http://sifter.org/~aglisi/JournalG/20071114.html

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Tom Galvin wrote:
> http://sifter.org/~aglisi/JournalG/20071114.html

My main experience with this has been the feeling of "boy, I wish I knew 
enough physics to judge this paper's merits for myself".  It is sort of 
interesting to watch though, I have to admit.

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Le 17.11.2007 02:55, Kevin Wampler nous fit lire :
> Tom Galvin wrote:
>> http://sifter.org/~aglisi/JournalG/20071114.html
> 
> My main experience with this has been the feeling of "boy, I wish I knew
> enough physics to judge this paper's merits for myself".  It is sort of
> interesting to watch though, I have to admit.

Interestingly enough, 8 dimensions spaces does have a
cross-product... sort of.

-- 
The superior man understands what is right;
the inferior man understands what will sell.
-- Confucius

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One thing I have never really understood is why they are so vehemently
trying to find a "unified theory of everything".

  We have models which describe how things work at quantum scale, and we
have models which describe how things work at macroscale (including high
speeds and high masses). Neither model describes well the other, but why
is this such a big deal? Why can't we have two (or more) models at the
same time?

  This may be a far-fetched analogy, but we have theories and models of
how car engines should be built, and we have theories and models of how
skyscrapers should be built. Neither model can be used to describe the
other situation, but so what? That doesn't cause any problems. If you
are building a car engine, use the car engine model. If you are building
a skyscraper, use the skyscraper model. Where's the problem? Why would
we even need a "unified model" which describes both car engines and
skyscrapers at the same time? There's no need, and it would only completely
unnecessarily complicate things.

  Is it just a question of coolness, or is there some practical issue
in play here?

-- 
                                                          - Warp

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Following links from there, I found this an interesting read:

http://cosmicvariance.com/2007/11/01/dark-matter-still-existing/

-- 
                                                          - Warp

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Warp nous apporta ses lumieres en ce 2007/11/17 06:31:
>   Following links from there, I found this an interesting read:
> 
> http://cosmicvariance.com/2007/11/01/dark-matter-still-existing/
> 
The defenition of "dark matter":
Any matter that we can't directly observe.
What can it be? Diffuse gases, dust clouds, "sand" clouds, "gravel" cloud, 
cluster of rogue planets, failed and dead stars, brown stars, IR stars. The list 
goes from the easiest to detect to the hardest.

-- 
Alain
-------------------------------------------------
When the bosses talk about improving productivity, they are never talking about 
themselves.

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Warp wrote:
>   One thing I have never really understood is why they are so vehemently
> trying to find a "unified theory of everything".

	Probably different people have different answers/reasons.

	Theoretical physicists are rarely concerned with what is practical. An 
underlying assumption among many is that there *is* a universal theory, 
and since there is, the models they currently have don't describe the 
"truth" (although they may describe all of it).

	Also, if they find such a theory, they may be able to predict phenomena 
not seen otherwise. His paper predicts a number of new particles, for 
example. Perhaps no one would have observed them (assuming its true) in 
experiments had they not been guided on where to look by such a theory.

	And, I assume, there are still phenomena that current physics doesn't 
explain adequately. So they assume a universal theory will do a better job.

	I remember as an undergrad arguing with my engineering professors on a 
very similar concept. In circuits, we learn certain equations (Ohm's 
Law, oscillating systems, etc). However, most professors don't point out 
the analogy between those systems and mechanical ones (the equations are 
of the exact same mathematical form).  Later when the students studied 
mechanics courses, almost no one saw the relationship and they 
re-learned all those properties. And I'm sure they'd do it again for any 
other oscillating system they'd study.

	When I took basic physics courses, they did things differently. They 
first studied the mathematical properties of that class of equations 
(perhaps motivated by a real world example). Once all the math was taken 
care of, they went through one physical system after another, showed 
that their governing equations had the same form, and then obtained the 
basic physical properties of all those systems in one fell swoop.

	Now they sure could have gone the route that the engineers did. But I 
think everyone would agree they "understood" the systems better once 
they understood the unifying principles (the properties of the 
mathematical equations in abstract).

-- 
Why do the Alphabet song and Twinkle, Twinkle Little Star have the same 
tune?


