How does time work? Pt II Special Relativity.

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uwot
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How does time work? Pt II Special Relativity.

Post by uwot »

More adventures of Stickman. This time it's all the weird stuff about time slowing down. (It's not really weird.) http://willijbouwman.blogspot.co.uk
Impenitent
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Re: How does time work? Pt II Special Relativity.

Post by Impenitent »

a stick in the mud moves very slowly...

-Imp
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Arising_uk
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Re: How does time work? Pt II Special Relativity.

Post by Arising_uk »

You're gonna make a mint! :)
uwot
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Re: How does time work? Pt II Special Relativity.

Post by uwot »

Arising_uk wrote:You're gonna make a mint! :)
Great. I'll move in next to Reverend Bob.
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Noax
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Re: How does time work? Pt II Special Relativity.

Post by Noax »

uwot wrote:More adventures of Stickman. This time it's all the weird stuff about time slowing down. (It's not really weird.) http://willijbouwman.blogspot.co.uk
Good way to illustrate it. Haven't seen it put that way.

Remember to convey that time is not actually moving slower for Einstein. From his point of view (frame), it is stickwoman whose ball/light has further to travel and is the slow one. If there was one that was fast and one slow, it would be possible to determine which one was the one moving slower.
uwot
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Re: How does time work? Pt II Special Relativity.

Post by uwot »

Noax wrote:
uwot wrote:More adventures of Stickman. This time it's all the weird stuff about time slowing down. (It's not really weird.) http://willijbouwman.blogspot.co.uk
Good way to illustrate it. Haven't seen it put that way.
Thank you.
Noax wrote:Remember to convey that time is not actually moving slower for Einstein. From his point of view (frame), it is stickwoman whose ball/light has further to travel and is the slow one.
Well yes, time is relative, but our experience of it doesn't change. If the Twins Paradox is in any sense paradoxical, it is because even though what each other sees is equivalent, it is the case that in one inertial frame more happens than in the other...
Noax wrote:If there was one that was fast and one slow, it would be possible to determine which one was the one moving slower.
...which is exactly what Hafele-Keating demonstrated. All coming up in the next instalment.
uwot
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Re: How does time work? Pt II Special Relativity.

Post by uwot »

Impenitent wrote:a stick in the mud moves very slowly...

-Imp
As does one at the event horizon of a black hole. I'll get to that.
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Noax
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Re: How does time work? Pt II Special Relativity.

Post by Noax »

uwot wrote:Well yes, time is relative, but our experience of it doesn't change. If the Twins Paradox is in any sense paradoxical, it is because even though what each other sees is equivalent, it is the case that in one inertial frame more happens than in the other...
Don't put that in your blog since it violates the primary postulate of SR: All frames are equivalent and in no frame does "more happen" than in the other. In the case of the twins, in the frame of either twin, the other ages more slowly. This is true on both legs (out and back) of the journey. So in your example, Einstein notices that stickwoman seems to do everything slowly. There is no such thing as a 'slower frame' since velocity is not a property of a frame (or anything else).
Noax wrote:If there was one that was fast and one slow, it would be possible to determine which one was the one moving slower.
...which is exactly what Hafele-Keating demonstrated. All coming up in the next instalment.
That was not an experiment in inertial frames. That was accelerated frames, which are not inertial. 'Tis the acceleration (the "moment of acceleration" actually, a term Einstein used), not the speed, that gets you the time dilation. The experiment did not compare a fast thing vs. a slow thing.
uwot
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Re: How does time work? Pt II Special Relativity.

Post by uwot »

Noax wrote:
uwot wrote:...which is exactly what Hafele-Keating demonstrated. All coming up in the next instalment.
That was not an experiment in inertial frames. That was accelerated frames, which are not inertial.
Well yeah, in classical physics, but for the purposes of the blog, going into the niceties of the difference between absolute and relativistic space is a bit of overkill. Inertial frames are just mathematical tools, very handy for describing what two different observers see, but they simply do not exist in the physical world.
Noax wrote:'Tis the acceleration (the "moment of acceleration" actually, a term Einstein used), not the speed, that gets you the time dilation. The experiment did not compare a fast thing vs. a slow thing.
Yeah, but explaining that according to general relativity, level flight around the Earth is a straight line, because it follows the Earth's gravitational geodesic, I think is more information than is necessary to get the general idea of what actually happens.
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HexHammer
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Re: How does time work? Pt II Special Relativity.

Post by HexHammer »

Very poor illustration that will confuse more than it will enlighten people.
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Re: How does time work? Pt II Special Relativity.

Post by Belinda »

I am afraid I agree with Hexhammer. The little drawings are more lucid than the text. I wonder if the 'soft watches' (The Persisitence of Memory' by Salvador Dali) painting and suchlike explain relativity better. There is a place in the arts for explaining metaphysical ideas and even physical ideas as well.
uwot
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Re: How does time work? Pt II Special Relativity.

Post by uwot »

Horses for courses. I doubt there is any single explanation that will click for everyone. I'm sorry it doesn't work for either of you.
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Arising_uk
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Re: How does time work? Pt II Special Relativity.

Post by Arising_uk »

HexHammer wrote:Very poor illustration that will confuse more than it will enlighten people.
I think you think wrongly here.
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Arising_uk
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Re: How does time work? Pt II Special Relativity.

Post by Arising_uk »

Belinda wrote:I am afraid I agree with Hexhammer. The little drawings are more lucid than the text. I wonder if the 'soft watches' (The Persisitence of Memory' by Salvador Dali) painting and suchlike explain relativity better. ...
That'll be a no, unless of course someone write a text accompying the painting making such a connection and then reams trying to explain said connection.
There is a place in the arts for explaining metaphysical ideas and even physical ideas as well.
Maybe but in the end I thinks words and philosophy the better tools for such things.
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HexHammer
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Re: How does time work? Pt II Special Relativity.

Post by HexHammer »

Arising_uk wrote:
HexHammer wrote:Very poor illustration that will confuse more than it will enlighten people.
I think you think wrongly here.
No, I'm right! I put myself in the place of ppl with low spatial navigation, when you have high spatial navigation, the problem is you already have foreknowledge of this, thus you will not see the teaching flaws.
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