Getting my head around Astro Physics.

[Suzy]

Hello to everyone in the science forum :hi:

I would normally post this in the "Books & Media" section, but instead I thought I would throw this one across the Science section as I've added some extra bits. Carl, if I haven't explained myself well enough, go easy on me, but I welcome clarification. I, after all, do not talk the science "lingo", for I am a mere beginner trying to grasp a very complicated area in science. Actually, I guess that goes to all you wolves here in the science section too :lol:. The Science Forum is highly informative and entertaining (!) area within IIS, but blinking heck, can be be a scary one too. :lol:

I find String Theory fascinating, but the the problem with me is I am the worst at maths, and here I am trying to learn physics. I'm trying to run before I can walk, and therefore I've had to go back and try and grasp the basics of physics. A lot of this stuff just won't stay in my head because I can't break it down to comprehend it, all the same I enjoy learning about it. On top of that, I'm now trying to grasp how stars work so am studying that as well. Then, every clear night I can get (rare of late), I am there with my telescope observing. Now, I'm also trying to learn to sketch. My brain is going into overload. :help:

It is just incredible how diverse an area of Astronomy is. I've had to buy so many different types of astro books (and they are on the expensive side) to try and cover this area.
I've just added a new one to my collection, Patrick Moore's Practical Astronomy Series, "Physics Made Easy" by Mike Ingliss. He said in the book review, that learning the maths exercises given in the book was purely optional and the reader can skip past it. I reckon I'll will be skipping those bits.

For the beginner learning this stuff, it gets even more confusing when there are all these different theories out there and what you have just learned can change as quickly as picking up another book. Be it different perceptions of current theory or new information that comes to hand (floodsville for the latter).
For instance, with string theory, they talk of 10 dimensions, but another source tells me 11. Hawkins seems to think the universe started with a black hole. If I have misinterpreted this, please let me know, but that's what I took from it. And then there are Branes. Branes weren't mentioned in the show "Hawkings Universe". I have his book (yet to read), "A Brief History of Time". Is it mentioned in there?

The other day when I was watching the new Foxtel series, "How The Universe Was Made", the episode being "Big Bang". I learned quite a bit. I watched the episode twice, and then the third time I hand wrote out half the show. I'm embarrassed to say, that by writing it down in simple english in the way that the presenters explained it, as opposed to the complicated word use in books, I can grasp it sooo much easier.
Theoretical science is definitely a confusing one to learn, especially for the beginner. Some stays in my head, and some I forget.

In this episode, they go on talk about, and I quote all of the following from the Foxtel show mentioned above:

The Perfect amount of gravity. If it's too weak, no galaxies can form. too much, and everything will end up in black holes.

A fraction of a second after the big band, a shockwave of energy erupted and expanded the universe in all directions at incredible speed. "We think that in a millionth, of a millionth, of a millionth, of a millionth of a second, space expanded by a factor bigger than a millionth, of a millionth, of a millionth, of a millionth times. Faster than the speed of light, scientists think that it took less than a millionth, of a millionth, of a millionth, of a millionth of a second for the universe to expand from the size of an atom to a baseball. It's like a golf ball expanding to the same size of Earth in the same amount of time.

Regarding mater & anti matter.... Equal amounts will inialate back into pure radiation, and there will be no stars and galaxies. For every billion particles of anti matter, there is a billion and one of matter. That was the moment of creation. The one extra particle of matter in each little volume survives enough to form all the matter that we see in the stars and the galaxies today. One in a billionth may not sound like much, but its enough to build a universe. Michlo Kaku went onto say, "We're the left overs, so believe it or not, everything you see around you, the atoms of your body, the atoms of the stars are nothing but left overs. Left overs from this ancient collision between matter and anti matter." Lucky for us, there was enough left over to make all the stars and planets. And the universe is till less than one second old.

In the first three minutes, everything interesting that was going to happen, happened.

Crikey all this stuff is certainly awesome, but yet so much to take in. I wonder if most amateur astronomers get into learning the astro physics side of things. Be kind of hard not to - wouldn't it... :question:

Kind regards,
Suzy.

[CraigS]

Hey Suzy;

Good to see you having a go and posting here. Better this way than yesterday's way, huh ? (I'm still cracking up !!).

