic unit of time and a second is defined as 9,192,631,770 wobbles of caesium, for no other reason than that if you multiply that by 60 twice and the product by 24, that is how many times caesium will wobble while the Earth completes one full rotation. (In fact it is even more specific, because the altitude has to be take account of, since these clocks are so accurate that they can detect time dilation due to gravity if they are separated by a couple of inches.)

The fact that they cannot see each other's clocks does not mean it has any physical relevance. If the train were made of glass, would that make a difference?

As I said above, special relativity describes what you will see when you pass another inertial frame with a fixed relative velocity. To be clear: velocity is speed in a straight line, so two inertial frames that pass each other in a straight line will never meet again, unless the conditions of special relativity are abandoned, they stop travelling at a fixed relative speed, one or both stop, turn around, and they get back together.
The bit that causes the confusion is that during the split second when the two frames pass each other. As they look at each other, the paths of any marble (see davidm), ball (read my blog) or light clock (that's Einstein) appears to be stretched out, regardless of who is actually moving. People (even some physicists) treat that split second as if it describes the whole of the universe. Which, as I'm sure you can appreciate, it doesn't.

If the conditions of special relativity are broken, so that the clocks stop their uniform motion and can be brought back together, then in all likelihood they will tell different times. That's the woefully misnamed 'Twin's Paradox', which was confirmed by Hafele-Keating and every subsequent test.
Are you assuming that there is some absolute time? Tell you what; read my blog: http://willijbouwman.blogspot.co.uk Better still, buy the book: https://www.amazon.co.uk/dp/1521884722

There HAS to be absolute time, otherwise the speed of light wouldn't be what it is. It's not the ticks of the clock that count, it's the speed of light!

Whether there is any such thing as "absolute time" is irrelevant. We cannot count absolute time, we can only count events. Seriously: this is way easier with pictures, which is why there are so many in my blog and book. There is a section called 'How does time work?' It's about half way down and it explains all of this as simply as I know how. Do yourself a favour and read it.

Nice work on time on your blog/book, uwot. And yes, I'm still buying the book, not just reading it online. For the blog, it would be helpful to have some kind of search function for keywords; I realize you can't link the graphical words, but perhaps you could add html words off to the side with key word anchor links in them.

But will viveka read it? After all, he/she already has declared that he/she will not read links that contradict what he/she already believes! And he/she has already linked to one releativity denier that someone at another forum linked to ... hmmm ...

thedoc, do you think viveka might actually be peacegirl?

[OuterLimits]

The case where each person is moving in a straight line relative to the other does create clock paradoxes which rely on a concept of extended simultaneity in an inertial frame. But the very idea of extended simultaneity is just a convenience, and can be done away with. There are cases in circling SR and also cases in GR where the clocks are seen moving faster in one case, and slower in the other, and paradoxes are not invoked.