Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Chris M. Thomasson" Newsgroups: sci.math Subject: Re: How many different unit fractions are lessorequal than all unit fractions? Date: Mon, 16 Sep 2024 15:03:45 -0700 Organization: A noiseless patient Spider Lines: 37 Message-ID: References: <405557f7289631d63264c712d137244c940b9926@i2pn2.org> <13c08e96ad635f8142b38d89863a80caf17a32a8@i2pn2.org> <4faa63d0ff8c163f01a38736aeb5732184218a29@i2pn2.org> <87jzfchnxc.fsf@bsb.me.uk> <87v7yvfeaf.fsf@bsb.me.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Tue, 17 Sep 2024 00:03:46 +0200 (CEST) Injection-Info: dont-email.me; posting-host="2d41bb0e6a21724e79465d793e720c2a"; logging-data="3219160"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+JgSCvrLq+Yt28Jd22J74gVBuH+d4swag=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:FvQuJogTiLIKmDZ/AZv2NYBMID4= Content-Language: en-US In-Reply-To: <87v7yvfeaf.fsf@bsb.me.uk> Bytes: 3559 On 9/16/2024 3:02 PM, Ben Bacarisse wrote: > "Chris M. Thomasson" writes: > >> On 9/15/2024 9:38 AM, Ben Bacarisse wrote: >>> "Chris M. Thomasson" writes: >>> >>>> On 9/14/2024 11:35 AM, joes wrote: >>>>> Am Sat, 14 Sep 2024 16:01:02 +0200 schrieb WM: >>>>>> On 14.09.2024 01:05, FromTheRafters wrote: >>>>>>> WM explained : >>>>>> >>>>>>>> No, that is your big mistake. In the interval [0, 1] there is a point >>>>>>>> next to 0 and a point next to 1, and infinitely many are beteen them. >>>>>>> Define 'next' in this context. >>>>>> Two points are next to each other means that no point is between them. >>>>> Which is the case for no two (different) reals. >>>> >>>> Two points on the real line that are different from one another have >>>> infinite points between them, and so on and so forth. :^) >>> It might be worth pointing out that any non-trivial interval [a, b] on >>> the real line (i.e. with b > a) contains an uncountable number of >>> points. Constructing the mid point and the quarter points and so on >>> only shows a countably infinite number of internal points, but giving a >>> bijection between [a, b] and [0, 1] shows that they have the same >>> cardinality. >> >> Agreed. Afaict, one way to cover all the points is to draw a solid line >> between two different points p0 and p1 where p0 does not equal p1. We can >> say the line covers them all? Fair enough? Put two different points on a >> piece of paper and draw a line from p0 to p1. That line contains infinitely >> dense points. > > Too much physics for me to comment. > Does it involve zooming into the drawn line with a very powerful microscope? ;^)