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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Warp wrote:
>   One thing I have never really understood is why they are so vehemently
> trying to find a "unified theory of everything".
> 
>   We have models which describe how things work at quantum scale, and we
> have models which describe how things work at macroscale (including high
> speeds and high masses). Neither model describes well the other, but why
> is this such a big deal? Why can't we have two (or more) models at the
> same time?
Because there is a medium scale and mixed scales?
For example one of the things we cannot describe at the moment (IIRC) is 
the behaviour of one electron in a big gravitational field e.g. close to 
a black hole. You need both quantum mechanics and relativity for that.
One of the jokes of one of my quantum teachers was that you can see the
progress of science in what systems of particles you can solve. In 
newtonian physics the three body system is unsolvable. Then with general 
relativity the 2 body problem becomes analytically unsolvable. With the 
addition of quantum mechanics the behaviour of a single particle is 
beyond reach (see above) and nowadays we cannot even solve the vacuum 
anymore.

> 
>   This may be a far-fetched analogy, but we have theories and models of
> how car engines should be built, and we have theories and models of how
> skyscrapers should be built. Neither model can be used to describe the
> other situation, but so what? That doesn't cause any problems. If you
> are building a car engine, use the car engine model. If you are building
> a skyscraper, use the skyscraper model. Where's the problem? Why would
> we even need a "unified model" which describes both car engines and
> skyscrapers at the same time? There's no need, and it would only completely
> unnecessarily complicate things.
Unless you want to build a movable skyscraper. Trust me, someone will 
one day.

> 
>   Is it just a question of coolness, or is there some practical issue
> in play here?
> 
Whether there is a practical advantage will only show after unification. 
But of course the main problem is that it is bloody annoying at parties.

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Warp wrote:
>   One thing I have never really understood is why they are so vehemently
> trying to find a "unified theory of everything".

As Mueen stated, it's probably to predict what currently can't be 
predicted. He was talking about the properties of particles which still 
have yet to be discovered, but the implications could reach farther. In 
fact, if we could determine *all* the factors present during the Big 
Bang, we will be one step closer to predicting future events. Of course, 
to accurately model the Universe we must use other parallel universes 
for computational purposes. I don't think we will ever reach such an 
advanced state (assuming such a thing is possible). We will most likely 
wipe ourselves out long before making such progress.

>   This may be a far-fetched analogy, but we have theories and models of
> how car engines should be built, and we have theories and models of how
> skyscrapers should be built. Neither model can be used to describe the
> other situation, but so what? That doesn't cause any problems. If you
> are building a car engine, use the car engine model. If you are building
> a skyscraper, use the skyscraper model. Where's the problem? Why would
> we even need a "unified model" which describes both car engines and
> skyscrapers at the same time? There's no need, and it would only completely
> unnecessarily complicate things.

In light of our current state of knowledge regarding basic physics, your 
assumption makes sense. But what if we do find a unified theory of all 
existence which makes us reconsider our severely limited knowledge of 
low-level physics? We might find that the approach to engineering a 
skyscraper and our approach to engineering a car engine becomes, er, 
more unified :)

>   Is it just a question of coolness, or is there some practical issue
> in play here?
> 
There are always practical issues regarding the advancement of knowledge.

Sam

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Warp wrote:
>   Is it just a question of coolness, or is there some practical issue
> in play here?

I think it's more a combination of two things:

One - that the two theories are incompatible. Relativity requires 
continuous functions. Quantum disallows continuous functions. If space 
(including gravity etc) is smoothly continuous at the smallest levels, 
quantum theory would give the wrong answer. If space were discontinuous 
at the smallest levels, relativity would give the wrong answers, even at 
the big sizes. So, basically, people *know* that one of them is "wrong", 
even though both are giving the right answers to the precision with 
which they can be measured. And QED at least has been measured and 
matches predictions to something like 15 decimal places, which is an 
incredible precision.

Two - figuring out the combination might lead to all kinds of new 
discoveries. Just as an example, in 1890 or so, people thought they knew 
all about how light worked, and so on, except for one or two little 
anomalies, like black-body radiation and the photoelectric effect at low 
light levels. It took a whole new shift to quantum calculations to be 
able to understand those effects. That resulted in lasers, 
semiconductors, understanding genetics at the individual protein level, 
and so on.

If you can unify the operations of gravity and quantum interactions, you 
might be able to make electrogravitics, anti-gravity, gravity-powered 
light bulbs, stuff like that. Who knows? If you could get quantum 
miracles(*) to work reliably over space-like distances, you could get 
teleportation, time travel, stuff like that.

Plus, it might explain *why* quantum stuff is random, and whether 
there's any underlying unmeasurable rules, and so on, even if you can't 
manipulate it.


