Hey Physics Guys

[PatsFanInVa]

Me, I'm a big fan of what guys who know their math say about the very big and the very small, and just bent my mind with what I call YMPP, or Yet More Popularized Physics... specifically Leonard Susskind's The Black Hole War: My Battle With Stephen Hawking To Make The World Safe For Quantum Mechanics.

For the religious, I'd like to dispose of the normal "personal God", "Heaven and Hell," "It's All Just Theory Cuz Its Too Little To See" nonsense...

I'm open to more advanced pondering from a religious POV, but no dumb argument for its own sake, please.

For our mathy guys, I'd like to kick off what I hope will be a discussion of SOME sort with the awe in which I hold both the fuzzier and the more accepted scientific principles currently evolving... I'd love to raise a specific point, but from the outset our only real point is that it all just is, in terms of the physical sciences -- I am, however, in awe of what just is, regardless of any religious flight of fancy.

I'm also struck by the similarity between physical dualities (observer/participant in particular,) and the divide between the objective and the subjective I've discussed here in the past. But that's probably internal to my own point of view.

Finally it was cool to finally have someone explain the uncertainty principle in terms of the "fuzzy focus" wavelength you use to get velocity of a particle and the very high energy wavelength you have to use to pinpoint position, and the very real way that the latter must perturb the object under study. Until I read this particular book, the uncertainty principle seemed like some vague mystical thing. Now it makes a lot more sense.

At any rate I'd love for the physics guys to open up on these topics, assuming that the more Goddy members of our forum agree to tread lightly, myself included.

Dying to see what comes of it.

PFnV

 

[FirstAndGoal]

Read any book by Feynman

Amazon.com: Richard Feynman


What topics are you interested in? I have a background in quantum mechanics. It sounds like you're starting to understand the collapse of the wave (Schrödinger's cat) but that's just the beginning.

 

[PatsFanInVa]

1st and G, pretty much all of it. Susskind oozed with admiration for Feynman by the way. But then he did a lot of namedropping LOL...

What can I say? I'm fascinated by the subject but a comparative unlettered savage. This particular book was about resolving the problem of information loss in black hole evaporation, which Hawking maintained truly happened, and which Susskind et al. eventually "established" (to the extent the question could be settled) that the information isn't lost, but contained in a theoretically reconstructable form in the Hawking radiation at the horizon.)

So I sort of whizzed through very basic string theory (the interesting teeny ones and the big fat mundane ones in nucleons,) the holographic principle (uh, please tell me that we're only saying the three-dimensional volume can be described by a 2D hologram projected from an imaginary boundary... not that it is one...) a tiny bit about quantum mechanics... a little classic relativity, for the nth time, etc.

What I liked was that it stretched my brain at times, spared me most of the equations, and gave me a feeling (no doubt illusory) that I "got it." Does Feynman have that same gift for dare I say it, dumbing it down?

PS - I've heard the terminology "collapsing of the wave" before but do not get the specifics of what that means. In this latest little foray it did not come into play. I get why we're uncertain, but I don't get what a wave has to do with it, other than that the most inobtrusive observation we can do is a single photon, and that though "massless," at a high frequency it packs too much of a punch and therefore would knock our particle off its path, if we want velocity at the same time as position (or would give us very fuzzy position if we reduce the frequency so as not to knock around the subject particle.) But the "collapsing of the wave" is a mystery phrase to me, in terms of the physical explanation. I do understand that "the wave" is considered to have "collapsed" when one state is observed to be the case (i.e., the cat observed as alive or dead.) What wave do we mean here exactly? Something tells me it's a description of a probability function, not a physical wave. Help me out.

 

[patsfan13]

Feynman is great at taking the 'complex' and describing it in a way that others can uinderstand. A lot of math in his lectures. The Feynman Series has been a staple supplemental text for Freshman Physics majors for many years.



In QM particle is described as a wave, particle has position and momentum, Uncertainly principle states you can only know the position and momentum to a certain degree. In the process of measuring (observing) a particle the more you know about the position the less you know about the momentum, and vice versa. The limit is set by the eq in Heisenberg's uncertainty principle.


From the religious angle it maps into Bhuddism or Taoism more readily thatn Judeo Christian principles.

