Tuesday, July 26, 2005

Lee Smolin's Case for Background Independence

While we were privy to the debate between Susskind and Smolin in a previous post, the origins and definitions have been drawn from the deeper requirements of an ideology.

Where do these begin, and we find the inner compulsion of a scientist to find the means and defintions to extend the basis of our perceptions on a basis that both agree.

Lubos reaffirms this many times, and is in concert, as many in string theory continue to hold to what this desire should be.

Lubos saids:
Some of Lee's points can be agreed with, for example:

It is desirable to find a background independent formulation of string/M-theory

Such a formulation would likely to answer the questions whether the landscape approach to string/M-theory is correct; why it's not; what it should be replaced with.

This post represents a becoming. From those deeper levels, such a stage must be set?

Good for Lee Smolin, and the work he has been doing for laying a foundation, that all see, must reside to an synoptic closure, before such progressions become. If it got Lee smolin and others thinking, then, it served it's purpose, and those who say, a waste of time, would have undertsood then, Lee Smolin would not be where he is today on the pdf file here written.

So has Lubos has then directed our perspective in relation to how Lee Smolin sees the issues, and we have found the direct relationship and difference between how M Theory apporaches and How LQG does.

Lubos Motl saids:
An attempt to revive Mach's principle means to argue that the gravitational waves do not exist. It is a struggle to return us not only before General Relativity; it is a program to return the humankind to the pre-Newtonian era and the dark Middle Ages. Some people may be permanently impressed by Mach's principle and some people may find it shallow after a closer scrutiny. These two groups may be composed of equally nice people. But the difference is that the critics of Mach's principle have a good physical intuition; its advocates are philosophers who are unable to think analytically and quantitatively and they prefer to insist on prejudices that can be shown flawed by a five-minute-long quantitative argument.

There are catelysts all around, that ask for this deeper resolve to come forth. Asking for greater potentials in our visionistic qualities, to understand, that we can see this world very much differently? What pathway had been established then that Lee Smoln would attack this from another perspective held within the ideas of Special Relativity, that holds the idealization before the roads to gravitational understanding had been theoretically proven by Einstein.

Lubos Said:>
OK, let me start with the questions about relationism and Mach's principle. I highly recommend you the second popular book by Brian Greene, "The Fabric of the Cosmos", where the relative vs. absolute debate is covered in the first chapters. And the presentation is very nice.

How often the debate on such levels of what seems has been lacking in string/M theory that such voices extolled would relinquish it to paths unexperimentally challenged? They would have missed the opportunity ofsuch a debate brought forth from the Dialogos of Eide.

It is a strong statement which arises from the Platonic school, that such a discussion would reveal, that what is in the Heaven of ideas, could descend to minds and those who ask, those who embroil themselves, to questions of what it is, that makes the ideas of reality, a part of the natural world.

Lee Smolin:
The aim of this paper is to explain carefully the arguments behind the assertion that the correct quantum theory of gravity must be background independent. We begin by recounting how the debate over whether quantum gravity must be background independent is a continuation of a long-standing argument in the history of physics and philosophy over whether space and time are relational or absolute. This leads to a careful statement of what physicists mean when we speak of background independence. Given this we can characterize the precise sense in which general relativity is a background independent theory. The leading background independent approaches to quantum gravity are then discussed, including causal set models, loop quantum gravity and dynamical triangulations and their main achievements are summarized along with the problems that remain open. Some first attempts to cast string/M theory into a background independent formulation are also mentioned.

The relational/absolute debate has implications also for other issues such as unification and how the parameters of the standard models of physics and cosmology are to be explained. The recent issues concerning the string theory landscape are reviewed and it is argued that they can only be resolved within the context of a background independent formulation. Finally, we review some recent proposals to make quantum theory more relational.

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