(*) AKA very low probability quantum teleportation events, like in 
tunnel diodes only long distances.
-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Darren New <dne### [at] sanrrcom> wrote:
> gravity-powered light bulbs

  That sounds like a perpetual motion machine. Unlikely. :P

-- 
                                                          - Warp

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> gravity-powered light bulbs
> 
>   That sounds like a perpetual motion machine. Unlikely. :P

I guess it depends on what causes gravity. Maybe gravity isn't constant. 
I read one fictional story where the physicists discovered that gravity 
is caused by the spontaneous destruction of mass and created by the 
spontaneous creation of mass.  So places where there was lots of mass 
had more gravity, because it was more likely there would be a subatomic 
particle disappearing, and why the rest of the universe had a nice 
sparse sprinkling of random hydrogen atoms. :-)

Or maybe gravity-powered light bulbs would just be a more direct way 
than, say, tidal bore generators; a gravity-powered bulb might make the 
earth lighter or orbit slower or something.  Or maybe it would only work 
if the bulb was moving up or down. :-)

Gravity is pretty weak anyway. It takes the whole earth to hold you 
down, and just a little layer of electrons to hold you up.  I read if 
you took all the electrons off a 1cm cube of aluminum, and held them 1 
meter away, the force between the two would match the weight of a cube 
of iron 76 miles on a side. Vast difference in power, which is one of 
the reasons it's so hard to do quantum gravity experiments.

Plus, of course, maybe conservation of energy isn't true. That's the 
sort of thing a ToE has the chance to support or disprove. :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> gravity-powered light bulbs
> 
>   That sounds like a perpetual motion machine. Unlikely. :P

	Unless our Theory of Everything provides exceptions to the 2nd Law of
Thermodynamics based on certain rare circumstances.

	Those Laws are just a result of our observations, and can change. I'm
sure in the early 19th century, people would have scoffed at particles
with mass diffracting.

-- 
Why do the Alphabet song and Twinkle, Twinkle Little Star have the same
tune?


                    /\  /\               /\  /
                   /  \/  \ u e e n     /  \/  a w a z
                       >>>>>>mue### [at] nawazorg<<<<<<
                                   anl

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Mueen Nawaz wrote:
> 	Unless our Theory of Everything provides exceptions to the 2nd Law of
> Thermodynamics based on certain rare circumstances.

I'm told by other physicists that the zero-point energy might actually 
be tappable, or at least that there's no entropic reason it couldn't be.

-- 
   Darren New / San Diego, CA, USA (PST)
     Remember the good old days, when we
     used to complain about cryptography
     being export-restricted?

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Darren New <dne### [at] sanrrcom> wrote:
> I'm told by other physicists that the zero-point energy might actually 
> be tappable, or at least that there's no entropic reason it couldn't be.

  Does that mean we might get a real-life gravity gun (aka. zero-point
energy field manipulator) someday?-)

-- 
                                                          - Warp

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andrel wrote:
> Whether there is a practical advantage will only show after unification. 
> But of course the main problem is that it is bloody annoying at parties.

Not as annoying as having all your underwear teleported two feet away 
when somebody fires up the Bambleweeny 57 sub-meson brain and plugs in 
the atomic vector plotter. Oh, wait, physicists don't get invited to 
those sorts of parties...

:)

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And lo on Sat, 17 Nov 2007 10:44:57 -0000, Warp <war### [at] tagpovrayorg> did  
spake, saying:

>   One thing I have never really understood is why they are so vehemently
> trying to find a "unified theory of everything".
>
>   We have models which describe how things work at quantum scale, and we
> have models which describe how things work at macroscale (including high
> speeds and high masses). Neither model describes well the other, but why
> is this such a big deal? Why can't we have two (or more) models at the
> same time?

Darren's is the best explanation, both theories start with different  
assumptions about the same thing; yet both are accurate. Problem two is  
when you get a theory A object behaving like a theory B object, because of  
problem 1 you can't mix-and-match the equations and all you get out of  
them is infinities (unless you're fine with physical infinities).

>   This may be a far-fetched analogy, but we have theories and models of
> how car engines should be built, and we have theories and models of how
> skyscrapers should be built. Neither model can be used to describe the
> other situation, but so what? That doesn't cause any problems. If you
> are building a car engine, use the car engine model. If you are building
> a skyscraper, use the skyscraper model. Where's the problem? Why would
> we even need a "unified model" which describes both car engines and
> skyscrapers at the same time? There's no need, and it would only  
> completely
> unnecessarily complicate things.

