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If I could place myself in lights point of view, as I moved through the universe than atmosphere then a body of water would I in a sense see each medium like a guy on an imaginary ship traveling at c Would view his travels? As normal? Whiile an observer might see some differences in the ships movement that might relate to relativity? Could a body of water be viewed as a distortion of spacetime? As an outside observer refraction presents a direction change, yet from the photons point of view there is no direction change its still going straight as an arrow?

Could this also also apply to gravatational lensing. We see the light as bending yet from the photons, or imaginary ships point of view there is no acceleration because it hasn’t changed direction? Inside the imaginary ship I wouldn’t see any change in distance either. Where from an observers posistion I might, well especially me, might be scratching my head questioning okay the path is curved, yet everyone keeps telling me it’s traveling at c.

Is this relativity in action?

Edited by jajrussel
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30 minutes ago, swansont said:

You can't. It's not a valid reference frame, and we don't have the physics that would describe what's going on from that point of view.

Really? Don't people do it all the time, or is it my wording? Isn't that what they do in just about every video on relativity? Is it that I am just not allowed to imagine moving at c? Is it because two different frames of reference are used so both have to be ignorant of the other? (If something turns without acceleration) what is it if not Relativity? See Note below...

As an observer in my frame of reference I have to see refraction as change of direction I understand and agree with that but how do I account for c and the extra distance if not Relativity?

Or, maybe I just totally screwed up the thought when I presented it...

Note - I should have written (turns without a velocity change)

Note - I really don't know how to word this question correctly...

 

Edited by jajrussel
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10 minutes ago, jajrussel said:

Really? Don't people do it all the time, or is it my wording? Isn't that what they do in just about every video on relativity?

They look at things from different reference frames, but not a photon's frame. We can say what happens to a photon in our frame, or some other frame — it travels at c. 

10 minutes ago, jajrussel said:

Is it that I am just not allowed to imagine moving at c?

The equations that govern transforms between frames have a 1-v2/c2 term in them. Zero is a problem, especially if you try and divide by it.

10 minutes ago, jajrussel said:

Is it because two different frames of reference are used so both have to be ignorant of the other? (If something turns without acceleration) what is it if not Relativity? See Note below...

As an observer in my frame of reference I have to see refraction as change of direction I understand and agree with that but how do I account for c and the extra distance if not Relativity?

What extra distance?

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2 minutes ago, swansont said:

We can say what happens to a photon in our frame, or some other frame — it travels at c. 

And that, in simple terms, is the problem with trying to use light as a frame of reference: light still has to be moving at c relative to you, even though you are moving at c. 

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40 minutes ago, jajrussel said:

 Is it that I am just not allowed to imagine moving at c?

 

It might be useful to try. When you are unable to do so in a manner consistent with physics it can give you some incite into why. IIRC this was part of Einstein's thought process.

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1 hour ago, swansont said:

 

What extra distance?

Wouldn't light from a distant star seen due to gravitational lensing have traveled further than the straight distance? Thus the extra distance that relativity explains?

Again, maybe I am confusing thoughts? The light travels at c. Does it take longer to travel the curve distance? Okay, maybe I am trying to reverse engineer the process then say, okay this is what it must be like from the photons view, and I am wrong in doing that...  Gravity applies a force to the photon it changes direction, the distance is accounted for by the force. Relativity, is not needed. Is this correct? The photons view is not needed?

1 hour ago, J.C.MacSwell said:

It might be useful to try. When you are unable to do so in a manner consistent with physics it can give you some incite into why. IIRC this was part of Einstein's thought process.

 

Thanks... Of course it would probably work better if I was Einstein. :)

 

(I meant to quote-(Strange) here) Its a little funny I had been reading a thread where you used the word refraction then it was pointed out politely that you meant the word reflection, when I started trying to take the photons view of. "As I leave the atmosphere medium and enter the body of water would I notice the change of direction that an observer would label as refraction." Thanks I've had fun thinking about it. Even if I'm wrong.

Edited by jajrussel
I give up. Why?
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37 minutes ago, jajrussel said:

Wouldn't light from a distant star seen due to gravitational lensing have traveled further than the straight distance? Thus the extra distance that relativity explains?

Again, maybe I am confusing thoughts? The light travels at c. Does it take longer to travel the curve distance? Okay, maybe I am trying to reverse engineer the process then say, okay this is what it must be like from the photons view, and I am wrong in doing that...  Gravity applies a force to the photon it changes direction, the distance is accounted for by the force. Relativity, is not needed. Is this correct? The photons view is not needed?

Thanks... Of course it would probably work better if I was Einstein. :)

This is more perceptive than you perhaps realise.

 

The principle of least time (Fermat) is now over 350 years old but still stands.

Light takes the path of least time.

In those days the size and shape of the Universe was assumed fixed.

However in the last 35 years we have come to the startling conclusion that the shape and measurement of size (indeed its very geometry) varies with the scale over which you measure it.

The work of Richard Hamilton between say 1980 and 2000 started this and the Perelman received the Fields medal in 2006 for his proof of the Poincare conjecture (and more) which underlies it all.

