Does measuring the age of the universe result in objective observation?

In summary: The age of the universe as measured by the microwave background radiation. * The age of the universe as measured by the light from quasars.In summary, Matt asked if the conventional terminology of "no center of the universe" means that there is no point from which one can measure the universe's diameter, and if so, how would other observers make corrections. He also asked about other ways to measure the age of the universe. According to the author, all of these methods result in a universe that is estimated to be around 13.2 billion years old.
  • #1
MattAndMatthe
7
0
Let me know if there are any errors or holes in my logic, facts, or assumptions.

I was thinking in regards to time being relative to the observer and the resulting impossibility of an objective measure of time: In determining the age of the universe, our current estimation is about 13.2 billion years. Now, this would be an estimate or measure based on our earthly frame of reference, the universe being 13.2 billion years old as observed by earthlings.

But since any point in the universe can be considered its center, then the 13.2by estimation would result as observed from any other frame of reference in the universe. Therefore, the measure of the age of the earth, as measured in units of time, according to the CMBR is objective and not relative to any frame of reference since every frame of reference is the same.

Also, wouldn't this apply to the estimation of the "diameter" of the universe in light years?
 
Physics news on Phys.org
  • #2
It's certainly true that certain observers could have had world-lines that started shortly after the big bang and yet have accumulated a lot less than 13 billion years worth of proper time.

The thing you have to realize about cosmological solutions is that they generally have preferred frames of reference. These preferred frames are not provided by the laws of physics (as in aether theories) but by the matter and radiation that are present in the universe. In our universe, the preferred frame is the frame in which the average momentum of the CMB vanishes. The solar system is not at rest relative to this frame, as demonstrated by the dipole component of the CMB.

Any time you have a preferred frame of reference, you also get a preferred time coordinate, which is the proper time measured by observers at rest in the preferred frame. In our universe, this time coordinate is interpreted as the time you can measure by looking out the window and seeing the present conditions of the universe (how hot, how dense, etc.). It's according to this time coordinate that the universe has the 13-billion-year age.
 
  • #3
Hi Matt...good questions, not easy conceptsto understand at first.
conventional terminology says there is no center of the universe...so its not good to say "any point is its center" because there is no such point, no even one...no one knows the diameter of the universe...we can only observe as far a light (radiation) has had time to reach us...after the dense ionized gas following the big bang formed atoms and radiation could get thru...how much things expanded before that is unknown...but likely we observe only a tiny fraction of the universe...nobody even knows if its infinite nor bounded nor unbounded.

If I understand bcrowell's explanation, it's a good/valid one based on CMBR radiation...red shift, right?? the remnanent radiation from the big bang. In other words, as the universe expands and ages, the red shift of the CMBR becomes more pronounced...wavelengths appear to get longer and longer due to cosmic expansion. All observers will see the same CMBR because there is no center of the universe...

In our universe, the preferred frame is the frame in which the average momentum of the CMB vanishes. The solar system is not at rest relative to this frame, as demonstrated by the dipole component of the CMB.

Is it correct to say that our measures/estimates at 13B years include a correction for our solar system movement? So other observers would have to make suitable corrections for theirs...

Also there are other ways to measure the age of the universe, which you can read about here:
http://www.astro.ucla.edu/~wright/age.html * The age of the chemical elements.
* The age of the oldest star clusters.
* The age of the oldest white dwarf stars.
 
Last edited:

1. What is the purpose of measuring the age of the universe?

The purpose of measuring the age of the universe is to gain a better understanding of the history and evolution of the universe. By determining the age, scientists can also make predictions about the future of the universe and the fate of the objects within it.

2. How is the age of the universe measured?

The age of the universe is measured through various methods, such as studying the expansion rate of the universe, the cosmic microwave background radiation, and the distance and brightness of objects in the universe. Scientists also use complex mathematical models and calculations to estimate the age.

3. Is measuring the age of the universe an objective observation?

Yes, measuring the age of the universe is considered an objective observation. This is because it is based on empirical evidence and scientific methods rather than personal opinions or biases.

4. What are some potential limitations in measuring the age of the universe?

There are several potential limitations in measuring the age of the universe, such as uncertainties in the data and assumptions made in the calculations. Additionally, the age may vary depending on the method and model used, leading to some discrepancies in the results.

5. Can measuring the age of the universe ever be a completely accurate measurement?

It is unlikely that measuring the age of the universe will ever be a completely accurate measurement. This is due to the vastness and complexity of the universe, as well as the limitations of our current technology and understanding. However, scientists continue to refine their methods and improve their accuracy in measuring the age of the universe.

Similar threads

  • Special and General Relativity
Replies
19
Views
627
  • Special and General Relativity
Replies
21
Views
383
  • Special and General Relativity
2
Replies
41
Views
4K
  • Special and General Relativity
3
Replies
70
Views
3K
  • Special and General Relativity
Replies
13
Views
2K
  • Special and General Relativity
Replies
2
Views
212
  • Special and General Relativity
Replies
34
Views
1K
  • Special and General Relativity
2
Replies
36
Views
2K
  • Astronomy and Astrophysics
Replies
3
Views
586
  • Special and General Relativity
Replies
21
Views
1K
Back
Top