Infinite dimensional Hilbert Space

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Discussion Overview

The discussion revolves around the interpretation of a photo of David Hilbert in relation to the concept of infinite-dimensional Hilbert spaces. Participants explore the implications of the term "infinite-dimensional" and its connection to the context of the image and the accompanying notes.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions the literal interpretation of the photo's caption, suggesting it may be a joke rather than a serious reference to Hilbert spaces.
  • Another participant clarifies that Hilbert spaces can be finite or infinite-dimensional, noting that infinite-dimensional Hilbert spaces consist of infinite sequences treated as vectors.
  • There is a suggestion that the context of the photo and additional images would help clarify the discussion.
  • One participant asserts that the notes linked do not pertain to Hilbert spaces, implying that the photo may not be relevant to the topic.
  • Another participant raises a question about the relationship between infinite-dimensional spaces and manifolds, indicating a need for clarification on this point.
  • There is mention of Banach manifolds, with a participant expressing limited knowledge on the topic.

Areas of Agreement / Disagreement

Participants express differing views on the relevance of the photo to the concept of infinite-dimensional Hilbert spaces, with no consensus reached on its interpretation or the implications of the discussion regarding manifolds.

Contextual Notes

Some participants note the absence of a metric in the discussion of Hilbert spaces, which may affect the interpretation of the concepts being discussed. Additionally, the relationship between infinite-dimensional spaces and manifolds remains unresolved.

kent davidge
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Could someone tell me in what sense the following photo of Hilbert is a infinite dimensional Hilbert Space?
xNNpZry.png


It's shown in a pdf I'm reading.

Perhaps I'm putting the chariot in front of the horses as one would say here in our country, by considering infinite as infinite dimensional?
 

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Are you sure this is meant literally? It may be a joke comment. A Hilbert space is a metric space. I don't see any mention , neither implicit nor explicit of any metric.
 
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A Hilbert space can be finite-dimensional or infinite-dimensional. The objects in an infinite-dimensional Hilbert space are infinite sequences, and are considered to be infinite-dimensional vectors.

The caption under the picture isn't a Hilbert space, obviously -- I believe it is merely commenting on what is probably his most well-known work.
 
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May be if you show pictures (a), (b), ..., (o) and the context of all this would be better.
 
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Here is the pdf https://web.stanford.edu/~jchw/WOMPtalk-Manifolds.pdf
 
Well, you can safely ignore that bit, these notes are not about Hilbert spaces. The picture is of course Hilbert himself, not a Hilbert space, perhaps it is supposed to be witty. If the space is infinite dimensional then it is not a manifold. I think that is the point to realize.
 
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martinbn said:
If the space is infinite dimensional then it is not a manifold.
Why that?
 
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Yes, but the notes from the link consider only manifolds that a locally ##\mathbb R^n##.
 
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Yes, there are Banach manifolds too, but it font know enough about them.
 
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