tag:blogger.com,1999:blog-10614348.post2609155836984351785..comments2024-01-22T11:26:37.599-08:00Comments on TGD diary: Is cosmic expansion a mere coordinate effect? Matti Pitkänenhttp://www.blogger.com/profile/13512912323574611883noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-10614348.post-24128960049300420472014-09-24T08:22:37.290-07:002014-09-24T08:22:37.290-07:00To Anynymous:
I commented BICEP2 in the next po...To Anynymous:<br /><br /><br /> I commented BICEP2 in the next posting and also in two postings previously. I more or less agree with you. <br /><br /><br />What is common with TGD and inflation is vanishing curvature of 3-space. In TGD it is correlate for quantum criticality in transition from cosmic string gas phase (cosmic strings as space-time surfaces with 2-D M^4 projection) to radiation dominated cosmology. What is also common is rapidly accelerating expansion.<br /><br />The energy of inflaton field is replaced with the magnetic energy of flux tubes which decays to particles so that no new primary fields are introduced and also standard model gauge fields reduce to four imbedding space coordidates as field like variables.<br /><br />TGD model explains also the presence of magnetic fields in cosmological scales: in this respect the model differs from inflation model. Of course it is of course dramatically simpler: four field like like variables instead of gauge fields, Higgs field, inflation field, etc… This is magic of geometry and topology.Matti PItkanenhttp://tgdtheory.fi/noreply@blogger.comtag:blogger.com,1999:blog-10614348.post-36809381221253740122014-09-24T06:17:44.648-07:002014-09-24T06:17:44.648-07:00I'm sure you noticed this Matti, but the BICEP...I'm sure you noticed this Matti, but the BICEP2 data on gravitational wave proof of inflationary universe has now been explained as magnetic dust measurement anomaly.<br /><br />http://www.simonsfoundation.org/quanta/20140921-big-bang-signal-could-all-be-dust-planck-says/<br /><br />So much for direct (or actually, indirect) proof of inflation.<br /><br />It's still only a model. Testable, but not proven.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-10614348.post-45048118830656087432014-09-21T21:39:14.673-07:002014-09-21T21:39:14.673-07:00
To Zephir:
The question of the title was purpos...<br />To Zephir:<br /><br />The question of the title was purposefully provocative. I am of course not against Big Bang!<br /><br />Big Bang is part of TGD and also of reality, as I believe with the reservation that in primordial state one has just a gas of cosmic strings near the boundary of light-cone and mass density goes like 1/a^2 and mass per comoving volume goes to zero. Silent whisper amplitude to quite a big bang would be a more appropriate term. TGD counterpart of inflationary period means transition to a radiation dominated cosmology.<br /><br />My point is that light-cone proper time which gives cosmological expansion already in empty Minkowski space is physically appropriate in zero energy ontology. In this sense cosmic expansion is coordinate effect. The challenge is to explain why R-W coordinates are appropriate.<br /><br />These coordinate effects are dangerous concerning interpretation: for instance, the canonical form of inflationary cosmology (de-Sitter space) allows imbedding as completely static cosmology having no Big Bang and this brings in physics.<br /><br />Causal diamond - in cosmological scales very big one - is intersection of future and past directed light-cones. In Robertson-Walker cosmology the time coordinate ) is light-cone proper time a (or function of it) for its imbedding as space-time surface and thus very natural since R-W can be imbedded inside light-cone and its boundary corresponds to the Big Bang. <br /><br />R-W cosmology is Lorentz invariant so that energy momentum tensor is extremely simple in these coordinates. In linear Minkowski co-ordinates things would look very complex. <br /><br />Hence Big Bang is real but looks simple in R-W coordinates made natural by the Lorentz<br />invariance of the space-time surface characterizing R-W cosmology. <br /><br />Matti PItkanenhttp://tgdtheory.fi/noreply@blogger.comtag:blogger.com,1999:blog-10614348.post-79614176660512251102014-09-21T14:49:27.545-07:002014-09-21T14:49:27.545-07:00/* Big Bang theory certainly explains a log of thi.../* Big Bang theory certainly explains a log of things. */<br /><br />Epicycle model explained lotta eclipses and conjunctions, yet it was wrong. <a href="https://www.blogger.com/comment.g?blogID=30708128&postID=7876096212331290698&page=1" rel="nofollow">Here</a> you can find much more arguments against Big Bang scenario.Zephirhttps://www.blogger.com/profile/06010623752049244967noreply@blogger.com