High School Why will an object in space continue moving foever?

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An object in space continues moving indefinitely due to Newton's first law, which states that an object in motion stays in motion unless acted upon by an external force. This principle is supported by experimental evidence, affirming the law's validity across various scenarios. The law of conservation of momentum also stems from the idea that physical laws are consistent throughout the universe. Noether's theorem connects conservation laws with symmetries in physics, illustrating deeper relationships between momentum, position, and energy. Ultimately, these principles highlight the fundamental nature of motion in the absence of external influences.
THP
Why object in the space will continue moving foever if the object is in dynamic equilibrium?
 
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THP said:
Why object in the space will continue moving foever if the object is in dynamic equilibrium?
Are you asking which of Newton's Laws implies this, or why Newton's Laws are true?
 
I want to know why Newton's laws are true
 
THP said:
I want to know why Newton's laws are true
Scientific laws are ultimately based on experiment. Experiment agrees that Newton's first law holds good in all the situations where we have tested it.

One can drive a bit deeper. The law of conservation of momentum can be shown to follow from the principle that the laws of physics over here are the same as the laws of physics over there. Experiment agrees with that principle as well.

https://en.wikipedia.org/wiki/Noether's_theorem#Basic_illustrations_and_background
 
THP said:
Why object in the space will continue moving forever if the object is in dynamic equilibrium?
If you are moving and the object is at rest, it's an identical situation, and you certainly wouldn't expect space object to start moving out of the blue for no reason.
 
David Lewis said:
If you are moving and the object is at rest, it's an identical situation, and you certainly wouldn't expect space object to start moving out of the blue for no reason.
I don't think you can prove the correctness of Newton's law this way. You just shift the question.
As jbriggs wrote, the law was based on observation, while Noether's theorem shows how it follows if the laws of physics are the same everywhere, but there is no way to prove that either.

On Noether's theorems, I have always been intrigued by the pairing of concepts that arises in two contexts:
  • Momentum and position.
  • Angular momentum and angular position.
  • Energy and time.
In each case, conservation of the first follows from the laws of physics being invariant under displacements in the second.
In each case the (dot) product of the pair has dimension of action. Indeed, the product relates to the Planck/Heisenberg uncertainty.
 

Thread 'Reference frames, center of rotation, etc'

Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?
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