You know the drill. You post physics questions, and I may answer them (If they aren't too fucking retarded). I'm gonna go grab a sandwich, I'll be back in 20min. Hope to have some good questions by then.

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Physics Guy Tue Dec 28 17:51:55 2010 No.2264445 [Reply] [Original]

You know the drill. You post physics questions, and I may answer them (If they aren't too fucking retarded).

I'm gonna go grab a sandwich, I'll be back in 20min. Hope to have some good questions by then.

>>	Anonymous Tue Dec 28 17:52:55 2010 No.2264446 Fucking magnets, how do they work?

>>	Anonymous Tue Dec 28 17:52:55 2010 No.2264448 Fucking magnets, how do they work?

>>	Anonymous Tue Dec 28 17:53:55 2010 No.2264449 >>2264446 /thread

>>	Samefag !SHjzCSZsqE Tue Dec 28 17:53:55 2010 No.2264451 Magnet fucking, how work they do?

>>	Anonymous Tue Dec 28 17:54:55 2010 No.2264457 Working magnets, how do they fuck?

>>	Anonymous Tue Dec 28 17:55:55 2010 No.2264461 Working fuck, how do they magnets?

>>	Anonymous Tue Dec 28 17:55:55 2010 No.2264463 working fucks , how to they magnets?

>>	Anonymous Tue Dec 28 17:56:55 2010 No.2264465 Magnets work, how do they fucking?

>>	Anonymous Tue Dec 28 17:57:55 2010 No.2264467 Magnets work, how fucking they do ?

>>	Anonymous Tue Dec 28 17:58:55 2010 No.2264469 How many permutations are there of 6 words?

>>	Anonymous Tue Dec 28 17:59:55 2010 No.2264474 Magnets magnets, how do they magnets?

>>	Anonymous Tue Dec 28 17:59:55 2010 No.2264475 >>2264469 this faggot, how does he work?

>>	Anonymous Tue Dec 28 18:00:55 2010 No.2264482 >>2264446 >>2264448 >>2264451 >>2264457 >>2264461 >>2264463 >>2264465 >>2264467 >>2264474 >>2264475 MIracles

>>	Anonymous Tue Dec 28 18:01:55 2010 No.2264484 >>2264469 720 65432*1

>>	Anonymous Tue Dec 28 18:02:55 2010 No.2264487 Magnets magnets, magnets magnets magnets magnets?

>>	Anonymous Tue Dec 28 18:02:55 2010 No.2264491 >>2264482 miracles, how do they work?

>>	Anonymous Tue Dec 28 18:03:55 2010 No.2264494 >>2264482 Fucking miracles, how do they work?

>>	Anonymous Tue Dec 28 18:04:55 2010 No.2264503 What do all of these symbols represent on this diagram? http://e-basteln.de/stm.pdf

>>	Anonymous Tue Dec 28 18:07:55 2010 No.2264507 Fucking miracles, how do they magnets?

>>	Anonymous Tue Dec 28 18:14:55 2010 No.2264526 miracles, how work they fuck do

>>	Anonymous Tue Dec 28 18:16:55 2010 No.2264533 >>2264494 Jesus

>>	Anonymous Tue Dec 28 18:21:55 2010 No.2264543 >>2264533 fucking Jesus, how they work?

>>	Anonymous Tue Dec 28 18:27:55 2010 No.2264558 It's all just a big gauss.

Josef !!nUf2NflSAyw Tue Dec 28 18:27:55 2010 No.2264559

Good to see your "ask me" threads again, I've been missing them. (... but I've got no open questions, eh, can't remember any. You should have posted a few weeks ago and we could've talked about CP violation in Kaon systems all night long, man that was an ugly topic for a seminar talk)

Oh, and you remind me of asking about the CERN trip. Some day I'll see the LHC. And probably you as well. Don't worry, you can censor your face with a "physics guy" label. ;)

>>	Anonymous Tue Dec 28 18:29:55 2010 No.2264562 What is the physics behind multi verse theory? What other ideas are behind this theory other than the hydrogen spin flip?

>>	Anonymous Tue Dec 28 18:31:55 2010 No.2264566 >>2264543 And I don't wanna talk to a priest Y'all motherfuckers lying, and getting me pissed Child rapists, and vicious Father Fifteen thousand faggots together

Physics Guy Tue Dec 28 18:36:55 2010 No.2264582
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>>2264503
There are alot of different componets here.

I see fullbridge recifiers, diodes, capacitors, resistors, transformers (voltage), and various IC logic chips, just at a glance. Any one in particular you are curious about?

Physics Guy Tue Dec 28 18:39:55 2010 No.2264593
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>>2264559
Actually,

If you go to CERN, I will be willing to meet face to face. It isn't a big deal to me. Serioulsy, just let me know in advance, and we can grab a coffee or something. I could probably even give you a behind the scenes tour (given things aren't too busy).

>>	Physics Guy Tue Dec 28 18:45:55 2010 No.2264605 File: 1.64 MB, 1467x2123, 1267915645621.jpg [View same] [iqdb] [saucenao] [google] >>2264562 You mean the MWI (Many worlds Interpertation) of QM (Quantum Mechanics)?

>>	Josef !!nUf2NflSAyw Tue Dec 28 18:45:55 2010 No.2264606 >>2264593 Sure! Mind mailing me so I can reach you outside 4chan? (Oskar can vouch for me I don't spam people) ;)

>>	Anonymous Tue Dec 28 18:45:55 2010 No.2264607 >>2264593 Someone of actual importance on 4chan. My mind has been blown.

>>	Anonymous Tue Dec 28 18:46:55 2010 No.2264610 Hi, can you please tell me why do we need 11 dim to confirme String theory ? Excuse my english, I'm frenchie

>>	Anonymous Tue Dec 28 18:48:55 2010 No.2264616 MAGNETS! I'M GONNA LIVE FOREVER! I'M GONNA LEARN HOW TO FLY (FLY)!

>>	Anonymous Tue Dec 28 18:48:55 2010 No.2264619 >>2264605 Yes, I do believe that is what I am referring to.

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Tue Dec 28 18:49:55 2010 No.2264620 >>2264593 I'd love to go to CERN, but I probably never will. Not even my dad goes to CERN, and he works on accelerators around the world. I'm not actually sure why he doesn't go to CERN...

Anonymous Tue Dec 28 18:50:55 2010 No.2264624
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>>2264445
Suppose you had a rigid object with two marked points on it. Physical changes propagate at the speed of light, and suppose the object is large enough that even proportionally small changes are detectable by the observer.

If a force acts on the 100% rigid object, will the observed distance between the two points decrease while the change propagates at lightspeed across its structure?

Anonymous Tue Dec 28 18:51:55 2010 No.2264628

Hey. A couple stormfront faggots took over /new/ last night. They accused Einstein of being a fraud and largely plagiarizing Max Planck and other "Aryan" scientists.

Being rather unfamiliar with the history of physics, I was unable to refute that claim.

Tell me, is there any merit to their assertion?

>>	Anonymous Tue Dec 28 18:55:55 2010 No.2264636 >>2264624 firstly, the changes propagate at the speed of sound through that particular medium secondly, you asked this yesterday and the answer is the same

Physics Guy Tue Dec 28 18:58:55 2010 No.2264644
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>>2264610
It is fine, I am surrounded by french speaking people like 30% of the time. CERN is on the Franco-Swiss border. While most scientist speak English, the staff, as well as all the shit around (closet city is Gevena) is pretty much all frenchfags....lol.

>why do we need 11 dim to confirme String theory ?

Do you mean, why does string theory have 11 dimensions? (Actually can have 10 dimensions, as the minimum)

>>	Anonymous Tue Dec 28 19:00:55 2010 No.2264645 >>2264620 The people who run CERN don't like having Americans around. Unless they are investors or minor technicians.

Physics kiddo Tue Dec 28 19:02:55 2010 No.2264652

I'll answer the symbols question since nobody wants to.
>>2264503
A full black triangle with a black bar in front is a diode. a square of these is a bridge rectifier. It turns alternative current into direct current. look it up. Diodes with arrows are LEDs.
A bunch of circles (look like curly hairs) means an inductor. On the left, next to T1 and T2, two curly + two bars means a transformer, it's made out of two inductors wound around a core.
empty rectangle + black bar + plus sign = electrolytic capacitor. two bars = capacitor.
empty rectangle = resistor, I'm not sure what it means when it's barred.
The thing at the far right is a connector.
The triangles are either ICs or transistors. Look up the piece numbers (here LM317) for more info.
Now, I'm not sure what the SI things are, I'd wager on fuses. Look around the documentation for the schematic.

Have fun !

>>	Anonymous Tue Dec 28 19:04:55 2010 No.2264655 Why does matter annihilate with antimatter?

Physics Guy Tue Dec 28 19:04:55 2010 No.2264656
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>>2264606
Don't know who Oskar is?

Anyway, you enjoy a good math puzzle, correct?

How can we arrange it, as so you could contact me (if you do come around CERN), but no one else can contact me (don't want to be bothered by /b/ tards)?

It is a classic Computer science type problem.
So, any ideas?

Anonymous Tue Dec 28 19:04:55 2010 No.2264658

Here is a question that was on my physics exam.
You have a smooth wedge of mass M inclined at angle A to the horizontal sitting on a smooth surface.
You have a particle of mass m on the wedge. The particle is allowed to slide down.
What is the resulting acceleration of the wedge?

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Tue Dec 28 19:05:55 2010 No.2264660 >>2264656 josef has an e-mail, just email him there.

>>	Anonymous Tue Dec 28 19:08:55 2010 No.2264668 >>2264656 Not the poster that your looking for, but you could always but it into a matrix. /b/ can't count to 5, so I'm pretty sure that hiding your information in that manor will work.

Josef !!nUf2NflSAyw Tue Dec 28 19:09:55 2010 No.2264671

>>2264656
My eMail is valid and goes to ... well, an address that is crappy enough to be posted on 4chan.
Oh, and Oskar is some other guy who posted here a few months ago. I haven't seem him around lately, but he's in my ICQ contact list, I've got his thesis etc.

Anonymous Tue Dec 28 19:17:55 2010 No.2264693

OP: relativity says that time is a dimension, but according to quantum mechanics it isn't.

WAIT! I just had a better question, is their any interperatation of quantum mechanics in which time is a dimension like in relativity? Because that interperation is probably correct.

>>	Anonymous Tue Dec 28 19:21:55 2010 No.2264704 >>2264636 No, I didn't. Maybe someone else did.

Physics Guy Tue Dec 28 19:26:55 2010 No.2264720
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>>2264605
There are hundreds of Interpretations of QM and most are equally valid. There is no more evidence for the MWI then for the CI (Copenhagen Interpretation).

In QM we have a system that works. It works remarkebly well, better then anything ever, but it is full of some abstarct unobservable ideas.

You have all these "abstract unobservable ideas", somehow leading to leading "physical observables". When people develop an interpretation of QM they are seeking to figure out the nature off all the werid unobservable shit.

