New Reply

Inflation & Quasars energy and 'fast-forward effect' ?

Share Thread
Feb14-13, 04:58 AM   #1

Inflation & Quasars energy and 'fast-forward effect' ?

Having read the 'The bigger bang' book two times over, I am struck by the fact that the author seems to ask and answer the question of quasar energy emission without stating he is doing so or explaining why it would be wrong to assume he is doing so.

In the beginning of the book, Lindsey states that at the very edge of the observable universe we see objects (quasars) that emit an unexplained amount of energy. In a later chapter on inflation, Lindsey explains that while the universe is still close to D, it is no longer inflating.

If I understand correctly and reason about my understanding, an object that would have been just outside of the visible universe from our perspective, would, resulting from the closeness to D have been 'just outside' for quite some time. This would seem to imply that once the passing of time expands the visible universe to include this object. If I reason about what would happen to the energy emitted by the object and the arrival time, it would seem that when the object drops into our visible universe, the energy arrival of the 'just outside' period will be virtually fast-forwarded to us as an observer, giving the 'illusion' of high energy emission.

That is, for me the combination of simple intuitive thinking and the facts that Lindsey sums up in his book make me conclude that any object at the edge of our visible universe should by means of such a fast-forward effect inevitably seem to emit massive amounts of energy, even though in reality it doesn't.

I had this nagging question the first time I read the book some years back, and asked about it on an other forum without getting any responses. After having re-read the book in order to see if I may have misread it the first time, I still end up with the same question.

Is this indeed how quasars work, and did Lindsey fail to mention this in his book, claiming falsely that quasar energy emissions were unexplained, or did I fail to understand the explanation en repercussions of the facts that Lindsey stated in his chapter on deflation? Or did I (and I find this extremely unlikely given my lack of astrophysical education) actually make a scientific discovery about quasars with nothing more than intuitive thinking?
PhysOrg.com science news on PhysOrg.com

>> City-life changes blackbird personalities, study shows
Feb14-13, 06:03 PM   #2
Gold Membership Gold Member
I don't believe so. I don't think the object would suddenly become visible as itself. I believe we can see as far back as recombination, about 380,000 years after the big bang, when the universe first became transparent to EM radiation, and as time passes the distance the light has had to travel increases. Anything entering our vision would start out as just gas at around 380,000 years after the big bang, and over time we would see it evolve into whatever it is now.

Note that this ignores the fact that the increasing rate of expansion will actually start to reduce the distance that we can see objects in the future.
Feb14-13, 07:52 PM   #3
Gold Membership Gold Member
Science Advisor Science Advisor
I was a little worried there for a minute, until seeing the book is by James Lidsey, not Hal Lindsey. The shortcoming of this book is it is a pop treatise of cosmology. Analogy is not always sufficient to convey the deeper meaning of mathematical physics. By the way, most scientists have been satisfied that black holes account for the energy output of quasars for a number of years. Lidsey was also unaware that expansion is accelerating, not stopped.
Feb15-13, 04:55 AM   #4

Inflation & Quasars energy and 'fast-forward effect' ?

@Chronos, he didn't say 'expansion' had stopped but 'inflation'. Not sure if I understand the difference correctly, but as I understood it seemed to mean that expansion was at a rate extremely close to some magical number where the edge of the observable universe would be in equilibrium, moving away from us at about the speed of light.

My interpretation of this would be that if there is indeed no perfect equilibrium, and our visible universe is slowly expanding to include new objects, than you would have the situation where energy that was send towards us N billion years ago, having relatively easily escaped the never to arrive point, would have traveled for N billion years to reach us, where as energy send towards us N billion minus a 2 seconds ago, having been send out at a point that the energy would never have arrived when in equilibrium, would have traveled N billion years and a second.
This in turn would mean that in a one second period we should see two seconds of energy being fast-forward received from such objects.

There could be a flaw in this reasoning, but if objects are actually dropping out rather than dropping into our visible universe, than it isn't relevant either way.
Feb15-13, 04:48 PM   #5
Gold Membership Gold Member
Science Advisor Science Advisor
Any galaxies we can hope to ever observe are necessarily between us and the CMB. Since we can already observe the CMB, we are already capable, in principle, of observing any galaxy that will ever become observable. Due, however, to accelerated expansion there are many galaxies currently emitting photons that will never reach us. This due to the cosmological event horizon [CEH] which limits how far back in time we can observe photons currently being emitted. Our current CEH is located around z~1.8. This means photons currently being emitted at distances in excess of z~1.8 will never reach us. z=1.8 represent a current proper distance to the source of about 16.2 Gly as compared to the current proper distance to the CMB of about 46 Gly. We can still observe CMB photons because they emitted over 13 billion years ago. We will never see what the CMB looks like today because photons currently being emitted by [what was] the CMB are beyond our CEH. For further discussion see http://arxiv.org/abs/astro-ph/0310808.
New Reply

energy, inflation, inflationary, quasars, universe

Similar discussions for: Inflation & Quasars energy and 'fast-forward effect' ?
Thread Forum Replies
How do inflation, and the zero energy flat universe tie into one another? Cosmology 2
pn junction, diode and energy level of conduction band during forward biasing Classical Physics 2
Opinions about April SciAm article about inflation inflation by Steinhardt? Cosmology 10
Fast Forward Real files Computing & Technology 0
Coriolis Effect on Fast Projectile Introductory Physics Homework 2