Discussion of the proof that the uniform norm really is a norm

In response to a request on Piazza, I gave a detailed proof that the uniform really is a norm, including some comments and warnings on possible pitfalls along the way. Here (essentially) is what I said.

This post is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/10/discussion-of-proof-that-uniform-norm.html
Alternatively, a PDF of that post is available for viewing or downloading below.

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Converses and negations

One of our first-year students asked (on Piazza) whether converse and negation were the same thing. One of my colleagues explained the differences in terms of propositional logic. I added some comments afterward to see if some specific examples might help. I don’t know whether this helped or not! See below for what I said.

This post is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/10/converses-and-negations.html
Alternatively, a PDF of that post is available for viewing or downloading below.

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Revisiting liminf and limsup

My recent series of posts about Fatou’s Lemma for sums was aimed primarily at mathematics students at 3rd-year undergraduate level or above. So I think I should write a post more suitable for first-year undergraduate students. So I’m going to have another look at the topic of \liminf and \limsup for bounded sequences of real numbers (though most of what I say can be generalised to sequences, or even nets, of extended real numbers).

This post is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/revisiting-liminf-and-limsup.html
Alternatively, a PDF of that post is available for viewing or downloading below.

See also my earlier post
An application of absorption to teaching lim inf and lim sup (sequences)

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Sums and integration against counting measure: Appendix 5: Fatou’s Lemma for sums without using Measure and Integration

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (Appendix 5 to this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_30.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Appendix 4: More details about liminf

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (Appendix 4 to this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_81.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Appendix 3: Defining sums over sets without using Measure and Integration

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (Appendix 3 to this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_29.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Appendix 2: Proof of a claim about integrals from Part I

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (Appendix 2 to this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_79.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Appendix 1: Proof that counting measure really is a measure

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (Appendix 1 to this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_28.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Part IV

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (part IV in this series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_27.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Part IIIb

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (IIIb in the series) is available from my Blogger blog at https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_26.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Part IIIa

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This post (IIIa in the series) is available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_25.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Part II

For other posts in this series, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure

This second post in the series is now available from my Blogger blog at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting_24.html

Alternatively, a PDF of that post is available for viewing or downloading below.

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Sums and integration against counting measure: Part I

[Note: I really prefer the way the maths looks using MathJax, which I use on Blogger (at no cost). Unfortunately I am unable to use MathJax on this WordPress Blog. In future I will write my mathematical posts on Blogger, and link to them from a short post here, perhaps with an image of the introduction. The MathJax version of this post is available at
https://explaining-maths.blogspot.com/2023/08/sums-and-integration-against-counting.html
For all of my Blogger posts on this topic, see
https://explaining-maths.blogspot.com/search?q=Sums+and+integration+against+counting+measure]

Note added 30/8/23: I’m not quite sure when I started to say “integration against a measure”. I’m not alone, but I think that “integration with respect to a measure” is a lot more common! However, I don’t want to change the titles of my latest 10 blog posts, so I’ll leave it as it is. I’ll probably change back to “integration with respect to a measure” in future though!

A PDF version of the Blogger version of the post, for viewing or download. Below that is the version typed on WordPress, where I think that the maths doesn’t look as clear.

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Taster Sessions Update 16, July 1st 2022

For more posts about our maths taster sessions (https://tinyurl.com/uonmathstaster), see https://tinyurl.com/uonmathstasterposts

You may be interested in a free, in-person event with some maths taster sessions at the University of Nottingham under the auspices of the Advanced Mathematics Support Programme:

Moving on with Maths
July 7th 2022, 1-4:30PM
University of Nottingham

See https://tinyurl.com/UoNMowM for full details and how to book a place. Or you can use this QR code:

Moving on with Maths
July 7th 2022

If you have missed some of our previous maths taster sessions, you can watch recordings of most of these, as well as some of our other maths talks. See https://tinyurl.com/uonmathstasterposts

If you know of anyone else who might be interested in this information, it would be great if you could pass this information on!

Best wishes,
Joel Feinstein

Study with us: https://tinyurl.com/mathscourseuon
Our quarterly maths e-Newsletter: https://tinyurl.com/uonmathsnews
Maths Taster Sessions: https://tinyurl.com/uonmathstaster