But you can't measure experimentally any of it, hence you can't know if your are right or wrong. Hence you get unfalisble theories, which are not science. All you get a fancy ways to explain subtles in the math, you don't actually get physics.

Hence, Interpretations of QM are usually not covered too much in QM. In fact Philosophers of Physics often think about that shit way more then Actual Physicists.

>>	Anonymous Tue Dec 28 19:26:55 2010 No.2264721 Why haven't you guys found the higgs boson yet?

>>	Anonymous Tue Dec 28 19:31:55 2010 No.2264740 >>2264720 >There is no more evidence for the MWI then for the CI (Copenhagen Interpretation). what about time-dialation? is expirimentally observed time-dialtion compatible with the copenhagen interpertation?

>>	Anonymous Tue Dec 28 19:33:55 2010 No.2264747 >>2264720 http://www.foxnews.com/scitech/2010/04/05/freaky-physics-proves-parallel-universes/ Is this a good explanation as to how the physical observations of QM can lead to the abstract theories of QM?

Physics Guy Tue Dec 28 19:33:55 2010 No.2264749
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>>2264693
Good question.......

The QM you are refering to is a very very dumbed down version of the real type of Quantum Mechanics physicst actually use.

Physicist actually use a type of Quantum called QFT (quantum field theory). In QFT we do incoperate Special relativity, hence time is a dimension. QFT is the standard which physicist use.

>>	Anonymous Tue Dec 28 19:34:55 2010 No.2264756 >>2264628 Einstein was a fraud.

>>	Anonymous Tue Dec 28 19:43:55 2010 No.2264777 how do you make physical objects change dimension?

Physics Guy Tue Dec 28 19:43:55 2010 No.2264779
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>>2264740
Time dilation is actually already incorperated into advanced physics. It is a given, it is already in QTF, and the Standard Model. Time Dilation has no relavence on the Interpretations of modern QM. Every modern theory has time dilation already.

>>2264747

You may have misunderstood what I ment, QM interpretations are actually very very mathematically sound theories. They are usually very clever, and very good hypothesis, made by very very smart scientists/mathematicians. However, they still can not be tested yet.

MWI and CI are good theories, they actually make alot of fucking sense and have valid points. However, neither is testable yet.

FAUX news is just an example of bad journalism, it doesn't even matter what they report on anymore, it is just fucking sad.
Not even looking at a FAUX news article.

>>	Physics Guy Tue Dec 28 19:45:55 2010 No.2264785 File: 84 KB, 350x445, Einstein-Laughing-1.jpg [View same] [iqdb] [saucenao] [google] >>2264671 Ok, if you want to give me your email, I will email you.

>>	yellow Tue Dec 28 19:45:55 2010 No.2264786 File: 7 KB, 910x457, yellow.jpg [View same] [iqdb] [saucenao] [google] why does the second law of thermodynamics not apply to amino acids in the formation of single celled new life on distant stars?

>>	Anonymous Tue Dec 28 19:47:55 2010 No.2264793 What is "time"? I guarantee your answer will be incorrect.

Anonymous Tue Dec 28 19:49:55 2010 No.2264794

>>2264779
Apologies for the faulty source. It was just the one I had bookmarked. The experiment out of University of California Santa Barbra was actually well documented. I have a second source if it helps. I'm intrigued to hear your opinion on their experiment.
http://www.google.com/hostednews/afp/article/ALeqM5jU3CIMYJyDHMFvHg1qYUQ0ycPAXw?docId=CNG.fe1d058988
6b23ad62bffe61357001df.b01

Physics Guy Tue Dec 28 19:52:55 2010 No.2264797
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>>2264786
>second law of thermodynamics

You have a common misunderstanding on the validity of thermodyanmics laws. I am not sure if they actually apply to your system or not, but FYI thermodynamics doesn't apply to alot of shit.

Regular Thermo rules only apply to very very very specific types of statistical systems. There are tons and tons of shit that you wouldn't apply thermo to.

Thermo isn't some fundamental rule applicible to all of physics, it is a very specific set of rules, for very specific types of systems.

>>	Anonymous Tue Dec 28 19:54:55 2010 No.2264800 >>2264777 not trolling, plz tell us how dimensions work. thanks.

Josef !!nUf2NflSAyw Tue Dec 28 19:54:55 2010 No.2264802

>>2264797 Ok, if you want to give me your email, I will email you.
That's what I've been trying to tell you all the time, my eMail is in my eMail field. Hover over my name and tadaa, rhizÃ¶me.dÃ¶t.josef.at.googlemÃ¤il.dot.cÃ¶m
I'll let you decypher the code ;)

>>	yellow Tue Dec 28 19:56:55 2010 No.2264809 File: 7 KB, 927x465, yellow1.jpg [View same] [iqdb] [saucenao] [google] >>2264797 examples please I want to know more

>>	Anonymous Tue Dec 28 20:06:55 2010 No.2264834 >>2264582 I was actually wondering what the purpose is of putting the 4 diodes in a square shape as he does on page two four times.

Anonymous Tue Dec 28 20:07:55 2010 No.2264836

>>2264809

All the rules of thermodynamics only apply to isolated systems, IE things that do not interact with the outside world at all. Treating an organism or even the planet as isolated systems is retarded on a huge scale because we have a massive fusion reactor overhead giving us concentrated energy we can use to do work.

>>	Anonymous Tue Dec 28 20:09:55 2010 No.2264842 question OP, do you believe there exists a final theorie, and do you think the actual world is exactly describable in mathematical terms?

>>	Anonymous Tue Dec 28 20:10:55 2010 No.2264845 File: 29 KB, 594x350, intrade.png [View same] [iqdb] [saucenao] [google] What year do you think we will find the Higgs Boson particle? I promise I will bet $200 on the year you guess. Pic related.

Physics Guy Tue Dec 28 20:10:55 2010 No.2264847
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>>2264794
Yeah, I actually have heard of this before. This would actually seem to disprove the MWI more then back it up. If I am able to see the particle existsing in two completely different states, then these states are both in our universe. Right?

Also, these types of experiments have been done before already. The ability to see a particle exist in multiple states, has been around for a while. The only thing novel about UCSB's experiment is that it can be done with a naked eye, instead of needing magnification.

Don't get me wrong. It is a good experiment, but it really doesn't have any deep implication on Interpretations of QM. It is just one of those stories that the media twisted around, giving it way more importance then the actualy physics community did.

Anonymous Tue Dec 28 20:13:55 2010 No.2264854

>>2264845
no good idea to bet imho. it's not a given that there is a higgs particle. In fact, I'd guess there are many people who'd like it to not exist. Particle Physicists of course wan't it to exist, and it would be good if it's there from a political point of view, but ...

>>	Anonymous Tue Dec 28 20:16:55 2010 No.2264858 >>2264847 Are you actually at CERN? Which accelerator? My University and Supervisor have a team working at the LHC's CMS. I'm planning on visiting it in June.

Josef !!nUf2NflSAyw Tue Dec 28 20:17:55 2010 No.2264860

>>2264854
Some particle physicists I've spoken to said we'd be wondering what particle physicists measured for the last 30 years if the Higgs doesn't exist.
Some profs on statistical physics (that is ... one.) told me they'd be happy if it was falsified because then we'd have to look for new interesting theories. (He isn't exactly happy with the beauty of the standard model)

>>	Anonymous Tue Dec 28 20:18:55 2010 No.2264862 I'm tempted to go into Astrospace engineering, but i'm fascinated with theoretical physics. Is there a good way to combine the two in your opinion?

Physics Guy Tue Dec 28 20:19:55 2010 No.2264865
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>>2264836
Sounds about right

>>2264809
In addition the elementary rules of thermodyanics only apply to systems where you can define a temperature. (There are tons of physics systems with no such notion).

>>2264834
The 4 diodes are what we call a bridge rectifier. It allows us to convert and incoming AC signal to DC singal. (Adding capacitors and Resistors, will smooth out the DC)

This article explains it very well.

http://en.wikipedia.org/wiki/Diode_bridge

>>	Anonymous Tue Dec 28 20:20:55 2010 No.2264867 What is your age? What is your yearly wage? What do you have a degree in? How many years have you worked? How do I become smart like Josef?

>>	Anonymous Tue Dec 28 20:20:55 2010 No.2264868 File: 16 KB, 235x267, JGJ.jpg [View same] [iqdb] [saucenao] [google] >>2264860 >the beauty of the standard model

>>	Josef !!nUf2NflSAyw Tue Dec 28 20:21:55 2010 No.2264871 >>2264868 That's what I've been referring to.

Physics Guy Tue Dec 28 20:25:55 2010 No.2264876
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>>2264845
I personally don't think it will be found. Most physicst I know don't think it will be found.

>>2264854
>particle physicsts what it to exist

No, not really. I would say it is about 50/50.

>>2264860
The standard model is mathematicall beautiful, however I agree with your stats proffs. I hope the Higgs doesn't exist, simply cause I want a better model!

Anonymous Tue Dec 28 20:27:55 2010 No.2264886
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what would you say is more essential to quantum mechanics (including QFT ect.)
the superposition principle or the definition of observables?
or something else?
and what is so special about the superposition principle and about the definition of observables

>>	Anonymous Tue Dec 28 20:30:55 2010 No.2264889 >>2264876 what is beautiful about it? The cartan geometry part about it (Yang Mills ect.) is really beautiful but everything beyond its quantisation is quite yikes. define what you mean by "better model"

Josef !!nUf2NflSAyw Tue Dec 28 20:30:55 2010 No.2264890

>>2264876 The standard model is mathematicall beautiful
From what I've learned about it (pretty basic stuff though) it's ugly as hell. I mean the pictures are nice, but ... I mean just look at the Lagrangian, and that's the nice and condensed form. Perturbation theory all day long, index chaos, aarrrrr <span class="math">\bar u\gamma^\mu ug_{\mu\nu}blaaaaaaaaaaaa[/spoiler]
Well maybe that's because I've learned it from people calculating tens of thousands of graphs and not mathematical physicists.

>>	Anonymous Tue Dec 28 20:30:55 2010 No.2264892 Why does anti-matter and regular matter annihilate? I understand the concept of (as an example) charges negating and equaling zero, but how does something with mass do this? How are the two forms of mass differentiated?

Physics Guy Tue Dec 28 20:36:55 2010 No.2264901
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>>2264842
>do you believe there exists a final theorie

Nope

>actual world is exactly describable in mathematical terms

I, like most physicist, believe in an infinite amount of different ranges of validity. Even the standard model is known to only work within a certain energy range. There are an infinite amount of mathematical theories that can explain the physics occuing in a given range of validity.

However, there will always be another range of validity. Hence we will never be actually be "done" with physics, and we will always be scrambing to model it with some fancy "mathematics".

>>	Anonymous Tue Dec 28 20:36:55 2010 No.2264902 >>2264890 Especially the way you add in particle masses is ugly as fuck. The Higgs mechanism is slightly contrived, but not so much in it self, but when you want to add the different particlemasses, each species requires a coupling constant of its own.

