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Permalink Reply by Jeff H on November 19, 2009 at 8:04pm

You've been reading too much Stephen King... (One of the best opening lines in fiction..."The man in black fled across the desert, and the gunslinger followed.")

James S Saint said:

"“We may soon find that our whole universe isn’t even at the cosmic center.”""

Our entire universe is but a single drop of water that fell upon an ocean with a splash. And the entirety of that splash is merely a single grain of sand in an ocean of desert.

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Permalink Reply by James S Saint on November 19, 2009 at 9:03pm

And you have been reading too much and thinking too little. An encyclopedia knows far more than you, but what good is its opinion about what isn't recorded within? ]:o)

Jeff H said:

You've been reading too much Stephen King... (One of the best opening lines in fiction..."The man in black fled across the desert, and the gunslinger followed.")

James S Saint said:

"“We may soon find that our whole universe isn’t even at the cosmic center.”""

Our entire universe is but a single drop of water that fell upon an ocean with a splash. And the entirety of that splash is merely a single grain of sand in an ocean of desert.

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Permalink Reply by Jeff H on November 19, 2009 at 9:43pm

an encyclopedia doesn't know anything James...

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Permalink Reply by James S Saint on November 19, 2009 at 10:03pm

Oh it "knows". It just hasn't a voice or a mind. You have a "voice". ]:o)

Jeff H said:

an encyclopedia doesn't know anything James...

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Permalink Reply by Jeff H on November 19, 2009 at 10:26pm

To know is to internalize.... but we're getting off the subject. The Stephen King reference was completely in keeping with your comment, if you've read the "Dark Tower" series, or even just "Gunslinger".

James S Saint said:

Oh it "knows". It just hasn't a voice or a mind. You have a "voice". ]:o)

Jeff H said:

an encyclopedia doesn't know anything James...

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Permalink Reply by James S Saint on November 19, 2009 at 10:41pm

Jeff H said:

To know is to internalize....

Ohhh, I see. You have never OPENED one. Hey listen, I'm tell'n ya its got great stuff "internally".

];o)

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Permalink Reply by Roman Kozlowski on November 22, 2009 at 8:20am

Our visible universe is coming to be more defined as just a small aspect seemingly attached to a membrane floating within a higher-dimensional space.

Physicists may soon be able to detect and verify the existence of reality's extra dimensions, which could extend over distances as large as a millimetre.

All the matter and forces we know of—with the sole exception of gravity—are stuck to a "wall" in the space of the extra dimensions. Electrons, protons, photons and all the other particles in the Standard Model cannot move in the extra dimensions; electric and magnetic field lines cannot spread into higher-dimensional space. The wall has only three dimensions, and so far as these particles are concerned, the universe might as well be three-dimensional. Only gravitational field lines can extend into the higher dimensional space, and only the particle that transmits gravity, the graviton, can travel freely into the extra dimensions. The presence of the extra dimensions can be felt only through gravity.

Particles such as electrons and photons are like tiny lengths of string that each have two end points that must be stuck to a D-brane, Gravitons, on the other hand, are tiny closed loops of string that can wander into all the dimensions because they have no end points anchoring them to a D-brane.

The membranes of other three-dimensional universes could lie parallel to our own, only a millimeter removed from us in the extra dimensions. Similarly, although all the particles in the Standard Model must stick to our own membrane universe, other particles beyond the Standard Model might propagate through the extra dimensions. Far from being empty, the extra dimensions could have a multitude of interesting structures.

Our entire three-dimensional universe is looking more likely at being just a thin membrane in the full space of dimensions.

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Permalink Reply by James S Saint on November 22, 2009 at 8:54am

Hahaha... and they blame Religious people of inventing superstitions to explain what they can't understand. (The IRONY)

..HAhaha.. ]:o))

Roman Kozlowski said:

Our visible universe is coming to be more defined as just a small aspect seemingly attached to a membrane floating within a higher-dimensional space.

