Do we have time because we are moving?

  • Thread starter Taragond
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In summary: I chose the center of the kosmos and assume, there won't be any gravitation left because it all flew out into space (which is still accellerating it's expansion afaik)If we would take two perfectly synchronised clocks measuring time from 0 to infinity and put one on earch and one at the center of our universe assuming there it has the absolute speed and gravitational pull of zero each. How much would the measured time differ between these within an hour/day/week/month/year/ (earth time)... PS: I searched for those numbers, please feel free to replace them with more likely values if I didn't chose well. personally i guess we can't
  • #71
Taragond said:
maybe that's what I am trying to do...

If I had 2 synchronized clocks A&B and send B away with.9c for one year after which it decellerates and flies back. would the clocks still be synchronized? As I understand it, B would show less time has passed?

If that's correct, I would expect that in C time runs slower than in B, but from A's perspective in C time runs less slow than in B...so no...probably not...
But if it is a measurable effect with clocks there must be a solution to this?

I guess it would be too much to clarify here why speeds don't add algebraically? not sure, what to search for...
Of course there's a solution for any problem that's consistently and completely described but you have combined parameters that are inconsistent and left out other important details so that there is not a single interpretation of your scenario.

You could have said:

3 synchronized clocks, one stays at A while two are sent with B at .6c away from A.
After one year according to B's time, C gets with one of those clocks on B in a lifeboat and heads at .9c away from B relative to B in direction of A.

Then you could ask your questions like how fast is C traveling in A's rest frame and what time is on each clock in the different rest frames.
 
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  • #72
ghwellsjr said:
You could have said:

3 synchronized clocks, one stays at A while two are sent with B at .6c away from A.
After one year according to B's time, C gets with one of those clocks on B in a lifeboat and heads at .9c away from B relative to B in direction of A.

Then you could ask your questions like how fast is C traveling in A's rest frame and what time is on each clock in the different rest frames.
well...that one! :-p

I am really sorry for my lack of precision in my questions. Maybe it's because english is not my native language, maybe lack of experience in discussions on these matters. Probably a bit of both...

But what does happen if you remove the difference in rest-frames by decellerating before comparing the clocks?
 
  • #73
Taragond said:
ghwellsjr said:
You could have said:

3 synchronized clocks, one stays at A while two are sent with B at .6c away from A.
After one year according to B's time, C gets with one of those clocks on B in a lifeboat and heads at .9c away from B relative to B in direction of A.

Then you could ask your questions like how fast is C traveling in A's rest frame and what time is on each clock in the different rest frames.
well...that one! :-p
Ok, I'm going to do it from the Inertial Reference Frame (IRF) of the B clock after it leaves the A clock at 0.6c because then I can simply specify the speed of the C clock after 1 year to be -0.9c according to the same IRF. I have made a spacetime diagram showing all the timings you asked about. Note that the dots mark off one-month intervals of Proper Time along each of the three clocks' worldlines. I have marked in some of the Proper Time values to help you determine the intervening ones. I have also annotated significant events along the way. Start at the bottom of the diagram and work your way up:

Taragond60.PNG

In the above diagram, there are three significant speeds:

1) All three clocks start out at -0.6c with synchronized clocks up until time zero. The A clock (blue) continues on an inertial path.

2) The B clock (red) along with the C clock accelerates to 0.6c with respect to the A clock so it comes to rest in the IRF that I am calling B's IRF (even though it is only B's IRF after time zero).

3) At B's Proper Time (which is also the Coordinate Time) of twelve months, C accelerates away from B at -0.9c toward A.

I have also annotated the Proper Times along each of the worldlines corresponding to the 1-, 2- and 3-year intervals of Coordinante Time as you requested.

Does that make perfect sense to you?