Anonymous Tue Dec 28 20:39:55 2010 No.2264909

Why are Fermions and Bosons put on the same chart like they're the same thing?
Aren't fermions energy/waves/particles and Bosons are forces?
What is the difference between the 12 Fermions?
What is the difference between a wave and a particle?
What is the structure of an atom down to the Fermions?
Are all of the Fermions energy?

Physics Guy Tue Dec 28 20:47:55 2010 No.2264925
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>>2264890
>>2264889
Well, beauty really is in the eye of the beholder. You really can't quantify it to well.

I really like all the hidden sysmetery shit in the standard model, as well as the group theory, I always really enjoyed that type of math.

I do hate a ton of shit about it though. Supersymmetry is shit, as well as the electroweak unification. I mean wtf? You start with two properties, then you change basis, and you get two different properties? AND THAT IS CALLED A UNIFICATION? LMAO

I mean I get the justification, and the equivalence at certain energy ranges, but still, it always has seemed pretty weak to me (no pun intended).

And don't even get me started on the masses!!!!

>>	Josef !!nUf2NflSAyw Tue Dec 28 20:48:55 2010 No.2264926 >>2264909 I can't help chuckling, thinking about PhysicsGuy typing a whole book into the tiny 4chan window now ;)

Josef !!nUf2NflSAyw Tue Dec 28 20:50:55 2010 No.2264929

>>2264925
The Yang-Mills chapter is still ahead of me, also principal bundles are mocking me. <span class="math">\mathrm{Tr}F\wedge*F[/spoiler] etc ... promising at least. It's a shame nobody seems to be interested in that because it doesn't simplify Feynmans.

>>	Josef !!nUf2NflSAyw Tue Dec 28 20:57:55 2010 No.2264945 >>2264929 Eh wait, I just mixed up two things there. Badly. No need to point it out. Please don't. Embarassing. Noes.

>>	Anonymous Tue Dec 28 20:58:55 2010 No.2264948 Hey OP, I got a real question here So water only evaporates when it reaches 100 degrees C. But why does it dry itself at normal temperature?

>>	Anonymous Tue Dec 28 20:59:55 2010 No.2264952 >>2264945 You can delete posts, you know?

Physics Guy Tue Dec 28 21:00:55 2010 No.2264953
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>>2264886
I would say the definition of observables is more important then superposition. Only becuase you actually use superposition in regular mechanics as well.

By the time you take QM you should already be familar with superposition (it isn't just a QM idea). The whole idea on non-commuting oberavbles, and actually using linear algebra in physics (not just matrx algebra) is first introduced in QM.

Superposition in QM tells you that things can actually exist in mutiple states at once. Observables tells you that the properties you "normally" attribute to somthing, may not actually exist in nature. Ie, position and mometum actually don't exist in nature. They only come into being once an object is interacted with properly.

>>	Anonymous Tue Dec 28 21:03:55 2010 No.2264962 >>2264948 Not OP, but look up vapor pressure.

Physics Guy Tue Dec 28 21:07:55 2010 No.2264968
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>>2264858
Yes, I work on the CMS as well. I guess I will see you in June. You will be what we call a "summer student". I await the opportunity to haze you ....lol.

My only advise is to bring own power outlet converter. The ones they sell at the little store on site are expensive as fuck! And good luck trying to find cheap stuff in Gevena! Rich Arabs everywhere!

>>	Physics Guy Tue Dec 28 21:09:55 2010 No.2264971 File: 75 KB, 501x599, 501px-Medeleeff_by_repin.jpg [View same] [iqdb] [saucenao] [google] >>2264968 Not that I have anything against Arabs. It is just not what you would think of, when you think of Switzerland.

Physics Guy Tue Dec 28 21:11:55 2010 No.2264979
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>>2264892
The two forms of mass are not differentiated. There is only one kind of mass. Both a particle and it's antiparticle have the same mass.
Mass can be convereted into energy, and visa versa.

>>	Anonymous Tue Dec 28 21:16:55 2010 No.2264991 >>2264979 not the poster, but why do they do it? why dont the nuclear forces simply stop them from colliding/annihilating? do two netrons annihilate?

>>	Anonymous Tue Dec 28 21:21:55 2010 No.2265012 File: 65 KB, 479x600, hatersgonnahatealbert.jpg [View same] [iqdb] [saucenao] [google] >>2264953

Anonymous Tue Dec 28 21:22:55 2010 No.2265015

>>2264948
same mechanism. but at 100Â´ the intermolecular forces can no longer hold the molecules together and they fly away (more or less at the same time)
in a glass of water there is a statistical distribution of molecule velocities(which average out to the temperature more or less) and a fraction has enough speed to "go free" from the water and hence it evaporates slowly

Physics Guy Tue Dec 28 21:32:55 2010 No.2265040
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>>2264991
>why dont the nuclear forces simply stop them from colliding/annihilating?

First of all nuclear forces only apply to shit like atoms and molecules, it makes no sense to speak of nuclear forces in particle physics. And when speaking of annilation you usually are actually speaking of particle physics.

There are 4 forces in particle physics, and they actually work by particle exchange. Ie, a partcile will emit a "force carrier", which in turn will be absorbed by another particle. These are the only type of "force interactions" that actually occur in nature.

The prime example of annilation is the electron and the positron. They both annilate each other, and create two photons.

http://en.wikipedia.org/wiki/Electron%E2%80%93positron_annihilation

In this reaction, charge is conserved, as well as energy/mass/momentum. As all the mass, energy, and mometum of the orginal particles, are converted to the energy/momentum of the two photons.

>>	Physics Guy Tue Dec 28 21:33:55 2010 No.2265045 File: 99 KB, 600x738, david-hilbert.jpg [View same] [iqdb] [saucenao] [google] >>2265012 Thanks for the pic

>>	Anonymous Tue Dec 28 21:38:55 2010 No.2265063 File: 64 KB, 479x600, mark_twain_tiny_pistol.jpg [View same] [iqdb] [saucenao] [google] >>2265045

Physics Guy Tue Dec 28 21:43:55 2010 No.2265080
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>>2264991
>do neutrons collide

They could collide, but they would not annihilate.
The Neutron is made (simply) up of 3 quarks (held together by gluons). It is made up of u, d, d quarks. If I hade two Neutrons I would have 6 quarks u, u, d, d, d, d. None of these are the antipartciles of each other, so they will not annihilate.

http://en.wikipedia.org/wiki/Neutron

In order to annihilate a neutron, I need an Anti-Neutron. It is made of anti-u, anti-d and anti-d.

http://en.wikipedia.org/wiki/Antineutron

>>	Anonymous Tue Dec 28 21:44:55 2010 No.2265081 >>2265040 was thinking of strong/weak force i guess, pardon my english. i understand that energy and charge is conserved. but do 2 neutrons annihilate?

>>	Physics Guy Tue Dec 28 21:44:55 2010 No.2265083 File: 43 KB, 485x560, schrodinger.jpg [View same] [iqdb] [saucenao] [google] >>2265063 Nothing wrong with Mark Twain Thanks again

>>	Physics Guy Tue Dec 28 21:46:55 2010 No.2265090 File: 12 KB, 267x326, Noether_Emmy_8.jpg [View same] [iqdb] [saucenao] [google] >>2265081 No they don't, as a Neutron isn't actually its own anti-particle, and Anti-Neutron is. see >>2265080

Anonymous Tue Dec 28 21:48:55 2010 No.2265101

>>2265090
>as a Neutron isn't actually its own anti-particle
Speaking of which, isn't the Photon actually its own anti-particle?
Do photons annihilate each other? And would a new photon with the combined energy of both previous photons be created in the process?
Does this make sense or does it actually not happen?

>>	Anonymous Tue Dec 28 21:50:55 2010 No.2265108 File: 21 KB, 819x460, Bad drawing.png [View same] [iqdb] [saucenao] [google] Will this levitate?

>>	Anonymous Tue Dec 28 21:51:55 2010 No.2265112 I wish I was a physicist. Sadly I will never be so awesome. IÂ´ll either end in a boring office or IÂ´ll kill myself within the next for months.

Physics Guy Tue Dec 28 21:59:55 2010 No.2265140
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>>2265101
Good question

>Do photons annihilate each other?

Yes they can

>And would a new photon with the combined energy of both previous photons be created in the process?

All sorts of crazy shit could happen, including new photons, or simply the reverse of electron-positron annihilation. Hence you could get two photons to annihilate and become an electron and a positron.

>Does this actually occur

Happens all the time

>>	(m)ass Anonymous Tue Dec 28 21:59:55 2010 No.2265141 Is the reason for the increase in mass of an accelerating object understood? If so, could you briefly explain?

>>	Anonymous Tue Dec 28 22:02:55 2010 No.2265146 >>2265140 Interesting, thanks.

>>	Anonymous Tue Dec 28 22:04:55 2010 No.2265148 how is momentum anything more than an entirely contrived unit, and why the fuck is the product of mass and velocity conserved in a collision? yes, a little more elementary, but the only basic concept i can't seem to conceptualize

>>	Anonymous Tue Dec 28 22:04:55 2010 No.2265149 >>2265141 In addition to that: what do you think of the concept of "relativistic mass"? Outdated? And, how did you learn it?

Physics Guy Tue Dec 28 22:05:55 2010 No.2265150
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>>2265101
Also, a single photon could just turn into an electron positron pair.

http://en.wikipedia.org/wiki/Pair_production

Likewise, the pair could then combine back to form a photon. And then the photon could go for awhile, then split again, then combine, then go, then split, combine....etc. This could go on indefinelty. It is called the "self interaction".

Physics Guy Tue Dec 28 22:14:55 2010 No.2265164
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>>2265141
>>2265149
Assuming you ment to say the velocity of mass, not acceleration?

The reason why you could define a "relativistic mass" that increases with velocity is very well understood. It is just how you used the math of special relativity, how you defined the varibles. However the concept of relativistic mass isn't really used too often in the modern particle physics community.

The whole concept was supposed to simplify shit, however it just lead to misunderstanding, and some people actually assuming that somthing in motion "created more matter". Einstein himself didn't like the idea of relativistic mass.

I have never had to use relativistic mass in physics.

>>	Anonymous Tue Dec 28 22:15:55 2010 No.2265166 how do i magnets?

Anonymous Tue Dec 28 22:18:55 2010 No.2265171

>>2265150
Actually, no, a photon can't just turn into a particle-antiparticle pair. It violates momentum conservation.

You need another particle to be involved in order to conserve momentum.

For the same reason, particle-antiparticle annihilation generates, at a minimum, TWO photons.

>>	Anonymous Tue Dec 28 22:20:55 2010 No.2265176 >>2265171 Unless he's referring to virtual particles and QED.

>>	Anonymous Tue Dec 28 22:26:55 2010 No.2265188 Please explain how mercury's orbit was explained by General relativity.

