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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: Rick Woods]
      #6215431 - 11/25/13 03:28 PM

Quote:

I can't help feeling that there must be a simple analogy that would give people like us at least a rough picture of the situation.





I sure hope so, Rick.

A square matrix? Otto, I picture a square of sedimentary rock embedded with fossilized sea shells... It's bad when you haven't the math training....


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dickbill
scholastic sledgehammer


Reged: 09/30/08

Re: Scary relativity new [Re: Otto Piechowski]
      #6215434 - 11/25/13 03:30 PM

...

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brentwood
Carpal Tunnel
*****

Reged: 11/04/05

Loc: BC Canada
Re: Scary relativity new [Re: Otto Piechowski]
      #6215438 - 11/25/13 03:31 PM

The page of gibberish I posted above was a google translation of a couple of questions in Bulgarian. It looked all right when I posted it, but it was in Cyrillic script so maybe that's why it came through as just numbers.
The point that I was trying to make is the same as Otto's, why post in a format that is unintelligible to most on here.
That maths makes no sense to me, I can't even get enough of it to ask any questions!


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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: dickbill]
      #6215445 - 11/25/13 03:34 PM

Quote:

...




Problem is, it's pretty sad too!


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choran
Carpal Tunnel
*****

Reged: 12/28/12

Re: Scary relativity new [Re: Crow Haven]
      #6215452 - 11/25/13 03:36 PM

I'm no expert, but the idea is that -- by postulate --ALL observers will always measure the speed of light as the same, regardless of their state of relative motion. SO, since that number c is FORCED to remain a constant, and since
velocity=distance/time, TIME is forced to change. Two postulates (constancy of light speed, and same rules of physics in all systems moving at constant velocity relative to one another) must be accepted, and the rest follows. If you accept the postulates, you must swallow that time is dilated.
My brief summary based on what I'm sure is an incomplete understanding.

It's all quite counterintuitive and hard (impossible?) to swallow.


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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: choran]
      #6215465 - 11/25/13 03:42 PM

Wow, that isn't intuitive. Has there been any physical experimental evidence or must this remain just a result through math?

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EJN
Carpal Tunnel
*****

Reged: 11/01/05

Loc: 53 miles west of Venus
Re: Scary relativity new [Re: Otto Piechowski]
      #6215466 - 11/25/13 03:43 PM

deleted

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Otto Piechowski
Pooh-Bah


Reged: 09/20/05

Loc: Lexington, KY
Re: Scary relativity new [Re: Crow Haven]
      #6215474 - 11/25/13 03:49 PM

If we are correct that the-gal-traveling-in-a-spaceship-at-near-c-velocity (whom hereafter for the sake of not using these silly hyphens, we will call SpaceGalNear-c), SpaceGalNear-c turns on the headlights. It is a dark stormy misty night in the universe. SpaceGalNear-c sees the light from her headlights go out ahead of her into the misty night at the speed of light; i.e. "c".

We, who are observing her, by the side of the road, see SpaceGalNear-c traveling at near-c, and we see the headlights of her spaceship turn on. But, instead of seeing the light of her headlights zooming away in front of her at the speed of light ("c") what we see is the light from the headlights almost statically holding place just in front of her spaceship; maybe just inching ahead a small bit every second.

Am I seeing this correctly? From the outside of observer the light from the headlight would be almost statically standing still in front of the headlight lamp of SpaceGalNear-c?

Otto


EDIT ADDITION BY Otto

This can work, I mean whereas the light beam seems near static to the observer but normal to SpaceGalNear-c; is if SpaceGalNear-c's time has really slowed down as perceived by the outside observer; as in almost down to t= nearly 0; then it would appear to be screeching away at light speed to SpaceGal, but to us it would appear near static.

But why does the time slow down?

Otto

Edited by Otto Piechowski (11/25/13 03:59 PM)


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dickbill
scholastic sledgehammer


Reged: 09/30/08

Re: Scary relativity new [Re: EJN]
      #6215476 - 11/25/13 03:49 PM

Quote:

ALL observers will always measure the speed of light as the same, regardless of their state of relative motion



That in itself is counterintuitive, so why would we start with a counterintuitive postulate?


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Otto Piechowski
Pooh-Bah


Reged: 09/20/05

Loc: Lexington, KY
Re: Scary relativity new [Re: EJN]
      #6215487 - 11/25/13 03:53 PM

so a square matrix is a container with 1s and 0s, whose place in the 9 positions within this container is determined by them following that formula related to i's and j's; "delta_ij = {1 if i = j, 0 if i <> j"

What does the "delta_ij" mean?

What does the "and i,j = 1 to 3" mean? I mean, what is the relevance to this statement (and i,j = 1 to 3) to the container with 1s and 0s?

Otto


EDIT ADDITION BY Otto

EJN, thank you for adding,

"If you are familiar with any programming languages,
a square matrix is a two-dimensional array with the
same numbers of rows & columns.

For example in VB,

Dim array(10, 10) as Integer


Clear as mud? "

Unfortunately, I had one class of fortran thirty some years ago. That's it. I really appreciate you trying to help me. But its over my head. Might as well be that Rosetta Stone and I have a baby's understanding of the one language.

I fear it would be a waste of your time to try to get me up to speed.

But I appreciate your trying.