Physicists may soon be able to detect and verify the existence of reality's extra dimensions, which could extend over distances as large as a millimetre.

All the matter and forces we know of—with the sole exception of gravity—are stuck to a "wall" in the space of the extra dimensions. Electrons, protons, photons and all the other particles in the Standard Model cannot move in the extra dimensions; electric and magnetic field lines cannot spread into higher-dimensional space. The wall has only three dimensions, and so far as these particles are concerned, the universe might as well be three-dimensional. Only gravitational field lines can extend into the higher dimensional space, and only the particle that transmits gravity, the graviton, can travel freely into the extra dimensions. The presence of the extra dimensions can be felt only through gravity.

Particles such as electrons and photons are like tiny lengths of string that each have two end points that must be stuck to a D-brane, Gravitons, on the other hand, are tiny closed loops of string that can wander into all the dimensions because they have no end points anchoring them to a D-brane.

The membranes of other three-dimensional universes could lie parallel to our own, only a millimeter removed from us in the extra dimensions. Similarly, although all the particles in the Standard Model must stick to our own membrane universe, other particles beyond the Standard Model might propagate through the extra dimensions. Far from being empty, the extra dimensions could have a multitude of interesting structures.

Our entire three-dimensional universe is looking more likely at being just a thin membrane in the full space of dimensions.

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Permalink Reply by James S Saint on November 26, 2009 at 4:43am

PALO ALTO, CA—Gathering for what members of the international science community are calling "potentially the most totally out-to-lunch freaky head trip since Einstein postulated that space and time were, like, curved and shit," a consortium of the world's top physicists descended upon Stanford University Monday to discuss some of the difficult questions facing the cutting edge of theoretical thinking.


Cal Tech physicist Dr. Jonathan Friedrich postulates a bunch of freaky shit that makes his colleagues' heads spin right the hell off.

Among the revolutionary ideas expected to be raised at the historic week-long summit is the possibility that, like, our whole friggin' universe might be just one big atom in, say, some super-duper huge thing out there somewhere, or something.

"Whoa, man," Dr. Jacob "The Boz" Bozeman of MIT told reporters. "The implications of this deceptively simple hypothesis are, like, completely blowing my mind. Like, we could all be nothing more than this little dot in the fingernail of some huge-ass giant dude. Or maybe a seed in the mustard of, like, some really big sandwich, or even a germ on the back of a flea that's, like, sitting on a hair on some giant dog's ass. Truly, it boggles the freakin' mind, man. It freaks me the fuck right out."

The universe-as-possible-giant-atom theory originated in May with a team of Cal Tech particle physicists, who developed the theory late one night while sitting around on a couch in the Physics Department's cyclotron and foosball facility, "just shooting the shit." The theory, which was reportedly conceived after the group became highly engrossed in ceiling-tile patterns for several minutes while waiting for a pizza to arrive, is said to be so advanced that only a few scientists in the world even have their heads together enough to really, you know, deal. Yet even among this elite group, many are said to be "seriously thrown for a loop" by its implications.

"I'm like, 'Whoa there, man, slow down,'" said Dr. Dieter Gerhardt, a low-temperature physicist at Cornell University. Pausing for a moment to collect himself, the renowned scientist then placed his hands on his forehead before extending them outward in a sweeping gesture and making a buzzing "space-noise" sound effect with his lips, non-verbally indicating the degree to which his mind was blown by the whole freaky deal.

Among other topics to be explored at the Stanford conference, according to Bozeman: the concept of parallel, or "alternate," Earths; the theory of multi-dimensional "superstrings" that fold backward and forward throughout the fabric of the universe; and "a whole bunch of other shit I totally can't even handle thinking about right now."

On Monday, the most high-profile conference attendee, Cambridge's Dr. Stephen Hawking, discussed his recent research exploring the possible existence of "sideways," or lateral, time, a concept most scientists in attendance described as "way out there."

"I don't want to fuck with anybody's head here," Hawking told the assembled scientists via his voice-simulation device, "but if time goes sideways as well as forward, there might be, like, other versions of this reality, where, say, the Roman Empire is still in charge and stuff."