Tricky stuff trying to get into the Science of it all, but I am so happy that you are going along with your enquiring mind and intuition. Good onya !

I'm no expert either, .. so we go at it, together.

I guess there are lots of different interests here at IIS, and it just seems that my key interests lie in attempting to understand the big picture. I wish I could give you some easy tips but I'm not sure I'm the best to do this. I'd love to help out in the process, however.

Cheers & Rgds

[renormalised]

I can tell you now, Suzy, the maths is hard for all of us, regardless of how well we understand the theory:)

What you need to do is take things one at a time...start off with the simple stuff...Newton, Maxwell, etc...i.e. learn all about Classical physics (e.g. atoms, light, gravity etc), before you get into quantum mechanics, relativity, supersymmetry, string and m-theory etc etc. That way, you'll find it much easier to understand the harder aspects of the subject.

The way you're approaching it by writing down what they say is good. Keep those notes and read them as often as you can. It'll stick eventually:)

A correction....it's the other way around...for every billion particles of antimatter, there was one billion and one of matter:) Otherwise, we'd all be antimatter now:)

[astroron]

Suzy, that is some awesome post, I will be following this thread diligently:thumbsup:
If you keep going with getting more and more books, you will soon equal the library of Alexandria :lol:

[CraigS]

Great advice Carl.

Classical mechanics - Gravity is a good place to start. Newtons laws is kind of where Physics began. They covered the general aspects lightly in 'The Universe' doco in the episode which traces the history of physics. Come to think of it, that's another good way to get into it. I remember my physics textbooks in High School took the history of Science tack. Problem with those texts I found, was that there was too much history and only a puny amount of theory/maths describing Kepler's laws etc. And yet, that's what the exams were about.

Wiki is a good place to form questions about it all. I find when I get a moment, if I go there, something always comes up in my mind from past discussions here, that can result in hours of reading up in order to understand some topic. That then seems to lead into reading research papers, and talking here.

Hope this is helping Suzy .. its a difficult one to tackle. I'll go quiet for a while .. let others make some suggestions.

Cheers
PS: The 'In-the-News' threads we all post, are also a 'softer' approach to it all. The journos always write stuff that I find doesn't make sense which then, with further research, leads to a better understanding of the topic and surrounding issues.

[renormalised]

I couldn't find many books on basic physics that were good enough for beginners such as yourself, but try this one....Conceptual Physics (http://www.fishpond.com.au/9780321684929)

It's as near to a high school text as I could find.

Here's the supplementary problem book to go with it....Problem Solving for Conceptual Physics (http://www.fishpond.com.au/9780321662583)

[CraigS]

Just had a thought..

There are a few retired high school Science teacher types who are IIS members.

Love to get their input on this one.

Cheers

[Suzy]

Aah, yes I see that now, was too busy watching the awesome graphics on matter and anti matter having a wing ding as I was writing it down. I have gone back and watched that particular segment again, and that part is clear to me now. I will edit that bit in my post so I don't confuse people. Thanks Carl.

[Suzy]

Thanks Ron. :)
I have to stop buying books now so I can digest all this stuff. :confused2:

Craig don't go quiet on me!

[renormalised]

<<<Craig collects the sound of his voice>>> "Hmmmmfff, hmm hmmm hnfff, hmmmnff!!!":):P:P:P:P

[CraigS]

Perhaps another way to tackle this is to follow the story … here goes .. Carl .. please correct me where I stray (.. as if I have to ask :P) ..



… a computer model based on the fundamental universal parameters of Physics.



This is Big Bang Theory .. followed by Inflation theory … The tiny-ness of the dimensions results from running the current expansion observed in the present day universe, (Hubble's Law), backwards in time. If you do that, things get small. As things are compressed smaller, they get hotter (Laws of Thermodynamics). When they get to Planck dimensions (the smallest anything can theoretically ever get), they get so hot the energy is unimaginably huge and likely to be unstable. Something then happened (not exactly sure what .. perhaps Symmetry Breaking - (Quantum Theory).

Is this approach helping, or adding to confusion ?

