Talk:String theory landscape

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The Anthropic Principle may be a fallacious concept, since "evolutionary life" can evolve in many environments with sufficient complexity to allow (a) formation (b) imperfect reproduction (c) limits on smoothly declining resources required for such reproduction (evolution cannot take place if the pace of change is past the "organism"'s limits). In other words, there can be many forms of life that could evolve in many different universes with different physical laws. So long as those universes provide a base for any feasible form of life. For example we can replay the evolution of various conceptual forms of life inside computer systems, using multiple varying environments. Of course, for all that above, we depend an agreed concept to fit the word "life". So any partitioning of physics predicated on the Anthropic Principle and an ill-agreed definition of the concept of life might appear to be weakly based? jjalexand

"the idea that fundamental constants may have the values they have not for fundamental physical reasons, but rather because such values are necessary for life (and hence intelligent observers to measure the constants)" may be read by a non expert as teleology and thus he may conclude that physicists are not very serious people. It may also be read as a confirmation of "intelligent design". Manuel

The term "anthropic landscape" is a little misleading, IMO, because it's actually the antithesis of anthropic arguments. The strong and weak versions of the anthropic principle take it for granted that ours is the only universe (the strong one certainly does; the weak one is perhaps a little more agnostic on the subject.) The so-called "anthropic landscape" is simply a hypothesis (and is also a metaphysical claim, I might add) that tries to explain the existence of a fine-tuned universe in which humans live (or, more broadly, in which there is intelligent life--taking for granted that our universe, or any universe with intelligent life, is indeed fine-tuned to some unusual degree) by dismissing the question. It states that our universe might be unusual, but it is not arbitrary--that is, the good reason for its existence is just that there are so many actual universes that one like ours was bound to be in the mix. It's "anthropic" in that it attempts to deal with the reasons for the existence of our universe, but that's as far as it goes. It actually attempts to rebut anthropic arguments, which is why I find it very confusing to call it an "anthropic" landscape.

IMO, and as I understand it, anyway.

(Also, Stephen Weinberg has stated that he doesn't think there's anything to explain. Our universe is neither fine-tuned nor unusual, he says. I am not aware that he has changed his mind. Here are a couple of relevant links:

http://www.meta-library.net/transcript/wein-body.html

http://www.nyu.edu/classes/neimark/design.html) Mzed 21:43, 21 April 2006 (UTC)Reply

How sad that physicists are wasting their lives on such nonsense as string theory. Can anyone believe with a straight face that such things as strings and branes really exist? —Preceding unsigned comment added by 69.228.215.104 (talk) 02:42, 2 December 2007 (UTC)Reply

Actually, string mathematic lands have strong chances for exsisting, and I would totally revile otherwise estimates on the subject —Preceding unsigned comment added by 92.232.91.38 (talk) 12:47, 21 September 2008 (UTC)Reply

On Probabilities

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From the article: "Interpreting probability in a context where it is only possible to draw one sample from a distribution is problematic".

No, it isn't. The interpretation of probabilities within the bayesian paradigm have nothing to do with having to make many independent samples. Bayesian probability is a proxy for degrees of "sureness" about logical statements. What you extract from many independent samples in this context are not probabilities, but frequencies. The thing is that bayesian probabilities converge for frequencies in the limit of many samples.

For details on this please see refs [1] [2] "Probability Theory As Extended Logic". Retrieved 17/01/2011. {{cite web}}: Check date values in: |accessdate= (help)


  1. ^ Jaynes, Edwin (2003). Probability Theory: the Logic of Science. Cambridge University Press. ISBN ISBN 0-521-59271-2. {{cite book}}: Check |isbn= value: invalid character (help)
  2. ^ Cox, R. T. (1961). The Algebra of Probable Inference. Johns Hopkins University Press.

Poor Background

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This article does a really lousy job of setting the stage for the reader in terms of background information. Almost the entire article is analysis and commentary on a large landscape, without giving the reader a sense of how the landscape came to be. In particular, I feel the article needs to spend more time describing the string theory vacuum, the alternative configurations that lead to such numerous vacua, and the motivation for finding a small cosmological constant on the landscape. It is far from obvious whether a "small" cosmological constant is even within the overall parameter space (in a technical sense--experts comments suggest so, but what data is leading them there?). 70.247.175.236 (talk) 07:49, 1 January 2014 (UTC)Reply

Clarifications

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I'm not sure it is the same thing, but other articles seems to currently suggest that the string theory vacuum is synonymous with the string theory landscape. If so, can someone please create a redirect form string theory vacuum? The reason I'm not sure is that the lead to this article seems to suggest that the landscape only applies to "false vacuums". That sounds rather dubious to me, but if it's true, it highlights the need for clarity in describing both string theory vacuum and string theory landscape. 70.247.167.104 (talk) 07:05, 6 January 2014 (UTC)Reply

Compactification

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This article mentions the landscape as possible compactifications of extra dimensions, but I don't find anything related to compactifications here:

https://theconversation.com/the-theory-of-parallel-universes-is-not-just-maths-it-is-science-that-can-be-tested-46497 — Preceding unsigned comment added by 70.247.166.192 (talk) 13:59, 6 September 2015 (UTC)Reply

inconsistent tagging nothing apparently going on here

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String theory is inaccessible to the many, it's not remotely a popular topic as far being able to say anything other than "wee strings" or "1-dimensional strings". In general, while at one time this sort of tagging was tolerated, it's generally gone on articles in advanced physics, mathematics, for the obvious reason, i.e. this isn't the simple English wiki. and the tags are topic inappropriate. If the content is muddled or fails to present the subject matter cogently to a person with the minimal required education, that's quite a different matter, 'The landscape" is an advanced topic, not "introduction to string theory". 98.4.124.117 (talk) 01:41, 6 August 2018 (UTC)Reply

The over the top tagging of every sentence is a similar deal, will come back for that after awaiting comment. I'm not a fan or partisan of the landscape theory but I am an opponent of dragging the site down like this. Create simple:String theory landscape if you think it's worth it, stop dragging the rest of us down. 98.4.124.117 (talk) 01:50, 6 August 2018 (UTC)Reply