 

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

Edited by studiot
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1 hour ago, jajrussel said:

Wouldn't light from a distant star seen due to gravitational lensing have traveled further than the straight distance? Thus the extra distance that relativity explains?

Again, maybe I am confusing thoughts? The light travels at c. Does it take longer to travel the curve distance? Okay, maybe I am trying to reverse engineer the process then say, okay this is what it must be like from the photons view, and I am wrong in doing that...  Gravity applies a force to the photon it changes direction, the distance is accounted for by the force. Relativity, is not needed. Is this correct? The photons view is not needed?

You will either observe a greater distance, or time dilation (which is called Shapiro delay). The local observer sees the photon traveling a straight path. A remote observer sees the path change.

 

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18 minutes ago, swansont said:

You will either observe a greater distance, or time dilation (which is called Shapiro delay). The local observer sees the photon traveling a straight path. A remote observer sees the path change.

 

Thanks, I'll look this up soon as I'm finished here. I thought time dilation was due to spacial distortion, or warped space. Sometimes I get hung up on an expression that would have been better expressed a different way to convey a clearer meaning. Then I really get it tangled up when trying to straighten it out while at the same time trying to figure out where I went wrong.

1 hour ago, studiot said:

This is more perceptive than you perhaps realise.

 

The principle of least time (Fermat) is now over 350 years old but still stands.

Light takes the path of least time.

In those days the size and shape of the Universe was assumed fixed.

However in the last 35 years we have come to the startling conclusion that the shape and measurement of size (indeed its very geometry) varies with the scale over which you measure it.

The work of Richard Hamilton between say 1980 and 2000 started this and the Perelman received the Fields medal in 2006 for his proof of the Poincare conjecture (and more) which underlies it all.

 

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

Loved the article, but I would have bowed to the judgment of my betters before turning down the money.:)

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1 hour ago, jajrussel said:

Thanks, I'll look this up soon as I'm finished here. I thought time dilation was due to spacial distortion, or warped space. Sometimes I get hung up on an expression that would have been better expressed a different way to convey a clearer meaning. Then I really get it tangled up when trying to straighten it out while at the same time trying to figure out where I went wrong.

In a very general sense, you get one or the other, depending on your reference frame.  

One observer, making a  journey, sees that his/her path has shortened, so the trip didn't take as long as naively expected. An observer at the destination sees the trip as being a greater distance than the traveler claimed, but the traveler's clock ran slow. Both arrive at a consistent conclusion, but each sees a different aspect of relativity as being responsible.

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3 hours ago, studiot said:

This is more perceptive than you perhaps realise.

 

The principle of least time (Fermat) is now over 350 years old but still stands.

Light takes the path of least time.

In those days the size and shape of the Universe was assumed fixed.

However in the last 35 years we have come to the startling conclusion that the shape and measurement of size (indeed its very geometry) varies with the scale over which you measure it.

The work of Richard Hamilton between say 1980 and 2000 started this and the Perelman received the Fields medal in 2006 for his proof of the Poincare conjecture (and more) which underlies it all.

 

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

I can see a connection to Fermat's Principle, because it was refraction that put me on the thought. From there I started trying to apply the thought to Relativity, but I am having a difficult time making the connection to Grigori Perelman. I found a somewhat broken connection between Fermat, and Perelman in that both of their works were to a degree related to two different men named Hamilton. So, somewhat broken. My question is, are you saying that Perelman used Fermat's Principle in his work? Which is possible by my limited understanding, but I would have to read more than an article about him to see the connection if they failed to make the connection obvious in the article. I was reading kind of fast so, I might have missed it if they did.

An interest in manifolds was sparked the other day when researching quadrupoles, but my head started spinning. I should make another effort. At the least I might figure out why the man said no to a million Dollars..... Nope... That won't ever happen

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You might get some value out of Donal O'Shea's book

The Poincare conjecture.

O'Shea is professor of Mathematics at Mount Holyoke in Massachusetts, in particular the maths of this type of geometry.
He strikes me as a bit like ajb here. Genial and approachable.

Anyway the book is popsci really but correct, unlike those written by journalists.

Sir William Hamilton was a 19th century Irish Mathematician who invented Quaternions (These are mentioned in the book)

Richard Hamilton is a current day American Mathematician who discovered the geometric manifold conjecture.

Fermat was totally separate.

 

 

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Ya, I tried a Transformation of SR @ C, it starts to give nonsense answers to stuff even if you take two C frames minus each other the geometries work but the answers are definitely not correct. See, I tried to take Gravity @ C versus Rotation @ C to transform it down to not being undefined despite being not undefined it gave odd answers for vectors within the geometric shape and not the geometric shape or vertices. 

IC412609.png

lightcone+basic.gif

 

In any case, you cannot use the Light-like Worldline as a base reference frame or you get some really inaccurate answers at certain times for time-like worldlines, why because half the cone is in space while the other half is in time, the left edge is the time-like vector at that point where the right edge is a space-like vector, where zero is Light-like Vector, it does not operate probably under those conditions.

lightcone.gif

5a17ed7a2a16f_151151684828827(2).gif.653125920098280006f209899d4f92ad.gif

Edited by Vmedvil
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