Except both skyscrapers and car engines use the same material science and  
physics and start with the same assumptions, they're just applied in  
different ways. A car-engine designer can use the same science to build a  
skyscraper, he doesn't need to switch equations, just take some extra  
things into consideration.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Bill Pragnell wrote:
> andrel wrote:
>> Whether there is a practical advantage will only show after 
>> unification. But of course the main problem is that it is bloody 
>> annoying at parties.
> 
> Not as annoying as having all your underwear teleported two feet away 
> when somebody fires up the Bambleweeny 57 sub-meson brain and plugs in 
> the atomic vector plotter. Oh, wait, physicists don't get invited to 
> those sorts of parties...
> 
> :)

1) I am indeed never invited
2) I don't drink tea
3) I am not a woman

not necessarily in that order.

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> I'm told by other physicists that the zero-point energy might actually 
>> be tappable, or at least that there's no entropic reason it couldn't be.
> 
>   Does that mean we might get a real-life gravity gun (aka. zero-point
> energy field manipulator) someday?-)

Well, the "zero-point energy" is (amongst other things) the remaining 
jiggle in atoms even at absolute-zero. It *has* to be there, because 
without it, you'd know both the momentum and position precisely. It's 
the "heat" that keeps liquid helium from freezing. It's the energy that 
comes from spontaneous pair creation and destruction. It's the driver of 
the Casimir effect.

Whether it has anything to do with gravity is unknown yet. We'll know, 
when the ToE is found that actually predicts accurately.

But this was more a discussion of whether essentially could you build a 
battery that never goes flat.

-- 
   Darren New / San Diego, CA, USA (PST)
     It's not feature creep if you put it
     at the end and adjust the release date.

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Darren New wrote:
> I'm told by other physicists that the zero-point energy might actually
> be tappable, or at least that there's no entropic reason it couldn't be.

	Interesting. Have no idea - my statistical mechanics is quite weak, and
I never learned much of it anyway.

-- 
ASCII stupid question... get a stupid ANSI!


                    /\  /\               /\  /
                   /  \/  \ u e e n     /  \/  a w a z
                       >>>>>>mue### [at] nawazorg<<<<<<
                                   anl

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Darren New <dne### [at] sanrrcom> wrote:
> Well, the "zero-point energy" is (amongst other things) the remaining 
> jiggle in atoms even at absolute-zero.

  Isn't that kind of contradictory with the very definition of absolute
zero temperature? By definition if there's movement it's not absolute zero.

> It *has* to be there, because 
> without it, you'd know both the momentum and position precisely.

  Did Heisenberg really state that the principle applies at all possible
temperatures, including absolute zero? Does it break some kind of universal
law (like conservation of energy or conservation of momentum) if at absolute
zero the uncertainty principle does not apply?

-- 
                                                          - Warp

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Warp nous apporta ses lumieres en ce 2007/11/20 04:38:
> Darren New <dne### [at] sanrrcom> wrote:
>> Well, the "zero-point energy" is (amongst other things) the remaining 
>> jiggle in atoms even at absolute-zero.
> 
>   Isn't that kind of contradictory with the very definition of absolute
> zero temperature? By definition if there's movement it's not absolute zero.
> 
>> It *has* to be there, because 
>> without it, you'd know both the momentum and position precisely.
> 
>   Did Heisenberg really state that the principle applies at all possible
> temperatures, including absolute zero? Does it break some kind of universal
> law (like conservation of energy or conservation of momentum) if at absolute
> zero the uncertainty principle does not apply?
> 
ZPE is also the total energy of every photon that fits within any given finite 
space, limited by it's wave length. In any volume you will find at least one 
photon for every wave length that is less or equal than the dimentions of that 
volume.
Now, how much energy does a single gamma ray photon cary? And now, how many 
times it's wave length fits within an hydrogen atom?

-- 
Alain
-------------------------------------------------
I used to have an open mind but my brains kept falling out.

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Well, the "zero-point energy" is (amongst other things) the remaining 
>> jiggle in atoms even at absolute-zero.
> 
>   Isn't that kind of contradictory with the very definition of absolute
> zero temperature? By definition if there's movement it's not absolute zero.

	From Wikipedia:

"Absolute zero is the point at which particles have a minimum energy,
determined by quantum mechanical effects, which is called the zero-point
energy."

	I guess one can define absolute zero your way as well - but then it
becomes physically unattainable.

>   Did Heisenberg really state that the principle applies at all possible
> temperatures, including absolute zero? Does it break some kind of universal
> law (like conservation of energy or conservation of momentum) if at absolute
> zero the uncertainty principle does not apply?

	Don't know if Heisenberg stated it, but I think physicists believe it
does. What makes those universal laws and not this?

-- 
ASCII stupid question... get a stupid ANSI!