Cheers

[renormalised]

As I advised earlier, it's best to get a good textbook on the subject and learn from that. You need to have a good handle of the basics of physics before you try and understand the rest.

[CraigS]

You wrote that while I was constructing my work of art below !!

I call foul !!
:P:)

[RobF]

Maybe there was a bit more anti-matter after all, and now because we're anti-matter, the real matter appears to be anti-matter? :screwy: :question:
(my head's hurting now....)

I find it fascinating try to figure out how you could even start to conceptualise multiple dimensions, let alone 11, and the concept of the universe existing on membranes in higher dimensional orders creates so many interesting possibilities.

Maybe our grandkids will be doing higher dimensional calculus in their heads and on their quantum-computing IPhone mark X's !.... :lol:

[Suzy]

I think I already have a handle of what happens in that area, let me see If I have it right...

Yes, understand that things were tiny at the start. When matter and anti matter sorted themselves out, they had to cool down and slow down, so particles could connect into atoms.

[renormalised]

The first part, Craig, was worked out via theory and experimentation long before they had computers to model it. There is basically 6 or so fundamental numbers which, if they were even ever so slightly different, we wouldn't be here to be talking about it.

[CraigS]

Bert made some great comments the other day about the human brain and where its come from. Lets face it, all of these theories and explanations have come from within the darkest recesses of scientists' brains … and before that .. from a puddle of goo !!

Classic stuff !!
:)
Cheers

[renormalised]

You need a good imagination, which is the main requirement with any science:):)

Then you need to be able to visualise it:)

[Suzy]

The reason I have posted this here, is after watching (and writing down) and re reading the "Big Bang" episode, I found it much easier to understand. Whilst I appreciate the education in books, nothing beats the simple talk of explaining things - it's pricless in my opinion - helps the understanding process of books. I know I should go back to the drawing board on physics, but at the moment, I am far too impatient. For example, I want to know why a star does what it does, without having to pick up a 300 page book on physics for dummies" and one week later after much reading, getting a question answered. Instead, I would pick up my book on stars and work my way thru trying to understand. That's where my frustrations lay. I have some good books on physics, I will work through them. I realise, I have much in physics to learn, and I can never know nor understand the full extent of it (my brain is not geared that way). For the time being basic physics will have to carry me through to basic questions I have. I do realise I'm trying to run before I can walk. I am in awe in what I see through my telescope, I pretty much want to relate to what I see on a better level of understanding. This new series on Foxtel "How the Universe Was Made", has really made me put my thinking cap on, even more so than before.

Today, on ABC radio, Richard Fidder (if i got his name a bit wrong, you probably know who I'm talking about anyway), had someone on there explaining all about the big bang. Priceless timing. I could really connect and understand what he was talking about. So much easier with simple talk, like I said before.
He went on to talk about, not just why planet Earth is so special (including the moon's affect on Earth being special), but how the Universe being born in itself is fluke and special. All these stages, had to get it right. That put a lump in my throat.. I only ever hear about "Earth being special". He put it in great perspective.

There are a couple of questions within my thread if someone would like to have a crack at them at some stage. The 10 and 11 dimensions, and also Hawkins theory on the big bang.

Meanwhile, I don't expect you'll to be Einsteins and give me all the answers to which I seek- the big bang theory and string theory is highly involved. Just simple discussion can lead to lots of learning.

[renormalised]

Fire away, Suzy:)

[renormalised]

This will explain to you in simple terms why the 10-11 dimensions. If you run across any problems, post them here and either Steven or I will explain them for you:)

Supersymmetry (http://en.wikipedia.org/wiki/Supersymmetry)

[Suzy]

:confused2: :P :rolleyes: :confused2: :screwy: :mad2: :lol::lol:

[renormalised]

It's not that bad!!!!:)

Geez, if I can understand that, then you should be able to:):)

[CraigS]

Need a translator ??
:):)

[Jay-qu]

Hi Suzy,

If you are interested in string theory but dont have much of a background in maths, I would suggest picking up a book by Brian Green called "The Elegant Universe". Or if you prefer there is a documentary similarly named.

As far as I remember this book did not require much understanding of maths. Most pop-sci books on these subjects are fairly light on the details since since to go any deeper would require a degree for a start..

