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Nereid is offline
Dec25-08, 01:46 PM
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Quote Quote by heldervelez View Post
quoting the above mentioned paper
From the theoretical viewpoint the main weak points of CDM include [10]:
The Fine Tuning Problem: What is the physical mechanism that sets the value of  to its observed value which is 120 orders of magnitude smaller than the physically anticipated value?
The Coincidence Problem: Why is the energy density corresponding to the cosmological constant just starting to dominate the universe at the present cosmological time?

beeing the above statments without formal denial I think that each one is a theory killer.

the first statment I read: the theory, at least this one, can make whatever value has a prediction and make an error to the observed value of the magnitude of the universe.
p= prediction
o=observed and p~= o^120 or p~=o^(-120) (is irrelevant a + or - in the exp.)
As Dmitry67 has already noted, the relevant theory is QM, or at least the standard model of particle physics.

But it's been known for some time now that there is a mutual incompatibility between QM and GR, and also that the universe is perfectly capable of showing us new physics in energy domains beyond our current reach; for example, how much new physics is there between 1eV and 1 MeV (say), some 6 orders of magnitude (OOM)? between 1 MeV and 1 TeV (another 6 OOM)? What about between 1 TeV and 1 EeV? And for context, let's keep in mind that UHECRs (ultra-high energy cosmic rays) have been observed with energies just shy of 1 ZeV.

Maybe you have a somewhat unrealistic view of what scientific theories can - and cannot - do?
the 2nd statment I read: forget Galileu and Einstein, after all we live at the center of the Universe (some kind of center).

to me, those statments are deadly killers, and the paper continues with some 6 minor puzzles (compared to that tantalizing statments), and finally the documents concludes, in proper words: we have to do a major patch in the theory.
It does?

Here's what my copy of the paper says, in its last para:
In conclusion, the six puzzles for CDM discussed in the present study provide a fertile ground for the development of both new theoretical model predictions on the corresponding observables and new observational data that would either establish or disprove these challenges for CDM.
May I ask how you read "major patch" into this?