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Q & A: Is the universe spinning?

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Most recent answer: 04/25/2014
Q:
If the universe rotates this could explain several questions if it spins and gravity is the effect of rotation instead of fundamental that's why it's so weak so rotation=pulling and the explosion of the singularity is the pushing then if the rotation slows the expansion would speed up thinking of space as water in a glass drop in salt it doesn't ecrete until you spin the glass the everything clumps together your thoughts and knowledge
- Preston Markham (age 35)
lake city fl us
A:

Hello Preston,

That hypotheses doesn't work for many reasons.  If it were true then the force of gravity would always point in the direction of the universe spin axis.  No such preferred axis has been observed.  The Hubble expansion rate seems to be uniform in all directions.   Another example is that the force of gravity on the moon always is aligned along the earth-moon axis, always moving with respect to a preferred axis.   In addition there would be a 1/r2 dependence from the supposed 'center of the universe'... again, not observed.

 

LeeH

 

 


(published on 04/18/2014)

Follow-Up #1: how long to see stars?

Q:
If the light we see from stars travels for years before it reaches us is it safe to say we don't see the present time for years to come
- Preston Markham (age 35)
lake city fl us
A:

It's a little tricky to say what we mean by "the present time" because there are a range of perfectly good coordinate systems which pair up our "now" with different "simultaneous" events on a distant star. However, at least if we stick to the coordinate systems of special relativity, all of these do have a delay of years before light from the "now" event at the distant star reaches us. In fact, the system with the shortest delay is the one in which we and the star (which I assume isn't moving much with respect to us) are at rest. So yes, we don't see the star's present time for years.

Mike W.


(published on 04/23/2014)

Follow-Up #2: Where does all the energy go?

Q:
If energy never dies what happens to it once it's so diluted it can't be"accessed"does it continue to flow along silently into the vastness of space. Like if you were in space and you turned on a flash light and then turned it off the light is gone but all the energy from the light is still there right we cud never detect it probably but all that energy is still present doing something right whats it doing
- Preston Markham (age 35)
lake city fl us
A:

You're right- it just keeps going off into the vastness of space. Space is full of things like tht- the cosmic microwave background, bits of starlight. Some of it may at some point hit some ordinary matter and be absorbed, heating the matter up a little.

Mike W.


(published on 04/25/2014)

Follow-up on this answer.