Talk:Causality (physics)

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Help with this template Comments: edit – history – watch – refresh The idea of causality in physics is very important -- it is one of those principles that is so thoroughly built into the foundation of physical law that no-one would consider a theory in which it is violated! Nevertheless, the article as is is a bit unfocused. It needs to define causality clearly in the beginning, for example, and basically be a little more comprehensible to the reader. Terms like "light cone" could be introduced a little more gently. Perhaps better connections to other articles in physics could be made. Wesino 00:57, 29 November 2006 (UTC)

I've removed the bulk of the text that was here, because it was impartial, unencyclopedic, and seemed rather irrelevant. Much of it was also redundant, when paired with the text that I've moved here from the "physics" section of causality

--Anakolouthon 22:41 3 Jul 2003 (UTC)

It seems to me that causality could be more quantitatively defined in terms of information retained, the degree of correlation across an event boundary. Has anything been developed along those lines? Fairandbalanced 08:38, 23 Aug 2003 (UTC)

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[edit] Causal contact

The thing about the reader being in causal contact with Edward Witten due to an article on Wikipedia is... odd. I'm not quite sure what point it's trying to convey. It's also a self-reference. Is there an example more motivated by physics that can go there?

RSpeer 19:43, Apr 23, 2005 (UTC)

Well, it's trying to convey that even two things that seem completely independent and remote can still have some kind of causal effect on each other. For example, every particle in space exerts a gravitational force on all other particles. However, the magnitude of this force becomes really small as the distance between two particles becomes really large.

66.143.152.106 04:27, 3 December 2005 (UTC)

Note:Gravity,Electromagnetiscm,etc can be shielded,deflected or weakened (possibly to zero) effect.If we accept that interaction isn't instanteneous,it propogation is affected by the whole universe,it space curvature.magnetic fields,motion of gravity sources,etc.

[edit] Causality breakdown

In the quantum mechanical realm does causality not break down, and effect has the potential to preceed cause? I am currently looking for citation on this, I know that I read it somewhere on Wiki... --HantaVirus 13:57, 27 July 2006 (UTC)

[edit] The Nature of Causality

There are a wide range of views on causality:

1. To some (e.g. Karl Popper) causality is superfluous. Bertrand Russell said "In advanced science the word cause never occurs. Causality is a relic of a bygone age."

2. Others, like Judea Pearl and Nancy Cartwright are seeking to build a complex fundamental theory of causality (Causality, Cambridge U. Press, 2000)

3. At the other extreme Rafael Sorkin and L. Bombelli suggest that space and time do not exist but are only an approximation to a reality that is simply a discrete ordered set, a "causal set."

4. Or perhaps a theory of causality is simply the theory of functions. This is more or less my take on causality (and possibly that of Herb Simon).

R. Jones, Professor of Physics, Emporia State U. —The preceding unsigned comment was added by 164.113.103.49 (talk) 20:08, 6 December 2006 (UTC).

Those are all very interesting, but since this article is Causality (physics) and not Causality (philosophy) I don't see your point. Physical causality is experimentally verifiable, and a matter of objective measurement. Not philosophical masturbation. --75.49.222.55 01:25, 8 October 2007 (UTC)