Otto

Edited by Otto Piechowski (11/25/13 04:03 PM)


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choran
Carpal Tunnel
*****

Reged: 12/28/12

Re: Scary relativity new [Re: Crow Haven]
      #6215494 - 11/25/13 03:56 PM

One can argue endlessly about the results and what they mean, but yes, there are experiments that verify some of SR's predictions. Some that seem to contradict the predictions in Einstein's first paper on SR (Sagnac experiment, Dayton Miller experiments) are explained away due to problems/misunderstanding of the nature of the reference frame under consideration, or experimental error. It will drive you crazy, trust me, to try to understand it all. Most physicists accept SR as true. Argue against it at your own risk.

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EJN
Carpal Tunnel
*****

Reged: 11/01/05

Loc: 53 miles west of Venus
Re: Scary relativity new [Re: Otto Piechowski]
      #6215508 - 11/25/13 04:02 PM

deleted

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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: Otto Piechowski]
      #6215519 - 11/25/13 04:05 PM

Quote:

From the outside of observer the light from the headlight would be almost statically standing still in front of the headlight lamp of SpaceGalNear-c?






That's what comes to mind, Otto, when I try to visualize it. However, if this can happen, what is going on with light we observe from a star moving through space if we could observe it from "the side of the road" for example? Would that light also look like it was slowed down and not reaching out to infinity? Or what if we used a laser beam?

Sorry I don't know what to do with the square matrix, other than maybe using it for a good beading pattern....


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Otto Piechowski
Pooh-Bah


Reged: 09/20/05

Loc: Lexington, KY
Re: Scary relativity new [Re: EJN]
      #6215526 - 11/25/13 04:06 PM

OK, EJN I got that. I understand.

Danny, EJN, now that I understand (for the moment) what a square matrix is, what does the sin and cosine stuff mean, and why does it relate to the c+c=c headlight paradox?

Otto

EDIT ADDITION

I did use sines and cosines in trig once upon a time; but I taught myself trig; its been forty years; I know they have something to do with angles in a triangle; something about representing the angles numerically, maybe?

Otto

Edited by Otto Piechowski (11/25/13 04:11 PM)


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Otto Piechowski
Pooh-Bah


Reged: 09/20/05

Loc: Lexington, KY
Re: Scary relativity new [Re: Crow Haven]
      #6215536 - 11/25/13 04:10 PM

OK, a star moving at near light speed, spits out light.

I'm thinking.

Let's imagine a quasar traveling, because of universe expansion, relative to us at say (being silly), near-c. If its light has reached us, it has also had the same amount of time to go-out sideways from us; so, though it took forever from our perspective to get to us, it has also had forever to go sidewise to our point of view.

Maybe that explains what the quasar's perpendicular-to-us light is so far away from the quasar, but the gal's headlight light isn't; it's a matter of the total time of the scenario.

?

I'm guessing.

Otto


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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: choran]
      #6215539 - 11/25/13 04:11 PM

Thanks for that info on the experiments. Yes, I don't think I'm going to be able to wrap my head around this very well, but it is interesting to try to get a bit of understanding of it.

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choran
Carpal Tunnel
*****

Reged: 12/28/12

Re: Scary relativity new [Re: Otto Piechowski]
      #6215554 - 11/25/13 04:14 PM

The "C+C paradox" that you refer to is simply a consequence of the first postulate: "The speed of light will always be measured at C, regardless of the state of motion of the light source, or the state of motion of the observer."
You have to accept the postulates and work from there to the consequences.
The matrices are tools used in linear algebra, (they are n x m arrays of numbers which can be manipulated and to which operations can be done). Linear algebra is a course offered a year or so after calculus, or at least that was the case when I was in school.


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The Mighty Mo
professor emeritus


Reged: 10/12/13

Loc: South of North, North of South...
Re: Scary relativity *DELETED* new [Re: Otto Piechowski]
      #6215558 - 11/25/13 04:16 PM

Post deleted by The Mighty Mo

Edited by The Mighty Mo (11/25/13 04:19 PM)


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Crow Haven
Pooh-Bah


Reged: 01/09/09

Loc: Oregon USA
Re: Scary relativity new [Re: Otto Piechowski]
      #6215600 - 11/25/13 04:33 PM

Quote:

OK, a star moving at near light speed, spits out light.

I'm thinking.

Let's imagine a quasar traveling, because of universe expansion, relative to us at say (being silly), near-c. If its light has reached us, it has also had the same amount of time to go-out sideways from us; so, though it took forever from our perspective to get to us, it has also had forever to go sidewise to our point of view.

Maybe that explains what the quasar's perpendicular-to-us light is so far away from the quasar, but the gal's headlight light isn't; it's a matter of the total time of the scenario.

?

I'm guessing.

Otto




"It's a matter of the total time of the scenario." That sounds reasonable...but it's hard to ignore a picture of a light beam just hanging there in slo-motion, it would be fun to see it.


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GregLee1
professor emeritus


Reged: 07/21/13

Loc: Waimanalo, HI
Re: Scary relativity [Re: Otto Piechowski]
      #6215612 - 11/25/13 04:42 PM

Quote:

If its light has reached us, it has also had the same amount of time to go-out sideways from us; so, though it took forever from our perspective to get to us, it has also had forever to go sidewise to our point of view.




I'm having a lot of trouble following much of this discussion, mostly because of a sort of omniscient observer viewpoint that is apparent here. How can I see light that is going out sideways from a distant object? Well, I can't. The light has to reach my eyeball before I can see it.


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