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Metaphysics, Angels And Quantum Theory

Enki — Mon, 09 Nov 2009 20:53:08 -0800

Could a plausible theory be extrapolated for Angels/Paranormal Activity being an aspect of Quantum Physics? I'm doing research for a creative writing project, so a theory would only need to be plausible; the rest could be creatively expanded upon to make relative sense. I'd like to have the initial idea be based on something potentially possible, though.

Bill Nye should be a Mefite.

Christ, what an asshole — Mon, 06 Jul 2009 07:13:46 -0800

What are some simple experiments that help explain complicated phenomena? I was at a geology museum last year, and they had an exhibit where water slowly trickled down an embankment of sand. The path the water took was a seemingly random assortment of forks and zigzags. The accompanying placard read, "This is how Earth's rivers were formed over millions of years." The kid in me just went, "OHHHH!!"

When I was 7, my older brother challenged me to a bet of what would hit the ground first if dropped from the same height (a tie would mean I was wrong): a sandbag or a pen cap. I lost a dollar. Then two. Three. Then he offered to let me try. Four dollars. Five. I quit in frustration. Then came back when he left and kept trying for a half hour, and I thought I was going insane. When 3rd grade rolled around and we began learning about gravity in science class, I was well ahead of the curve, $5 poorer yet $5 wiser.

During Seder this year, my cousins were presented with the Monty Hall problem, and after at least 30 mins. of discussion, they still would not budge on the odds being 50/50. So I came up with this experiment. "I'm going to write down a number between 1 and 1 million. Try to guess it. Can we all agree that you have a 1 in a million chance of getting it right?" (Yes.) The guess was 23. "Alright, I'm going to eliminate numbers 1 through 22, 24 through 625,624, and numbers 625,626 through 1 million. Now would you like to stick with your original guess, 23, or switch your answer to 625,625?" Their eyes lit up. Well, at least three of them. My fourth cousin stubbornly stood by 23. I challenged her to try being the "host," and halfway through, it clicked, and she started damning herself.

What other interesting concepts or phenomena can be broken down in simple terms/experimentation?

What's a Particle Friend?

maryh — Sun, 07 Jun 2009 01:43:07 -0800

What is a "particle friend"? I assume this has some connection to quantum physics, but I've seen it used lately in broader sense. Can anyone explain?

quantum pathology

nihlton — Thu, 20 Dec 2007 12:55:00 -0800

quantum physics. what am I not getting? my understanding of quantum physics is that on the really small scale, our traditional laws of physics aren't so cut and dry so we had to develop probability models for how stuff will behave in order to make testable predictions. is that even approaching accurate?

if its not pretend my question is a request for a layman's explanation for quantum physics. If its close enough, read on for my actual question...

isn't that kind of lazy science?

I mean, my understanding is that in traditional physics, nothing is random. coin tosses, dice rolls, all of it can be predicted if you've got enough data. seems counterintuitive that this would change just because you're getting really small.

appearances aside - it seems to me sort of defeatist to say "stuff happens that we don't expect. there is no way we can know how or why, so lets just gather enough data to be able to say how its probably going to happen next time" Like if we never understood how gangrene happened, but instead of searching for the cause, we developed a probabilistic model for how and when it would strike. quantum pathology? that would never fly.

are we even still looking for the forces or effects that cause discrepancies at the quantum scale?

I don't know, maybe this question is silly and I don't understand the science well enough, but it seems like just declaring something unknowable and moving on isn't very scientific at all.

Need help for Formalisms in Quantum Physics

kureshii — Wed, 24 Oct 2007 09:40:29 -0800

I badly need help on formalisms in Quantum Mechanics! I just read this post from 2 years ago, and it did help a little, but not really enough. Story in short: I'm an aerospace engineering second-year, the pioneer batch of a trial academic program at my university. Suffice to say that additional requirements were put on us, and due to some poor course planning on the part of the administrators (don't ask) I'm almost at the end of a semester which saw me taking Linear Algebra I, II and Quantum Mechanics I simultaneously, without any prior knowledge/training in either of them.

Needless to say I'm not doing too well; I'm not too concerned about my grade - I should do well enough to pass, but I'd like to go further than that by the time the exams roll around in... about 4 weeks.

I'm just past the Schrodinger equations and recently started on formalisms for personal revision (about 6 lectures behind the course), and while the initial part was manageable I'm now deep under in Hilbert Space and Hermitian operators (x & iD), Fourier transforms and the like. I know it's not actually this hard; much of it seems like it should be intuitive and easily understandable if framed in the right context.

I know I should seek out my lecturer, but he isn't a great communicator by any measure, and while I'm pretty sure he's competent in the subject I can never understand anything he says. I am currently reading Introduction to Quantum Mechanics by David Griffiths, which has been quite a big help but still a little inaccessible for someone who's only spent 10 weeks on linear algebra thus far.

Finally, my query: Does anyone know of resources (preferably online) that greatly aids in understanding formalisms in the context of quantum physics? I know from personal experience that there is no substitute for practice, but with 4 weeks left to go I fear my revision isn't proceeding quickly enough, and I believe that some enlightening perspectives will help speed up my pace of revision.

I hope not to have to buy another textbook at this point; I won't be taking Quantum II next semester. While this will likely not be my last encounter with quantum physics, my future needs in this area are probably application-based (engineering-oriented) and not so theoretical, and spending that kind of money isn't really justified IMO. I'd seek out a library or cheap ebooks, but not anything more than that.

I know I'm trying to seek an easy way out of this mess, but if anyone can post something that helps I will be immensely thankful.

What is the most direct way I can learn all about quantum physics?

MetaMonkey — Wed, 29 Nov 2006 06:22:02 -0800

What is the most direct way I can learn all about quantum physics? I've read a couple of general books like The Tao of Physics, but I'd like to have a more thorough understanding than this. I was quite handy with maths and physics in school, but it's been a while since then. I'm not in any hurry, so I'm willing to do the learning over a period of time.

Quantum Aether -- brilliant or bunk?

greatgefilte — Mon, 05 Jun 2006 11:07:43 -0800

Quantum Aether -- brilliant or bunk? Just noticed a press release on EurekAlert from these guys. Obviously they're a bit more sophisticated than the Time Cube folks, but is there anything to it, or is this just another iteration of cold fusion?

atomchip real or hoax?

blueyellow — Fri, 06 Jan 2006 14:48:35 -0800

Is the atom chip vaporware? A few months ago there was a great deal of speculation about whether the quantum-optical computers from atomchip.com were real or a hoax. They are supposed to be presenting their product at the current CES 2006, but I can not find any coverage. Does anyone have any new infromation?

Physics Curriculum

mischief — Wed, 22 Sep 2004 21:55:43 -0800

PhysicsFilter: Some years ago, I heard of an undergraduate curriculum that introduced physics at the quantum level using linear algebra and that did not reach classical mechanics until late in the second semester. From an educational perspective, this method is supposedly more intuitive. What textbooks employ this teaching method?

State of Quantum Physics

evinrude — Thu, 18 Dec 2003 22:13:25 -0800

I'd like to read a readable, yet not dumbed-down account of the current state of quantum physics, addressing the famous paradoxes and directions modern research is taking. Any recommendations? [more inside] I'm a mathematician by training but not a physicist, and I'm inspired to ask this question because I just finished reading Paradigms Lost (and its sequel) by John L. Casti and found his explanations less than clear. I'm not sure if this was my fault or his. I guess I'm probably looking for something less technical than a journal article, but more rigorous than the science section of the New York Times. Please help me!