“Today we have touched Mars. There is life on Mars, and it is us—extensions of our eyes in all directions, extensions of our mind, extensions of our heart and soul have touched Mars today. That's the message to look for there: We are on Mars. We are the Martians!” -Ray Bradbury
It was a busy week, from science to politics to the simple question of Earth’s color here at Starts With A Bang. As always, you didn’t disappoint, with plenty to say about it all, and I’m stoked to continue the conversation. Just in case you missed anything:
- Are inflation and dark energy connected? (for Ask Ethan),
- The world's oldest street artist (for our Weekend Diversion),
- Ceres' secrets revealed (for Mostly Mute Monday),
- Could black holes be the engines of new galaxies? (a great Astroquizzical by Jillian Scudder),
- The difference a dark sky makes,
- and How the Higgs gives mass to the Universe (for Throwback Thursday).
I also had a couple of life-related (?) pieces in our Solar System over at Forbes:
- Where In Our Solar System Are We Most Likely To Find Life?, and
- How The Discovery Of Water On Mars Might Make Life Possible Today.
Also, for those of you invested in our Patreon, we have podcasts coming for all now, but patrons get it first! In addition, we're more than 2/3rds of the way towards having an official poster on the scientifically accurate timeline of the Universe created; it's going to be awesome! That said, let's dive on into our Comments of the Week!
Image credit: Bock et al. (2006, astro-ph/0604101); modifications by me.
From Ragtag Media on the end of inflation: "“The early Universe’s inflationary period lasted for an indeterminate amount of time — possibly as short as 10^-33 seconds, possibly as long as near-infinite”
How do you go from 10-33 to near Infinite time frame, what am I missing here.
Anyone?"
There were a lot of attempted answers to this, but I meant something very specific, and I wanted the opportunity to clear this up. Inflation does a few very important things in the very, very early Universe:
- it causes a very rapid, exponential expansion,
- it takes the topology of any pre-existing Universe and stretches it flat,
- it takes any pre-existing particles and expands them so far away that there's at most one left in what becomes our observable Universe,
- it creates quantum fluctuations that get stretched across the Universe, resulting in the seeds of cosmic structure,
- and finally, inflation comes to an end by "rolling down the hill" of the inflationary potential, with the decay/oscillations giving rise to matter, antimatter, radiation, energy, and what we know as the hot Big Bang.
Image credit: Cosmic Inflation by Don Dixon.
The problem is, we exist in the Universe after this hot Big Bang takes place. We can only observe what's causally connected to us -- what's had time to reach us in the expanding Universe limited by its 13.8 billion year history and the speed of light -- and the only "evidence" left to us in the Universe from before the hot Big Bang comes from the final 10^-33 seconds (or so) of inflation.
So from an evidence-based point of view, we only have the last 10^-33 seconds left to us. There are viable theoretical models where inflation lasts only that long and no longer, and there are models where it lasts much longer, and there are even models where inflation is eternal to the past. So we have a hard lower limit on time, but no upper bound. And that's where it comes from.
Image credit: HEMEDIA / SWNS Group.
From Broadstreet on the world's oldest street artist: "Why don’t you put a description under the pictures? Let my guess: you are busy writing “Image credit:”"
I sure am. Crediting images is vitally important; people need to be attributed for their work. I'm also of the opinion that illustrating my posts is of paramount importance, too, as visualizations help a great many people better understand what's going on.
Do you really need image captions for pictures of knitted street art? I do my best to provide captions where I feel the image needs an explanation for what's going on, but to me that's rather rare. What do all of you think?
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.
From PJ on Ceres' secrets: "Have been keeping an eye on Dawn/Ceres progress here:
http://dawn.jpl.nasa.gov/ I’ll stick with the salts.
What an achievement so far !"
I agree, and I think that salts is probably the leading explanation right now. I would've bet on ice a while ago, but with the angle the Sun is at and the level of radiation Ceres receives, I'm pretty sure it would've sublimated in short order. Salts appear the likeliest explanation to me, too, which probably means something pretty amazing:
- there must've been ions that dissolved in some liquid (water, anyone?),
- which then evaporated/boiled/sublimated,
- leaving these salty regions behind,
- which were then exposed by impacts.
If that's true, isn't that a hell of a story?
Image Credit: ESO/M. Kornmesser.
