BBC2 tonight 9.00

[rory]

nice thread guys. i must say i was lost on most of the programe,as im not accademic at all. 75% was lost on me, but i was fascinated all the same.

rubbing diamonds altering its state and making things move around the otherside of the cosmos, i dont know weather to gasp or snigger.

fair play brian ,wish i understood more :icon_eek:

[ncjunk]

Very good program for mainstream tv. Use of Celebs for entertainment value whilst getting across a couple of points. There's not really a lot more you can ask for in a one hour program.

I'm just glad the bbc decided to do it rather than another Antique road bargain trip sale whatever show!

[Astro Imp]

I enjoyed this very much but as has been mentioned several times noticed that he stressed that no two electrons could occupy the same energy state and then proceeded to illustrate just that with the schematic of the oxygen atom without any explanation. Thanks JulianO (link #47 above) you have cleared that point.

As BC was labouring the point that the modern world was dependent on quantum physics a follow up program illustrating some of this would be useful.

[Anweniel]

Seems a lot of vitriol directed towards Dr. Cox and I'm not entirely sure why. Having watched the program I agree the use of celebrities was rather mundane and the likes of Jonathon Ross did little to add intellectually or to add any point to the content. However, looking at what for most of us is quite a heavy subject (considering Quantum Physics/mechanics is only really covered in HE and therefore only privvy to the top 2%ish of the nation - excuse me if my figures are out of date!) but we live with a heavy exposure to these 'celebrities' and its unsuprising to see them appear for ratings purposes I mean really anyone surprised by this???

All in all I enjoyed watching it and I do not think (or at least I hope to believe) that it all wasn't over my head! I don't think you can judge something that was aimed at a broader audience against factual content or something like a college syllabus. I found it went a good pace covering some more interesting points and singing James May's hands for amusement really to break up content makes such content easier.

Everybody is a critic and its easy to be, personally I enjoyed it for what it was an entertainment program whos subject matter was something I enjoy discussing/reading about.

In response to Chiltonstar, I believe the implication was correct that by exciting one electron theoretically the others are equally excited and so as to not occupy the same space all electrons in the universe equally excited, not just those of the atom. I think logically speaking and we see it on all other forms of energy that it gets dissipated (or rather transferred to another form by external factors). Certainly I think the implication is contrary to how most of us would logically assume but if as he stated the path of the electron had taken it to the andromeda galaxy and bake then surely every electron of every atom it passed had to be excited, and every electron from those particles the same etc etc until every electron in the universe was affected. Of course these figures are the subject of theory and the fact we couldnt ever hope to possibly check every electron in the universe or have a datum and how infinitissimaly small the excitement is would be immeasurable to our capabilities I would assume, so in theory is where the idea will likely remain ( and remain disputed no doubt!)

Feel free to put me right but this is how I understand it

Don't like to disinform but hope this helps in some way

[JulianO]

I don't have any vitriol to BC at all. I'm very glad he made the attempt, but I think it could have been done better. Some of the celebrities were put to good use, the rope swinging and so on, but the maths was a bit cringing, and taught us nothing. Two minutes of explanation (which Jim tried to do but got lost) I think would have been a worthy addition.

[kirkster501]

Not that it matters but I retract my comment about BC being patronising. He was really good last night and inspired my son who is doing his A levels no end.

Well done Brian.

[ixalon]

Yes, same here. His comments about the Pauli Exclusion Principle has raised similar questions across several forums. It is true within a single lump of metal, say, or crystal. But I'm sceptical whether it is true for every electron in the universe. But then it's a long time since I did quantum theory. It may be one of those things that is strictly true, but is predominantly dominated by local effects.

Just watched it and this was the one bit of the show that made me head to Wikipedia for some clarification - can't see anything out there suggesting the exclusion principal applies outwith an atom (though am in a train so it was far from an exhaustive search!)

I can understand how it could affect a molecule/crystal via its covalent bonds but can't see how the state of an electron can affect anything non-local (e.g even through a vacuum?)

