How is the age of the universe theorized?
10835
How has the age of the Universe been derived from the observations made by the Planck mission?
100760
How do we know that radioactive decay rates are constant over billions of years?
92343
Does cosmological time expand like space does?
27547
How energy curves spacetime?
106350
Dumbed-down explanation how scientists know the number of atoms in the universe?
58042
Redshifting of Light and the expansion of the universe
2983
Shape of the universe?
67661
Is there an observable of time?
89301
Is the total energy of the universe constant?
3103
How do we know the universe is expanding, and not that its contents are shrinking?
25052
Doesn't dating the universe violate the concept of spacetime's inseparability?
126407
How does the Doctor's aging work?
51361
How does the Hubble parameter change with the age of the universe?
21084
Size of the universe
84062
The Time Freezing Room - Theoretically possible?
81495
Does the universe have a different age to different observers?
108569
Time dilation - why the observers see each other the slow one but then one of them is older or younger?