Astrophysics and Cosmology - Discuss the Universe here

[Mind Flayer Monk]

but hey man, inquiring minds want to know! 

Welcome back a51D, and good questions.

[DigitalPigSnuggler]

If one could contract space, would time go in reverse?

No, because it would violate the second law of thermodynamics. 

[Rudolf Zlabinger]

Dear Agent : Orange,

to give special attention to your topic, that lead me to this forum originally by google, and by recommendation from onan, I will relate the issue to my "A discrete model of cosmology".

In the sense of my special model particles are partial graphs differing from empty space by density of edges between the elementary constituents of universe as vertices. The manifold possible is not restricted to a determined number of dimensions, as these have no correspondence in the model yet, and so there are most scary particles possible, as seen from the viewpoint of the model. Seen from there, the detection of more and more and also strange particles is of no importance at all.

The situation seems to be that of children, looking for and finding toys, and are fascinated at the end detecting the unrestricted possibilities of construction sets allowing to make toys as they can imagine. (You perhaps remember to Matador or PlayMobile and more...)

But this is the situation of science at now, and so let us stay curious, what they find next.

I will keep attention to your topic, best regards, Rudolf Zlabinger       

[Tarbaby]

Yup. I don't find any of this stuff in this thread the least bit intuitive. Every time I think I'm starting to get some issue or concept I find out from agent orange quite the contrary.   I still have no idea why galaxies and solar systems form in a spiral even though both you and Agent Orange took a crack at  telling me why. All I could understand (just based on my own reasoning) is that objectss going through  space at the right speed either get trapped into an orbit or they are going too fast and escape the gravitational pull. Or are going too slow and fall into the gravity source. But this doesn't explain why they are all going (ultimately) in the same direction around the gravity source. For example, why can't the object if captured in orbit go counterclockwise instead of clockwise (be it earth, the sun, or a blackhole in the center Of a galaxy). (Now thatI think about it I guess there are Warkendi planets revolving the opposite way as the rest as long as they are in a safe noncollision orbit.) And yes, I just realized that the issue of all objects revolving in the same direction probably isn't the same issue as  my question about the spiral pattern  of certain galaxies.)

But, we don't have to get into it again right now. I'm just saying not only do I generally not understand agent oranges answers I usually don't understand peoples' questions exactly. Because there are often assumptions in the questions that are undefined or ambiguous. Same with the answers for that matter, I can easily infer something that isn't meant due to my unclarified  or unwarranted assumptions. :-)

[DigitalPigSnuggler]

For example, why can't the object if captured in orbit go counterclockwise instead of clockwise (be it earth, the sun, or a blackhole in the center Of a galaxy).

It does both.  It depends upon your location while observing the orbit.

[Tarbaby]

Aren't you the clever one? :-)

It does both.  It depends upon your location while observing the orbit.

[Rudolf Zlabinger]

Dear Tarbaby,

the universe will stay a mystery to human being as long there is no model, whose ability to describe the manifold given by it is powerful enough to grasp the essence of real cosmology.

I am one of those rare people (in my opinion) looking for such a model, perhaps my "Discrete model of Cosmology" already in its pre native state  shows at least the tremendous power of mathematical structures we already have available to go a total new way.

If you like, read it, the aspects that will shown to you there are at least amazing.

I had a little error in my last contribution, as I named Onan instead of you, who told me, I should post in this topic.

I am sorry, that I have no more answers for you, but it seems they are nowhere in the presence, all the best, Rudolf Zlabinger

[Tarbaby]

Thank you, Rudolph. I must admit I was immediately curious when you said you were interested in a new cosmological model but the idea of a lot of complicated math makes my eyes glaze over. If you like you could start a thread just like this one so you could tell us about your model Or, if you're not familiar with thread creation let me know and I can create it. Just tell me the thread name you'd like.

[Rudolf Zlabinger]

Dear Tarbaby,

thank you for your help, I am experienced enough handling forums functions, the Topic is in General Discussions and I s named "A discrete model of cosmology".

Thank you again, and glad to see you in the thread soon, best wishes, Rudolf Zlabinger.

[Camazotz Automat]

AO, what a fine job you did on The Gabcast. I just now had a chance to listen to it.

It's easy to imagine you having your own podcast. The non-live format used by The General would be perfect for distilling astro-information into a short amount of time as you answered selected questions or just generally "spread the good news."  You've got the right voice and like The General, the authenticity and enthusiasm rings true/through and easily draws in the listener. I'm sure (Redacted) would consider pulling special duty in the field to provide the low down on the pagan antics of a local star gazing group:

We had awesome Jello shots and made jokes about Betelgeuse. It ruled. Completely. I also want to mention the cherry Celestron telescope we used for viewing. Evidently it was a prototype and the only one ever made because Celestron decided on a different design. This telescope was HUGE. It was light sage green. It had an almost military feel. Because of its size, it reminded me of the projection device used in a planetarium, with lots of solid tech utilized.  Lots of big black knobs to click it precisely along. The owner explained the optics, the rare earth blass lenses used in it, as being from Leica, that German company that makes high end cameras. The whole experience blew me away. A one of a kind telescope for a one of kind night under the stars.

