Is this an acceptable way to describe gravity

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Discussion Overview

The discussion revolves around alternative ways to describe gravity, particularly the phrasing of how matter and energy interact with spacetime. Participants explore the implications of different descriptions and their clarity, while also touching on related topics such as the Theory of Everything and fundamental forces.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that saying "space and time curve around the presence of matter and energy" could be an acceptable alternative to "matter and energy curve spacetime."
  • Others argue that there is no significant difference between the two statements, indicating a lack of clarity in the phrasing.
  • A participant expresses that the second description makes the concept clearer for them.
  • One participant contends that "space and time" should not be treated as separate from "spacetime," emphasizing the importance of viewing them as a single entity in general relativity.
  • Another participant notes that the wording of physical principles can be subjective and that mathematical expressions, like ##G_{ab} = 8\pi T_{ab}##, are more fundamental.
  • A participant introduces a question about the Theory of Everything and the representation of fundamental forces, seeking clarification on the absence of strong and weak nuclear forces in a graphic presented in a DVD.
  • Responses to this question suggest that it is better to start a new thread for new questions and that the participant should use Google for preliminary research.

Areas of Agreement / Disagreement

Participants express differing views on the phrasing of gravity descriptions, with no consensus on which description is preferable. Additionally, there is a lack of agreement on the appropriateness of discussing the Theory of Everything within the current thread.

Contextual Notes

Participants highlight the subjective nature of language in physics and the potential for ambiguity in phrasing. There are also indications that the discussion on the Theory of Everything may not fit well within the current thread's focus.

49ers2013Champ
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Instead of saying that matter and energy curve spacetime, could one say: space and time curve around the presence of matter and energy?
 
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I see literally no difference in those two statements.
 
Ha! That's good. Because when I read the second way of describing gravity, it makes things much clearer.
 
49ers2013Champ said:
Instead of saying that matter and energy curve spacetime, could one say: space and time curve around the presence of matter and energy?

No, I think the second part needs to be " ... spacetime curves around ... "

I don't think "space and time" is the same as "spacetime" since the former implies that they are separate things and that is NOT a good way of looking at things in GR.
 
Newton:

Do you agree with Phinds?
 
Honestly, I'm not a fan of putting things in words. The wording of physical principles can be quite subjective and ambiguous. As far as general relativity is concerned, ##G_{ab} = 8\pi T_{ab}## is the fundamental relationship between the matter fields and the space-time metric. You can decorate that statement however you like if it makes things clearer but the basic principle is as stated above. It is certainly true that space-time is a single entity but the semantic details can, as I said, be quite subjective and ambiguous. This is why things are presented mathematically.
 
Newton, I have another question, and I'll just ask it here instead of start another thread. I'm watching a DVD and it is discussing, among other things, the "Theory of Everything" and the way in which we'll arrive at it. Below is the graphic presented in the DVD.

Electricity...Magnetism (separation between these two) Gravity
Electromagnetism...Weak force
Electroweak force...color force
Grand Unified Force

Theory of Everything (arrows connecting gravity with Grand Unified Force)

Where are the strong and weak nuclear forces?
 
Last edited:
Just FYI, it is strongly discouraged on this forum to start a new question in the same thread. Start a new thread for a new question.

Also, Google is your friend. Strong and weak forces are very well-known terms.
 
Okay, Phinds. I'll ask it on another thread. I was just trying not to take up too much room.
 
  • #10
49ers2013Champ said:
Okay, Phinds. I'll ask it on another thread. I was just trying not to take up too much room.

Also, this is probably not the best forum to post questions about the strong and weak forces; either the quantum physics forum or the high energy particle physics forum would probably be better, if you have questions after you've Googled.
 
  • #11
49ers2013Champ said:
Okay, Phinds. I'll ask it on another thread. I was just trying not to take up too much room.

When you repost your question send me a PM and I can assist you on the TOE and GUT
 

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