>>	Anonymous Tue Dec 28 22:29:55 2010 No.2265198 >>2265188 http://en.wikipedia.org/wiki/Tests_of_general_relativity#Perihelion_precession_of_Mercury

>>	Anonymous Tue Dec 28 22:36:55 2010 No.2265218 Is moving from Newtonian theory of gravity to General Relativity a bigger leap "physic"ly or philosophically?

>>	Anonymous Tue Dec 28 22:36:55 2010 No.2265219 File: 68 KB, 407x405, 1293086933497.jpg [View same] [iqdb] [saucenao] [google] How was electroweak theory formed?

Physics Guy Tue Dec 28 22:41:55 2010 No.2265230
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>>2265148
Mometum is not actually m*v, momentum is actually somthing more fundemental. It may simplify to m*v for very basic systems. In addition, momentum actually may not be conserved, it again depends on your system.

Basically, to derive the defintion of mometum and if conservation arises, you must start off from some more fundemental physics.

In Short:
You basically minimize the difference between the energy you "do have" and the energy you "can have", over all possible paths in space-time (least action principle). The assumtptions you make about the forms of energy you "can have", and the energy you "do have" are purely done from experiment. From these energy combinations you end up having certain mathematical "symmetries".

These symmetries will lead to conserved quantities in your least action principle, Nothers theorm. Hence, we end up have symmetries of nature, and a conserved quantity arising from each symmetery.

The symmetry known as "time homogenity", implies "conservation of energy".

The symmetry know as "gauge symmetery", implies "conservation of charge".

The symmetry known are "spatial translational invarience" implies "conservation of momentum".

Hence,
The manipulation of your Least action equation, will lead you to the approperate definition of "momentum" for your system. And if your system has "spatial translational invarience", then your system has conservation of that momentum. This symmetry basically means that I could shift my system anywhere (no rotation), and the same physics should happen.

Sorry, if it is a bit over your head, but you actually asked a kinda deep question.

>>	Anonymous Tue Dec 28 22:43:55 2010 No.2265241 File: 26 KB, 619x352, 127629679242bb2.jpg [View same] [iqdb] [saucenao] [google] >>2265230 WHOA

Physics Guy Tue Dec 28 22:50:55 2010 No.2265264
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>>2265171
>photon can't just turn into a particle-antiparticle pair. It violates momentum conservation.

It happens all the time, and it is well documented.

Look at the "Electron-positron pair production" @
http://en.wikipedia.org/wiki/Pair_production

Why would you think It violates anything?
U trollin?

>>	Anonymous Tue Dec 28 22:52:55 2010 No.2265272 >>2265264 Do you have any way of communication? Just curious. I only have one person in my life like you, it'd be pretty awesome to have another. But, obviously you don't have to

>>	Anonymous Tue Dec 28 22:55:55 2010 No.2265279 >>2265230 are these concepts conceptual concepts or mathematical concepts? ie do you need to know differential equations or something to understand the "least action principal"?

>>	Anonymous Tue Dec 28 23:01:55 2010 No.2265297 Does light have gravity? As in, can it attract things?

Physics Guy Tue Dec 28 23:02:55 2010 No.2265302
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>>2265219

It is all in the first paragraph or so.

http://en.wikipedia.org/wiki/Electroweak_theory

I would be happy to clarify anything for you, but you really should read the article first.

>>2265218

Well, that is a matter of opinion. I would say Phil, since non-eucliean geo already existed (just wasnt too main stream). Phil alwyas seems to make huge implication based on modern physics, often many of them pretty ridiculous. There are usually whole classes, devoted to the phil implications of relativity at Uni, I had to take one myself.

Study alittle about the implications phils derived from GR, and make an educated opinion of your own.

http://plato.stanford.edu/entries/genrel-early/

>>	Anonymous Tue Dec 28 23:04:55 2010 No.2265309 Glad to see this thread is still up, I have a question I hope someone can answer :3 Since humans cant see atoms etc. with just our eyes, are there things so large we can't see them?

Physics Guy Tue Dec 28 23:19:55 2010 No.2265347
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>>2265279
Actual math is needed to apply and produce results. Physics is need to interpret and modify your hypothesis accordingly, as well as make the connection to the physical universe.

Concepts such as "Least Action", "Symmetry" and "Conservation" (and the interplay between them), could perceivably be explained in a grad level "philosophy of physics" course (without the math or physics). The Concepts themselves (while mathematically consistent and physically verified) can be introduced without physics or math.

As in all forms of teaching, it is all about making the material relavent to the audience. However a good phil of physics teacher is often hard to find. If Interested, you should go to your local uni, find the teacher of "phil of physics", and ask for relavent books that introduce these subjects for the "unmathematically inclined".

Note: if so, you will never know it as well as the physicist or the mathematicans. But at least you will be familar with the basics.

>>	Anonymous Tue Dec 28 23:21:55 2010 No.2265350 Explain total internal reflection and the concept of a critical angle, for some reason no matter what I've read about it the intuition isn't coming, my books are too vague and I never get proper diagrams.

Physics Guy Tue Dec 28 23:23:55 2010 No.2265354
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>>2265297
Anything with Momentum produces what we call gravity. Light (Photons) always has to have momentum, so light always produces gravity.

So yes, light can attract shit gravitationally. It is usually a very very very very very very small effect though.

>>	Anonymous Tue Dec 28 23:24:55 2010 No.2265355 File: 18 KB, 300x201, 1275417294017.jpg [View same] [iqdb] [saucenao] [google] >>2265347 U R KING OF /SCI/

Anonymous Tue Dec 28 23:26:55 2010 No.2265358

>>2264865

Goes with the second part of this post

I have no idea if you'll be able to answer this, but because white dwarfs are electron degenerate (and neutron stars possibly, I can't quite remember if their outer shell is e- degenerate or not), and because temperature is dependent on actually being able to transfer KE between one object and another temperature loses its meaning correct?

But would the objects feel like absolute zero (assuming you could somehow magically touch them without being crushed by the gravitational effects) or would they still feel, well not hot because they can't transfer any of that KE, but like....something....eh hard to think about

Any ideas?

>>	Anonymous Tue Dec 28 23:29:55 2010 No.2265361 Fucking niggers, how do they work?

>>	Anonymous Tue Dec 28 23:42:55 2010 No.2265382 So when a particle and its opposite antiparticle come in contact, they annihilate. What if, for instance, an antiproton and a neutron, or a positron and a proton came into contact?

Anonymous Tue Dec 28 23:43:55 2010 No.2265385

I've seen the math behind blackbody radiation and ultravioled catastrophe...but there shouldn' t be a simple explanation of why does classical physics predicts infinite radiation? Does that prediction says that classical physics predicts that bodies sould lose all their enery instantly from thermal radiation?
I think some absurd predition should be evident from basic principles

>>	Anonymous Tue Dec 28 23:43:55 2010 No.2265387 >>2265358 Also this is sort of a philosophy of physics/actual physics question since I think I understand what is actually going on pretty well.

Physics Guy Tue Dec 28 23:45:55 2010 No.2265389
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>>2265358

>because temperature is dependent on actually being able to transfer KE

The basic definition of temperture is related to the statistical average of kinetic energy of a system.

Even if the objects in the system are not transfering kinetic energy to each other, you could define a temperture. Conversly, you could use a more fundemental defintion of temperture which is related to degrees of freedom. Your system probably has some degrees of freedom, that arise from things other then kinetic motion.
(So you can define temperture in a multitude of ways)

Assuming you stick with the basic KE related defintion, your idea is analagous to the temperture of free space. The Temperture is about 2.7 K (pretty fucjking cold). However, since there isn't too much shit is free space, the ability to transfer "heat or cold" to you, would be alot slower, then if you were in some liquid that was 2.7 Kelvin. Make sense?

Free space, and the Liquid both have the same temperture, however, their ability to transfer heat is different.

Physics Guy Tue Dec 28 23:51:55 2010 No.2265397
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>>2265358
>>2265389

For the boundary, you would probably actually use a defintion of temperature related to the degrees of freedom. Becuase it is exotic material, it will have some fucked up degrees of freedom. Likewise it is actually possible to get negative temps and imaginary temp, it gets really fucking complicated.

http://en.wikipedia.org/wiki/Negative_temperature

>>	Anonymous Tue Dec 28 23:52:55 2010 No.2265398 Why exactly do matter and anti-matter vaporize each other?

>>	Anonymous Wed Dec 29 00:01:55 2010 No.2265410 How does our not knowing the exact state of a particle tell us that it must be everything?

Physics Guy Wed Dec 29 00:02:55 2010 No.2265411
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>>2265382
Then different shit happens. That is pretty much what particle physics is.

You say, what happens when A and B come together. Usually a multitude of different things can happen, as long as they obey certain conservation laws.

There is a huge fucking list published every year, with all known particle interactions, and the rules that govern each.

The List is probably in the hundreds of thousdands if not more....

It is made by the "Particle Data Group"
http://pdg.lbl.gov/

And is free, just go to where it says order PDG products!

Anonymous Wed Dec 29 00:02:55 2010 No.2265413

>>2265389

But because of PEP aren't all of the available energy levels (Orbits, shells, whatever name you want to call them) filled up.

So essentially graph density on the Y-axis and KE, temp, some other analogous property on the X with the PEP limit as an asymptote (essentially) at the top. Density can only increase up to the PEP limit because fermions can't lay on top of each other in PEP.

So at this point you have a graph with all available energies "smushed" up against the PEP limit (a straight line that goes along the limit to infinity and falls off abruptly to 0 at the origin).

Doesn't this mean that there are no degrees of freedom (what I meant when I said KE transfer defines temp) in this system?

>>	Anonymous Wed Dec 29 00:04:55 2010 No.2265416 >>2265413 No extra energy slots means perfectly solid even if the particles constitue up a gas. Why we don't fall through the floor, etc. ; right?

Physics Guy Wed Dec 29 00:14:55 2010 No.2265430
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>>2265413
Ohh, ic. So, I just have a super dense structure obeying PEP. But why are you saying the electrons aren't moving? I know that the whole thing is pressureized as fuck, but surely, that doesn't physically restrict the electrons? They still have probablistic shell distributions, and still have an average Kinetic energy? Maybe I am not understanding your problem?

Physics Guy Wed Dec 29 00:19:55 2010 No.2265435
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>>2265416
>>2265413

PEP type energy levels do not physically set the position of an object, it only limits it. The object is still probablistic, it is still moving, it still has kinetic energy.

Anonymous Wed Dec 29 00:19:55 2010 No.2265436

I've seen the math behind blackbody radiation and ultravioled catastrophe...but there shouldn' t be a simple explanation of why does classical physics predicts infinite radiation? Does that prediction says that classical physics predicts that bodies sould lose all their enery instantly from thermal radiation?
I think some absurd predition should be evident from basic principles

>>	Anonymous Wed Dec 29 00:23:55 2010 No.2265441 I remember reading a very interesting topic some years ago in Science about teleportation. Can you post some basic formulas? P.S.: don't spam with nuclear sythesys/gravitaty or whateverthefuck I can find easily on internet

Anonymous Wed Dec 29 00:25:55 2010 No.2265444

>>2265430

Yeah I'm probably not explaining it 100% accurately and I don't have my astro textbook here beside me.