You have already taken the best step and that is to discuss things you dont understand with others, so keep that up and you will get there.

J

[sjastro]

Perhaps the best way of understanding String Theory without being bogged down in the mathematics is to understand the reason for it's existence.

Here is an introduction to String Theory in terms of the lead up theories
Special Relativity, General Relativity, Quantum Mechanics and Quantum Field Theory. The mathematics is only in passing. (Let the Physics and Applied Maths post grads do the suffering):).

A few good lines in the presentation, add gravity to Quantum Field Theory and you get a train wreck.

http://www.slimy.com/~steuard/research/StringIntro/slide01.html

Hope this helps

Regards

Steven

[snas]

Rob, I've also wondered about this too. Who's to say that we are matter or antimatter. All we are is just that bit which exceeded its opposite at BB.

Steve and Carl, is it that simple? Or if we are really antimatter and not matter, does that fundamentally change the way things are for us? Do you have any comments.

Steve, I had a look at your link Steuard Jensen's discussion on String Theory. I've never been able to conceptualise the idea of any more than the 4 "obvious" dimensions, but his very simple explanation of the man and the ant walking on the tightrope allowed me to at least see how extra "invisible" dimensions may occur.

Stuart (biologist trying to be physicist :eyepop:)

[higginsdj]

Damn, you have jumped into the deep end. Here was I struggling with calculus and Solar System Dynamics thinking that was hard! Good luck.

If you want to improve your math and general physics, don't forget iTunesU. I've downloaded gigabytes of lectures and starting to make sense of derivitives, differential equations and integrations (well, just derivitives at this stage - I did fail maths at school - 30 years ago)

Cheers

[sjastro]

There are four properties that differentiate matter from it's mirror image (antimatter).

(1) Charge
(2) Magnetic moment
(3) Parity
(4) Helicity or handedness.

Charge is obvious, parity and helicity relate to the mathematical symmetries of particles and antiparticles. So for example if a particles intrinsic spin and linear momentum are in the same direction then the particle has a positive helicity where as the corresponding anti particle will have the instrinsic spin and linear momentum in opposite directions (negative helicity). All neutrinos are left handed, all antineutrinos are right handed.

As far as an absolute test to differentiate matter from anti matter, the magnetic moment is the key. Even a particle with neutral charge such as a neutron has a magnetic moment.

If you pass a neutron through a magnetic field it will always deviate in the same direction in the field. The antineutron will deviate in the opposite direction. Same with the proton/antiproton.

We know we are made from matter, just break down the constituent nucleons that make up the matter pass it through a magnetic field and you have your answer.:)

Regards

Steven

[CraigS]

Is there a degree of conventionality in this ?
I guess if one applies tests for all of (1) to (4), then maybe there's no definitional issues (?)

… interesting ...

Cheers & thanks for a great answer, Steven .. very clear ..

[renormalised]

I think in this case, Steven, their argument on matter/antimatter is more a difference of opinion on what you define as matter and antimatter. Being a case of philosophical semantics..."what do I think I am". "Antimatter" people might think they're ordinary matter and call us antimatter, which actually would be true from their point of view:)

[orestis]

Very Interesting topics Suzy,

I was thinking about how well all this technical stuff is communicated because i read and see scientists using all this technical jargon that we cannot understand but if they new how to break it down and explain it well then maybe we could understand.

Such as i was watching insight on SBS(i think) the other week or so and there was a Climate scientist in the studio taklking to a bunch of climate skeptics and he communicated very well and used Easy to understand analogys.

One of the best communicator was our beloved Carl Sagan,I only wish we had more like him now.

Regards Orestis:thumbsup:

[renormalised]

There are ways and means of breaking down the jargon into easy soundbites, but it can be difficult getting across the essential kernel of knowledge without diluting it that much it's basically useless to anyone. Lots of science gets misunderstood and misinterpreted because of this and it's where the public get led astray all too often.

[snas]

Steve, thanks for your answer. I see the beautiful "simplicity" to your answer. But then there is Carl's answer from a more philosophical standpoint which also has a certain simple beauty as well.

Hmmm, thanks guys, back to biology now.

Stuart

[sjastro]

The conventionality in this case groups matter/antimatter into symmetrical pairings.

