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On the Lighter Side => New Theories => Topic started by: pasala on 30/03/2018 18:11:03

Title: Gravity as a curved spacetime
Post by: pasala on 30/03/2018 18:11:03
Friends,
Here I am placing few questions for general discussion and not for any criticism.

Gravity as Curved Spacetime:

Einstein eventually identified the property of spacetime which is responsible for gravity as its curvature. Space and time in Einstein's universe are no longer flat but can be pushed and pulled, stretched and warped by matter. Gravity feels strongest where spacetime is most curved, and it vanishes where spacetime is flat. This is the core of Einstein's theory of general relativity, which is often summed up in words as follows: "matter tells spacetime how to curve, and curved spacetime tells matter how to move".

Since gravity is more on Earth when compared to Moon:

01  Why spacetime is more curved near the Earth
02  Why don’t it near Moon
03  Why matter pulls, stretches and warps Spacetime near Earth only
04  Why don’t it near Moon.
05  Do matter which is capable of bending spacetime exist near Earth only

Einstein Field equations are different, and simply it is a mathematical description of spacetime.  If Gravity is due to spacetime than it must be equal or spread in Horizontal or vertical directions.  It is surprise, why spacetime is flat on moon and some of the planets and at the same time it is curved against Earth and some other Planets.  why don’t it change from  time to time.

Yours
Psreddy
Title: Re: Gravity as a curved spacetime
Post by: Kryptid on 30/03/2018 21:10:48
Whoever said that space-time isn't curved near the Moon?
Title: Re: Gravity as a curved spacetime
Post by: pasala on 31/03/2018 03:32:33
Ok, kryptid
When spacetime is responsible for Gravity, why it is weak or bent slightly against Moon.  What made it to be strong against Earth or more curved.  Please see, it is the curvature or spacetime.  Science developed a lot and we are not in 20th Century.  Gravity changes from planet to planet according to local conditions.  If the Spacetime is responsible for Gravity than it must be equal on all planets, instead.

Yours
Psreddy
Title: Re: Gravity as a curved spacetime
Post by: Kryptid on 31/03/2018 04:24:52
The Earth has much more mass than the Moon does.
Title: Re: Gravity as a curved spacetime
Post by: jeffreyH on 31/03/2018 14:25:14
Let's say we have two masses m0 for the earth and m1 for the moon. Then m0 does not equal m1. Since the gravitational potential is Gm/r then at an identical radial distance from either source, the earth or the moon, we will obtain potentials that depend upon radial distance and mass. These will be different for each object. Showing that the curvature depends upon the amount of mass. If you argue against this then you show yourself to be ignorant of all scientific observations on the matter. In which case you should be listening to the wisdom of others.
Title: Re: Gravity as a curved spacetime
Post by: pasala on 01/04/2018 18:15:31
It is true that attraction between two masses is far limited and that too when they comes near to each other.  As predicted by Einstein it is something else that is playing key role in Gravity.  Here it is wonder, how can we compare Gravity of Earth to Gravity of Moon.  Since Moon lost most of its Gravity it has fallen to the Gravity of Earth and rotating against the Gravity of Earth.   It is the only planet where human beings landed.

Here we have to remember some of the important facts that if the Gravity of any planet whether it is small or big is high than it will be more responsive to Sun Gravity and start rotating with maximum speed. In case if the Gravity of a planet is weak, Sun rays have to use more force to rotate the Planet.  Obviously if the Gravity is strong, Gravity rays moving from the Planet interacts with Sun rays easily and even simple push makes the planet to rotate. 

Here Mass is a negative feature.  The more mass a planet is having means it needs more gravity to sustain in its place as a planet and to rotate. 

As long as any planet maintains sufficient Gravity, it maintains its individuality as a Planet.  Here size of Planet is immaterial, but a planet having more mass loses Gravity quickly than a small planet.  One’s the planet loses Gravity it start moving away.  In case if any planet is having strong Gravity than even big planets turns out as sub-planets.

We are simply calculating Gravity using Newton’s “Universal law of Gravitation” which is not so correct. 

Yours
Psreddy
Title: Re: Gravity as a curved spacetime
Post by: guest39538 on 01/04/2018 20:31:54
Let's say we have two masses m0 for the earth and m1 for the moon. Then m0 does not equal m1. Since the gravitational potential is Gm/r then at an identical radial distance from either source, the earth or the moon, we will obtain potentials that depend upon radial distance and mass. These will be different for each object. Showing that the curvature depends upon the amount of mass. If you argue against this then you show yourself to be ignorant of all scientific observations on the matter. In which case you should be listening to the wisdom of others.
It is my understanding that there is no gravity curvature , the object in orbit is travelling a linear path but forced to follow a curved path by the force of G to retain an equal radius from the sphere?

