What many people seem to overlook is that gravity is linked to time (space time)!
So instead of the "black hole" being massive, it could be that time is running fast!
Rethinking the origins of the universe
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Re: Rethinking the origins of the universe
#12What many people seem to overlook is that gravity is linked to time (space time)! So instead of the "black hole" being massive, it could be that time is running fast!
interesting any reference/publications on this?
Re: Rethinking the origins of the universe
#13"In 1974, Stephen Hawking used quantum mechanics to show that black holes emit radiation. Since then, scientists have detected fingerprints in the cosmos that are consistent with this radiation, identifying an ever-increasing list of the universe’s black holes."
Er, what? I don't think this is true, or Hawking would have his Nobel prize by now. Maybe consistent in the sense that the predictions are that Hawking radiation is undetectably low for stellar mass black holes. Also, analogue systems don't count.
Re: Rethinking the origins of the universe
#14If I understand correctly, black holes do not play a large role in our model of the origins of the universe. So this doesn't (directly) lead to "rethinking the origins of the universe". Does this work call the big bang into question (or even our current models of the big bang)? Or is it just details like galaxy formation that it makes us rethink? Another question: Something very massive and very small is at the cente…
Your first point is correct: the relationship between black holes and the initial state of the universe is not clear. Whether or not there was a primordial singularity or something else is an open question.
With regard to the question "If not black holes, then what?", this is a problem. There is a strict upper limit on neutron stars of about 1.4 solar masses. Beyond this, gravity is stronger than the repulsive core of the strong nuclear force, and the star should collapse. If the process described in this paper is what actually occurs, the star will shed mass due to Hawking radiation while collapsing. The end-state of that process must be either a neutron star (which can't have more than 1.4 solar masses) or something else. There doesn't seem to be any "something else" in the offing, which makes that million-solar-mass thing in the centre of our galaxy deeply mysterious.
A new theory that makes an old "settled" phenomenon mysterious is not all that uncommon in the sciences, so it's reasonable to take a wait-and-see attitude toward this idea, but I'm not enormously hopeful that it'll pan out very well in the long run.
Re: Rethinking the origins of the universe
#15If I understand correctly, black holes do not play a large role in our model of the origins of the universe. So this doesn't (directly) lead to "rethinking the origins of the universe". Does this work call the big bang into question (or even our current models of the big bang)? Or is it just details like galaxy formation that it makes us rethink? Another question: Something very massive and very small is at the cente…
The beginning of the universe and black holes have in common the singularity if you think about it naively. Besides that there is not much of a connection. And I think most physicist don't believe there are real singularities in black holes or at the beginning of the universe but quantum mechanics, quantization of space and time or something else kicks in and prevents the singularity.
And there is no(t much) doubt that very massive dark objects are out there, we can observe them indirectly. So even if the classical black hole creation process turns out to be not possible, there are still objects out there that a very much like classical black holes.
Re: Rethinking the origins of the universe
#16Interesting; if the paper finds general acceptance, it'll be fun to watch a new flurry of activity. The fairly recent controversial concept of "firewalls" has reinvigorated that subfield of physics. Whether black holes exist or not, there's something really dense at the center of our galaxy. It's a challenge to come up with a consistent non-black-hole explanation for the observed motion of stars at the galactic cente…
This is why I love astrophysics (and the scientific method). When you find something conclusive (assuming the paper is accurate), and it causes you to re-think what you thought you knew about the universe, it suddenly becomes larger than you ever believed possible. I hope this paper is true - since it solves the information paradox.
Re: Rethinking the origins of the universe
#17[deleted]
Re: Rethinking the origins of the universe
#18Now that all the physicists are reading, I have a question: Are the trajectories of light beams following the curvature of space-time reversible? In other words, if I reflect a light beam back on itself, does it return to its source?
Because if that's true (and my feeble understanding is that it is true), then light can't enter a black hole or the reverse path would allow light to escape. What am I missing here?
Re: Rethinking the origins of the universe
#19Just downloaded the PDF, I am not a physicien nor a mathematicien.
but from what I read in the article the EQ 13, is the weakness of their argumentation.
AA
Re: Rethinking the origins of the universe
#20Just downloaded the PDF, I am not a physicien nor a mathematicien. but from what I read in the article the EQ 13, is the weakness of their argumentation. AA
Their boundery limit pose a problem, and then the entire solution in the extending (prior explosion) the radius is greater the rs, and so all the fellowing integral are wrong. but I will wait for Hawking opinion :)