For example.

Protons/Antiprotons:- (1) and (2)
Neutons/Antineutrons:- (2)
Neutrinos/Antineutrinos:- (4)

For (3) If matter has +1 (or -1) parity then the corresponding antimatter has -1 (or +1) parity.

Regards

Steven

[sjastro]

Antimatter people are very much in the minority so their opinion doesn't count (isn't that how democracy works:))

The fact that we can differentiate between matter and antimatter allows an argument on semantics.

It reminds me of a "discussion" I once had with a smart a*se know all kid who asked me how I could tell the difference between a piece of paper made of ordinary matter from and one made of antimatter. I said to him if you write your name on the ordinary piece of paper and looked in the mirror you would see a reversed image. Write on a piece of antimatter paper (and assuming you don't annihilate yourself in the process), the image isn't reversed. That completely confused him yet it was a subtle lesson of the role of parity in matter and antimatter.:lol:

Regards

Steven

[orestis]

Very true Carl,
There a lot of times when this happens.Too often it seems on TV the media make all the science stuff too sensational.

regards orestis:thumbsup:

[Jay-qu]

Just to clarify this point a little.. You can have left and right handed electrons, just as you can have left and right handed positrons.

Neutrinos are an altogether different matter since it is no known if they are Dirac fermions (like electrons) or Majorana fermions. If they are Majorana fermions they would be their own anti-particles - like photons. The standard model of particle physics assumes neutrinos to be Dirac fermions.

Since the Weak force only interacts with left handed particles and right handed antiparticles and so if neutrinos are Majorana fermions then neutrinoless double beta decay would be possible.

This is all important because we know neutrinos have mass, but we dont know how to theoretically express the origin of their mass. Trying to use the Higgs mechanism (as is used to give all other particles mass) breaks gauge invariance - something held in very high regard amongst physicists. There are other mechanisms for explaining neutrino masses such as the see-saw mechanism, but it depends on the particulars of how many neutrinos there are and whether they are Majorana or Dirac fermions. A plus side to the see-saw mechanism is that it requires a heavy sterile neutrino which is a candidate for dark matter.

Hope I havent rambled too much..

[renormalised]

Yep, they all went off with a bang, years ago:D:P:rofl:

Although minorities aren't supposed to be discriminated against in this day and age...figuratively speaking:P:D

[Suzy]

Just found out the answer to this one.
The 11th dimension is TIME. 10 dimensions + time. Doh! :rolleyes: The string theory model doesn't work with anything other than these 11 dimensions.

Thank you all, for your help and encouragment. I'm very grateful. :)

[CraigS]

Actually, I was just looking through the link Steven recommended on string theory in this thread and this guy says:

… plus one for time = 11 dimensions. [EDIT: oops 9 + 1 = 10 .. got a bit ahead of myself there].

Not sure I've ever heard of this bosonic version of string theory, though.

Witten's version of M-Theory calls for 11-dimensions which unites all five competing string theories (and supersedes them).

Cheers

[Suzy]

Spot on :thumbsup: exactly as I understood it. In the Foxtel show "Visions of the future", presented by Professor Kaku, he went on to say that this model will only work with this amount of dimensions- the others didn't cut it.

You would know this already, but for those who don't, the M theory name was invented by Witton and it stands for "magic".

Did you watch that series Craig? It was on recently. Brilliant!

[CraigS]

Suzy …

I don't know what was up with Kaku lately, he's been coming up with some pretty wild stuff .. I think commercialism may have caught up with him. I did see "Visions of the Future". It was pretty cool, though.

Ed Witten himself says: "that the interpretation of the M can be a matter of taste for the user of the name." In Elegant Universe they interview Witten about this and he says it could be magical, mystery (or a few other things), but its all according to taste. I think this is his way of distancing himself from it all .. given that even he says no-one understands it yet. I think he's spent the last few years coming up with new mathematics to deal with the multi-dimensionality of it all. I'd say he's the only one who could probably explain part of it, in our lifetimes.

But aside from the detail, I still don't get this 26 dimensions stuff in boson string theory ..!

Cheers
PS: Thanks for picking me up on my arithmetic 9+1=10, right .. not 11 ? Doh !! :)