From Wow on black holes preceding galaxy formation: "A clincher for SMB preceding galaxy formation would be finding that they’re more liable to be offset from the gravitational centre of the galaxy the younger they are.
After all, there’s no reason to suppose that the black hole forms where the most collapsible matter happens to be.
My thoughts have always been that quasars may be two or more SMBs colliding to form what will be the galactic SMB we see in older galaxies like ours, or M31.
Such events may even say something on how you get an elliptical compared to spiral galaxy. Spirals would form as the result of the orbit of two merging black holes being naturally a planar event when there’s only two such objects doing the business."
This -- all of this -- is incredibly physically interesting. It's not thought you can have a supermassive black hole without having a period of star formation and the gravitational collapse and fragmentation associated with star formation, but until we can probe the first stars and proto-galaxies, we won't know for sure.
Image credit: NASA/JPL-Caltech/R. Hurt (SSC).
But I'm not entirely sure having massive black holes offset from the galactic center early on would be an indicator they precede galaxy formation. It's easy to imagine a scenario where young black holes form all over, say, a spiral galaxy, and then merge together and migrate towards the center, the same way mass segregation works in all sorts of astrophysical objects. We do see a few instances of galaxies with dual black holes, and some of them are (still) spirals. Here's one of my favorites.
Image credit: Gemini Obsercatory / AURA / Sydney Girls High School Astronomy Club / T. Rector / A. R. Lopez-Sanchez (AAO) / Australian Gemini Office, composite with Chandra X-ray Observatory, stitching by me.
There's a merger going on, to be sure, but the "smaller" galaxy (about the size of the Milky Way) very clearly has two black holes in it, as the X-ray shows.
But there's no reason to believe this galaxy will become an elliptical. I think your scenario, Wow, is plausible, but by no means is it going to explain 100% of what we see.
Image credit: GNI Phoenix International, via DIYTrade.com.
From LdB on the Higgs and mass: "Ethan the article is a bit misleading, it reads like you think the Higg’s (sic) is the universal giver of mass."
Let me be universally clear, then: the Higgs is the universal giver of mass to particles with a non-zero rest mass, as far as we can tell. This may or may not include dark matter; this may or may not include neutrinos. (Both of these could get their mass from a different mechanism.) But all the quarks, all the charged leptons, the Z and W bosons, and the Higgs boson itself all derive their rest masses from the Higgs field.
Now, composite, bound combinations of these particles have other sources for their mass: protons get their mass from the strong force, for example. But yes, the Higgs gives mass to everything. Most importantly, without a mass -- if the quarks were all massless -- bound states like protons would not be possible. So while there are other sources for some forms of rest mass, there's quite possibly nothing at all with a rest mass without the Higgs.
Image credit: Wikipedia / Wikimedia Commons user Qashqaiilove.
From david on couplings: "“The fact that there’s a self-coupling — something special to the Higgs — makes the Higgs boson different than all the other particles, but also explains why it has mass at all.” — Don’t gluons also self-couple?"
Yes! Yes they do. In fact, gluons -- since they have a color charge -- couple to other (colored) gluons, which is part of what makes QCD so difficult to do perturbative calculations with. If you're willing to go to higher loop order, photons self-couple as well (even though they don't without "loops"), which is how you can have photon-photon interactions. The W's and Z's likely self-couple too, meaning that all the bosons do.
So I misspoke here.
Image credit: Ned Wright / Sean Carroll, via https://ned.ipac.caltech.edu/level5/March01/Carroll3/Carroll4.html.
And finally, from Pavel on gravitational self-coupling, "And gravitons as well…"
This one is really interesting, and -- of course, like all aspects of quantum gravity -- is an open area of research. (See here, for an example.) Yes, if you write down a field theory, you do get terms where gravitons do couple to one another and get exchanged in graviton-graviton interactions. But this does not necessarily mean they self-couple, not if these interactions, when all the terms are accounted for, wind up being equivalent to a free field theory. (And they may; this happens for scalar Φ^4 theory, which appears to have non-zero terms at finite loop order.)
So gravitons may self couple, or they may not. It will take a lot more physics -- theoretical and experimental -- to know for sure! Thanks for a great week, and I hope we all learned a lot together; I know I did!
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"But I’m not entirely sure having massive black holes offset from the galactic center early on would be an indicator they precede galaxy formation"
My probs: Said the opposite of the meaning.