I think what my professor was claiming was that because it was obeying PEP completely it couldn't transfer any energy to me therefore since there are "no degrees of freedom" in the system between me and it (it being something like a white dwarf or just an extremely pressurized gas [same fucking thing]), and likewise I couldn't interact with it like putting my hand through it or anything like that.

For a floor example. Since the floor and I are at such a low temperature the "space" between the curve and y-axis (assuming we're in the first quadrant) is very small, and so the floor and the soles of my shoes (or feet) reach degeneracy much easier and I don't have to be under a lot of pressure to reach it.

Physics Guy Wed Dec 29 00:29:55 2010 No.2265450
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>>2265410
You have a common misconception that alot of people have. You think that our inability to measure shit, is in fact cause we have shitty measuring devices. You think that the heisenberg uncertainity principle comes from our sucky measuring techniques. LMAO.

The actualy measurment problem is much deeped then that. When we do formulate uncertainties, we assume we have perfect measuing devices. The measurement problem is an actual consequence of quantum behavior.

Quantum shit can be non-commutivitve, this leads to a natural uncertainity of nature. Superposition of states (which has been experimentally observed), leads to things existing at multiple places at once, or not existing at all, until observed. All this shit is experimentally verified, and we like to believe shit that is true.

>>	Anonymous Wed Dec 29 00:32:55 2010 No.2265453 >>2264655 Someone answer this.

Physics Guy Wed Dec 29 00:34:55 2010 No.2265456
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>>2265444
The electron structure of atoms obey the PEP completely, and they still manage to transfer energy. PEP is limitless, you can always pile up more electrons, just add another energy level. And PEP, just limits the electrons to funky orbitials, it doesn't actually "freeze" them from moving.

Anyway, I have no idea what your proffessor was trying to say. Sorry.

Anonymous Wed Dec 29 00:39:55 2010 No.2265463

>>2264445
So this relativity thing--everything is just kind of contingent on everything else and it goes on and on like this domino thing which is probably one reason we really don't know when things started because everything like leans on each other, so to speak.

What a pain not to be really be able to answer certain questions.

Anonymous Wed Dec 29 00:40:55 2010 No.2265465

>>2265456

Yeah. That's pretty much what I was getting at. The electrons themselves aren't "frozen" they still move; it's simply that if all the "orbitals" are filled up then I can't physical do any energy transfer with them. There's no where for the energy to go.

Physics Guy Wed Dec 29 00:48:55 2010 No.2265474
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>>2264655
The answer to "why" does "x and y" do "z" in particle physics (as well as in everything) is actually always the same (fundementally).

It is energically favorible, ie, it minimizes the Lagragian. Everything that ever happens, must minimize the Lagragian.

Meaning: If x and y come into contact, and the difference between the "energy they have" and the " the energy they could have", can be made as small as possible if they do "z", then they will do "z". That is a fundemental law of the universe. It explains why particles annihilate, as well as why a balls rolls down a hill.

I mean I can try and relate it in terms of other physics concepts, if you specify the concepts. However, fundementally the answer will always be the same.

>>	Anonymous Wed Dec 29 00:50:55 2010 No.2265480 >>2265436 Someone answer this.

>>	Anonymous Wed Dec 29 00:52:55 2010 No.2265484 Yo physics guy. What would happen if the M87 galaxy collided with an Antimatter M87 galaxy?

Anonymous Wed Dec 29 00:54:55 2010 No.2265490

Sorry if this has been asked already, if so feel free to just pass over this question:

Why can't anything go faster than the speed of light? Is there any way you could succinctly explain what happens as an object approaches the speed of light and the reason it cannot reach/exceed the speed of light?

>>	Anonymous Wed Dec 29 00:57:55 2010 No.2265498 >>2265484 assuming they would not repel each other, BOOOOOM!!!!! matter+antimatter=100%efficient mass to energy conversion

Anonymous Wed Dec 29 01:00:55 2010 No.2265503

>>2265474
>The answer to "why" does "x and y" do "z" in particle physics (as well as in everything) is actually always the same (fundementally).
>It is energically favorible,

Yep, that's right, no endothermic processes ever.

>ie, it minimizes the Lagragian. Everything that ever happens, must minimize the Lagragian.

That's the time integral of the Lagrangian, and only when you fix the initial and final conditions. Not a very good explanatory tool until you do the math.

Anonymous Wed Dec 29 01:01:55 2010 No.2265507

>>2265490
the speed of light was found originally using limits, it is not an inclusive speed, similar to how 0 kelvin is not an inclusive temperature, as you approach the speed of light, your body begins to grow in apparent size, the limit is where the size=infinity

same as how 0 kelvin was discovered, pressure decreases as temperature decreases, exponentially, and once pressure would equal zero (cannot actually occur), that is 0 kelvin

>>	Anonymous Wed Dec 29 01:04:55 2010 No.2265514 >>2265264 Read his whole post before you criticize. >You need another particle to be involved in order to conserve momentum It's also right there in the wiki article you posted

Physics Guy Wed Dec 29 01:04:55 2010 No.2265515
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>>2265465
Ok, Ic, you are coming at this from a PEP chemistry point of view.

However, photons can penetrate PEP energy levels. There is some "highest energy level" you have. I could simply knock an electron off if.
Also, if I have a photon with the proper wavelength (energy), I can knock off electrons from the inner levels. (This happens in actual chemistry!)

I can keep doing shit like that, and make holes in the PEP structure. Consequently the Electrons will try and fill the holes, ejecting photons and energy out of the PEP structure. Just having a massive PEP structure does not seem to prohibit energy transfer.

Maybe I still don't understand what you are trying to say? Sorry.

>>	Anonymous Wed Dec 29 01:05:55 2010 No.2265516 >>2265507 FUCKING SCIENCE IS AWESOME. Thanks OP.

>>	Anonymous Wed Dec 29 01:05:55 2010 No.2265517 >>2265498 Mass is energy. There is no conversion. So what exactly is happening? I think I'm missing something.

>>	Anonymous Wed Dec 29 01:11:55 2010 No.2265529 >>2265517 mass is not actually energy, mass however does have a maximum potential energy (e=mc^2) it is a one way conversion, you cannot create matter from energy just the other way around

>>	Anonymous Wed Dec 29 01:11:55 2010 No.2265532 >>2265516 not op.....

>>	Anonymous Wed Dec 29 01:13:55 2010 No.2265534 >>2265484 probably not much as the distance between stars is much greater than the size of the stars themselves. Actual collisions of large bodies would be very rare.

. Wed Dec 29 01:15:55 2010 No.2265538

>>2265515

It's quite possible that my prof. was explaining something wrong or that I didn't quite understand his explanation correctly.

Let me try asking a similar but different question.

Why do I not fall through floors or push my hand through walls effortlessly if I could "knock holes in the PEP structure" in various manners then?

Is there more going on that just degeneracy and PEP?

>>	Anonymous Wed Dec 29 01:15:55 2010 No.2265539 File: 53 KB, 670x1461, 1275337159755155165.png [View same] [iqdb] [saucenao] [google] answer this you fucking faggot

>>	Anonymous Wed Dec 29 01:17:55 2010 No.2265545 >>2265534 depends on the type of galaxy normally you are right (there are 2 cluster galaxies currently passing through the milkyway) but when talking about the centers of spiral galaxies passing through eachother, alot of collisions would occur,

Anonymous Wed Dec 29 01:17:55 2010 No.2265547

>>2264901
I think that's the point. Maybe there's an equation that factors in the different energy levels.

Here's a question: can you explain 'curled up dimensions'? Would they have cyclical coordinates? I can't imagine them without imagining them taking up space in our 3 or 4D.

>>	Physics Guy Wed Dec 29 01:18:55 2010 No.2265550 >>2265539 E

>>	Anonymous Wed Dec 29 01:18:55 2010 No.2265553 >>2265538 that is because of the repulsive nature of the electromagnetic force nothing more or less, you are overcomplecating things if that is what you are asking

>>	Anonymous Wed Dec 29 01:20:55 2010 No.2265559 >>2265539 b/you would become light and not be able to stop so quit your belly aching hypotheticals

>>	Anonymous Wed Dec 29 01:20:55 2010 No.2265560 >>2265550 The fuck it is. The flashlight actively emits light, including at the starting point. It's B. The light intensity per unit of volume would be halved, but the length of the illuminated region would be doubled.

Anonymous Wed Dec 29 01:20:55 2010 No.2265561

>>2265490
It's how the universe works. We evolved to understand the world in terms of 3 spacial dimensions, and one of time. Well, that three plus one idea works, but time is not on equal footing with the three spacial dimensions. The short and mathematical answer is that the spacetime metric doesn't allow for it. The slightly longer explanation is that energy and momentum are the fundamental things in the universe, not position and speed so much. As you get closer to the speed of light, they start to become the same thing. So you're basically pushing your goal farther away from you the faster you go.

According to relativity, as you go faster, the rest of the universe seems to become more and more compressed as you go faster. As you're almost at the speed of light, the whole universe seems to be just a few meters long. If you were to go faster than the speed of light, where would the universe go?

Again, the metric is the correct answer, but this should give you an idea of how come instead of just a math number.

>>	Anonymous Wed Dec 29 01:21:55 2010 No.2265562 If I have sex with a chimp and I won't use condom can we have children? also, will they be like me? please answer this, it's important

>>	Anonymous Wed Dec 29 01:21:55 2010 No.2265563 >>2265507 Why does the mass increase with speed?

>>	Anonymous Wed Dec 29 01:22:55 2010 No.2265565 >>2265560 Or c, if you could run at the speed of light, but closer to option b.

>>	Physics Guy Wed Dec 29 01:22:55 2010 No.2265569 File: 4 KB, 126x96, 1283995545013.jpg [View same] [iqdb] [saucenao] [google] >>2265560 LOL I TROLL U U MAD BRAH?

>>	Anonymous Wed Dec 29 01:24:55 2010 No.2265571 >>2265561 i think you are confusing approaching the speed of light and falling into a black hole....

>>	Anonymous Wed Dec 29 01:25:55 2010 No.2265576 Is there a video series you reccomend to learn nearly everything?

>>	Anonymous Wed Dec 29 01:26:55 2010 No.2265580 File: 50 KB, 428x510, 1266188956903.jpg [View same] [iqdb] [saucenao] [google] >>2265539 >mfw someone reposts my OC

Anonymous Wed Dec 29 01:26:55 2010 No.2265582

>>2265563
mass doesnt increase, just the apparent size, e.g. if you look at 2 identical spaceships in the same distance from you, 1 is staying still and the other is approaching the speed of light, the moving one would seem to be significantly longer than the one staying still

Anonymous Wed Dec 29 01:26:55 2010 No.2265583

>>2265547
Think of it this way. You can walk around anywhere in your house. You could mark each point with a label of x,y, and z. Is that all you can do, move and stand in each point? No, you could face east, west, north, or south at any one of those positions. So if you had a party and had a bunch of people over, it wouldn't really do just to explain where they are standing (or sitting) in the house. It would be just as important to know which direction they are facing. So they have what physicists call an extra "degree of freedom." That's what these "curled up dimensions" are. Extra degrees of freedom.