 

[Tunescribe]

There's a really interesting documentary/docudrama on DVD called "What the Bleep Do We Know?" in which some of the world's foremost quantum theorists (and others) discuss scientific evidence supporting the existence of God/spirituality. Has anyone else here seen it?

 

[PatsFanInVa]

Tune, I have not, though I am leery of claims of scientific "evidence" on this subject. I do have a good deal of respect of the notion that we can describe all of this as information, for example, or delve deep into matter/energy equivalency and things always being built of littler things, and describe everything as something else's thought, or more to the point, as thinking, whether or not we name the someone/something else. Thought therefore thinking, not cogito ergo sum.

Beyond that people have made a lot of the idea that we cannot simultaneously observe a particle's position and velocity, because by observing we influence it... but I think people go way too far with this. For instance, we say "as long as we do not look at the particle its behavior has not been changed," when as far as I can see, the Uncertainty Principal just tells us the limits of our perception based on very easily understood (even by us classically wired retahds) mechanical problems. That is, by way of metaphor, that it's not my observation of the thing that changes it, it's turning on the light to look at it; my eyesight is a passive system. It just doesn't work without lighting. It's the energy of the light that changes things, not the fact that I'm looking.

So... would love to see the film, but I hope I don't end up with the notion that once we're conscious we control the world because we observe it. A big dumb photon factory like a star does much more influencing by bombarding everything with energetic particles, photons included. Our interpretive minds or our habit of observing, unless I'm missing something, does not actually cause anything in this interaction. We simply cannot use that predilection to observe things without also influencing them... and that's a different kettle of fish

PFnV

 

[patsfan13]

If you want another take on the observed/observer issue check out Bell's theorem.

 

[The Brandon Five]

I thought this was pretty interesting:

Wave Function Directly Measured - Science News

The fuzzy quantum shape that describes the speed or location of a single particle, its wave function, has now been directly measured in the laboratory, giving this mathematical concept a small dose of reality.

Like a bubble on the breeze, the wave function usually disappears when poked or prodded for information. But scientists in Canada have worked out a gentler way to touch it, they report June 9 in Nature.
...
Lundeen and his colleagues aren’t trying to challenge quantum mechanics. Heisenberg’s uncertainty principle, which says that the location and momentum of a single particle can’t be simultaneously measured, still holds: Lundeen’s team had to weakly measure many light particles to work out the position information.

And all these light particles had to be identical, which could limit the usefulness of the technique.

“The method reported works only if one knows beforehand that every photon is created in the same quantum state,” says Michael Raymer, a physicist at the University of Oregon in Eugene. “This is generally not the case, and in this case one would need to use the standard methods of quantum state tomography.”

Still, Lundeen says this new probe can probably be adapted to measure the wave functions of many other particles — including ions, molecules and electrons.

 

[TheSolderKing]

ask Bill Nye damn it!!!

http://www.youtube.com/watch?v=cCxgcWXxE4I Theme

Bill Nye stance on Pluto- YouTube - ‪Bill Nye the Science Guy on Pluto‬‏

 

[PatsFanInVa]

Started watching "Through the Wormhole," just by the way. The whole black hole war showed up as an episode, much to my delight.

 

[TheSolderKing]

ask Bill Nye:rocker:

 

[The Brandon Five]

Existence of God particle to be decided by next year - Telegraph

It has been speculated upon for decades and at the weekend there were hints that the existence of the highly sought-after “God particle” had finally been confirmed.

But at a press conference on Monday, the physicists in charge of the Large Hadron Collider said that they had only established where the Higgs boson was not to be found, and that its location continues to elude them.

However they added that as the amount of data created by the atom-smashing experiments increases, they now expect to know whether or not the most-wanted particle exists within 18 months.

If it is tracked down, it will explain how particles come to have mass and provide the final piece in the Standard Model of physics that was first set out in the 1970s, while if it turns out not to exist then the textbooks could be ripped up.

Rolf-Dieter Heuer, director general of the European Organisation for Nuclear Research (Cern), told reporters: “I would say we can settle the question of the Higgs boson, the Shakespearean question ‘to be or not to be’ at the end of next year.”