Universe

[applesauce]

[1411.3987] Photons that travel in free space slower than the speed of light

this is the actual paper

 

[Malik Alashter]

One example which I have already cited in the thread is the law of galilean relativity. It fails to explain the postulates of special theory of relativity.

I thought we are talking about laws of phisics these laws sir are not breakable period a law that is breakable that is theory.

 

[Providence]

I thought we are talking about laws of phisics these laws sir are not breakable period a law that is breakable that is theory.

Kindly go back and read what I have written about the difference between a law and theory. Law is called a law since it holds true in varied circumstances. Why would you want to change or improve a law is beyond me.

 

[Mythal]

None taken.

First let us get the usual stuffs out of the way. When I said an object travelling at speed of light, obviously it was hypothetical but the intention was to highlight the relativistic effects of speed.

Secondly, when you are talking about time, pertinent question is not to comment about time but to ask whose perception of time. Both will differ. The object A from his reference will see his time to be traversing normally but object B's time to have virtually stopped. The reverse would be the case with object B's frame of reference.

While for a third observer say standing on earth, would see the time to have stopped for both the objects from his reference.

Thirdly, doppler's effect has nothing to do with speed (c) but shift in the frequency (v). As the frequency changes, so would the wavelength (λ)

Speed will always be constant and c = v * λ will hold true always.

Aye? Doppler's effect is the shift in frequency but because of a moving object so it does have everything with speed (velocity to be precise). Isnt doppler effect the method used to calculate how fast a celestrial object is moving towards us or away from us. Same with the speed guns.

 

[Hamartia Antidote]

Astronomers compile stunning 46-billion pixel image of the Milky Way

http://astro.vm.rub.de/

 

[Providence]

Aye? Doppler's effect is the shift in frequency but because of a moving object so it does have everything with speed (velocity to be precise). Isnt doppler effect the method used to calculate how fast a celestrial object is moving towards us or away from us. Same with the speed guns.

You are right. I should not have said, "doppler effect has nothing to do speed". Thanks for correcting me but could you elaborate your contention and vis-a-vi the corresponding claim which I made ?

 

[Mythal]

You are right. I should not have said, "doppler effect has nothing to do speed". Thanks for correcting me but could you elaborate your contention and vis-a-vi the corresponding claim which I made ?

None taken.

First let us get the usual stuffs out of the way. When I said an object travelling at speed of light, obviously it was hypothetical but the intention was to highlight the relativistic effects of speed.

Agreed completely.

Secondly, when you are talking about time, pertinent question is not to comment about time but to ask whose perception of time. Both will differ. The object A from his reference will see his time to be traversing normally but object B's time to have virtually stopped. The reverse would be the case with object B's frame of reference.

This is somewhat of a problem. For an object travelling at the speed of light, there would be no perception of time at all.
Refer to this video i shared earlier, astronomy or physics was not my field of study, these things are mostly self taught for me, so may be I am understanding something wrong or this video is getting something wrong.

While for a third observer say standing on earth, would see the time to have stopped for both the objects from his reference.

Agree with this part.

 

[Providence]

This is somewhat of a problem. For an object travelling at the speed of light, there would be no perception of time at all.
Refer to this video i shared earlier, astronomy or physics was not my field of study, these things are mostly self taught for me, so may be I am understanding something wrong or this video is getting something wrong.

Read again what I have written. When you say there won't be any perception of time, which frame are you referring to again ? From Object A's frame or Stationary frame ?

Your video's intro is vague. 0.38 when he says NO ANSWER, that's wrong but what they say 2.01 forward about the perception of light is correct.

 

[Mythal]

Read again what I have written. When you say there won't be any perception of time, which frame are you referring to again ? From Object A's frame or Stationary frame ?

Your video's intro is vague. 0.38 when he says NO ANSWER, that's wrong but what they say 2.01 forward about the perception of light is correct.

Even from Object A's frame, the one who is travelling at the speed of light.
Refer to the part of the video about a massless vehicle at the speed of light starting at 6:05

 

[Providence]

Even from Object A's frame, the one who is travelling at the speed of light.
Refer to the part of the video about a massless vehicle at the speed of light starting at 6:05

Boy !! I hate that Vsauce guy

Let me watch that video again though

 

[Providence]

Even from Object A's frame, the one who is travelling at the speed of light.
Refer to the part of the video about a massless vehicle at the speed of light starting at 6:05

Okay. This is what Einstein exactly says, "All inertial frames are same" meaning if you are not accelerating and moving at uniform speeds, your impression of light should be same as the special inertial frame which is at rest. Consequently, what Object A can say is, the "stationary" object is the one moving at 'c' in opp direction and he is at rest and so is object B.