"By the way," Hawking added, "ever think about what'd happen if you, say, went back in time and accidentally killed your own younger self? Man, that shit would be so fucked up."

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Permalink Reply by James S Saint on November 26, 2009 at 5:27am

Quantum physics

arensb@cvl.umd.edu (Andrew Arensburger)
(This just materialized on my desk one day. It's in my handwriting, so I must have written it, though I'll deny it if I'm indicted. -AA)

The topic for today is quantum physics. Quantum physics was developed in the 1930's, as a result of a bet between Albert Einstein and Niels Bohr, to see who could come up with the most ridiculous theory and still have it published. Most people agree that Bohr won hands down, although Einstein did very well in the swimsuit competition.

One of the most important researchers in quantum physics is Werner Heisenberg, a man with a wonderful sense of humor, who was always cracking one-liners, like "delta-p times delta-x is less than h!" Ha! ha! What a card! This is known as Heisenberg's Uncertainty Principle, which is closely related to Goedel's Incompleteness Theorem, which says that some things are true, but you can't prove them, like when my wife and I argue over whether it's her turn to take out the garbage or not.

What Heisenberg's Uncertainty Principle says is that if something is small enough, you can't say anything about it. Anyone with the I.Q. of baking powder immediately understood that this means that if you look at something so small that you can't even see it, like my dog, Oscar Wilde's, brain, then you obviously can't tell, say, what color it is.

But some people didn't get the joke, and decided to investigate this principle further. They would gather and sit around all day, drinking beer and performing "Gedankesexperimenten," or "Thank God we're theoretical physicists so we don't have to get our hands dirty with particle accelerators and other heavy machinery." The most famous of these is Schroedinger's Cat, where several physicists kidnap Erwin Schroedinger's cat Fluffy and lock it up in a box, along with a radioactive source such as Cheez Doodles. Then they walk around with concerned expressions on their faces, commenting about how they don't know what's going on inside the box. This goes on until the cleaning lady discovers the box, opens it and tells the physicists whether the cat is dead, or whether it has mutated into a man-eating flea the size of Norway.

The point of this experiment is to show that uncertainty at the quantum level can be detected in the macroscopic world and produce widespread anxiety and paranoia. It also explains why paper clips just lie there while you look at them, but as soon as you turn your back, they run away, giggling wildly, and transform themselves into coat hangers.

Another famous researcher is Richard Feynman, who invented Feynman diagrams, which are bunches of squiggly lines with greek letters next to them. The way they were discovered was, one day, Hans Bethe came in to Feynman's office to say that some of the guys down in particle research were having a jam session down by the cyclotron, and would Richard like to come over and bring his bongos? Feynman was out, at the time, cracking a safe or something, so Bethe tried to leave him a note. On the desk, he found one of Feynman's daughter's kindergarten drawings. Bethe couldn't make head or tail of it, and figured that if even he couldn't understand it, then it must be something Terribly Clever, and promptly called it a Feynman diagram.

This was a major scientific breakthrough, and ever since, proud parents have been hanging their children's Feynman diagrams on refrigerators with little muon-shaped magnets, confident that their Little Darlings are developing important scientific theories every day, because they are, after all, Gifted Children.

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Permalink Reply by Roman Kozlowski on November 26, 2009 at 5:29pm

James S Saint

You're either very brave in your denunciation of the latest science or a complete tit for saying so.

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Permalink Reply by doone on November 26, 2009 at 6:04pm

I would be proud if my child could draw anything like this:

Feynman Diagrams

Richard Feynman was the physicist who developed the method still used today to calculate rates for electromagnetic and weak interaction particle processes. The diagrams he introduced provide a convenient shorthand for the calculations. They are a code physicists use to talk to one another about their calculations.

