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Eckard Blumschein: on 11/5/09 at 23:23pm UTC, wrote Dear Navin, In order to reach a wider audience, couldn't you try and take...

Narendra Nath: on 10/30/09 at 17:29pm UTC, wrote Dear navin, i attempted the hard job of going through your essay when i...

Lawrence B. Crowell: on 10/2/09 at 22:16pm UTC, wrote I have only given this a skim reading so far, but this looks like a pretty...

Navin Sivanandam: on 10/2/09 at 10:54am UTC, wrote Essay Abstract The anthropic principle is an inevitable constraint...


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January 26, 2022

CATEGORY: What's Ultimately Possible in Physics? Essay Contest (2009) [back]
TOPIC: A Computational Anthropic Principle: Where is the Hardest Problem in the Multiverse? by Navin Sivanandam [refresh]
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Author Navin Sivanandam wrote on Oct. 2, 2009 @ 10:54 GMT
Essay Abstract

The anthropic principle is an inevitable constraint on the space of possible theories. As such it is central to determining the limits of physics. In particular, we contend that what is ultimately possible in physics is determined by restrictions on the computational capacity of the universe, and that observers are more likely to be found where more complicated calculations are possible. Our discussion covers the inevitability of theoretical bias and how anthropics and computation can be an aid to imposing these biases on the theory landscape in a systematic way. Further, we argue for (as far as possible) top-down rather than bottom-up anthropic measures, contending that that the latter can often be misleading. We begin the construction of an explicit computational measure by examining the effect of the cosmological constant on computational bounds in a given universe, drawing from previous work on using entropy production as a proxy for observers by Bousso, Harnik, Kribs and Perez. In addition, we highlight a few of the additional computational considerations that may be used to extend such a measure.

Author Bio

Navin Sivanandam received his PhD from Stanford University in 2008. He now works as a postdoc in the Theory Group at the the University of Texas at Austin, with his research focusing on string theory and cosmology. He also believes that foundational questions in physics are best discussed during the twilight hours over a fine single malt.

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Lawrence B. Crowell wrote on Oct. 2, 2009 @ 22:16 GMT
I have only given this a skim reading so far, but this looks like a pretty good essay. This has implications it seem for the information theoretic nature of the cosmological constant. Abhijnan Rej wrote a good paper on the computatibility of the cosmological constant:

I propose the cosmological constant is due to the occurrence of a quantum critical point or quantum phase transition in

I will give this a closer read over the next few days.

Cheers LC

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Narendra Nath wrote on Oct. 30, 2009 @ 17:29 GMT
Dear navin,

i attempted the hard job of going through your essay when i knew i hardly even comprehend your abstract. What i find now is that your approach is a kind of basic computational approach. It assumes in a way that the universe got created and evolved basically in a probalistic manner. Entropy then governs its evlotion completely.

However, the nature shows many symmetries too and then there are breakdown of some symmetries in isolated processes. May be yours is a kind of review of the topic chosen with not much of your own study and conclusions.Whatever little i have understood about Cosmology, to me it seems that it bears out the entire Physics from Particle Physics to Condensed matter physics. Nature being natural has to be simple, as per my imagination. What makes it complex is entirely due to we physicists. That is why i really enjoyed the last sentence of your essay, as it hit me to the inner core. What we humans are doing is just what our minds lead us to after all our sensors have given their respective signals for analysis and scrutiny and whatever background knowledge we have gained through our 'education'and the professional exposure/experience.

Are vwe free enough and unbiased to innovate Physics, rather than just extend it further with our base knowledge? The Big names in olden days Physics were all true innovators but today we mostly seem to extend their works through corrolleries. It may be my wrong impression but that is what is getting reflected in Nobel awards for life-time works or its implications reaching a huge economic or material gains! Physics in the early days was a purer persuit for academic curiousity and fulfilment of self persuits for common uplift of the standards of knowledge. But then xhange is the rule of nature and may be the new times will bring greater satisfaction to the human beings at large.

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Eckard Blumschein wrote on Nov. 5, 2009 @ 23:23 GMT
Dear Navin,

In order to reach a wider audience, couldn't you try and take issue concerning unseen deficits of theories as did I? Maybe you are able to refute 527.



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