Noob question about lorentz factor

In summary: In the first picture, the observer at the rocket will measure the same number of flags as the observer at the spaceport. However, they will disagree about how much time elapses between the flags. There will be 0.1s between flags for one observer and 0.115s between flags for the other. Additionally, the number of flags is different because the observer at the rocket will see them after they've been emitted by the machine on rocket B. However, the observer at the spaceport will see them before they've been emitted.
  • #1
11
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Hello

So i saw this video on youtube explaining some basics of general relativity and they used example with 2 rockets moving paralelly with laser pointed from rocket A to mirror on rocket B.
Heres my picture of it :D
figure1.jpg

Where we are stationary observer watching those two rockets A and B move paralelly.
Here when we consider speed of light as maximal its possible to deduce lorentz factor as factor of speed at which our light beam Y closes from A to B and then back and everything looks fine and works great. But if i try to imagine situation where those two ships do not move paralelly but one after the other.. like on this great picture..
figure2.jpg

Everything just breaks down in my head... let's say velocity of both rockets is c/2 [m/s]
their distance s= c [m] ( one light second)
So i have a few questions and just to be sure I am not making some very bad assumptions, here is what i think must happen :
1] from our (stationary) point of view the light beam will reach ship B in t=2 seconds
2] from our point of view the light beam will reflect back to ship A and reach it in t=2.66 seconds

lets say on ship B is machine which every 0.1 second ejects a signal flag from the ship.
The flag will be green if no light beam hit the mirror and red if ligh beam has allready hit the mirror.
now let's go on board of ship A and beam that light on to them.. now we are 1.9 seconds after beam and they are still pushing out green flags,now they switch, only 7 flags comes out red and then there's our light beam... So what am i missing here ?? I mean the light could not travel different speed on its way back. Also the number of flags may be different due to some time dilatation but i don't think that could hamper the experiment at v= c/2 which is lorentz factor 1.15

Dont bash me pls
Thanks for answers
 

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  • #2
The observer in the rocket will observe the same number of flags as the observer at the spaceport, but they will disagree about how much time elapses between the flags. There will be 0.1s between flags for one observer and 0.115s between flags for the other.
 
  • #3
Ok, but how many of the flags is green ? I mean from the point of rocket A the rocket B is stationary. Yet the number of flags indicate that light travels much longer on its way to rocket B than on its way back. Which is contradiction to general relativity is it not?
 
  • #4
Why don't you give us the link to the video?
 
  • #5
ghwellsjr said:
Why don't you give us the link to the video?

The video doesn't cover this. Its just a scenario i thought about. My issue is that according to general relativity speed of light should be same to all observers. Yet if my example is to be correct there would be evidence on board rocket A that light traveled much slowly on its way to rocket B. And if let's say number of green and red flags had to be same, then from point of stationary observer (ie starbase) machines on rocket B would have to start sending red flags about 0.6 seconds earlier than light could (at light speed observed from that starbase) reach that rocket ... which mean they would have to see 0.6 seconds into the future... which is quite a feat for some fototranzistor.
 
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  • #7
You have to be real careful about who is measuring what.
 

1. What is the Lorentz factor?

The Lorentz factor is a mathematical term used in the theory of special relativity to describe the relationship between an object's velocity and its measured length and time. It is represented by the symbol gamma (γ) and is calculated as 1/√(1 - v^2/c^2), where v is the velocity of the object and c is the speed of light.

2. How is the Lorentz factor related to time dilation and length contraction?

The Lorentz factor is directly related to both time dilation and length contraction, which are two fundamental principles of special relativity. Time dilation refers to the fact that time appears to pass slower for an object moving at high speeds relative to an observer, while length contraction refers to the shortening of an object's length in the direction of its motion. The Lorentz factor is used to calculate the amount of time dilation and length contraction experienced by an object at a given velocity.

3. Why is the Lorentz factor important in physics?

The Lorentz factor is important in physics because it helps to explain the observed effects of time dilation and length contraction at high speeds. It also plays a crucial role in many other equations and principles of special relativity, such as the famous equation E=mc^2. Additionally, the Lorentz factor is essential in understanding the behavior of particles at high speeds, such as in particle accelerators.

4. How does the Lorentz factor affect an object's mass?

The Lorentz factor does not directly affect an object's mass. However, as an object's velocity approaches the speed of light, its Lorentz factor increases, and as a result, its mass appears to increase as well. This phenomenon is known as relativistic mass and is one of the key principles of special relativity.

5. Can the Lorentz factor be greater than 1?

Yes, the Lorentz factor can be greater than 1 for objects moving at speeds close to the speed of light. In fact, as an object's velocity approaches the speed of light, its Lorentz factor approaches infinity. This means that at the speed of light, the Lorentz factor becomes undefined, and the principles of special relativity no longer apply.

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