Time dilation and gravitational constant

In summary, gravitational constant is a dimensionfull constant that is affected by gravitation and causes gravitational time dilation. This means that the definition of a second is only valid locally and not globally. In the geometrized unit system, the gravitational constant is simplified to a value of 1. In general relativity, using a distant clock to measure physical processes in a gravity well will result in different values for constants due to the effects of gravitational time dilation.
  • #1
zonde
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I have a question about gravitational constant.
Gravitational constant is dimensionfull constant but say time is is affected by gravitation causing gravitational time dilation. So the definition of second is local.
Does it means that gravitational constant is well defined locally but not globally?
How this is treated in GR?
 
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  • #2
zonde said:
Gravitational constant is dimensionfull
Not in the http://en.wikipedia.org/wiki/Geometrized_unit_system" , where it is just 1.
zonde said:
constant but say time is is affected by gravitation causing gravitational time dilation. So the definition of second is local. Does it means that gravitational constant is well defined locally but not globally?
If you use a distant clock to measure some physical processes in a gravity well, you will come up with different values for constants, because everything is slowed down.
 
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  • #3


Time dilation and gravitational constant are both important concepts in the theory of general relativity (GR). Time dilation refers to the phenomenon in which time appears to pass at a different rate for two observers in different gravitational fields. This is due to the curvature of spacetime caused by massive objects. Gravitational constant, on the other hand, is a fundamental constant in physics that determines the strength of the gravitational force between two objects.

To answer your question, in GR, the gravitational constant is considered to be a fundamental constant that is well-defined globally. This means that it has the same value in all regions of spacetime, regardless of the strength of the gravitational field. However, as you mentioned, time dilation does affect the measurement of time, which is why the definition of a second is considered to be local. This means that the length of a second can vary in different gravitational fields.

In GR, the effects of time dilation and the value of the gravitational constant are both taken into account when making calculations and predictions. The theory allows for the gravitational constant to be a fixed value globally, while also allowing for variations in the measurement of time due to gravitational effects. This allows for a consistent and accurate understanding of the universe at both local and global levels.

In summary, while time dilation and the gravitational constant may seem to contradict each other, they are both important concepts in GR that are accounted for in calculations and observations. The gravitational constant is considered to be a well-defined constant globally, while the measurement of time can vary locally due to the effects of gravity.
 

Related to Time dilation and gravitational constant

1. What is time dilation?

Time dilation refers to the phenomenon where time passes at different rates for objects that are moving at different speeds or are in different gravitational fields.

2. How does time dilation occur?

Time dilation occurs due to Einstein's theory of relativity, which states that the laws of physics are the same for all observers in uniform motion. This means that time can appear to pass differently for different observers depending on their relative speeds or gravitational fields.

3. What is the formula for time dilation?

The formula for time dilation is t' = t / √(1 - v²/c²), where t' is the observed time, t is the proper time, v is the velocity of the object, and c is the speed of light.

4. How does the gravitational constant affect time dilation?

The gravitational constant, represented by G, determines the strength of the gravitational force between objects. The stronger the gravitational force, the greater the time dilation will be. This means that time will pass slower in stronger gravitational fields, such as near massive objects like planets or stars.

5. Can time dilation be observed in everyday life?

Yes, time dilation can be observed in everyday life, although the effects are very small. For example, GPS satellites have to account for time dilation due to their high speeds and distance from Earth's gravitational field in order to accurately calculate location and time for navigation purposes. Also, astronauts experience time dilation during space travel at high speeds, which can result in them aging slightly slower than people on Earth.

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