Would love someone to explain it!

In response to Chiltonstar, I believe the implication was correct that by exciting one electron theoretically the others are equally excited and so as to not occupy the same space all electrons in the universe equally excited, not just those of the atom. I think logically speaking and we see it on all other forms of energy that it gets dissipated (or rather transferred to another form by external factors). Certainly I think the implication is contrary to how most of us would logically assume but if as he stated the path of the electron had taken it to the andromeda galaxy and bake then surely every electron of every atom it passed had to be excited, and every electron from those particles the same etc etc until every electron in the universe was affected.

Wondered about this too but then don't the interference patterns illustrated by the double slit experiment suggest only electrons in the physical path interact in such a way? Otherwise would it not be the case that all the other electrons in the universe (which may be crossing the path of the generated electrons) would also interfere? Maybe they do, but just not in a way that affects this particular experiment?

I've possibly got the wrong end of a very small stick here :-)

[kirkster501]

Just watched it and this was the one bit of the show that made me head to Wikipedia for some clarification - can't see anything out there suggesting the exclusion principal applies outwith an atom (though am in a train so it was far from an exhaustive search!)

I can understand how it could affect a molecule/crystal via its covalent bonds but can't see how the state of an electron can affect anything non-local (e.g even through a vacuum?)

Would love someone to explain it!

My take on what he was saying is that the Universe is a closed system and as such one tiny event at one energy level can affect an electron at the other side of the universe. In principle at least.

We can never truly measure this because the act of measuring affects what it is we are trying to measure - i.e. the Heisenberg uncertainty principle.

Then again I may be talking cobblers.... a long time since I did my physics at uni - too long...!

[Skybrowser]

As a Maths & Physics Graduate, admittedly from many years ago, I followed the presentation fairly easily, but my wife did not. But that's not the point. Brian Cox is a passionate and entertaining scientist. He has a good way with an audience and whilst the calculations were lost on Jonathan Ross, he is obviously a huge fan as he had what looked like his wife and son in the audience with him.

What I like about Brian Cox is that he is attempting to bring science to the masses. Pauli, Feynman (legend) and others would be well pleased. I never watch the Sky at Night these days as it pains me to see SPM in such poor health, hanging on to the programme and good luck to him but the whole programme needs a makeover again and new presenters, not Chris Lintott either. I find his style boring.

As for last night's programme, he shouldn't have said the diamond could jump out of the box as although it's possible to "prove" it can, it can't.

[onesmallstep]

Hi

I post a TV listings text file each week that highlights SciTech TV and radio programmes. See my threads in the Heads UP section.

HTH!

[astro mick]

Did i hear that right.(If electrons cant occupy the same place,then by rubbing that Diamond it shifts every electron in the Universe.)

Cant get me head around that!!!!

Does that mean they are all in contact, and just bump each other on.Even to distancies billions of light years away.This cant be instant because of the confines of the speed of light.

Or have i missed something,as my head is still spinning.

Mick.

[ixalon]

Mick, he did indeed, to (extended) quote the subtitle file:

Pauli's principle says that identical electrons can't occupy the same energy level. This is an absolute requirement. So it also means that electrons will avoid each other at all costs. And that, it was proved, is the actual reason that I don't fall through the empty atoms that make up the floor. That's ultimately what gives the illusion of solidity to the empty world of atoms.

And if you think a little bit more deeply about it, then this throws up a bewildering conclusion, and it's this. The Pauli Exclusion applies to EVERY electron in the universe. Not just every electron in a single atom, or a single molecule. And this leads to a bizarre conclusion. The particles that make up this diamond are in communication with particles everywhere. Inside all of you, and inside the atoms in the furthest corners of the universe.

Let me explain that a little bit more. The Pauli Exclusion Principle says no identical electrons can be precisely the same energy level. What if you have more than one atom? For example, in this diamond there are 3 million billion billion carbon atoms. So this is a diamond-size box of carbon atoms. And the Pauli Exclusion Principle still applies. So all the energy levels in all those 3 million billion billion atoms have to be slightly different in order to ensure that none of the electrons sit in precisely the same energy level. Pauli's principle holds fast.

