

How Symmetry Shapes Laws of Physics [video] - treefire86
https://www.quantamagazine.org/20150813-how-does-symmetry-shape-natures-laws/

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noobermin
We can thank Emmy Noether[0][1] for our current understanding of symmetries
and for how today we view such symmetries as being or underlying the
fundamental laws of physics.

[0] [http://arstechnica.com/science/2015/05/the-female-
mathematic...](http://arstechnica.com/science/2015/05/the-female-
mathematician-who-changed-the-course-of-physics-but-couldnt-get-a-job/1/)

[1] previous HN discussion:
[https://news.ycombinator.com/item?id=9606497](https://news.ycombinator.com/item?id=9606497)

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naringas
I'm extremely curious about the notions/concepts of symmetry in a more
mathematical sense, but from a philosophical perspective. I preliminarily
believe that symmetries may be related to the notion of novel information.

~~~
Retra
Sure, that's not unsurprising. Information symmetries are fundamental to how
you distinguish between states -- so much so that you could probably just
define information to be the manifestation of observational asymmetries.

~~~
williamjennings
Information already has a precise, functional definition in the context of
mathematics, machine learning, and AI. It is the number of bits necessary to
encode a message, and that is the most essential aspect of coding theory. I
would suggest reading the original works of Claude Shannon to become
enlightened about how the word 'information' is used in the context of math,
electrical engineering, and computer science.

The manifestation of observational asymmetries absolutely must be equivocal to
the asymmetry of manifest observation. Therefore, the format of an observation
is manifest via the symmetry of a relation under a set of attributes. Thusly,
the asymmetry of observations is a point measurably manifested by the
difference in attributes. That allows for the derivation of: a union operation
over the observations; an intersection operation over the asymmetries; and a
manifest closure property. This is how one may define points of 'data' in the
sense that is absolutely congruent with the terms database, big data, or data
science.

Information Theory and Relational Algebra have some overlap, but they are not
completely intertwined. The subjects of Abstract Algebra and Information
Geometry are there at the intersection, but they still too terminologically
distinct to be taught in tandem. The former subject is still best learned in
French; whereas the latter subject is still best learned in Japanese. It is
possible for one to teach themselves these subjects by machine translation, if
they have a deep understanding for the grammar and history of each language.
Deep learning of this sort is a kind of meditative activity, the type of which
is only available to the most erudite thinkers.

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renox
> Information already has a precise, functional definition in the context of
> mathematics, machine learning, and AI. It is the number of bits necessary to
> encode a message,

Precise?? You're joking right? Given that the number of bits necessary to
encode a message is highly depending on the way your message is interpreted..

If your bits are interpreted as either black or white, I need only 1 bit to
send a message indicating a color, if your bits are ASCII strings I need more
bits to send the same information..

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williamjennings
>Precise?? You're joking right? Given that the number of bits necessary to
encode a message is highly depending on the way your message is interpreted..

The interpretation is not the language. If a message consists of words, or is
mapped thereof; then there is an exact number of bits necessary.

>If your bits are interpreted as either black or white, I need only 1 bit to
send a message indicating a color, if your bits are ASCII strings I need more
bits to send the same information..

It seems like you are not familiar with the definition of bits. It is the
binary measure implicit to boolean algebra. Bits are not specifically ASCII
strings, because the former is a subset of the latter's characters.

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TTPrograms
Symmetry can also be very useful in the context of programming. In particular
I find loop invariants to be a very useful tool when building convoluted
looping algorithms - I'd guess you could formulate a similar symmetry for
recursive algorithms.

