i didn't see one of these (mods please feel free to combine/move/delete etc. if i missed it), and it seems we should probably have one given the various threads around and how closely related they can be.

so to start it off, here is the best article on inflation that i've seen to date:

http://scitation.aip.org/content/aip...1063/PT.3.2718

ITT, i'd guess we can discuss anything related to:
- cool new findings,
- new interpretations of old findings,
- quantum mechanics, cosmology, astrophysics, or anything related to how we understand the universe to function
- debates about quantum gravity/string theory/etc.

anything else? mods, is this ok?

I think this is a great idea. I encourage all our posters to be creative in participation and thread creation.

I will also note that we have an ongoing official smp news articles thread (link below) where all interesting/new News and/or articles on SMP subjects can be posted.

http://forumserver.twoplustwo.com/47...thread-797671/

thanks zeno.

great article thread too. i found the below inflation article via my facebook newsfeed (physics today). it's a bit more advanced than a standard news article (you def have to be somewhat familiar with the early stages of the evolution of the universe, understand quantum fluctuations, the cmb and a few other things, but you can skip all the equations and it's still a great article).

and thanks for the ok . hopefully we get some great discussions and new info. can't wait for the first results coming from the baller new LHC. c'mon miniblackhole detection!! there could be up to 2-3 nobel prizes that come from this new run, depending on what's found.

Definitely excited for the LHC to reach 13 TeV and see if anything interesting comes from the data there, though analysis will likely take several more years.

Amazing feat of engineering.

Also interested if this leads to any interesting results:

http://arstechnica.com/science/2015/...-using-x-rays/

so awesome:

and

supercool idea for an experiment in the article. i think they may be optimistic about the measurement aspect in the first example (where only gravity and not angular momentum is taken into account) and i think they may be possibly overlooking potential noise that the angular deflection idea might introduce. but that's just a layman's opinion, so i may be wrong. hopefully i am wrong as both of those experiments would be great.

When stars collide, and Hubble is watching.

http://www.slate.com/blogs/bad_astro...nocerotis.html

Wow.

So crazy that it's basically one giant , luminous strobe flash traveling through and illuminating interstellar debris.

Standard Candles not so standard and the universe's expansion not accelerating?

http://phys.org/news/2015-04-universe-fast.html

btw, I've never got it straight: Is it 1a or Ia supernovae?

i read this article from a few sources on my facebook feed and it was such a tease: "we now know that our measurements aren't accurate....and we'll have to redo a ton of work to know how far we're off...stay tuned" lol.

howard-> i've always read it as "type one a" not "type i a" (using arabic not roman numerals). as far as i know, we don't use roman numerals elsewhere in astrophysics.

also, whoever gets this done properly may be up for some kind of big prize. maybe not the nobel, but getting the correct expansion speed of the universe AND the revision of the usage of the two groups of "standard candles" (As you said, now not so standard) will def get some serious notoriety. it'll prob be like 10 grad students, 3 profs and 4-5 years of work though.

moving on:

1) https://www.quantamagazine.org/20150...ewalls-er-epr/

love this. i don't fully have my head around it yet (will have to read it a few more times probably) but the general concept is rather brilliant and i love the fact that it was communicated to susskind on a napkin kinda thing (just ER = EPR). i'm not sure how logistically the information survives or traverses these "octopus arm wormholes" from inside the black hole to the area of hawking radiation just outside the event horizon. i can't visualize the connection between particleA and particleB. previously, i thought the holographic thing they mentioned mostly solved it (info wasn't destroyed, just irretrievable for all intents and purposes and is conveyed on the inside of the black hole's event horizon, which, since things falling in become "infinitely elongated" it would make sense to see a holographic reflection of that thing on the inside of the event horizon.

that now appears to not be the case if the ER = EPR thing holds true.

2) https://www.quantamagazine.org/20150...ch-space-time/

this is just as, if not more, amazing. i can't figure out how this works in "the vacuum of space" though since there's nothing there, so i assume it has to do w/ the entanglement of the virtual particles that pop into and out of existence constantly (some entanglement there is what yields the structure of local spacetime in the vacuum of space). that's probably wrong though lol.

either way, very cool stuff here

Interesting. It would not surprise me much if it turned out there were no accelerated expansion and no dark energy at all.

Really? That would surprise me a ton. How else do we have:

1. 96 billion light year wide observable universe that's only 14b years old? And
2. No more than 3-4 degree K difference across the entire universe.

Without inflation, that's tough to explain.

I'm curious if this leads to an alternate explanation for evaporation of a black hole. Also I get how explain's the information paradox but not sure how it explains entanglement since we can induce and observe entanglement without black holes.

Also the author's love for painting in both articles leads to increadibly useless analogues. Haha.

It seems like they're saying entanglement is yet a fundamental undescribed property of space-time that has effects on particles as they move through it as opposed to a fundamental property of particles/energy. Could be wrong too though :-)

I meant the hypothesized currently happening "eternal" accelerated expansion driven by negative vacuum "dark" energy, but actually now that you mention it:
IF the standard candles turned out to be wrong wouldnt that also mean that both the size and the age of the universe would be different? And in turn this would also strongly affect theories about a possible early universe inflationary period.

Not quite sure what you mean here, if its about the CMB, its much less than 3-4 K difference. I agree that an inflationary period explains this reasonably well, but it may not necessarily be the only or correct explanation.

So the expansion rate was determined by the distance determined by faintness, and not redshift?

"fainter than expected" - how do they knew what's "expected"?

My buddy used to program the computers that ran the telescopes up on Mt Lemmon.

i'd have to double check this but i don't think so. this is talking about t1a supernovae compared to other supernovae whereas aging the universe used a variety of stars/baselines (i could be wrong here though).


yes, sorry. the avg CMB temp is about 3K, but the fluctuation is insanely small, like on the order of 0.1-0.2K

they mean brightness (luminosity): http://en.wikipedia.org/wiki/Cosmic_distance_ladder

that definitely impacts the use of standard candles.

https://www.newscientist.com/article...ime=1501124403