The curve created relative to a constant velocity while gravity retains its linear hold.


* speed.jpg (20.13 kB . 740x464 - viewed 2985 times)

Title: Re: Gravity as a curved spacetime
Post by: Colin2B on 01/04/2018 22:36:52
Sun rays have to use more force to rotate the Planet.  Obviously if the Gravity is strong, Gravity rays moving from the Planet interacts with Sun rays easily and even simple push makes the planet to rotate. 
The sun’s rays do not cause a planet to rotate.

We are simply calculating Gravity using Newton’s “Universal law of Gravitation” which is not so correct. 
In what way do you think it is incorrect? What experimental evidence do you have?

but a planet having more mass loses Gravity quickly than a small planet.
How do you think it loses mass?
Title: Re: Gravity as a curved spacetime
Post by: jeffreyH on 01/04/2018 23:09:40
Let's say we have two masses m0 for the earth and m1 for the moon. Then m0 does not equal m1. Since the gravitational potential is Gm/r then at an identical radial distance from either source, the earth or the moon, we will obtain potentials that depend upon radial distance and mass. These will be different for each object. Showing that the curvature depends upon the amount of mass. If you argue against this then you show yourself to be ignorant of all scientific observations on the matter. In which case you should be listening to the wisdom of others.
It is my understanding that there is no gravity curvature , the object in orbit is travelling a linear path but forced to follow a curved path by the force of G to retain an equal radius from the sphere?

The curve created relative to a constant velocity while gravity retains its linear hold.


* speed.jpg (20.13 kB . 740x464 - viewed 2985 times)



So how would you describe the path it is following? What about the dilation of time at different radial distances from the source? Do you actually understand what curvature means in these circumstances?
Title: Re: Gravity as a curved spacetime
Post by: guest39538 on 01/04/2018 23:50:17
Let's say we have two masses m0 for the earth and m1 for the moon. Then m0 does not equal m1. Since the gravitational potential is Gm/r then at an identical radial distance from either source, the earth or the moon, we will obtain potentials that depend upon radial distance and mass. These will be different for each object. Showing that the curvature depends upon the amount of mass. If you argue against this then you show yourself to be ignorant of all scientific observations on the matter. In which case you should be listening to the wisdom of others.
It is my understanding that there is no gravity curvature , the object in orbit is travelling a linear path but forced to follow a curved path by the force of G to retain an equal radius from the sphere?

The curve created relative to a constant velocity while gravity retains its linear hold.


* speed.jpg (20.13 kB . 740x464 - viewed 2985 times)



So how would you describe the path it is following? What about the dilation of time at different radial distances from the source? Do you actually understand what curvature means in these circumstances?
I would describe the path it is following as circular radius points  where the gravity force is equal at all points . A lessened state of strength because of the inverse square law where a constant speed counter acts  the force.   

Time dilation I assume is something to do with less field density at altitude.

Do I know what curvature is ?  An orbital path that resembles a curve shape, an imaginary line that is curved. 

Not sure....:D
Title: Re: Gravity as a curved spacetime
Post by: pasala on 08/04/2018 15:13:40
Mr Colin2B

You had number of questions.  If Newton's "Inverse square law" is 00% correct than why Einstein's relativity.  When the objects are near to each other, its ok but here it is several millions of kilometers and what attraction is keeping them in a particular line is big question. 

Ok, coming out from this, let us start about curved space time.  It is true that particles are raising.  As per our knowledge goes most of them are water particles only.  Where these particles are concentrating.  Do these particles crossing climate.  As per Einstein, matter is curving the space time and Gravity is due to this curvature only. 

As per my knowledge goes:
In physics, space time is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum.

Here, Space time diagrams are useful in visualizing and understanding relativistic effects such as how different observers perceive where and when events occur.

Basic question, in fact not about mathematical model, 2d Space time or 4d Space time but how the space time is curved.

Mathematical model simply describes about space time and it never tells what exactly space fabric consists of.  A fabric is different, space is different and if it has to work like a fabric than there must be an obstruction that keeps the things in a specific line.  A particle raising from the Earth either due to velocity or whatever reason it may, if it has to stop at a particular place, it won’t by itself.  There must be something, and description about which, I don’t think so.

Einstein’s space time is highly useful for visualizing things that are happening in different places and it is relativity comparison only.

Even now, formation of 2d and 4d space time is big question, how it changes from planet to planet.  What exactly space time consists of and how it is being curved by the matter.
 

Yours
Psreddy