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Black holes, the winged seeds of our Universe January 8, 2009

Posted by dorigo in astronomy, cosmology, news, science.
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From Percy Bysshe Shelley’s “Ode to the West Wind” (1819), one of my favourite poems:

[…]O thou,
Who chariotest to their dark wintry bed
The winged seeds, where they lie cold and low,
Each like a corpse within its grave, until
Thine azure sister of the Spring shall blow
Her clarion o’er the dreaming earth, and fill
(Driving sweet buds like flocks to feed in air)
With living hues and odors plain and hill:
Wild Spirit, which art moving everywhere;
Destroyer and preserver; hear, oh, hear!

The winged seeds -of galaxies, and ultimately of everything that there is to see in our Universe- appear today to be black holes: this is what emerges from the studies of Chris Carilli, of the National Radio Astronomy Observatory (NRAO). In a press release of January 6th, Carilli explains that the evidence that black holes are antecedent to galaxy formation is piling up.

In a nutshell, there appears to be a constant ratio between the mass of objects like galaxies and giant globular clusters and the black hole they contain at their center. This has been known for a while -I learned it at a intriguing talk by Al Stebbins at the “Outstanding Questions in Cosmology” conference, in March 2007 at the Imperial College of London. But what has been discovered more recently is that the very oldest objects contain more massive black holes than expected, a sign that black holes started growing earlier than their surroundings.

This is incredibly interesting, and I confess I had always suspected it, when looking at the beautiful spiral galaxies, attracted in a giant vortex by their massive center. I think this realization is a true gate to a deeper understanding of our Universe and its formation. A thought today goes to Louise, who has always held that black holes have a special role in the formation of our Universe.

Comments

1. mark a. thomas - January 8, 2009

Another feather in the cap of inflation cosmology.

2. Dyson flying frog - January 9, 2009

Unless there’s another person who has joined the Backreaction duo, I think “Louise” is incorrectly hyperlinked.

3. Kea - January 9, 2009

Excellent. Hopefully Louise will also post about this interesting work.

4. dorigo - January 9, 2009

Hi Dyson, thanks, fixed. Backreaction and Babe in the Universe are next to each other in my blogroll, and I took the link from there….

Yes Kea, I do hope so.

Cheers all,
T.

5. cormac - January 9, 2009

Excellent post, T. I read a short paragraph on this in the newpaper today, was astonished it didn’t get more attention .
Though the idea has been around for some time, hasn’t it? Great to see some real evidence. Cosmologists seem to have all the fun these days…

dorigo - January 10, 2009

Yes, I did not see anything about it in several sites that should have reported this news. Roses will bloom.

Cheers,
T.

6. Louise - January 10, 2009

Thanks for the link! A post about Black Holes is coming soon!

7. carlbrannen - January 12, 2009

The poetry reminds me. I like to see the cosmic ray talks at physics conferences (cause I think that’s where we’re most likely to see new physics), and at one of them there was an old amateur who gave a talk on black holes. He basically said that God wouldn’t design a universe where everything goes into a hole and nothing comes out.

I suppose I should link Kipling’s poem Tomlinson which I love for its astronomical imagery (dated late 19th century)

Till they came to the belt of Naughty Stars that rim the mouth of Hell:
The first are red with pride and wrath, the next are white with pain,
But the third are black with clinkered sin that cannot burn again:
They may hold their path, they may leave their path, with never a soul to mark,
They may burn or freeze, but they must not cease in the Scorn of the Outer Dark.
The Wind that blows between the worlds, it nipped him to the bone,
And he yearned to the flare of Hell-Gate there as the light of his own hearth-stone.

8. D R Lunsford - January 18, 2009

I have to vehemently disagree here. Never has so much been assumed of something so unobserved.

One – there is very little likelihood that GR survives in its current form down to the smallest levels. This cannot be stressed enough. If one believes that gravity and the other interactions have a common origin, no matter what its form, then it is preposterous to assume that the simple form Gmn = k Tmn survives at all interaction strengths. In fact the full equations of GR are completely untested – not partially, COMPLETELY – only Rmn = 0 is actually tested to any accuracy. We cannot get ourselves into a dense matter situation where the full equations are testable. Looking in from infinity is not a substitute. G = kT must be seen as a second weakest approximation, after R = 0. In fact the full solution must solve the energy problem of GR and that will mean the Newton constant will be given a dynamical origin.

Two – by simply foisting off everything onto unobserved black holes, one is abandoning his responsibility as a physicist to provide solid explanations for new phenomena. By simply bending the old formalism around every situation, one guarantees that new phenomena will never be observed, and we will be stuck with the limitations of worn out theoretical ideas ad infinitum.

Three – Cooperstock and Tieu remain marginalized and misunderstood. The non-linearity of GR is not something that can be approximated away – like the equations of fluid flow, the non-linearity has consequences at all scales. Therefore existing post-Newtonian models are all inherently wrong. These are problems that need to be studied harder, and one needs to stop invoking the default answer in all situations.

Of course it is a forlorn hope. And so a correct understanding of gravity will remain forever obscured and out of reach.

-drl

9. dorigo - January 18, 2009

Hello DR,

I do not quite understand what you disagree with… Could you explain it in more mundane terms ? What is wrong with the observation of a constant ratio between black hole mass and host body ? Do you object to the experimental observations or their interpretation ?