Now, this is a bit of a bad analogy, don't take it too far. In this example, the extra degree of freedom comes from you being an extended, rigid body. So in that case, it's just a different configuration that gives the appearance of a new degree of freedom. In string theory, there's actually extra dimensions to move in, even for individual particles.

Physics Guy Wed Dec 29 01:29:55 2010 No.2265585
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>>2265514
LMAO, it is cool that you are debating. I think you are under the wrong impression though. I never said that "it was always possible for every photon (of every possible energy) to turn into a electron-positron pair". I simply ment it was a valid process.

Indeed, pair production from a single photon is very well documneted, and a valid process.

Of course, the transition has to obey certain conservation laws. (That is kinda a given). Hence the energy of the photon must be at least that of the mass of the electron and the positron, in order for the transition to occur.

I never specified this in the orginal post, case it wasn't relevent.

From wiki:
"Thus if the energy of the photon is high enough so that it can make the mass of an electron plus the mass of a positron (basically twice the mass of an electron which is 9.11 Ã— 10âˆ’31 kg) then an electron-positron pair may be created."

It then goes on to state that two photons could turn into an electron-positorn pair (again if there is enough energy to create the masses of the electron and positon). This can actually happen for any number of photons, electrons, and positons. The electrons and positrons always having to come in pairs, and the total energy of the photons need to be at least equal to the total mass of the electrons + positons created.

(Physicist often speak of mass/energy/momentum as the same unit, this is called natural units, sorry if it confuses you, http://en.wikipedia.org/wiki/Natural_units))

Anonymous Wed Dec 29 01:29:55 2010 No.2265586

>>2265562
> If I have sex with a chimp and I won't use condom

Don't get AIDS.

> can we have children?

Yes, but not with each other.

> also, will they be like me?

Your children, yes, they will be a lot like you, or rather 50% like you. Hers? Come to think of it, you'll probably have a lot in common, actually.

> please answer this, it's important

I'm going to assume this somehow will ensure world peace and end hunger. Do not prove me wrong.

>>	Anonymous Wed Dec 29 01:32:55 2010 No.2265597 >>2265585 But AH! You can have electrons with smaller energy if they are off shell. That being said, higher order processes are probably not something you want to have to try to explain over the internet.

Anonymous Wed Dec 29 01:32:55 2010 No.2265598

"All fields of the standard model and gravity are unified as an E8 principal bundle connection. A non-compact real form of the E8 Lie algebra has G2 and F4 subalgebras which break down to strong su(3), electroweak su(2) x u(1), gravitational so(3,1), the frame-Higgs, and three generations of fermions related by triality. The interactions and dynamics of these 1-form and Grassmann valued parts of an E8 superconnection are described by the curvature and action over a four dimensional base manifold."

what do we do with this information

>>	Anonymous Wed Dec 29 01:32:55 2010 No.2265599 OP is a wizard

>>	Anonymous Wed Dec 29 01:35:55 2010 No.2265606 >>2265385 please OP or anyone, at least say why this question is not worth of being answered..I think that onde from speed of light was way dumber and got answered

Anonymous Wed Dec 29 01:35:55 2010 No.2265608

>>2265585
>Of course, the transition has to obey certain conservation laws. (That is kinda a given). Hence the energy of the photon must be at least that of the mass of the electron and the positron, in order for the transition to occur.

Yeah, that and...
>You need another particle to be involved in order to conserve momentum

>>	Anonymous Wed Dec 29 01:35:55 2010 No.2265610 >>2265586 SIV can only become HIV once the human is already affected by SIV, eg you would need to have the infected chimp blood injected into you in a large quantity

Physics Guy Wed Dec 29 01:37:55 2010 No.2265611
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>>2265516
Yeah, that wasn't me. That was another Anon >>2265507 who answerd your post, nicely.

I can't really get to every post, but there are other people of 4chan who know physics too, so I appreciate anyone's input. THANKS

>>	Anonymous Wed Dec 29 01:38:55 2010 No.2265614 >>2265606 >>2265385 elaborate some, i am not familiar with the catastrophe you are talking about (unless i know it by another name) i want to say i know how to answer this but i am not familiar enough with the occurance to really answer

>>	Anonymous Wed Dec 29 01:39:55 2010 No.2265615 what is the big bang and what happened before it happened

Anonymous Wed Dec 29 01:40:55 2010 No.2265618

>>2265385
Classical physics predicts energy and temperature to go up continuously. If you integrate over all wavelengths (energies) you end up with an infinite amount of power. It is only once you discreetize in quantum physics that you have a cutoff point, which prevents the problem. If you don't understand the calculus behind this, wiki Gabriel's Horn.

>>	Physics Guy Wed Dec 29 01:40:55 2010 No.2265619 File: 62 KB, 489x419, 1267272137522.jpg [View same] [iqdb] [saucenao] [google] >>2265608 Read the whole article, you can't just jump around....lol. It is there for you.

>>	Anonymous Wed Dec 29 01:41:55 2010 No.2265621 Physics Guy, In symmetry breaking, are we introducing a new degree of freedom just to make the math work out nicely, or is there some potentially physical meaning to the extra degree of freedom?

>>	Nuclear Engineer guy Wed Dec 29 01:42:55 2010 No.2265623 decided i should give myself a name >>2265498 >>2265507 >>2265529 >>2265532 >>2265545 >>2265553 >>2265559 >>2265571 >>2265582 >>2265610 >>2265614

>>	Anonymous Wed Dec 29 01:42:55 2010 No.2265624 >>2265474 Ball rolls down hill because of gravity no?

>>	Anonymous Wed Dec 29 01:44:55 2010 No.2265629 If you are traveling in a straight line in a car at 20 m/s and you hold a gun out the window exactly level and perpendicular to the car and shoot it at 300 m/s and there is no gravity and air will the bullet go in a diagonal line?

>>	Nuclear Engineer guy Wed Dec 29 01:45:55 2010 No.2265634 >>2265621 just occams razor in action

>>	Anonymous Wed Dec 29 01:46:55 2010 No.2265640 Why is nuclear power hated so much when it's one of the best solutions?

>>	Anonymous Wed Dec 29 01:47:55 2010 No.2265642 >>2265585 So it must be possible to draw a Feynmann Diagram for single-photon pair-creation, then, right? Could you show me?

>>	Nuclear Engineer guy Wed Dec 29 01:47:55 2010 No.2265643 >>2265629 yes it would not be a very diagonal line, we are talking max 10degrees off of the perpendicular

Physics Guy Wed Dec 29 01:48:55 2010 No.2265646
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>>2265538
Actually, it is the PEP structure and the photon exchange that occurs between PEP structures that is responsible for the "electrostatic repulsion", the process that keeps you from going through the floor.

You could also think of it like this:
Macroscopically like charges repel.
The outer structures of atoms and molecules are all PEP electron structures (negativly charged structures), which repel eachother.

Nuclear Engineer guy Wed Dec 29 01:49:55 2010 No.2265651

>>2265640
i work at the savannah river nuclear facility (largest supplier of nuclear energy in usa) and i am flabergasted by this aswell, i blame white people and the cold war giving the term "nuclear" a bad name(politicians not actual white people)

>>	4tran Wed Dec 29 01:50:55 2010 No.2265656 Is it obvious why a fermion mass term sometimes (but not always) breaks gauge invariance? I remember this being a problem for U(1)xSU(2) electroweak theory, and they used the Higgs mechanism, etc. However, why wasn't this a problem for U(1) QED?

>>	Anonymous Wed Dec 29 01:51:55 2010 No.2265657 do you believe in the copenhagen interpretation or the MW interpretation

Anonymous Wed Dec 29 01:53:55 2010 No.2265665
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>>2265642
Photon -> Electron + Positron is first equation under examples on the wiki page. There is a whole paragraph about it. Are you trying to troll the PhysicGuy? Why?

>>	Nuclear Engineer guy Wed Dec 29 01:54:55 2010 No.2265670 >>2265657 I like the M theory because it is fanciful while still following occam's razor, though each are equally valid

Anonymous Wed Dec 29 01:55:55 2010 No.2265673

>>2265614 the thing is "The ultraviolet catastrophe, also called the Rayleigh-Jeans catastrophe, was a prediction of late 19th century/early 20th century classical physics that an ideal black body at thermal equilibrium will emit radiation with infinite power." from wikipedia.

>>	Anonymous Wed Dec 29 01:57:55 2010 No.2265682 Statistical physics: Why the natural log in S = k ln(W)? It seems like you could rewrite thermodynamics without the natural log and it would still work, although what we have defined as "temperature" would be quite different?

>>	Nuclear Engineer guy Wed Dec 29 01:59:55 2010 No.2265691 >>2265673 note where they say "thermal equilibrium" with special attention, this should make things a little clearer

Anonymous Wed Dec 29 02:00:55 2010 No.2265697
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I'm going to read this thread, but I just wanted to ask quickly in case you're almost leaving.

I'm starting a "general physics, calc" class (opposed to physics using algebra). Name 5 or less things that I should review in the next few days. Thanks ahead of time.

>>	Physics Guy Wed Dec 29 02:01:55 2010 No.2265700 File: 22 KB, 250x315, physics_today.jpg [View same] [iqdb] [saucenao] [google] >>2265624 "Gravity" is a type of "potential" energy, you could classify it as "the energy they could have" in the >>2265474 analogy.

>>	Anonymous Wed Dec 29 02:04:55 2010 No.2265707 >>2265691 No riddles plz.Explain like you would explay to a q 10 year old GIRL(if its to hard, it may be a 6 yo boy)

Anonymous Wed Dec 29 02:06:55 2010 No.2265716

>>2265619
Hey, I'm just pointing out that what
>>2265171
is correct. To turn a real (meaning on-shell) photon into a real electron-positron pair, you need some matter for the photon to interact with. Of course, this doesn't apply to the virtual pairs you also mentioned in
>>2265150

Nuclear Engineer guy Wed Dec 29 02:09:55 2010 No.2265722

>>2265697
basic integrals and derivatives in differentiating rates
e.g. look through the original process galileo/newton went through to find that the derivative of distance traveled(speed), and speed changing(acceleration) and watch how it all interacts in cases that acceleration is not constant (as if the function for acceleration were a quadratic equation in itself)

Physics Guy Wed Dec 29 02:11:55 2010 No.2265728
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>>2265697
Well, I would review Cal, not physics. If you don't know cal, then you should start studying cal, ASAP. If you already know cal, then study Cal 2. If you already know Cal 2, then study cal 3. Usually, basic gen physics, doens't use math higher then Cal 3.