But it doesn't stop with the diamond. See, you can think of the whole universe as a vast box of atoms, with countless numbers of energy levels all filled by countless numbers of electrons. So here's the amazing thing - the exclusion principle still applies, so none of the electrons in the universe can sit in precisely the same energy level. But that must mean something very odd.

See, let me take this diamond, and let me just heat it up a little bit between my hands. Just gently warming it up, putting a bit of energy into it, so I'm shifting the electrons around, some of the electrons are jumping into different energy levels. But this shift in the configuration of the electrons inside the diamond has consequences, because the sum total of all the electrons in the universe must respect Pauli. Therefore, every electron, around every atom in the universe, must be shifting as I heat the diamond up, to make sure that none of them end up in the same energy level. When I heat this diamond up, all the electrons across the universe instantly but imperceptibly change their energy levels.

Pauli's principal seems to actually state "two electrons, and more generally two fermions, cannot have the same quantum state (position, momentum, mass, spin)".

So, I suppose, considering an electron could be anywhere in the universe (though the further away, the less likely it is to be), and within this area, there can't be another electron with the same momentum, mass and spin, i.e. changing the state of an electron has a higher probability of affecting a local one, but could still affect one elsewhere in the universe.

That sort of makes sense to me... *head explodes*

[Reggie]

As a Maths & Physics Graduate, admittedly from many years ago, I followed the presentation fairly easily, but my wife did not. But that's not the point. Brian Cox is a passionate and entertaining scientist. He has a good way with an audience and whilst the calculations were lost on Jonathan Ross, he is obviously a huge fan as he had what looked like his wife and son in the audience with him.

What I like about Brian Cox is that he is attempting to bring science to the masses. Pauli, Feynman (legend) and others would be well pleased. I never watch the Sky at Night these days as it pains me to see SPM in such poor health, hanging on to the programme and good luck to him but the whole programme needs a makeover again and new presenters, not Chris Lintott either. I find his style boring.

As for last night's programme, he shouldn't have said the diamond could jump out of the box as although it's possible to "prove" it can, it can't.

It wasn't possible to prove though was it? It's a probability that you will have to wait that long but you couldn't possibly be there to witness it? So you can only suggest it will happen but not actually prove it with something that big? Whereas with nanoparticles you can prove it in, for instance, the touchscreen tech I linked to in a previous post.

Got to agree about Chris Lintott, he seems a really nice bloke and I know he's very knowledgable but not hugely engaging. Lets face it, this stuff is pretty dramatic and needs that sense of wonderment imparted to the masses. I like Pete Lawrence on sky at night too, he comes across as very engaging too.

[LukeSkywatcher]

Fisix aint my cup of tea. I switched over the channel after 20 mins.

*i'm aware i spelt physics incorrectly above*

[rory]

quote:::I never watch the Sky at Night these days as it pains me to see SPM in such poor health, hanging on to the programme and good luck to him but the whole programme needs a makeover again and new presenters, not Chris Lintott either. I find his style boring.">

i agree with that comment to a degree about the skyat night. although i dont mind s.p.m being in it.

i think it would be better if he had guest apperances now and then instead.

but definatly the show needs a better time slot to encourage youngsters into this hobby and revamp it a little. the beeb are normal quite good at this kind of thing,so it would be nice to give it a kick.

do a dr.who on it as it were.

[Reggie]

SPM is a permafeature of SaN, a guest slot just wouldn't be right. They reshow SaN on BBC4 though don't they? An early showing and a later showing. There should be more shows though, more than 1 a month, there is so much more to astronomy than they can ever cover. I'd much rather see more SaN than any more of those terrible 'bang goes the theory' programs.

