SemiAccurate Forums  

 
Go Back   SemiAccurate Forums > Main Category > Off topic

Off topic Posts not related to technology


Reply
 
Thread Tools Display Modes
  #71  
Old 05-26-2011, 08:19 PM
rambaldi's Avatar
rambaldi rambaldi is offline
2^11
 
Join Date: Jan 2010
Location: Auckland, New Zealand
Posts: 2,435
rambaldi will become famous soon enoughrambaldi will become famous soon enough
Default

Quote:
Originally Posted by Brother Michigan View Post
Now HERE'S the big statement I have a problem with. If you go with the point of view that Susskind proposes, which is that the universe is NOT the same everywhere, you're advocating against the cosmological principle and suddenly every observation you make or experiment you do is completely useless since it only applies to the tiny region of space we currently occupy. If you believe this, then you believe that true science is impossible; you can't possibly construct any sort of universal model if the rules change from place to place. I've brought this point up to a few of Susskind's most devout followers that I know and they all tend to get a little fidgety and suddenly want to change the subject. I have yet to get a satisfactory answer as to how Susskind's point of view doesn't violate the cosmological principle or, if it does violate it but somehow doesn't matter, why it doesn't matter.
+1 for what I was thinking as I read that statement.
__________________
E-Peen: AMD Phenom II x4 965 (stock) | MSI 790FX-GD70 | ATI HD 5970 (stock) | Kingston HyperX DDR3 1333 CL7 2x2GB | Seagate 7200.12 4x1TB | Ikonic RaX10 Liquid
Reply With Quote
  #72  
Old 05-27-2011, 06:27 AM
system7's Avatar
system7 system7 is offline
2^11
 
Join Date: Apr 2010
Location: Portsmouth, UK
Posts: 2,650
system7 will become famous soon enough
Default

Quote:
Originally Posted by Brother Michigan View Post
Now HERE'S the big statement I have a problem with. If you go with the point of view that Susskind proposes, which is that the universe is NOT the same everywhere, you're advocating against the cosmological principle and suddenly every observation you make or experiment you do is completely useless since it only applies to the tiny region of space we currently occupy. If you believe this, then you believe that true science is impossible; you can't possibly construct any sort of universal model if the rules change from place to place. I've brought this point up to a few of Susskind's most devout followers that I know and they all tend to get a little fidgety and suddenly want to change the subject. I have yet to get a satisfactory answer as to how Susskind's point of view doesn't violate the cosmological principle or, if it does violate it but somehow doesn't matter, why it doesn't matter.
The "Cosmological Principle" was something I had never heard of! Where did you find it? That is philosophy, isn't it?

OK, you're saying the rules of physics have to be the same everywhere to be elegant. I call that the equivalence principle which Einstein took as bedrock. You want the mass of an electron to be the same in every place, and I think it IS in our corner of the megaverse of possibilities that string theory can deal with. What's the problem? I don't see one.

String theory is a GEOMETRIC interpretation of the universe at heart. Everything is simple strings and there's really only two types, closed and open. The cleverness is in the 10 dimensions and the geometry, and the effects of branes (Which are just geometrical mappings, IMO).

Let me tell you something strange about an electron. Firstly it is really just the same as a muon or a tauon, only the mass is different. Secondly, in information terms you can only measure ONE thing about it, which is spin up or spin down. Everything else is just flannel! The mass really doesn't matter, and you can change it!

Now this following bit of geometry is not just some abstract thing, but maybe the rules of the universe we live in, generating NUMBERS from shapes and strings. In this case, quantum theory conservation rules.


http://video.google.com/videoplay?do...4599825291409#
__________________
Best Regards from Steve in Portsmouth, UK.
Reply With Quote
  #73  
Old 05-27-2011, 01:59 PM
Brother Michigan's Avatar
Brother Michigan Brother Michigan is offline
640k who needs more?
 
Join Date: Feb 2010
Location: Lexington, KY
Posts: 862
Brother Michigan will become famous soon enough
Default

The Cosmological Principle definitely starts to get into the realm of scientific philosophy, and it makes a lot of sense. It's not so much a question of the elegance of a theory, but rather its applicability. String theory proposes itself as a theory of the universe, the "theory of everything", if you will. This is great and I think it's a definite possibility that it might be true, but you can't believe that and also advocate against the cosmological principle. The big problem is that string theory can't produce a model of the universe if the laws it's trying to describe don't apply everywhere. A theory must try to fit observation and experiment, but if the properties of the universe vary on smaller scales than the observations we are able to make, any theory trying to that "fits" those observations must be wrong. Then again, if the properties of the universe vary on scales larger than what we are able to observe, the statement itself is inherently false since those variations cannot be causally connected to us (i.e. what we call the universe must therefore be homogeneous in its behavior, as proposed by the cosmological principle).

The cosmological principle is such a simple statement on its surface, but it really is the basis of all sciences that concern themselves with the large-scale properties of the universe.

Now, if you just want to advocate string theory as a new interpretation of nuclear and high energy physics, that's just fine and Susskind's statement has no bearing on the discussion, but then I'd have to argue that we have descriptions now that are more simple and aren't yet irrevocably broken.
Reply With Quote
  #74  
Old 05-28-2011, 11:31 AM
system7's Avatar
system7 system7 is offline
2^11
 
Join Date: Apr 2010
Location: Portsmouth, UK
Posts: 2,650
system7 will become famous soon enough
Default

Mate, you're in the wrong thread. Philosophy is next door! Back to 10 dimensions...

Here's quite a nice short video about imagining 4 dimensions, using an unfolded 4D hypercube embedded in 3. Just to convince you the maths is easy enough.
http://www.youtube.com/user/mathemam.../9/KdvjfcMUovo

This brings me on to the Klein Bottle which is an entirely surprising object even embedded in our 3 dimensions. It's a Torus with a twist at heart, but has a property called being non-orientable, which means on the 2D surface, left and right have no meaning. In 3D it has an issue, in that surfaces intersect (A D1 Brane?), but in 4D space it's not a problem. I'm trying to figure out what use that is in string theory. Maybe electromagnetic charge, maybe a boson. Not sure.

Uploaded with ImageShack.us

Nice short video here:
http://www.youtube.com/watch?v=sRTKSzAOBr4
__________________
Best Regards from Steve in Portsmouth, UK.
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Forum Jump


All times are GMT -5. The time now is 07:13 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
SemiAccurate is a division of Stone Arch Networking Services, Inc. Copyright 2009 Stone Arch Networking Services, Inc, all rights reserved.