If you were to ever pen a mainstream book, somewhat like Hawking's classic ABHOT, a podcast would be a satisfying method of advertising it.

As if you don't have enough occupying your time as it is.  hahaha

Once again. Fantastic job.

[zeebo]

AO, what a fine job you did on The Gabcast. I just now had a chance to listen to it.

It's easy to imagine you having your own podcast. ... I'm sure (Redacted) would consider pulling special duty in the field to provide the low down on the pagan antics of a local star gazing group ...

AO on the cosmos & (Redacted) on pagan star rituals?  Sign me up for the premium subscription package.  But, only if you include a segment called the Skeptic's Corner where a51d posits a contrarian question each week.   

[GeorgieForPresident2216]

Dear Agent : Orange,

to give special attention to your topic, that lead me to this forum originally by google, and by recommendation from onan, I will relate the issue to my "A discrete model of cosmology".

In the sense of my special model particles are partial graphs differing from empty space by density of edges between the elementary constituents of universe as vertices. The manifold possible is not restricted to a determined number of dimensions, as these have no correspondence in the model yet, and so there are most scary particles possible, as seen from the viewpoint of the model. Seen from there, the detection of more and more and also strange particles is of no importance at all.

The situation seems to be that of children, looking for and finding toys, and are fascinated at the end detecting the unrestricted possibilities of construction sets allowing to make toys as they can imagine. (You perhaps remember to Matador or PlayMobile and more...)

But this is the situation of science at now, and so let us stay curious, what they find next.

I will keep attention to your topic, best regards, Rudolf Zlabinger       

If I understand correctly, this sounds like a version of superstring theory, though I am not very conversant in that topic.  My personal poorly educated take on the Universe, which I think takes somewhat from string theory, is that the universe can be broken down into 'pixel' elements the size of Planck volumes.  The Planck scale is the limiting magnitude where quantum effects completely dominate so dimension on a smaller scale ceases to have any meaning.  These Planck-sized 'pixels' behave as manifolds (this part is sort of like string theory as I understand it) The manifold 'pipes' connect in three dimensions to adjacent manifolds in adjacent pixels, but the rest of the 'pipes' (dimensions) curve back on themselves and don't go anywhere.

My personal ideas on modelling a discrete universe go deeper than this but I think that is what is relevant to your post.   I actually believe space is an illusion created by the incremental movement of information from 'pixel' to 'pixel' in something I like to call Precedence Theory.  We interpret the rate of information transfer as the speed of light.  Sometimes pixels get 'stuck together' and we see that as quantum entanglement.  I can't comment on your thoughts about modeling particles because I don't have a deep enough command of quantum or particle physics.

[DigitalPigSnuggler]

I can't comment on your thoughts about modeling particles because I don't have a deep enough command of quantum or particle physics.

Your restraint in not commenting when you don't have good knowledge of a subject is admirable.  I sure wish that more people had your attitude when it comes to politics and current events.

[GeorgieForPresident2216]

Your restraint in not commenting when you don't have good knowledge of a subject is admirable.  I sure wish that more people had your attitude when it comes to politics and current events.

Given the rest of my hypothesis I'm not sure if you're being sarcastic or not but thanks .  I don't think you were but I probably would deserve it.

[DigitalPigSnuggler]

Given the rest of my hypothesis I'm not sure if you're being sarcastic or not but thanks .  I don't think you were but I probably would deserve it.

No, I was being serious.

[zeebo]

Here's the neat pic of that comet nucleus taken a few days ago by the Rosetta spacecraft.

http://apod.nasa.gov/apod/ap140807.html

And while you're at it, check out the next day's pic, of this cool spiral galaxy, oriented in a way that gives it some visual depth.

http://apod.nasa.gov/apod/ap140808.html

[area51drone]

Reminder everyone, tonight is the Perseid meteor shower.  Happy skywatching!

[zeebo]

Another APOD pic.  Just a cool nebula, because, well, it's cool.

http://apod.nasa.gov/apod/ap140802.html

[area51drone]

Another APOD pic.  Just a cool nebula, because, well, it's cool.

http://apod.nasa.gov/apod/ap140802.html

Would have made a great "Dark Matter" background image... very cool thanks for sharing.

