# Discussion:Lorentz invariance of certain zero angles

It's moot anyway, as far as this debate is concerned.

prometheus said:
A vector is coordinate dependent (if you don't believe me write a general vector down and perform a coordinate transformation).

I don't think so. The coordinate representation of a vector in a particular basis is dependent on the chosen basis, but the vector itself is not dependent on any coordinate system.

As a simple example, consider a two-dimensional length vector attached to the origin in the (x,y) coordinate system. Obviously, it is represented as being composed of particular (x,y) coordinates - the coordinates of its "head" (the tail being fixed at (0,0)). Now consider a second coordinate system (x',y') that is rotated with respect to the first, and with co-located origins. The given vector obviously has a different coordinate representation in the new system, but the vector itself hasn't changed at all. To change the vector, we would have to change either its length or the direction it points in space. Going to a new coordinate system does neither of those things.

I don't think so. The coordinate representation of a vector in a particular basis is dependent on the chosen basis, but the vector itself is not dependent on any coordinate system.

As a simple example, consider a two-dimensional length vector attached to the origin in the (x,y) coordinate system. Obviously, it is represented as being composed of particular (x,y) coordinates - the coordinates of its "head" (the tail being fixed at (0,0)). Now consider a second coordinate system (x',y') that is rotated with respect to the first, and with co-located origins. The given vector obviously has a different coordinate representation in the new system, but the vector itself hasn't changed at all. To change the vector, we would have to change either its length or the direction it points in space. Going to a new coordinate system does neither of those things.

Yes that's true, but Tach was talking about the coordinate representation of a vector (at least that's how I read it.). I guess I should have been more careful...

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Hi Tach,
If you agree, I'd like to change the tracking list to rename the current issue as Definition of rods T1 and T2, and add Definition of points A and B, so we can focus on rods and points separately.

Hi Tach,
If you agree, I'd like to change the tracking list to rename the current issue as Definition of rods T1 and T2, and add Definition of points A and B, so we can focus on rods and points separately.

OK, cool

I can't edit the opening post any more.

Is it possible to turn off the edit time limitation for one post?

Otherwise, can someone please edit the opening post of [post=2863332]Debate: Lorentz invariance of certain zero angles[/post] to:
• Change "1.2 - Definition of T1 and T2 (Active)" to "1.2 - Definition of rods T1 and T2 (Active)"
• Add 1.3 - Definition of points A and B (Pending)

Thanks.

I can't edit the opening post any more.

Is it possible to turn off the edit time limitation for one post?

Not that I'm aware of.

Otherwise, can someone please edit the opening post of [post=2863332]Debate: Lorentz invariance of certain zero angles[/post] to:
• Change "1.2 - Definition of T1 and T2 (Active)" to "1.2 - Definition of rods T1 and T2 (Active)"
• Add 1.3 - Definition of points A and B (Pending)

Thanks.

Will do.

Thanks James.
Is it reasonable to keep making such requests as the debate continues, or should I come up with some other way of tracking the issues?

Hi Tach,
We agreed to answer direct questions in the next post.
To make this explicit, I think we should quote any direct questions and provide a direct answer as part of our response.
Pete said:
Do you agree that it defines the inertial rod T1, which is tangent to P at t=0 in S?

Thanks

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Hi Tach,
I don't quite agree after all - can I please amend my "Oh crap, wait" post to explain?

Hi Tach,
I don't quite agree after all - can I please amend my "Oh crap, wait" post to explain?

sure

Thanks, done.

Christ guys, 36 posts in the debate thread and you're "almost" done with step 1 of 4?

Christ guys, 36 posts in the debate thread and you're "almost" done with step 1 of 4?

Pete is attempting the impossible, (to get Tach to see one of his own errors), therefore this could take awhile. Although you did hand Tach his arse in pretty short order in the matte wheel debate, so maybe it can be done after all. But I don't think he ever acknowledged that he was incorrect about his claims, he just changed his claims around a bit.

Pete is attempting the impossible, (to get Tach to see one of his own errors), therefore this could take awhile. Although you did hand Tach his arse in pretty short order in the matte wheel debate,

Actually, it is the other way around, RJ handed his own arse to himself, I merely helped him along. Then , he threw a fit and threw the toys out of his pram. The same way you did it yourself, repeatedly.

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Actually I was thinking of this thread:

He had you in check-mate by post #5.

It shows that RJ learned from his debate fiasco and he went on to study in earnest, so I agreed with his new scenario, he finally learned the correct physics of reflection (at least the bit with matte surfaces, he, like you, still doesn't get the bit with the specular ones). So, he gathered his toys and put them back in his pram. When will you manage to follow suit?

Actually, it is the other way around, RJ handed his own arse to himself, I merely helped him along. Then , he threw a fit and threw the toys out of his pram. The same way you did it yourself, repeatedly.
Uhh, Tach, you do realize that I successfully debated the topic as I understood it, right? Ignoring for a moment whether or not the goal posts were moved after the debate began, does it make sense to you that I would use \$\$f_0\$\$=\$\$f_{s'}\$\$ in my proof unless I thought it bolstered my argument? Why the hell wouldn't I have simply used the argument that I laid out in the thread that Neddy Bate linked to...also written by me...and also completely devastating to your misconstrued beliefs?

I mean, if we're going to arbitrarily change how a debate topic should be interpreted then from now on I'm just going to claim that you were debating that 2+2=5. Oh yeah, and that you "self-destructed" in the effort.

this thread is for me and pete to discuss the debate, not for you two to whine about the debates you lost and not for you to do the trolling.

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You can tell, can't you? Having teeth pulled is no fun for anyone.