Gravity, cause or effect of time dilation?

In summary, the conversation discusses the relationship between gravity and time dilation. It is suggested that gravity is the effect of time dilation properties of matter. However, it is pointed out that there are two sources of red-shift, one caused by the difference in gravitational potential and the other by cosmic expansion. The question is raised whether gravity could be a way to measure the time dilation properties of matter, but it is noted that both gravity and time dilation may be the effect of some other cause, such as the presence of a large mass. Ultimately, it is concluded that while gravity and time dilation occur together, it does not necessarily mean that one is causing the other.
  • #1
petm1
399
1
With GR saying that gravity is just curved spacetime, wouldn't that make gravity the effect of the time dilation properties of matter?
 
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  • #2
cause.

Regards,

Bill
 
  • #3
What time dilation properties ? It seems you are just renaming gravity ( caused by energy/matter) as 'time dilation property.
 
  • #4
Am I mistaken that all matter is embedded in gravity? I thought that one of the ways that GR was confirmed was the gravitational red shift of a photon, and like the red shift from a distance source we associate it with expansion. The only expansion I associate with matter is in the time dimension as all matter stays the same in the other three dimensions relative to me, which brought me to the question posted above.

This is a wonderful site and I enjoy reading it, I do try to keep my questions to one at a time and not too many per month, and yes I may be calling things by the wrong names but your answers always help me get things right; at least in my own mind. Thanks everyone.
 
  • #5
There are two sources of red-shift. In a famous experiment, Pound and Rebka showed a frequency shift between two points on earth, which is caused by the difference in gravitational potential.

en.wikipedia.org/wiki/Pound-Rebka_experiment

The other red-shift is seen in light coming from distant sources, and is thought to be due to cosmic expansion, as predicted by the Robertson-Walker cosmological metric. There is no way to separate these effects in any observation.
 
  • #6
There is no way to separate these effects in any observation.


Except for the position of the observer, who faces either in or out and will always be able to tell the difference in sources. Matter the embedded part of us with which we measure time appears to be expanding in time, inward, even though we don't see it except as a red shift of a photon. This is the time dilation property of matter. I am asking could gravity be how we measure the time dilation properties of matter, after all time dilation could be one half of the warping to space-time.
 
  • #7
Gravity and time dilation happen together, but that does not mean that one is causing the other. They may both be the effect of some other cause - like the presence of a large mass.
 
  • #8
Mentz114 said:
Gravity and time dilation happen together, but that does not mean that one is causing the other. They may both be the effect of some other cause - like the presence of a large mass.

Yeah - like the presence of a large mass implies gravity, and gravity implies time dilation. :rolleyes:

Regards,

Bill
 
  • #9
I'm sorry, this sounds like a lot of jargon that doesn't amount to anything.

You can get time dilation in one of two ways: going really fast relative to your "fixed" object, or gravity. Both of which end up contracting space-time.

The reason we think gravity makes time-dilation and not the other way around, is because we can manipulate gravity (adding or subtracting mass/energy) but we can't "make" time-dilation and then see mass pop up somewhere. It wouldn't make sense.
 
  • #10
The reason we think gravity makes time-dilation and not the other way around, is because we can manipulate gravity (adding or subtracting mass/energy) but we can't "make" time-dilation and then see mass pop up somewhere. It wouldn't make sense.

We can't "make" gravity nor can we make time dilate, but both of these properties are assoiated with matter. I was just wondering if one was a cause and one an effect or if they could be the same thing.
 
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1. What is time dilation and how is it related to gravity?

Time dilation is a phenomenon in which the passage of time is affected by the presence of gravity. The stronger the gravitational force, the slower time will pass. This is a result of Einstein's theory of general relativity, which states that gravity is not a force between masses, but rather a curvature of space and time caused by the presence of mass. The more massive an object, the more it warps the fabric of space-time, causing time to slow down.

2. How does gravity cause time dilation?

Gravity causes time dilation through the curvature of space-time. As objects with mass move through space, they create a curvature in space-time, much like a bowling ball creates a dip in a trampoline. The more massive the object, the more it warps space-time, causing time to slow down in its vicinity. This effect is also known as gravitational time dilation.

3. Is time dilation the same everywhere in the universe?

No, time dilation can vary depending on the strength of the gravitational field. For example, time moves slower on the surface of Earth than it does on the International Space Station, as Earth's gravitational force is stronger. Additionally, time dilation can also be affected by the speed at which an object is moving, as described by Einstein's theory of special relativity.

4. Can we observe the effects of time dilation in our daily lives?

Yes, we can observe the effects of time dilation in our daily lives, although they may be very small. For example, GPS satellites have to take into account the effects of both special and general relativity in order to accurately provide location and time data. The speed at which they orbit the Earth causes time to slow down ever so slightly, which can affect the accuracy of their clocks.

5. How does time dilation impact our understanding of the universe?

Time dilation plays a crucial role in our understanding of the universe, particularly in relation to the concept of space-time. It has been confirmed through numerous experiments and observations, and has led to advancements in technology such as GPS systems. Time dilation also helps explain some of the mysteries of the universe, such as the behavior of black holes and the expansion of the universe. Without understanding time dilation, our understanding of the universe would be incomplete.

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