Mathematical way of testing this statement?

[marcus]

Just occurred to me I should probably edit out my earlier post
because it was lacking in reserve and dignity. In fact I was
yakking like a moron. However I did enjoy this link, which I think
I got from you, to an item in "physics news update", about gravity.

http://www.aip.org/enews/physnews/1999/split/pnu454-1.htm

I've been going over past physics news update (pnu) things today
and like that website very much. The science writers they have there, doing the short summary reports, are serious and don't waste words just being "journalistic". I see you have pointed to several pnu newsitems. Thanks for the lead.

Marcus

 

[wolram]

What is the simplest evidence that there are more than 4 dimensions?
There is none. All of the 'evidence' is of the theoretical kind, but none of it has been put to the test because...we don't know how! All we know is that our space-time is 4 dimensional to about a few parts per hundred billion based on how well gravity follows 4-D general relativity inside our solar system.

i found this quote by a respected scientist
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[marcus]

Originally posted by wolram
What is the simplest evidence that there are more than 4 dimensions?
There is none. All of the 'evidence' is of the theoretical kind, but none of it has been put to the test because...we don't know how! All we know is that our space-time is 4 dimensional to about a few parts per hundred billion based on how well gravity follows 4-D general relativity inside our solar system.

i found this quote by a respected scientist

That is an interesting quote. I'm curious to know who said it, as I would look them up on the web and see what other things they said. Sometimes I am amazed at how much the internet makes science better---that is, more fun and accessible to a wider audience. (Because one of the most fundamental things science ought to be is fun and accessible to a wider audience, if it is that, then it is better science.) If I hear of a person or an idea then it is highly probable that I can find out more about that idea within 3 minutes, and so on.

You have turned up some interesting stuff on the web, you know what I mean. Its great. And every serious "science watcher" has, I believe, a perfect right to express their opinion. You don't have to play football in order to know the teams and who's winning, just like you don't have to be a horse in order to know the odds.
In fact it probably helps if you are NOT a horse. Outsiders make good watchers. I am talking too much as usual. Well, my wife just came in and told me what I have to do for the next hour or so.
Be back later,

m

 

[wolram]

quote is by Dr Sten Odenwald, I am sorry i don't have a link, i downloaded this in the late nineties, i know i should keep urls

 

[wolram]

this is the horses mouth
http://cgpg.gravity.psu.edu/research/index.shtml
click on links
i hope you find this interesting

 

[marcus]

Originally posted by wolram
this is the horses mouth
http://cgpg.gravity.psu.edu/research/index.shtml
click on links
i hope you find this interesting

this is a great link. thanks!


I had been to the site before to look up the schedule of talks at
a conference but had never tried "links"

they have books and papers there that I don't know of
being available elsewhere online

the site will keep me busy for a while, am reading
Ashtekar's paper ("Quantum mechanics of geometry" 1998)
now, which I don't remember seeing even a reference to
anywhere else.

 

[jeff]

Thiemann in this very recent paper includes a useful assessment of the LQG program which I think is worth a look:

http://xxx.lanl.gov/abs/gr-qc/0305080

Perhaps I'll post a summary.

 

[wolram]

do you understand all of that JEFF, in my unqualified opinion that is a mathmatical soup deep enough to drown most people
as i understand we should be getting results from satalite surveys soon until then I am going to keep from drowning
in the mean time if you have information that a non post grad could understand i would love to see it

 

[jeff]

Originally posted by wolram
do you understand all of that JEFF

Yep.

 

[wolram]

analy retentative or what? yep is what my dog exclaimes when i accidently tread on his tail, that sort of reply gets you no points
if you know somthing its not big or clever to keep it to yourself
i thought you were going to be helpful shows how stupid i am, good luck on your ego trip and watch out for icebergs

 

[jeff]

Originally posted by wolram
analy retentative or what? yep is what my dog exclaimes when i accidently tread on his tail, that sort of reply gets you no points
if you know somthing its not big or clever to keep it to yourself
i thought you were going to be helpful shows how stupid i am, good luck on your ego trip and watch out for icebergs

Some people like starting threads to teach or to create a place where people can learn on a cooperative basis and that's fine. I prefer answering specific physics questions and you haven't asked one. But you're definitely the first to misinterpret one of my "yeps" as "fu*k you". Where did that come from? I didn't deserve that and your way out of line. In fact your post violates rule 5 of the site posting guidelines as spelled out by Janus as follows:

Keep arguments confined to the Ideas and subject at hand, and not on personalities. I also frown on “baiting”; trying to prod the other guy into starting an argument or to delve into personalities.

You know, I have this sort of problem with marcus all the time. The interesting thing is how carefully he's avoided asking me specific physics questions or answering any of mine with anything but personal insults. You owe me an apology and if you can't see that then your the jerk, not me.

 

[wolram]

ok jeff i see your point i did step out of line i do apologise,
but you must see it from my side as well, i have been trying to
learn what gravity is now for over a year spending hours on the net
reading books etc, only to find out that the theories are full of holes.
it may ruffle your feathers if i say string theory isn't in "vogue"
it may do the same to other people if i say QLT is in "tatters"
its an uqualified opinion but its the truth as i see it.
im willing to listen and learn from anyone, but i don't want to wast my time in the process..

 

[jeff]

Originally posted by wolram
ok jeff i see your point i did step out of line i do apologise

I appreciate your apology very much, thankyou. I think we can forget about it.

Originally posted by wolram
it may ruffle your feathers if i say string theory isn't in "vogue"

People here are much more interested in LQG than strings, which is fine. The most important thing to me - and I've posted this a number of times - is that LQG provides an interesting opportunity to learn some neat physics and that's exactly what's happening. In any event, even if LQG is wrong - as most high energy theorists believe - there's evidence that it's telling us something about QG that we don't yet understand.

If it was my intention to shove strings down everyone's throats here I would've started my own threads on the subject. So unless someone explicitly says something about strings, I tend not to mention it. Besides, unlike LQG, strings can't be understood by reading two or three judiciously chosen papers. Strings also require a solid foundation in QFT, and a lot more math, neither of which people here have. Anyway, the scope and nature of LQG and strings are very different and nobody really needs to choose between them.

The most important omission in the threads about LQG are discussions about it's central unresolved issue of how to solve the hamiltonian constraint and finally determine it's quantum dynamics and whether it has GR as it's classical limit. Like I said, maybe I'll try to throw something together to explain this.