If SMBs form after the galaxy got settled, then they would be formed where the most stars were settled. If they CAUSE the galaxy to form, things would set up round them.
Cheers for that I believe it is much more correct to anyone interested in science who reads it. We can all add our favourite brain wave and pet idea under it to connect it but that is just all speculation and hyperventilation.
People with ideas on connecting them like some String Theorists and WOW may complain because they claim they know the answer and are so convinced of it that everyone else has to prove them wrong.
That however is not how science works and thank you for taking the time to clarify that because I think it was important.
"Cheers for that I believe it is much more correct to anyone interested in science who reads it."
How would you know?
You admit to being clueless and merely repeat something someone else says and have NO INTEREST in whether it's right or not, you disclaim ALL KNOWLEDGE of it.
"People with ideas on connecting them like some String Theorists and WOW may complain"
Yes, morons JAQing off on the internet really DO deserve complaints. The morons try to make it the rationalists' fault, though through a moral failure that they know, despite not knowing anything other than their own conjecture.
"because they claim they know the answer "
Just because I don't let you claim you DON'T know what you're talking about DOESN'T mean I claim to know the answer.
But, again, morons will rewrite reality to conform to a comforting picture of themselves and demonaic one for those that do not let them play enlightened.
"and are so convinced of it that everyone else has to prove them wrong. "
ROFL!
That's PRECISELY what you have been doing! "Prove these two people are wrong!". And one of the other lurker morons even came out deliberately and said *specifically*, I had to prove the people you cited were wrong.
Morons really don't realise what they're doing. There's no malice, just an incapacity that makes them so tiresome.
"That however is not how science works "
Actually, you have that entirely wrong.
There is an irony for poor WOW that the person he probably hates most and calls an "insane nutcase" AKA Lubos Motl could almost be his twin.
I have had this exact (and I do mean exact) argument with Lubos and he could connect all this with big equations in umpteen dimensions and no I can't fault his mathematics either. Now that is one up on WOW who hasn't even given us the full connection theory.
However like WOW he still wasn't right because he lacked something most of us call evidence or perhaps data ... yeah his dog ate his as well :-)
Now physics is full of nutcase crackpots who think we should have to prove them wrong lets introduce some
Israel Socratus:
https://il.linkedin.com/pub/socratus-sadovnik/82/345/804
Sorin Cosofret:
http://www.elkadot.com/index.php/en/
Maciej Marian Marosz :
http://tesla4.blogspot.com.au/
Can't prove any of these guys wrong either and they have Youtube videos ... does WOW have youtube videos?
Makes it all the more compelling apparently if you are on youtube and web.
I probably should deal specifically with this claim
WOW quote: "You admit to being clueless and merely repeat something someone else says and have NO INTEREST in whether it’s right or not, you disclaim ALL KNOWLEDGE of it."
Now I never said I was clueless I did say I am a nobody which is true. You turned that into clueless, moron etc which is how you tend to argue via insult strangely like you arch nemesis Lubos Motl does and no surprise he thinks he is smarter than everyone else as well.
For the next bit well I had enough interest and knowledge to know what was said was incorrect didn't I?
Now you still seem to be playing with sock puppets again so I am not sure who I am supposed to address. Ethan complaining about me complaining or WOW complaining that I can't prove him wrong.
Remember YOU said yo were the clueless one. YOU said you didn't know anything about this.
Apparently, taking your word for it is arrogance on my part.
Who'd'a'thunit!
"“insane nutcase” AKA Lubos Motl could almost be his twin."
Not really. Never stalked someone or threatened them with vicious murder. Also never talked BS about AGW being false.
"I have had this exact (and I do mean exact) argument with Lubos and he could connect all this with big equations in umpteen dimensions and no I can’t fault his mathematics either. "
Then if you're not going to be able to reject and won't accept a claim, WHY THE HELL ASK IT?
JAQing off, isn't it.
"Now physics is full of nutcase crackpots who think we should have to prove them wrong lets introduce some"
And the internet is full of moronic blowhards who can't understand their own problems.
GSW, Stu2, Brad Keyes, Duffer, Girma Orresango, Lubos, and so on.
Yup, you're associated with a list of ignorant morons who won't accept or refute anything, just want to piss and moan on the internets how they're being mistreated by a cult. Guess why.
