"boutshka" <carollombard@gmail.com> wrote in message
news:1160377445.918041.308390@i42g2000cwa.googlegr oups.com...
>
> gravity wrote:
>> "boutshka" <carollombard@gmail.com> wrote in message
>> news:1160297878.832051.314340@b28g2000cwb.googlegr oups.com...
>> >
>> > gravity wrote:
>> >> what are you up to?
>> >>
>> >> Gravity
>> >
>> > watching TV. 
>> >
>>
>> i have 9 beers (smile) so i am going to watch a DVD and then get some
>> sleep.
>> i am going to start with the rest of the Fast and Furious, not usually my
>> cup of tea, but i love high power cars that are sorta street-legal.
>>
>> they should make a car movie and mix string theory into it, and i'd love
>> it.
>> or maybe Nova already did that.
>
> Hmm..wasn't that "Back to the Future" I, II, III, etc?
>
> Gravity hasn't string theory now been rejected by mainstream
> physicists, with interest in it only by a spare fringe?
no, it's still the hottest thing going.
current situation:
physics collapsed on itself. theory got so far ahead of experiment that no
one knew what to do next. we (humans) had two good theories: general
relativity and quantum field theory. there are two goals beyond those
theories. one is to unify ALL the forces, basically take the Standard Model
(electromagnetism, nuclear forces) and blend them with gravity. this is the
so called theory of quantum gravity. no one can figure out how the hell to
do quantum gravity in 4 dimensions (basically 3 spatial / space and 1
temporal / time). there a ton of other problems like asymptotic freedom and
background dependence. these are kind of hard to explain, but they are very
real problems. i really think part of this trouble is due to space and time
being really wierd, and i don't think we have a full grip on it yet.
string theory is as far out there as it gets. it is the most convolted and
elaborate construction in physics ever. it takes a good 5 to 10 years to
even work on basic string theory, unless you are a genius. there is only
one string theory book that is even remotely easy to read, and even it
builds on relativity theory and quantum mechanics.
ok, there is more to the game than just quantum gravity. people want a
theory of everything. this is where string theory comes in. it happens on
a very small scale, many orders of magnitude smaller than an electron. the
problem with this is that no particle accelerator in the world can verify
much of the theory.
so enter the age of postmodern physics. it's no longer science anymore,
it's something more akin to mathematics or art.
and it's no longer "elegant" either. it's huge, bloated, and fucked up.
history:
~ 1970 dual resonance model (birth)
1984 first superstring revolution
~ 1995 second superstring revolution
"oh my god, it's a string, i must be the only hippie in the world who knows
this, but those guys keep rejecting my paper, so i'm gonna get fucked up on
Heineken instead".
string theory was born from a total failure. when QCD came out, everyone
forgot about bootstrap theory. but maybe the old approach is actually valid
after all. QCD basically explains the strong force e.g. gluons being the
gauge boson exchanged by quarks.
that beer line sounds like a joke, but that was how string theory was born.
new age:
in recent years, people like Peter Woit and Lee Smolin have questioned
string theory. this skepticism and book reviews are making their way into
newspapers worldwide. eventually politicians are going to ask for more
accountability for government funding.
a big problem:
we (humans) need to work on a competing theory. but which one? Penrose and
others worked on twistors and other stuff, but that was not going well.
Smolin worked on loop quantum gravity, but hardly anyone is teaching that
these days.
future:
Smolin says there are two types of physicists: seers and craftsmen. string
theory is done by craftsmen. they take an idea and build it up to it's
absolute breaking point, much like modernism in the arts. seers, on the
other hand, come up with new directions.
Smolin claims there are too many craftsmen and too few seers. the next
breakthrough may very well come from an amateur or professional, whose day
job is not particle physics.
duality:
loop quantum gravity and string theory are the same thing. just we are
viewing things from a different perspective. duality is very hot in physics
these days.
conclusion:
string theory is probably wrong, but it is creating new tools and advancing
mathematics. in that sense, the ends justify the means. but the taxpayers
are fooled into thinking that particle physics has made significant progress
in the last 30 years.
Gravity
p.s. i'm not a physicist.
hey Carol 
Linear Mode