They will teach you the physics, but they won't teach you the cal, and the more you have a fundemental understanding of cal the easier everything will be for you.

You can try to learn both cal and physics at the same time, but usually you end up lagging behind, and you will need cal that likly hasn't been taught yet.

Good Luck!

>>	Nuclear Engineer guy Wed Dec 29 02:12:55 2010 No.2265729 >>2265707 shit thats hard.....ummmmm cant you just say jesus did it?

>>	Anonymous Wed Dec 29 02:14:55 2010 No.2265733 >>2265716 Wow, that is the shittiest trolling I have ever seen. You must be really really sleepy right?

>>	Nuclear Engineer guy Wed Dec 29 02:15:55 2010 No.2265735 >>2265707 >>2265729 gimme a few mins to collect thoughts and i will try

>>	Anonymous Wed Dec 29 02:16:55 2010 No.2265738 File: 45 KB, 358x500, 5613_2ec7..jpg [View same] [iqdb] [saucenao] [google] >>2265722 >>2265697 here. This looks like gold, what you're saying. If you or anyone else wants to elaborate, I would love that. this is some tits.

>>	Anonymous Wed Dec 29 02:19:55 2010 No.2265749 >>2265729 it was a way to say... to a smart 18 yo boy.No jokes plz

>>	Anonymous Wed Dec 29 02:21:55 2010 No.2265752 225 posts and 63 image replies omitted. Click Reply to view. /sci/ you dissapoint. thought you had more sense than to feed the troll.

>>	Anonymous Wed Dec 29 02:22:55 2010 No.2265758 >>2265735 My point was just to avoid being vague..I just want a simple and complete answer, that requires no guessing from me, if possible

>>	Nuclear Engineer guy Wed Dec 29 02:25:55 2010 No.2265769 >>2265707 it's kinda like a limit theoretical, the thermal change is proportional only when assuming excess that is the most basic i can get, (then again it is 230 am here so my mind is at 4% of normal)

Physics Guy Wed Dec 29 02:26:55 2010 No.2265773
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Ok, well I'm gonna go. Thanks for the great questions /sci/. It is nice to talk about shit that interests you, as well as to educate/debate others.

I am pretty impressed by the lack of trolls. I never really seem to get them in these threads.
Thanks for behaving yourself.

I will leave you in the hands of the nobel "Nuclear engineering guy" >>2265735, or whoever else want to try an answer questions.

Happy new years!!!!

>>	Nuclear Engineer guy Wed Dec 29 02:28:55 2010 No.2265780 >>2265773 farewell

>>	Anonymous Wed Dec 29 02:29:55 2010 No.2265782 >>2265752 I stand corrected, you are the shittiest troll ever. I heard of phoning it in, but DAMM BRO!

>>	Anonymous Wed Dec 29 02:31:55 2010 No.2265786 >>2265773 Fuck you man, leave us with a fact. I don't need your new year bullshit. eq'n or gtfo

Anonymous Wed Dec 29 02:34:55 2010 No.2265794

>>2265769
"the thermal change is proportional only when assuming excess" proportional to what? excess of what? You dont need to be "basic", just to speak it all and dont let space for guessing.I've had undergraduete basic physics courses and math, I study computer science, thats my "reach"

>>	Anonymous Wed Dec 29 02:34:55 2010 No.2265795 >>2265782 troll troll troll your boat all the way through /sci/ when someone points out you're wrong don't forget to cry

>>	Anonymous Wed Dec 29 02:35:55 2010 No.2265798 File: 25 KB, 417x525, 6798756865865865.jpg [View same] [iqdb] [saucenao] [google] >>2265773 KING OF SCI

Nuclear Engineer guy Wed Dec 29 02:36:55 2010 No.2265801

>>2265738
>>2265738
eh, like here is a sample problem:
a ball is accelerating down hill at 5t^3+7t^2+8 m/s^2
what is it's instantaneous speed at t=4

also look between the transition via calc between

x=x(original)+vt+.5at^2
its derivitive v=v+at
and the derivative of that a=a

>>	Anonymous Wed Dec 29 02:38:55 2010 No.2265803 File: 70 KB, 405x348, 1277424828066.jpg [View same] [iqdb] [saucenao] [google] >>2264445 nice thread

>>	Nuclear Engineer guy Wed Dec 29 02:41:55 2010 No.2265812 >>2265794 sorry i have a feeling that my jumbled up sleepy talk wont go very far, i found a link to a pretty detailed look at the phenomena that you have probably already seen http://spiff.rit.edu/classes/phys314/lectures/planck/planck.html

>>	Anonymous Wed Dec 29 02:44:55 2010 No.2265815 >>2265773 how do you get all this information to stick inside your head? fuuuu

>>	Nuclear Engineer guy Wed Dec 29 02:44:55 2010 No.2265818 looks like the thread just died when physics guy left, im gonna refresh the page in a couple mins and if nothing has changed im gonna take my sleepy self back to bed

>>	Anonymous Wed Dec 29 02:46:55 2010 No.2265822 >>2265818 and nothing of value was lost?

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 02:47:55 2010 No.2265825 >>2265818 it's late for most of /sci/ post rates drop for the next 5 hours. you won't find much interesting discussion later tonight.

>>	Anonymous Wed Dec 29 02:48:55 2010 No.2265829 >>2265665 prove that the perimeter of a circle isn't the diameter * 4

Anonymous Wed Dec 29 02:48:55 2010 No.2265830

>>2265665
Wiki page for what? if you mean for "Feymann Diagram" then no, it isn't. If you mean "Pair production" then there is no Feynamm Diagram.

Still, show me a *valid* Feynmann Diagram that shows an interaction with one photon in and an electron-positron pair out.

>>	Anonymous Wed Dec 29 02:50:55 2010 No.2265831 Is it possible to network a 10 Farad capacitor and a 15 Farad capacitor to make a 25 Farad capacitor?

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 02:53:55 2010 No.2265835 >>2265831 in parallel, that's easy.

>>	Nuclear Engineer guy Wed Dec 29 02:53:55 2010 No.2265838 >>2265831 no dont try it, when i was younger i wondered the same thing and ended up having 4 10 farrad capacitors blow in my face, it hurts.....

>>	Anonymous Wed Dec 29 02:56:55 2010 No.2265841 >>2265830 Damn you, conservation of momentum!

Anonymous Wed Dec 29 02:56:55 2010 No.2265843

>>2265835
Really? Because I figured if it went
Energy------>10F------->15F------->output
then wouldn't the 10F release into the 15F giving it 10F/15F then after the 10F released again the second would release 15F and fill with 5F/15F which would mean it isn't a 25F capacitor, but a 15F capacitor?

>>	Anonymous Wed Dec 29 02:58:55 2010 No.2265847 Serious one. Is matter continuous?

>>	Anonymous Wed Dec 29 03:00:55 2010 No.2265852 >>2265843 My bad, I missed in parralel.

>>	Nuclear Engineer guy Wed Dec 29 03:00:55 2010 No.2265853 >>2265843 yes and if you were the dumbass i was you would place the 10f capacitors behind the 15f capacitor accidently and the row of 10f capacitors would blow and give you salt/steam burns

>>	Anonymous Wed Dec 29 03:01:55 2010 No.2265854 >>2265847 Why would anyone think that? Did you learn about atoms?

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:02:55 2010 No.2265857 >>2265843 capcitors work "opposite" resistors. so you line them in parallel when you want them to add, and in series when you want 1/their capacitances to add. >>2265838 did you find out why?

>>	Nuclear Engineer guy Wed Dec 29 03:03:55 2010 No.2265860 >>2265847 lulz, i needed that

>>	Nuclear Engineer guy Wed Dec 29 03:06:55 2010 No.2265868 >>2265857 honestly, that incident was in college and since then i avoid all circuitry and focus on my major/master (mech engineer/nuclear engineer) i understand circuitry but i avoid experimentation at all costs

Anonymous Wed Dec 29 03:12:55 2010 No.2265886

>>2265838
Actually I just said 15F to simplify it, really I'm working with 2.2mF and .3mF capacitors and trying to make a 2.5mF capacitor because mouser doesn't offer it.
>>2265857
I have another question
wouldn't it be flawed in parrallel too?

once the input has put 10F in both capacitors wouldn't the the first release and the second still have 5F to go? Making it a 10F then 5F then 15F capacitor?

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:12:55 2010 No.2265888 >>2265868 that's disappointing. Science should be repeatable. Oh well, i'm even further from experimentation than you are, so I'm not one to talk.

Anonymous Wed Dec 29 03:13:55 2010 No.2265890

>>2265854

Atoms don't really apply here. If matter is made up particles, and particles are represented by wavefunctions, and wavefunctions are defined at least slightly over all space (they are never actually zero), the don't all wavefunctions overlap and nothing can be precisely localized.

I know that things can be practically and precisely localized because wavefunctions fall of toward zero quickly after certain potential barriers, but because they are never zero, matter is continuous, right?

Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:16:55 2010 No.2265899

>>2265886
in parallel should work just fine. They discharge simultaneously. and evenly, so the voltage in the loop is even. even if you somehow thought of discharging them one at a time, first you would get 10F, then you'd get 15F. total of 25.
I have an odd intuitive reluctance about mixing such different capacitances, but there's no theoretical problem with it that I know of.

>>	Anonymous Wed Dec 29 03:17:55 2010 No.2265904 >>2265899 But if they gain energy at the same rate and one releases energy at 10F while the other does it at 15F then why would they release simultaneously?

Anonymous Wed Dec 29 03:18:55 2010 No.2265906

>>2265890
That's a waaaay overgeneralization. You are right to say that wavefunction overlap only tends to zero rather go to exactly zero, but I don't think you appreciate how strong exponential suppression is. Atoms really do behave as islands. Probably a good example is how sugar can flow like a continuous medium.

>>	Anonymous Wed Dec 29 03:18:55 2010 No.2265910 >>2265899 >discharge evenly wot?

>>	Anonymous Wed Dec 29 03:20:55 2010 No.2265913 >>2265906 I said that they can be practically localized, but speaking absolutely and exactly, isn't matter continuous, since every wavefunction overlaps with every other wavefunction, even if the overlap is just infinitesmally small?

>>	Anonymous Wed Dec 29 03:20:55 2010 No.2265914 >first you would get 10F, then you'd get 15F. total of 25 >Doesn't understand the purpose of a capacitor

>>	Nuclear Engineer guy Wed Dec 29 03:22:55 2010 No.2265920 >>2265906 >>2265906 stop feeding the troll

>>	Anonymous Wed Dec 29 03:25:55 2010 No.2265925 I still haven't had my question answered. Why would a parallel circuit work with different capacitors?

Anonymous Wed Dec 29 03:27:55 2010 No.2265929

>>2265920

Or just answer my question.

The wavefunction of every particle is non-zero everywhere. Yes, it tends (very) quickly to zero, but never reaches it. Thus each wavefunction over laps each other one, thus instead of completely discrete particles, strictly speaking matter is continuous.