So, I believe Object A will still see light travelling at 'c' towards B.

I am open to correction though.

@Spectre @applesauce your comments please




EDIT: @mithyaa I have gone through your full video twice. Some of the things which the guy says is either wrong or he is liberally using some terms which he shouldn't.

E.g. the fella says that there won't be a concept of time when you are travelling at 'c'. He completely missed mentioning w.r.t. outside/surrounding frame of reference. In his frame, he could see clock ticking normally.

 

[Marshmallow]

Nice Thread ...and Informative too ...Thanks

 

[Providence]

@mithyaa

Let's consider your earlier assertion. Suppose you are riding a beam towards a rotating planet like Saturn from the SUN. If suppose time would have meant nothing to you and if you would have launched in the direction of saturn, you would have reached saturn in time zero.

Consider a lowly amateur astronomer like me observing the beam in space. I would notice that in 75 light minutes, saturn would have moved from it's original position and moved along it's orbital curvature by a significant distance to have missed that beam. But you (riding the beam ) will see yourself reaching saturn in time zero.

Both can obviously not happen. Such bizarre results are coming because you are treating the perception of time to be same in all frames.

@Kashmiri Pandit Check this video

 

[Kashmiri Pandit]

@Kashmiri Pandit @mithyaa

Check this video

At 5.00

When Space Ship is close to speed of light , Time inside slows down .
But Adam feels time moving normally .
To the outside observer , is it slow , fast or normal ???

Are observer and Adam affected by time equally ???

Ahhhhh !!! I am getting confused . My physics score in college were 36 . So teach me like a newbie .

Around 12:00
During acceleration , Adam is pushed back but to him ship is not moving but Universe is moving .
Explain ???

Is it some thing like when we move in a car and look at Moon , It feels like moon is moving but in reality its us who are moving

After 13:30
When Adam returns
Observer was old but for him only a small amount of time has passed .( If time is flowing normally for him inside the ship , then how come he didn't age )
This is what has confused me for a long time .

One more thing
Lets say planet A and Planet B were born on the same time .
Planet A = Earth
Planet B = Mars

From that day till now 4.5 billion years ( Time ) has passed .
Mars which is smaller , has less gravity etc . Does it has spend the same 4.5 billion years or more/less .
Will the time clock and biological Clock be affected if say humans were also living on Mars .

Will there be any change ,
Say Person A traveled to Mars . It took him 1 year . He left soon after the touch down , which took him 1 more year . 2 years spent . Will we see changes in him and those on Earth .
If this travel carried over a long distance , will the affects be more prominent ????

Do we call this time Travel .
Like going in past or future . Like time slices from Illusion of time .

Astronomers Discover 252 Ultra-Faint Dwarf Galaxies in Early Universe

 

[Providence]

At 5.00

When Space Ship is close to speed of light , Time inside slows down .
But Adam feels time moving normally .
To the outside observer , is it slow , fast or normal ???

Are observer and Adam affected by time equally ???

Ahhhhh !!! I am getting confused . My physics score in college were 36 . So teach me like a newbie .

Around 12:00
During acceleration , Adam is pushed back but to him ship is not moving but Universe is moving .
Explain ???

Is it some thing like when we move in a car and look at Moon , It feels like moon is moving but in reality its us who are moving

As for the first part, (5:00+) Adam who is travelling at 'c' will feel no change in his clock but Sara who is stationary will see Adam's clock to slow down. So, Adam's perception of his time and Sara's perception of Adam's time would differ. Now this was from Sara's perspective. If you start to think from Adam's perspective, opposite would be the case.

I hope it should be clear by now

(12:00+) This is because Adam's perception of him was, he was at rest before he fired his rockets. So, it's the Universe which is accelerating in the opposite direction because of the "gravitational force". And since the rocket still didn't move, that means rocket balanced this sudden gravitational force which effected the rest of the universe.

Is it fine ?