[area51drone]

I just noticed that the new Cosmos series is available for streaming on Netflix for anyone who missed the original airings or wants to watch again.

[zeebo]

I just noticed that the new Cosmos series is available for streaming on Netflix for anyone who missed the original airings or wants to watch again.

Hey a51d and others, what was your overall assessment of it?  Were there any particular episodes that stood out?

[area51drone]

I thought it was good.   Too sum it up in just a few sentences, visually far more impressive than the original, but I don't think NDT is as good of a narrator as Sagan, so I still like the original more.  Near the end they get all "we're destroying the earth" on you, somewhere in between Sagan and Jim Sparks, which is distracting.   There is a lot of history in the show, which is fine, but sometimes I feel like there's just too much history and not enough "this is what it is, this is what we know and what we don't know."    It's worth watching, just don't expect to learn much if you watched the first series, or if you know more than the average joe (which I know you do).

That Great Courses series with Fillipenko that I pm'ed you about though is far far more interesting.   I'm looking forward to watching some of the other titles that I bought that are in the queue for me - Mysteries of Modern Phsyics: Time, Quantum Mechanics,  Skywatching, Superstring Theory, Particle Physics, Physics beyond the edge, and then a whole slew of math ones I bought.   The course on Hubble was awesome, and the Carroll Dark Matter and Dark Energy one was good too.    I'll try to post a brief review of each as I watch through the rest of them.   I'm sure I'll have some questions (as I do now on this series) for AO, but since he hasn't even responded to my last stuff I will have to hold off.     I can only hope AO gives us the low down on his work once he comes back from his time with the Kecks.   (j/k btw, who knows where he is!)

[DigitalPigSnuggler]

I thought it was good.   Too sum it up in just a few sentences, visually far more impressive than the original, but I don't think NDT is as good of a narrator as Sagan, so I still like the original more.  Near the end they get all "we're destroying the earth" on you, somewhere in between Sagan and Jim Sparks, which is distracting.   There is a lot of history in the show, which is fine, but sometimes I feel like there's just too much history and not enough "this is what it is, this is what we know and what we don't know."    It's worth watching, just don't expect to learn much if you watched the first series, or if you know more than the average joe (which I know you do).

That Great Courses series with Fillipenko that I pm'ed you about though is far far more interesting.   I'm looking forward to watching some of the other titles that I bought that are in the queue for me - Mysteries of Modern Phsyics: Time, Quantum Mechanics,  Skywatching, Superstring Theory, Particle Physics, Physics beyond the edge, and then a whole slew of math ones I bought.   The course on Hubble was awesome, and the Carroll Dark Matter and Dark Energy one was good too.    I'll try to post a brief review of each as I watch through the rest of them.   I'm sure I'll have some questions (as I do now on this series) for AO, but since he hasn't even responded to my last stuff I will have to hold off.     I can only hope AO gives us the low down on his work once he comes back from his time with the Kecks.   (j/k btw, who knows where he is!)

I haven't kept up with it so forgive me if they're already doing it, but I think a good way to trade off of the past would be to use old clips to show what we used to believe, and then explain what recent discoveries have shown using the new guy.

[area51drone]

I haven't kept up with it so forgive me if they're already doing it, but I think a good way to trade off of the past would be to use old clips to show what we used to believe, and then explain what recent discoveries have shown using the new guy.

There wasn't much that has changed between the old and the new.  Most of it is history from long ago, when physics and astronomy were in their infancy.   Most of the newer stuff is still a hundred years old, so Sagan had it right even then.   Has there been any real major physics breakthroughs in the last 100 years?

[zeebo]

There wasn't much that has changed between the old and the new.  Most of it is history from long ago, when physics and astronomy were in their infancy.   Most of the newer stuff is still a hundred years old, so Sagan had it right even then.   Has there been any real major physics breakthroughs in the last 100 years?

It does seem like physics, at least in the last half-century if not longer, has been more incremental than revolutionary.  Alot of the huge leap stuff - namely relativity, quantum mechanics, and the expanding universe discoveries - were done largely in the early 20th century (with of course many iterative findings later).

String theory would be hugely revolutionary, if confirmed.  But it seems to be quite difficult to prove.  It also seems that in general, when it comes to physics, we're becoming limited by the scale of the projects required to further the observational science. 

The discovery of dark matter & dark energy seem pretty huge, but they're still such unknowns.  The Higgs-Boson was pretty big.  I'm sure I'm missing stuff but it does seem like kind of a tough time for big breakthrough physics.  (But I'm sure Agent Orange is cooking something up in some lab somewhere, maybe his own mini-wormhole experiment or something cool.)

[GeorgieForPresident2216]

It does seem like physics, at least in the last half-century if not longer, has been more incremental than revolutionary.  Alot of the huge leap stuff - namely relativity, quantum mechanics, and the expanding universe discoveries - were done largely in the early 20th century (with of course many iterative findings later).