Now you were also interested in the speed of C relative to A. You had said that it would be 0.3c since C originally departed away form A at 0.6c and then returned at 0.9c. But a simple algebraic solution doesn't work. Instead, we can see the answer by using the Lorentz Transformation on the Coordinates of all the events (dots) in the original diagram to create a new diagram moving at -0.6c with respect to the first one. This now becomes the IRF in which the A clock (blue) is at rest:

Taragond61.PNG

We can see that the speed of the C clock (black) as it is approaching the A clock (blue) is about -0.65c. Do you know how to determine this speed from the diagram? We can also determine this speed exactly using the relativistic velocity addition formula with v=0.6 and u=-0.9:

s = (v + u)/(1 + vu) = (0.6-0.9)/(1 + (0.6)(-0.9)) = -0.3/(1-0.54) = -0.3/0.46 = -0.652

I have also marked in the Proper Times along each of the clocks' worldlines corresponding to the 1-, 2-, and 3-year intervals of Coordinate Times as per your request. Note that these Proper Times are completely different than those that were determined according to the first IRF.

Even though the Proper Times at which the Coordinate Times are different in the two IRF's, the Proper Times at which identifiable events occur along the worldlines are the same in both IRF's. For example in both diagrams:

1) the last Proper Times at which all three clocks are together is 0.

2) the Proper Times on clocks B (red) and C (black) when they separate is 12 months.

3) the Proper Times on clocks A (blue) and C (black) when they pass each other is 28.8 months for clock A and 22.46 for clock C.

Taragond said:
I am really sorry for my lack of precision in my questions. Maybe it's because english is not my native language, maybe lack of experience in discussions on these matters. Probably a bit of both...

But what does happen if you remove the difference in rest-frames by decellerating before comparing the clocks?
Here's another example of lack of precision: are you wanting the C clock to decelerate to the same speed as the A clock when they reunite? But then what about the B clock? It just keeps on going away from the A clock. When do you want it to decelerate and to what speed in which IRF do you want this to happen?
 
<h2>1. How does our movement affect the concept of time?</h2><p>Our movement does not directly affect the concept of time. Time is a constant and it is not influenced by our movement. However, our perception of time may be affected by our movement, as we may perceive time to be passing faster or slower depending on our speed and surroundings.</p><h2>2. Does time move differently for objects that are in motion?</h2><p>According to Einstein's theory of relativity, time can be affected by an object's speed and gravitational pull. However, these effects are only noticeable at extremely high speeds or in the presence of strong gravitational forces. For everyday objects and movements, time moves at a constant rate.</p><h2>3. Can we travel through time by moving at high speeds?</h2><p>While it is possible to travel through time in theory, it is not possible with our current technology and understanding of physics. Moving at high speeds can cause time dilation, where time appears to move slower for the moving object, but it does not allow for time travel in the traditional sense.</p><h2>4. How does time dilation work in relation to our movement?</h2><p>Time dilation occurs when an object is moving at high speeds, causing time to appear to move slower for that object. This is due to the fact that the faster an object moves, the more it warps the fabric of space-time, causing time to slow down for that object relative to a stationary observer.</p><h2>5. Does our perception of time change when we are in motion?</h2><p>Yes, our perception of time can change when we are in motion. This is due to the fact that our brains process information differently when our bodies are in motion, which can make time appear to pass faster or slower. Additionally, our surroundings and the speed at which we are moving can also affect our perception of time.</p>

1. How does our movement affect the concept of time?

Our movement does not directly affect the concept of time. Time is a constant and it is not influenced by our movement. However, our perception of time may be affected by our movement, as we may perceive time to be passing faster or slower depending on our speed and surroundings.

2. Does time move differently for objects that are in motion?

According to Einstein's theory of relativity, time can be affected by an object's speed and gravitational pull. However, these effects are only noticeable at extremely high speeds or in the presence of strong gravitational forces. For everyday objects and movements, time moves at a constant rate.

3. Can we travel through time by moving at high speeds?

While it is possible to travel through time in theory, it is not possible with our current technology and understanding of physics. Moving at high speeds can cause time dilation, where time appears to move slower for the moving object, but it does not allow for time travel in the traditional sense.

4. How does time dilation work in relation to our movement?

Time dilation occurs when an object is moving at high speeds, causing time to appear to move slower for that object. This is due to the fact that the faster an object moves, the more it warps the fabric of space-time, causing time to slow down for that object relative to a stationary observer.

5. Does our perception of time change when we are in motion?

Yes, our perception of time can change when we are in motion. This is due to the fact that our brains process information differently when our bodies are in motion, which can make time appear to pass faster or slower. Additionally, our surroundings and the speed at which we are moving can also affect our perception of time.

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