Understanding the Nature of Gravity and its Relationship to Energy Creation

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SUMMARY

This discussion centers on the nature of gravity and its relationship to energy creation, emphasizing that gravity is not a force in the context of general relativity but rather a pseudo force. Participants clarify that energy cannot be created or destroyed; instead, it transforms from potential energy to kinetic energy and then to thermal energy as matter interacts. The trampoline analogy for gravity is critiqued for oversimplifying the concept of spacetime, which is inherently four-dimensional. The conversation highlights the importance of understanding interaction energy in the context of gravitational attraction and energy transformation.

PREREQUISITES
  • Understanding of general relativity and its principles
  • Familiarity with Newtonian mechanics and Newton's second law (F=ma)
  • Basic knowledge of energy forms: potential, kinetic, and thermal energy
  • Concept of interaction energy in physics
NEXT STEPS
  • Research the implications of general relativity on gravitational forces
  • Study the transformation of energy forms in physical systems
  • Explore the concept of pseudo forces in non-inertial reference frames
  • Investigate advanced models of spacetime beyond the trampoline analogy
USEFUL FOR

Students of physics, educators, and anyone interested in the fundamental concepts of gravity and energy transformation in the universe.

shamrock5585
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Gravitational Force!

I have an interesting question... I am hoping its not to easily answerable because it is early in the morning and i may just not be thinking in the right mind.

Energy cannot be created or destroyed...

gravity is just a curve in space-time due to a dent made by an amount of matter.

the analogy is usually that space-time is a trampoline and you put a bowling ball in the middle... small objects put on the trampoline will fall towards the bowling ball. This analogy is pretty good but the reason they fall towards the bowling ball is due to gravity in the first place. if gravity is a curve in space-time then is it really a force? we can describe it as an acceleration on objects but is it really a force technically?

my second question has to do with the first and creation of energy... if we have some small bits of matter just floating in space not moving (no energy) at all which is probably impossible. The small particles will start "falling" towards whatever particle is largest. Now as they start gathering at the larger one it becomes more and more massive which entails more gravity. now as they all start gathering and the gravity increases they start to become compressed and the temperature rises which is an increase in energy... where exactly is this energy coming from?
 
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Regarding your first, question: Good question. Gravity is not considered a force in general relativity. Assuming Newtonian mechanics, you can use Newton's second law (F=ma) in a non-inertial reference frame but you must add pseudo forces (fictional forces) to the external forces on some particle. An interesting fact about these pseudo forces: Such forces are always proportional to mass. Gravity is the only real force in Newtonian mechanics that is proportional to mass. One of Einstein's leaps was seeing that gravity isn't a real force; it is a pseudo force instead.

The second question: Energy comes in several forms. While energy is conserved, it can change form. There is potential energy in the "small bits" of matter separated by some distance. This potential energy is converted to kinetic energy as the particles start moving toward each other, and that kinetic energy is converted into thermal energy as the particles collide and compress.
 
Gravitation

Well gentleman i am not too great in physics and i believe that DH has given the best possible answer, i would like to add some thing to this.Actually answer to second response is itself hidden in your question.
You are saying when matter particles come closer,they become massive.But how is it possible until the particles interact with each other,this is popularly known as interaction energy,which is emitting in form of thermal energy.
If anybody find something wrong in my answer,please let me know,as i have already told that i am not too strong in physics.
With regards.
 
alright thanks, i guess i just have a hard time contemplating potential energy. thanks for the replies guys!
 
To add, the trampoline analogy is somewhat incomplete. Space is 3D not 2D.
 
Daedalus_ said:
To add, the trampoline analogy is somewhat incomplete. Space is 3D not 2D.
And in GR it is 4D spacetime which is curved.
 
true that
 

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