Relativistic Effects on CMB and Cosmic Rays

[qraal]

Imagine moving at relativistic speeds. The moving object sees the Cosmic Microwave Background blueshift and become moved into the forward field of view due to aberration. Of course the hemisphere behind becomes even darker due to red-shift, while the forward hemisphere contracts towards a point. My question is: once the object is moving fast enough for the CMB to become visible, then what is the flux observed coming from the forward direction? And is it concentrated into a 'beam' by aberration or merely visible as a central point in the forward direction of all co-moving observers?

 

[DaveC426913]

Is this about what one observes as one approaches relativistic velocities? Or is it about the CMB? I'm having trouble understandfing why you are relating these two phenomena.

 

[qraal]

Is this about what one observes as one approaches relativistic velocities? Or is it about the CMB? I'm having trouble understandfing why you are relating these two phenomena.

The CMB at extreme levels of relativistic aberration and blue-shift.

 

[DaveC426913]

The CMB at extreme levels of relativistic aberration and blue-shift.

OK well, there's all sorts of radiation out there that's not CMB. They will undergo the same effect.

 

[qraal]

OK well, there's all sorts of radiation out there that's not CMB. They will undergo the same effect.

Indeed. Above a certain gamma-factor the cosmic rays "from behind", the rear hemisphere, will be absorbed by the front shields.