Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Rethinking the origins of the universe

unc.edu

Post reply on HN
Print view View original

41–50 of 141 posts

Re: Rethinking the origins of the universe

#41

Post by collyw »

vorg wrote: post #29
tfgg wrote: post #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 radia…

> "Stephen Hawking used quantum mechanics to show that black holes emit radiation." I don't think this is true, or Hawking would have his Nobel prize by now Hawking not getting a Nobel by now doesn't mean much. Einstein never got one for relativity (either Special or General), and when he did get his Nobel he was told not to mention "relativity" in his speech.

Obama got a Nobel peace prize!

Re: Rethinking the origins of the universe

#43

Post by [deleted] »

faizshah wrote: post #36

I'm not at all acquainted with astrophysics but I remember seeing an article state that there was a different physicist who proved this same thing: https://news.ycombinator.com/item?id=7191324 A quick google shows his response to this: https://twitter.com/abhasmitra/status/514804101024997376 His response: "Hawking radiation is unproven. And particle physicists are not aware that even without any Quantum Mechanics, cl…

[deleted]

Re: Rethinking the origins of the universe

#46

Post by anigbrowl »

tericho wrote: post #39

Ethan Siegel just posted a detailed response to this. https://medium.com/starts-with-a-bang/yes-virginia-black-hol...

That was written in February (how could you miss this? it's literally the very first thing at the top of the page) and doesn't mention either of this paper's authors. The article discusses a closely related but nevertheless quite different topic.

Re: Rethinking the origins of the universe

#47

Post by scobar »

The article mentioned, "Mersini-Houghton shows that by giving off this radiation, the star also sheds mass. So much so that as it shrinks it no longer has the density to become a black hole."

If anyone else wondered how the radiation of massless particles could result in the reduction of mass, I've found a resource with simple explanations for a layperson like myself. https://www.physicsforums.com/threads/mass-lost-by-the-sun-b...

Re: Rethinking the origins of the universe

#49

Post by guscost »

Another member of the peanut gallery here. I've not been bold enough to make any claim in writing (it would probably be full of misconceptions), but the black hole hypothesis always seemed a bit half-baked, and I've definitely said words to that effect in conversation.

In the hypothesis Einstein's field equations obviously break down, and instead of acknowledging that any explanation will be enormously difficult to test we seem to have bought into this completely untested idea that matter can continue bending space-time around into a singularity and all that. Can someone with a better understanding point out what logic is (probably) missing here?

The other thing that sets off my hand-wave-o-meter is the pretending that we are somehow already observing these things ("new telescope detects hints of black holes") or have concluded that they exist without any positive evidence. Instead of "the mass at the center of the galaxy which is so large that we currently have no good way of modeling it without a black hole" we hear "the supermassive black hole at the center of the galaxy" and so on.

Re: Rethinking the origins of the universe

#50

Post by dhimes »

sramsay wrote: post #28

I'm not a physicist. I imagine that if I were, this would be exciting news (that is, an exciting possibility). I am a literary critic, though, and I have to say that it's bittersweet news at best. Black holes are so much a part of the space-age imagination. The article mentions Hollywood, but black holes are woven deeply into our everyday metaphors and have been for decades. They have stood among the most wondrous th…

I imagine that the metaphor "black hole" will be here for a while. After all, we still use the term "big bang" for the 'first moment' of the creation of the universe, even though the "Big Bang Theory" isn't generally believed any longer.
Post reply on HN