-1
votes
1answer
50 views

Reference frames and speed of light

If the speed of light is a constant, and the universe is expanding, wouldn't shining a light in the direction of the center of the universe have a different color (frequency and wave length) than ...
0
votes
1answer
51 views

What would be the speed of a hypothethetical object created during the big bang

What would be the speed of a hypothethetical object created during the big bang, and that has been moving around in the universe and that is now close to the earth, so the time elapsed (from the ...
0
votes
0answers
54 views

What is the age of the Universe from the big-bang light perspective?

What is the age of the Universe from the big-bang light perspective? We all agree that the universe is around 14 billion years, from the perspective of a hypothetical observer moving in a galaxy, ...
-1
votes
1answer
101 views

If the universe can expand at a speed faster than that of light, why don't we feel the effect? [closed]

the universe, as I have read, is capable of inflating at a speed faster than that of light! How is that even possible if we don't feel the effect? or does it affect us?
-1
votes
0answers
92 views

Are we travelling at a speed close to the light speed? [duplicate]

This is a question which has been puzzling me quite a while. There was a news report saying that the farthest galaxy spotted so far is at 13.3 billion light-years away, and it is said that the galaxy ...
2
votes
5answers
449 views

Is there a universal rest frame of reference?

I am still struggling with C being a constant and what that implies. So can an experiment be done to find the resting state for the universe? Take a device with an observer and a light source and two ...
6
votes
3answers
807 views

At what speed does our universe expand?

Conceivably it expands with the speed of light. I do not know, but curious, if there is an answer. At what velocity, does our universe expand?
6
votes
6answers
1k views

What are the most realistic ways of high speed space propulsion?

Liquid and solid chemical fuels in rockets are very expensive and inefficient. I have heard of solar sails but what are the most realistic space travel fuels that will be used in the future to get ...