                    /\  /\               /\  /
                   /  \/  \ u e e n     /  \/  a w a z
                       >>>>>>mue### [at] nawazorg<<<<<<
                                   anl

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Well, the "zero-point energy" is (amongst other things) the remaining 
>> jiggle in atoms even at absolute-zero.
> 
>   Isn't that kind of contradictory with the very definition of absolute
> zero temperature? By definition if there's movement it's not absolute zero.

Only in layman's terms. Either you can't ever get to absolute zero, or 
there is a theoretical range where the energy is negative (said range 
also inaccessible in some sense).

But at this point you're pushing my knowlege of the subject.

>   Did Heisenberg really state that the principle applies at all possible
> temperatures, including absolute zero? 

I don't know. But look up "Bose-Einstein condensate", where you take one 
atom and make it about 10 feet across by getting it close enough to 
absolute zero.

 > Does it break some kind of universal
> law (like conservation of energy or conservation of momentum) if at absolute
> zero the uncertainty principle does not apply?

Honestly, I don't know, but I wouldn't be surprised. I understand many 
of the conservation laws come from quantum measurements.

-- 
   Darren New / San Diego, CA, USA (PST)
     It's not feature creep if you put it
     at the end and adjust the release date.

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And lo on Tue, 20 Nov 2007 09:38:17 -0000, Warp <war### [at] tagpovrayorg> did  
spake, saying:

> Darren New <dne### [at] sanrrcom> wrote:
>> Well, the "zero-point energy" is (amongst other things) the remaining
>> jiggle in atoms even at absolute-zero.
>
>   Isn't that kind of contradictory with the very definition of absolute
> zero temperature? By definition if there's movement it's not absolute  
> zero.

To tie this back to your original query the concept of absolute zero  
resided in 'classical' science whereas ZPE belongs in quantum science.  
Once again we have two otherwise accurate methods disagreeing.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Phil Cook wrote:
> And lo on Tue, 20 Nov 2007 09:38:17 -0000, Warp <war### [at] tagpovrayorg> 
> did spake, saying:
>>   Isn't that kind of contradictory with the very definition of absolute
>> zero temperature? By definition if there's movement it's not absolute 
>> zero.
> To tie this back to your original query the concept of absolute zero 
> resided in 'classical' science whereas ZPE belongs in quantum science. 
> Once again we have two otherwise accurate methods disagreeing.

Not as such; if absolute zero is defined as the temperature at which all 
molecular motion ceases, and ZPE is an accurate description of what 
exists, then one simply says "absolute zero is an unattainable property 
due to the phenomenon of zero-point energy".

-- 
Tim Cook
http://home.bellsouth.net/p/PWP-empyrean

-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GFA dpu- s: a?-- C++(++++) U P? L E--- W++(+++)>$
N++ o? K- w(+) O? M-(--) V? PS+(+++) PE(--) Y(--)
PGP-(--) t* 5++>+++++ X+ R* tv+ b++(+++) DI
D++(---) G(++) e*>++ h+ !r--- !y--
------END GEEK CODE BLOCK------

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And lo on Wed, 21 Nov 2007 13:10:11 -0000, Tim Cook  
<z99### [at] bellsouthnet> did spake, saying:

> Phil Cook wrote:
>> And lo on Tue, 20 Nov 2007 09:38:17 -0000, Warp <war### [at] tagpovrayorg>  
>> did spake, saying:
>>>   Isn't that kind of contradictory with the very definition of absolute
>>> zero temperature? By definition if there's movement it's not absolute  
>>> zero.
>> To tie this back to your original query the concept of absolute zero  
>> resided in 'classical' science whereas ZPE belongs in quantum science.  
>> Once again we have two otherwise accurate methods disagreeing.
>
> Not as such; if absolute zero is defined as the temperature at which all  
> molecular motion ceases, and ZPE is an accurate description of what  
> exists, then one simply says "absolute zero is an unattainable property  
> due to the phenomenon of zero-point energy".

But we know absolute zero is unattainable in non-isolated systems due to  
the implications of the second law of thermodynamics without the  
requirements of ZPE, however ZPE seems to set a limit on isolated systems  
too. IOW from a classical viewpoint there appears to be no reason why 0K  
for an isolated system cannot be achieved, but there is in quantum theory.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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Tim Cook wrote:
> Not as such; if absolute zero is defined as the temperature at which all 
> molecular motion ceases, 

Actually, the original "absolute zero" was a calculation. If you take a 
litre of gas at 300K and chill it to 150K, it has about half the volume. 
If you chill it to 75K, it has a quarter the volume. Absolute zero was 
postulated as the temperature at which it would have no volume, 
originally, and was recognized as probably not how things would really 
work if you could manage to get things that cold. :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     It's not feature creep if you put it
     at the end and adjust the release date.

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