In Feynman diagrams (time ordered form):

• Left-to-right in the diagram represents time; a process begins on the left and ends on the right.
• Every line in the diagram represents a particle; the three types of particles in the simplest theory (QED) are:

Image	Description	Particle Represented
	straight line, arrow to the right	electron
	straight line, arrow to the left	positron
	wavy line	photon

• Up and down (vertical) displacement in a diagram indicates particle motion, but no attempt is made to show direction or speed, except schematically.
• Any vertex (point where three lines meet) represents an electromagnetic interaction; possible vertices are (and notice that all six of these processes are just different orientations of the same three elements):

	An electron emits a photon
	An electron absorbs a photon
	A positron emits a photon
	A positron absorbs a photon
	A photon produces an electron and a positron (an electron-positron pair)
	An electron and a positron meet and annihilate (disappear), producing a photon

• Any diagram which can be built using these parts is a possible process provided:
  1. Conservation of energy and momentum is required at every vertex
  2. Lines entering or leaving the diagram represent real particles and must have E²=p²c²+m²c⁴.
  3. Lines in intermediate stages in the diagram represent "virtual particles," which do not need to have the right relationship between E, p, and m, but which can never be observed if they do not!

  The first thing to realize is that no single vertex diagram represents a possible process - no matter how you try, you cannot satisfy rules (1) and (2) above at the same time for such a process.

The simplest process we can consider is a two particle collision or "scattering" event. Let us start and end the process with one electron and one positron-- only their momenta and energies change in the process:

Feynman tells us to draw all possible diagrams. First, lets add one intermediate photon line. We find three time-ordered diagrams:

(a)	(b)	(c)
The first two figures (a and b) are just different orientations (time-orderings) of the same event.  We use the figure (d)  below as a shortcut to show both orientations.		This third diagram (c) is really quite a different process -- it is an intermediate  stage with only  a photon (a virtual photon) present.
(d)
Notice that this diagram does not have time orderings, just a start and stop.

We can also draw more complicated diagrams with more photons, for example:

or

In fact, we could have any number of photons!

What makes the diagrams useful is that each diagram has a definite complex number quantity -- called an amplitude -- related to it by a set of rules (the Feynman rules). One part of these rules is that there is a multiplication factor of   for each photon, so the amplitudes for diagrams with many photons are small, compared to those with only one. The quantity "e" here is the electromagnetic coupling or electric charge.

Technically, the Feynman rules give the rate as a power series expansion in the coupling parameter. The technique is only useful when this parameter is small, that is, for electromagnetic or weak interactions but not for stronginteractions except at very high energies.

Calculations in QED keeping up to four photons have been made for certain quantities. They give a result that matches experimental data up to the twelfth decimal place!

Real and Virtual Particles

Because Feynman diagrams represent terms in a quantum calculation, the intermediate stages in any diagram cannot be observed. Physicists call the particles that appear in intermediate, unobservable, stages of a process "virtual particles". Only the initial and final particles in the diagram represent observable objects, and these are called "real particles."

Feynman Rules

The Feynman Rules for a theory are very simple, but lead to increasingly complicated mathematical expressions as increasingly complicated diagrams are constructed.

The rules for any process are:

• Draw all possible diagrams (up to some number of photons, depending on the accuracy desired). Different time-orderings of a given process are represented by the same diagram.
• Given the initial momentum and energy, define how momentum and energy flow for each line in the diagram. Where each diagram has a closed loop, there is an arbitrary momentum and energy flow around the loop and we must integrate over all possible choices for these quantities. Each intermediate line in the diagram contributes a factor to the amplitude of  1/(E²-p²c²-m²c⁴) where m is the appropriate mass for the particle type represented by the line. Note that this says that the more "virtual" the particle represented by a line is, the smaller the contribution of the diagram.
• Add the amplitude factors from all possible diagrams to get the total amplitude for the process.

The expected rate for the process can then be calculated -- it is proportional to the absolute value of the total amplitude squared. [Note that this is not the same as the sum of the squares of the absolute values of the individual amplitudes.] For more information on this topic, take a look at the discussion of quantum interference.

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