String theory would be hugely revolutionary, if confirmed.  But it seems to be quite difficult to prove.  It also seems that in general, when it comes to physics, we're becoming limited by the scale of the projects required to further the observational science. 

The discovery of dark matter & dark energy seem pretty huge, but they're still such unknowns.  The Higgs-Boson was pretty big.  I'm sure I'm missing stuff but it does seem like kind of a tough time for big breakthrough physics.  (But I'm sure Agent Orange is cooking something up in some lab somewhere, maybe his own mini-wormhole experiment or something cool.)

I agree with everything you said.  It's not so much about what we believed in the 1980s being wrong.  Science is objective and what survives the rigours of the scientific method tends to stick.  Now I suppose it's more a matter of refining what we already know, but most of the modern breakthroughs probably don't appear very dramatic or revolutionary to anyone except scientists in the field.

Scientists have done some important things since Sagan's series though.  You've mentioned string theory which was, I think, at best in its infancy at that time.  And as you've mentioned the discovery of the Higgs-Boson has all but confirmed the Standard Model of particle physics which I think was still fairly uncertain back then. 

I think the most important discoveries include pinning down the age of the universe and discovering it is nearly perfectly 'flat', which means it will most likely expand forever.  These seemed to be the holy grails of cosmology at the end of the 20th century.  I think we also know a lot more about the large scale structure of the universe, and have brilliant photographs thanks to Hubble which Sagan probably could only dream about back then.  Scientists have discovered the universe is accelerating in its expansion, a complete paradigm shift which led to the discovery (or should I say invention) of the dark energy you already mentioned.  We've discovered extrasolar planets and evidence of ancient rivers and lakes or oceans on Mars.  But the thing I would add to your list is both the inception of Inflation Theory, and its apparent confirmation early this year.  This has many consequences including (to the best of my understanding):  supporting the notion that Universe is vastly, vastly larger than the little area we can see; the conclusion that the Universe may have zero net energy (which includes matter) -- ie/ we didn't get something from nothing, we got nothing from nothing; observational verification of Einstein's gravity waves; and the possibility of a multiverse.

I think that your point that none of this invalidates anything we knew back during the original Cosmos series is a good one.  You were talking more specifically about the laws of physics.  The principles of physics haven't changed and were just as solid back then.  These new discoveries probably won't have any practical relevance for a very long time.

[zeebo]

...We've discovered extrasolar planets ...

I'm not sure if this is considered physics or more just general astronomy, but it's for sure a good example of an area we've made great progress in, just in the last 20 years or so.

I think the first one was found sometime in the mid-90's and now, we've got thousands known, and from that we can infer something like 100 billion in the Milky Way alone.  It makes me think that all those artist renderings of planets on my sci-fi book covers really do exist out there somewhere.   

[GeorgieForPresident2216]

I'm not sure if this is considered physics or more just general astronomy, but it's for sure a good example of an area we've made great progress in, just in the last 20 years or so. 

I think the first one was found sometime in the mid-90's and now, we've got thousands known, and from that we can infer something like 100 billion in the Milky Way alone.  It makes me think that all those artist renderings of planets on my sci-fi book covers really do exist out there somewhere.   

No, you're right.  I was going back to the theme a few posts ago and straying from your post which dealt more specifically with physics.

Yeah, it's quite incredible when you look back on it.

[area51drone]

I could be wrong, but most advances in physics, astrophysics, etc have just been physical validation or disproving of old theories, and that's what I was talking about.  String theory I would agree with Zeebo might be the newest thing since then, but even it was theorized in the late 60's, and Cosmos aired in 1980, so there was at least a decade of talk about it.   But there is no doubt people knew or believed exoplanets existed, and dark matter, if not called dark matter, was certainly something that they had an inkling about a long time ago (Jan Oort, 1932).   

And, the show is called "Cosmos" not just physics or astronomy, but also biology etc.   The biology episode even included the evolution animation from the previous series.

Anyway... worth watching regardless.

[zeebo]

...The biology episode even included the evolution animation from the previous series.

That was a bitchin' animation, especially with that soaring music paired with it (at least in the old series).  Somehow Sagan and his production team there was able to get across big concepts without getting too bogged down in the details. 

There was one episode near the end, where he talked about the concept of memory.  He went from DNA (genetic memory), to the brain (our literal memories), to books (collective memory across generations).  If I remember right he ends it with the disc on Voyager, which is a kind of memory of our whole planet. 

The concepts were rooted in science (e.g. genetics, neuroscience, linguistics, space exploration), but illustrated in a way that highlighted the big picture meaning of it all.  Great stuff.