Within a closed FLRW geometry with constant curvature, geodesic deviation is not zero. Does this lead to a frequency shift of photons? (If photons have a non zero spatial extension the geodesic deviation could lead to a shape deviation of the photon)
Why are we so sure, that there is no other effect than expansion of the universe and Doppler effect to explain the redshift?
If we live in a stationary universe of finite size, the theory of general relativity postulates a frequency shift in time!
If the universe is finite, then it must be...
Oh, what a tremendous waste of time. I would really appreciate a theory whith a much shorter renewal time of about a hundred billion (100_000_000_000) years.
May be we should check the possibility of a coordinated explosion of all black holes, if they are not kept blown-up by products of star...
Could it be that nuclear particles show a similar property like crushed atoms? In the "crushed" state still unknown subquark particles may play a major role. The principle even could be recursive in a way that subquarks of increasing order enter the game in more and more exotic conditions.
If you just measure the value of a physical property, zero is the smallest result. Assigning negative values to another property is a special case and not fundamental. The problem to measure a potential inifinite length has nothing to do with the subtleness of very small or signed quantities.
Why shall the future be a universe without the chance of life, though we live in a universe, which supports the existence of life? This kind of view is really depressive.
Aren't all known physical processes, which depend on time, appropriate to determine the time difference between two events?
Not too exotic examples are: Radioactive decay, cooling down of a hot object, a sandglass ...
Hi,
may be another view could help: Is the size of the universe measurable?
If a method could be identified, which allows to determine the size of the universe, then the universe has a finite size.
(Any thinkable means for this kind of measurement would be allowed)
Hi,
in physics, infinity is synonymous to "not measurable". As soon as you have got a measurement value for some infinite property, the value is too small. Therefor the question is: Is the size of the universe measurable?
Hi,
this discussion about Boltzmann Brains, which are only a statistical concept, has nothing to do with the existence of life forms in a late universe. The only possibility allowing life after all stars have been burned out is a renewal mechanism like a big bang or something else with the...