Cheers,
T.

10. Danny Ross Lunsford - January 18, 2009

Yes I strenuously object to even referring to this as an experiment. GR has insuperable difficulties as it stands – Tmn;n is not a conservation law, G is not a coupling constant, and as a result, even something as simple as defining gravitational radiation poses huge interpretive challenges, not to mention the collective behavior of dense matter as in a galaxy core. People should be working on the problems intrinsic to the theory before announcing that most all the phenomena of the Universe rest on the shoulders of its main pathology. I firmly believe that many people fail to accurately understand special relativity, much less so the theoretical structure of its big brother. Much is said in the name of GR that is flat wrong, and much is ignored that is absolutely correct (Cooperstock’s work).

-drl

11. Nige - January 22, 2009

Lunsford refers to Cooperstock and Tieu, General Relativity Resolves Galactic Rotation Without Exotic Dark Matter, http://arxiv.org/abs/astro-ph/0507619, pp. 17-18:

‘One might be inclined to question how this large departure from the Newtonian picture regarding galactic rotation curves could have arisen since the planetary motion problem is also a gravitationally bound system and the deviations there using general relativity are so small. The reason is that the two problems are very different: in the planetary problem, the source of gravity is the sun and the planets are treated as test particles in this field (apart from contributing minor perturbations when necessary). They respond to the field of the sun but they do not contribute to the field. By contrast, in the galaxy problem, the source of the field is the combined rotating mass of all of the freely-gravitating elements themselves that compose the galaxy.’

Sean Carroll criticised it on a technical level because he felt it wasn’t rigorous: http://blogs.discovermagazine.com/cosmicvariance/2005/10/17/escape-from-the-clutches-of-the-dark-sector/

But I’ve seen a different, cleaner or more straightforward-looking analysis of the galactic rotation curves by Hunter that appears to tackle the dark matter problem at http://www.gravity.uk.com/galactic_rotation_curves.html (I want to point out though that I don’t agree or recommend the cosmology pages on the rest of that site). His interesting starting point is the equivalence of rest mass energy to gravitational potential energy of the mass with respect to the surrounding universe. If the universe collapsed under gravity, such potential energy would be released. It’s thus a nice conjecture (equivalent to Louise’s equation since cancelling m and inserting r = ct into E = mc^2 = mMG/r gives c^2 = MG/(ct), or Louise’s tc^3 = MG), and leads to flat galactic rotation curves without the intervention of enormous quantities of unobserved matter within galaxies (there is obviously some dark matter, from other observations like neutrino masses, etc.).

But this is pretty trivial compared to the issue of quantum gravity. What should be up for discussion is Lunsford’s paper http://cdsweb.cern.ch/record/688763?ln=en but it is just too abstract for most people. Even people who have done QM and cosmology courses (including basic GR) don’t have the mathematical physics background to understand the use of GR and QFT in that paper, e.g. the differential geometry, variational principle, and so on.

I wish he could write a basic textbook of the mathematical foundations used in his paper. I’ve learned some useful mathematics from McMahon’s Quantum Field Theory Demystified (2008), Zee’s Quantum Field Theory in a Nutshell (2003) Dyson’s http://arxiv.org/PS_cache/quant-ph/pdf/0608/0608140v1.pdf and the QFT lectures http://arxiv.org/PS_cache/hep-th/pdf/0510/0510040v2.pdf

A QFT of gravity will differ from GR. Instead of curved spacetime, you have discrete graviton exchanges causing the interactions (gravity, inertia, and the contraction of both stationary and moving bodies composed of mass-energy). Some energy will exist in the graviton field, and surely this is the dark energy. There is no supplemental ‘cosmological constant’ of dark energy in addition to the gravitational field. Instead, the gravitational field of graviton exchanges between masses will cause expansion on large distances and attraction on smaller ones.

Think of the analogy of a raisin cake expanding due to the motion of the dough. Nearby raisins (with little or no dough between them) will be pushed closer together like ‘attraction’, while distant raisins will be accelerated further apart during the cooking, like a ‘repulsion’ effect. Two phenomena for the price of one graviton field! No additional dark energy or CC, just the plain old gravitational field. I think this is missed by the mainstream because they (1) think LeSage came up with quantum gravity and was disproved (he didn’t, and the objections to his ideas came because he didn’t have gravitons exchange radiation, but a gas), and (2) the Pauli-Fierz ‘proof’ that gravitons exchanged between 2 masses to cause them to attract, must suck, which implies spin-2 suckers.

Actually the Pauli-Fierz proof is fine if the universe only contains 2 masses which ‘attract’. Problem is, it doesn’t contain 2 masses. We’re surrounded by masses, and there is no mechanism to stop graviton exchanges with those masses. As gravitons propagate from distant masses to nearby ones, they converge (not diverge), so the effects of the distant masses are larger (not smaller) that that of nearby masses. Once you include these masses, the whole basis of the Pauli-Fietz proof evaporates; gravitons no longer need to be suckers and thus don’t need to have a spin of 2. Instead of having spin-2 gravitons sucking 2 masses together in an otherwise empty universe, you really have those masses being pushed together by graviton exchanges with the immense masses in the surrounding universe. This is so totally obvious, it’s amazing why the mainstream is so obsessed with spin-2 suckers. (Probably because string theory is the framework for spin-2 suckers.)

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