How can it be that gravity can bend time and slow it down

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Discussion Overview

The discussion revolves around the relationship between gravity, time, and space, exploring how gravity can influence these dimensions. Participants examine theoretical concepts from general relativity, quantum mechanics, and philosophical interpretations of time and space.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that gravity influences spacetime by bending it, while others argue that gravity is the manifestation of bent space and time.
  • There is a suggestion that time dilation results from the deformation of space in a non-Euclidean metric.
  • One participant questions whether it is space that is deformed rather than time.
  • Another viewpoint asserts that time and space do not exist as separate entities but are constructs used to measure change, referencing concepts from quantum mechanics and relativity.
  • Some participants express skepticism about the existence of absolute distances, suggesting that measurements of time and space are inherently variable and observer-dependent.
  • A later reply discusses the self-consistency of Einstein's equations in general relativity, emphasizing the interdependence of spacetime measurements and the energy-momentum content.

Areas of Agreement / Disagreement

Participants express multiple competing views on the nature of gravity, time, and space, with no consensus reached on the fundamental questions raised.

Contextual Notes

Discussions include references to various theoretical frameworks and principles, such as Heisenberg's uncertainty principle and John A. Wheeler's participatory principle, which may influence interpretations of time and space but remain unresolved in this context.

cosmicpencil
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how can it be that gravity can bend time and slow it down, how can gravity influence a dimension of space?
 
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Anything with energy and momentum couples to the gravitational force/field thing and thus can bend spacetime inducing the effect we call gravity. Time dilation occurs because of the stretching and deforming of space in a non-euclidan metric.
 


so it is space that is deformed and not time?
 


gravity doesn't bend space or time. Gravity IS bent space and time. Or another way to look at it, bent space and time is what we call gravity. A better question is why does mass and energy bend space and time?
 


cosmicpencil said:
how can it be that gravity can bend time and slow it down, how can gravity influence a dimension of space?

Time does not exist nor does space.
Space is not some sort of massive container with no walls. You can not bottle some of it up and take it to your lab. QT may say that objects are not truly separated because entangled particles are in unison even if they are in different parts of the universe. QM says that "empty space" is filled with particles and fields. Einstein's Relativity says that there is no absolute distance between objects because distances can mutate due to gravity and velocity.

Time is only the sum of spatial states in your mind. Time is a word we use to measure change not some kind of invisible matrix/web in which these changes occur. Its the way we think to make sense of things.

See: Heisenberg's uncertainty principle, Quantum Mechanics, Quantum Theory, John A. Wheeler's participatory principle, Einstein's relativity
 


Belzy said:
Time does not exist nor does space.

What a coincidence, that's exactly what Abraham Lincoln was telling me when we had lunch on the moon in 3018.
 


Belzy said:
Time does not exist nor does space.
Space is not some sort of massive container with no walls. You can not bottle some of it up and take it to your lab. QT may say that objects are not truly separated because entangled particles are in unison even if they are in different parts of the universe. QM says that "empty space" is filled with particles and fields. Einstein's Relativity says that there is no absolute distance between objects because distances can mutate due to gravity and velocity.

Time is only the sum of spatial states in your mind. Time is a word we use to measure change not some kind of invisible matrix/web in which these changes occur. Its the way we think to make sense of things.

See: Heisenberg's uncertainty principle, Quantum Mechanics, Quantum Theory, John A. Wheeler's participatory principle, Einstein's relativity

thanks for the info. so then time is relevant only to the observer? and thus is suceptible to change from one one ''place'' to an other?
 


cosmicpencil said:
thanks for the info. so then time is relevant only to the observer? and thus is suceptible to change from one one ''place'' to an other?

Yes, and no because you can never be certain where anything is because there is no absolute distance between anything and anything else. Any measurement from different places will be different and any measurement from the exact same spot will be different. So time is not a "thing" it is a mental tool we use to measure the change of things.
 


TalonD said:
A better question is why does mass and energy bend space and time?

Most textbooks will say that general relativity (GR) is a theory of gravity, but there is another way to view Einstein's eqns (EE) of GR, i.e., as a self-consistency criterion between spacetime measurements and the energy-momentum content therein. The LHS of EE contains the Ricci tensor, scalar curvature and metric tensor combined into what is called the Einstein tensor (G). G is a mathematical description of the geometry of spacetime. The RHS of EE contains the stress-energy tensor (SET), which is a mathematical description of the matter, energy and momentum content of spacetime. Typically, EE are solved for the metric (tensor that describes spatiotemporal distances) having made simplifying assumptions about the nature of the SET. But, the components of the SET require (tacitly or explicitly) a knowledge of how one makes spatiotemporal measurements so you can't input SET without tacit assumptions about the metric. Technically speaking, SET is the functional derivative of the matter-energy Lagrangian with respect to the metric. So, you can't put SET into EE to get the metric because you need the metric for SET. And, you can't figure out the metric without SET in EE. Thus, GR is telling you how space, time, matter, energy, and momentum are self-consistently co-related.
 

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