[Anweniel]

I too would like to see more astronomy related programs, but beggars cant be choosers I guess :/

[astro mick]

Thanks Ixalon,for trying to explain this,but i,m still puzzled by the fact that by exiting an electron here,it effects electrons deep down inside a star billions of light years away.

Do electrons obey the speed of light,and if so this cant be instantanious.How do these electrons interact between vast distancies,yet still obey the laws of Pyhsics.

I must be totally on the wrong track with this,but my poor brain cant see round it.

In fact exiting electrons must be happening all the time,so it must be in a chaotic state permantly.

Oh dear,wish i had,nt watched now!!!!!!!!

Mick.

[661-pete]

The Pauli Exclusion Principle says no identical electrons can be precisely the same energy level.

Pauli's principal seems to actually state "two electrons, and more generally two fermions, cannot have the same quantum state (position, momentum, mass, spin)".

Your version seems to be more accurate than Cox's quote.

Of course two different electrons, in widely separated atoms, can have the same energy levels. Bear in mind that an energy level is never precisely defined: Heisenberg's uncertainty principle sees to that, in its representation:

ΔE.Δt > ħ/2

Even if you could observe an electron for the entire age of the universe you could never be precise about its energy.

So, subject to error, two or more electrons could indeed have the 'same energy level'. If it weren't for this most of our chemistry, electronics, indeed the whole basis for materials, wouldn't work (as Cox pointed out).

However: a quantum state, represented by a Schrodinger wave function, can be precise and have value across the whole Universe. It's the position, momentum and energy of the electron within that state that is indeterminate.

Sorry: a bit of hazy recall of undergrad. Quantum Mechanics popping out here! Correct me, anyone with better understanding!

[Pug]

Just watched it on iplayer. Really enjoyed it, despite the explanations in this thread I still can't get my head round the electrons thing! I like BC and the fact he made references to the mountain top and helicopter shots!

[LukeSkywatcher]

I like BC and the fact he made references to the mountain top and helicopter shots!

Haha yeah that was funny. Makes me wonder if he doesnt lurk in here. Its been said a few dozen times about those shots.

[Nova]

He may actively post in here for all we know.

Also liked the mention about the helicopter and mountain shots. And the "wistfull poitning into the sky" lol

[Duns]

I watched it on iPlayer last night - overall I think he did a good job and I'm sure it will have motivated some people to take more of an interest in Physics.

[Alan_B]

Personally I think BC does a good job of presenting and whenever I've watched his programmes I find he has a natural approach and seems tp pitch the content for a wide audience.

As to the use of helicopters and "arty" shots - I must admit it if was my job to host these shows I'd be off to the far corners of the planet as well if I could get away with it.

All in all he does a fine job - but maybe I'm biased due to my location

[JamesF]

I enjoyed it and learnt a few things even though I was already aware of a fair chunk of it. I think the editing was clumsy though. I'd like to see a "full length" version as there were places where the explanations were disjointed and I'm sure that wasn't what happened on the day.

One of the problems programmes such as this one have is trying to reduce things that are really beyond the average person's comprehension to something they can get a grasp of. I think they did a pretty good job. And I'm not intending to belittle people's intelligence here. Tonight for example I watched "Destination Titan", which I've had sitting around for ages. The fact that Saturn is a billion kilometres (or even a fair bit more) was repeatedly mentioned, and it's just something I cannot get my head around. In fact, that's one of the amazing things about seeing it, and its rings and moons through a telescope ("I can see all this, and it's further away than I can even imagine?"). When Cassini arrived at Saturn they were talking about it travelling at 30km/s. It wasn't until I thought "Hang on, that's here to Taunton and back before I could even get out of this chair" that it really meant something. So many aspects of astronomy, cosmology and quantum physics are so far removed from "human scale" that they really need to be demonstrated in more "real world" terms for most people to have a chance of understanding them. Some may object to it as "dumbing down", but if it gets more people to the point of thinking "Wow! That's astonishing" rather than "Uh. Don't understand. Not interested.", I for one will not complain.

James