Again, I realize that because it drops toward zero so quickly, that we can practically say that certain particles are localized, but I'm not talking about practically. I want to know strictly speaking, yes or no.

>>	Anonymous Wed Dec 29 03:29:55 2010 No.2265936 >>2265929 no because matter is PARTICLES which have mass.

Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:29:55 2010 No.2265937

>>2265914
don't care about purpose of capacitor, i just know how it works electrically. Also, it should be clear from context that I know that isn't how they actually work.

>>2265904
>>2265910
in every loop in every circuit, the net voltage is zero. The voltage of a capacitor is given by Q=CV
or v=Q/C, where q is the charge on the capacitor and C is the capacitance of the capacitor
so v1=v2 for the two capacitors in parallel
so Q1/C1=Q2/C2
since C1 and C2 are constants, we get the result:
Q1/Q2=constant
so the charge (q) on each one will decrease (and increase) proportionally to the other one. I called this "evenly' discharging and "simultaneous" release of charge/energy.

Hopefully this is perfectly clear, any further assertions that I'm wrong on this point will be regarded as trolling, and promptly ignored.

>>	Anonymous Wed Dec 29 03:30:55 2010 No.2265939 >>2265936 And particles with mass must still be described with wavefunctions...so what I'm saying still stands...

>>	Anonymous Wed Dec 29 03:31:55 2010 No.2265943 >>2265936 lol seriously he said "particle" like 40 times.

>>	Anonymous Wed Dec 29 03:33:55 2010 No.2265948 >>2265937 troll troll troll your boat through the whole of /sci/ when your corrected change your trip nobody will question why

>>	Anonymous Wed Dec 29 03:37:55 2010 No.2265955 File: 2 KB, 271x85, Untitled.png [View same] [iqdb] [saucenao] [google] >>2265937 This is what you're talking about right? Explain in lahmens terms why the one that can hold more gets more energy.

Another Physics Guy Wed Dec 29 03:40:55 2010 No.2265962

>>2265890
It depends upon the conditions and the details of the quantum system. If we're talking about a system of discrete particles, like Helium gas in a box, then the volume per particle is a function depending on system temperature - that is, the internal energy of the constituent helium atoms. Below a certain temperature, the volume-per-particle exceeds the distance between particles and their wavefunctions superpose indistinguishably and the system behaves like, as one extended quantum state. In that sense, the *wavefunction* encoding the *state* is continuous, but interacting with the system to perform a measurement will still locate a Helium atom to a spatial region which could have arbitrarily small volume, if you like, depending on the physical measurement conditions imposed.

If you're talking about molecular systems, it becomes less defined. In the case of a saturated carbon chain, the bonds between any two carbon atoms are of course quantum systems (molecular orbitals, defined by wavefunctions). If the system is aromatic or has a conjugated double-bond (pi) system, then the electrons form a quantum system that is as long in spatial extent as the uninterrupted conjugated system. Again, in this sense the electron wavefunctions for the p-orbitals are continuous over some region of space, but measurement could define a location for any individual electron consistent with the wavefunction, to almost arbitrary exactness.

Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:42:55 2010 No.2265966

>>2265955
if you have two tunnels on a road, and one is 7 lanes and the other is 2 lanes, most cars will go into the 7 lane one. But it will begin to back up, because you need to have 9 full lanes of traffic.
so some goes in the 2 lane tunnel. But this backs up quickly, so doesn't get very much before people start switching back to the 7 lane tunnel.

But in capacitors, this is continuous, where each one gets the "right" amount all the time. And the cars never get out of the tunnel, ever. The only way for them to come out is to go back the same way they came, once the current is reversed.

Cars=electrons
tunnels=capacitors.

>>	Anonymous Wed Dec 29 03:44:55 2010 No.2265968 If I touch both ends of a battery, isn't the current going through my body? Why don't I feel shit?

Anonymous Wed Dec 29 03:44:55 2010 No.2265969
File: 81 KB, 601x599, 601px-Rotas_square_from_Cirencester.jpg [View same] [iqdb] [saucenao] [google]

>>2265529
How do you distinguish? Mass increases with energy and vice versa. Even potential energy increases mass.

I saw an example of a nuke going off in an indestructible box. Lots of heat obviously, but the box weighs exactly the same. I'm not quite understanding where that heat comes from.

>>	Another Physics Guy Wed Dec 29 03:46:55 2010 No.2265974 >>2265962 Upon measurement, electrons are point-like. As are the other leptons; and as are quarks. Even if their wavefunctions decay to zero only at infinity.

>>	Anonymous Wed Dec 29 03:46:55 2010 No.2265975 >>2265968 the word for today is resistance, spelt R-E-S-I-S-T-A-N-C-E.

>>	Anonymous Wed Dec 29 03:46:55 2010 No.2265977 >>2265913 >I said that it is practically 1, but speaking absolutely and exactly, isn't 0.9999... !=1, since every number is 9 all the way down, simply tending to 1?

>>	Anonymous Wed Dec 29 03:49:55 2010 No.2265982 >>2265966 So does it look like this? Sorry for hot linking on an image board. http://www.regentsprep.org/regents/physics/phys03/bparcir/parallel.gif Except with the water wheel looking thing stopping until it gets the right amount of electrons?

Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:50:55 2010 No.2265984

>>2265968
V=IR
say you choose a 9V battery.
Your resitance will be amazingly high.
"Under dry conditions, the resistance offered by the human body may be as high as 100,000 Ohms. Wet or broken skin may drop the body's resistance to 1,000 Ohms,"
so you get .0009 amps of current. which is .9 milliamps. Wikipedia says the minimum current you can feel is 1 milliamp
So get a 12 volt battery, take it with you into the shower and you might feel something.
Maybe trolling with that last bit.

>>	Anonymous Wed Dec 29 03:51:55 2010 No.2265985 >>2265977 It isn't .9999... thought. Also I'm not the guy who brought this up.

Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 03:54:55 2010 No.2265995

>>2265982
those are resistors, which do not behave like capacitors. Until you get pretty deep (or however deep impedances are).

I don't really like that drawing very much. It's not wrong, just not good. But if you take 1/listed number, then you'll get it right for capacitors. The number of charges flowing is proportional to the Capacitance, whereas in a resistor, the number of charges flowing is proportional to 1/the Resistance.

Another Physics Guy Wed Dec 29 03:55:55 2010 No.2265996

>>2265962
...And the wavefunctions are unphysical entities that only exist in a mathematical space involving imaginary numbers. Yes, the square of the wavefunctions are more real, in a sense, but remember they describe the probability distribution field from which particles can define a point-like location upon interaction of the wavefunction with the external world.

>>	Anonymous Wed Dec 29 03:56:55 2010 No.2266003 >>2265977 What? No. I said a small overlap. For example maybe an two electrons wavefunctions on two seperate atoms on oppsite sides of the room might have a psi^2 overlap of 0.000-thousad zeroes here-000 %

>>	Another Physics Guy Wed Dec 29 03:57:55 2010 No.2266004 >>2265529 Wrong. http://en.wikipedia.org/wiki/Pair_production

>>	Anonymous Wed Dec 29 03:58:55 2010 No.2266006 >>2265995 Okay, thank you

>>	Anonymous Wed Dec 29 03:58:55 2010 No.2266007 >>2266003 add a 1 at the end of my number. Sorry.

>>	Anonymous Wed Dec 29 03:59:55 2010 No.2266013 >>2265996 That's only if the wavefunction collapses. Particles have wave behavior as well, so in that sense, wavefunctons are physical entities

Another Physics Guy Wed Dec 29 04:00:55 2010 No.2266015

>>2266003
The probabilities associated with finding an electron out at the other side of the room would be such that you could do a measurement every nanosecond for the age of the Universe and it would have never happened.

Really, concerning the electron wavefunctions of atomic systems, "the other side of the room = infinity", for all practicaly purposes.

Anonymous Wed Dec 29 04:00:55 2010 No.2266016
File: 84 KB, 700x500, 1F92358CFF0105F1BA4D8BDB1EE6.jpg [View same] [iqdb] [saucenao] [google]

>>2264779
"Well, with the exception of string theory, not much has happened since the 1930â€™s, and you canâ€™t prove string theory, at best you can say â€œ... hey, look, my idea has an internal logical consistency.â€"

>>	Anonymous Wed Dec 29 04:12:55 2010 No.2266038 File: 105 KB, 955x637, 1289106183289.jpg [View same] [iqdb] [saucenao] [google] >>2265529 MFW when I convert to creationism so I can at least get consistent bullshit.

>>	Anonymous Wed Dec 29 04:21:55 2010 No.2266053 >>2265529 I'm sorry..... E=mc^2 m= E/(c^2) Energy can be turned into mass..... this is the simplest explanation for it possible I'm pretty sure

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 04:23:55 2010 No.2266055 >>2265529 it seems researchers are creating positrons from energy quite happily. or at least, that's what some press releases say. positrons are mass, no?

>>	Anonymous Wed Dec 29 04:25:55 2010 No.2266058 >>2266055 Not to mention, the LHC... inb4 POSITRONS ARE ANTIMASS

>>	Anonymous Wed Dec 29 04:28:55 2010 No.2266061 >>2266058 Positrons are antimass!

>>	Î¼Î±Î¸Î¼Î±Î½ - the enlightened undergraduate !!vnLoxcfyRGs Wed Dec 29 04:30:55 2010 No.2266066 >>2266061 facepalm

>>	Anonymous Wed Dec 29 04:31:55 2010 No.2266067 >>2266066 trollface.jpg

>>	Anonymous Wed Dec 29 04:34:55 2010 No.2266074 Is there a difference between the LT1086 and the LD1086 power ICs?

>>	Anonymous Wed Dec 29 04:36:55 2010 No.2266081 If negative weight doesn't exist then how do helium balloons work?

Anonymous Wed Dec 29 04:49:55 2010 No.2266100

>>2266055
Yes, it goes both ways, but what is energy except agitated particles? Mass of an object increases with energy. Don't know where I'm going with this.

Could it be said that matter such as arranged in a molecular structure (seems like a sensible definition) converts to heat? Mass and energy is equivalent and conserved but maybe the distinction I'm looking at is only in the macrostate (heat).

Am I sense?

Anonymous Wed Dec 29 04:56:55 2010 No.2266107
File: 97 KB, 500x631, 1292746143107.jpg [View same] [iqdb] [saucenao] [google]

>>2265700

Ok. So I still don't understand why they annihilate each other. Or rather why, can you answer HOW they annihilate each other?

Is it something similar to fission or fusion?

>>	Anonymous Wed Dec 29 08:35:55 2010 No.2266522 Blimp.

>>	Anonymous Wed Dec 29 12:24:55 2010 No.2267044 >>2265385 still, someone would answer this?

>>	Anonymous Wed Dec 29 14:37:55 2010 No.2267387 ok

>>	Anonymous Wed Dec 29 16:13:55 2010 No.2267672 Bumping this epic thread for morningfags.

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