"Now I never said I was clueless "
Oh yes you did!
http://scienceblogs.com/startswithabang/2015/10/01/throwback-thursday-h…
“I have nothing to comment on I admit I don’t have a clue”
Derp!
Ah you got me there :-)
In my defense even as clueless, I did at least know the answer of what amounts to a pretty basic first year science grad question. The answer was derp which is why it drew my attention, I was like WTF?
All that aside you insulted Mike who obviously works at SLAC and was clearly going to know the answer, I couldn't work out why you went there?
The problem was never with the connection, there are a number of proposed theories that will create the connection to the Higgs including good old String Theory. Your mate Lubos could probably give you a number that will fit the bill.
The problem is there simply is no evidence or data to support the assumptions you need to create those connections.
"I did at least know the answer of what amounts to a pretty basic first year science grad question. "
Which one was that?
Because the difference between the mass of the proton or neutron and the mass of its stationary components was not the question AT ALL.
"All that aside you insulted Mike who obviously works at SLAC"
Yeah, and? Working at SLAC doesn't mean you're inviolate. It CERTAINLY doesn't mean you get to claim "Hey, they were wrong" and then go on about SOMETHING ELSE and expect not to be called out on the difference in a disparaging way.
Indeed, it's BECAUSE he works at SLAC that he gets LESS shrift than the man-on-the-street for a topic error, since his training should make that option nonexistent.
"and was clearly going to know the answer, "
And Ethan who said what you queried ALSO has equal eminence, yet YOU clearly thought he DIDN'T know the answer.
Thing is, he knew the answer FOR A DIFFERENT QUESTION. He's done that before. A few times.
"Your mate Lubos could probably give you a number that will fit the bill."
He's your mate, not mine.
"The problem is there simply is no evidence or data to support the assumptions you need to create those connections."
The problem is that your claims were nothing like that supported by this lack.
The higgs gives mass to things with mass. Most of the universe (visible, definitely) with mass gets it from there. Neutrinos *may not*, then again, they may. But they don't constitute much of the universe.
The fact that most of the rest energy of the proton or neutron are not the constituent quarks is as relevant to this as the fact that most of the atom is empty is.
Quite why you think otherwise is just standard ignorance. Mike getting it wrong, slightly more serious.
Probably best that you avoid the use of the term "universal giver" then if that isn't what you mean.
The rest then goes we can't question Ethan because of his eminence even when it would appear he has said something weird possibly wrong.
Yeah right we didn't afford that right to Einstein get over yourself.
Can I suggest if you really feel that way then it is time to change profession or turn the comments off the forum.
Anyhow I got the position you want to take loud and clear and will leave you to it.
"the Higgs is the universal giver of mass to particles ..."
To be more precise it should be the 'Higgs Field' to prevent confusion with the 'Higgs Boson'.
And I would add 'the interaction with' the Higgs Field. Just like a ship won't 'sail' without a sail even if there is wind. So it's the interaction of the particles with the Higgs Field that creates the phenomenon that we call mass. They work on each other it goes both ways.
"To be more precise it should be the ‘Higgs Field’ to prevent confusion with the ‘Higgs Boson’."
Well, we use photon and electric field without confusion, so I don't think it *necessary*. They're just using two different models of reality.
"Can I suggest if you really feel that way then it is time to change profession"
Why? Concern trolling now?
"Probably best that you avoid the use of the term “universal giver” then if that isn’t what you mean."
Why?
"The rest then goes we can’t question Ethan "
Apparently we can't question Mike. So why is Ethan such a big dog to swallow?
Sure, given that the Higgs boson is only one of the field's degrees of freedom, but "Higgs mechanism" would probably be the clearest of all.
I guess it depends on what you're trying to explain.
Like any physical model.
Of course a person can question the unquestionable. If you can't, then you're pushing a religion [ see Steve Eley's Faith Of The Invisible Pink Unicorns]. "Science is questions that may never be answered, and Religion is answers that may never be questioned."
If you think of the universe as an expanding wavefront and all its matter as the particle duality, you might be able to explain dark energy. Gravity is retarding the expansion velocity of the wavefront. But as the universe expands, gravity becomes weaker and the velocity approaches the speed of light.
Well that was a load of nonsense, Greg.
Testing your school's AI project?